Spec Power Plant TGG Ciclo Aberto Iraque

Document No. 62010/IPA/000001 Rev A FRONTPAGE.DOC/S1/1/PMO

IRAQ POWER RECONSTRUCTION

GAS TURBINE POWER STATION VOLUME 1 TECHNICAL SPECIFICATION VOLUME 2 TECHNICAL SCHEDULES VOLUME 3 ENQUIRY DRAWINGS VOLUME 4 APPENDICES AUGUST 2004

IRAQ POWER RECONSTRUCTION GAS TURBINE POWER STATION VOLUME 1 TECHNICAL SPECIFICATION AUGUST 2004

IRAQ POWER RECONSTRUCTION GAS TURBINE POWER STATION VOLUME 1 TECHNICAL SPECIFICATION AUGUST 2004

Document No. 62010/IPA/000001 Rev A 0654S000.DOC/S1/2/PMO

- 1 -

LIST OF REVISIONS

Current Rev.

Date Page affected

Prepared by

Checked by (technical)

Checked by (quality

assurance)

Approved by

A

Aug 2004

All

J GOLDSMITH C JACKSON

J SAMS S WATT

J LIDDLE

MA MITCHELL

J LIDDLE

Original

Aug 2004

All

REVISION DETAILS

Original issue as Document No. 62010/IPA/000001

A

Aug 2004

All

Final issue as Document No. 62010/IPA/000001


(i)

CONTENTS

Page

LIST OF ABBREVIATIONS

1. PROJECT DESCRIPTION 1.1

1.1 General 1.1 1.2 Site Description 1.1 1.3 Target project start and completion 1.1

2. PLANT DESIGN CRITERIA 2.1

2.1 General 2.1 2.2 Unit rating 2.1 2.3 Site layout 2.2 2.4 Plant operating philosophy 2.2

2.4.1 Site conditions 2.2 2.4.2 Fuel/water supplies 2.3 2.4.3 Grid conditions 2.3

2.5 Seismic design 2.3 2.6 Performance criteria 2.3

2.6.1 Output and heat rate 2.3 2.6.2 Plant start up 2.4

2.7 Environmental criteria 2.4

2.7.1 Noise 2.4 2.7.2 Emissions to air 2.6 2.7.3 Ambient air quality 2.7 2.7.4 Aqueous emissions 2.7 2.7.5 Visual impact 2.8

3. SCOPE OF WORK 3.1

3.1 Summary of main scope and services 3.1 3.2 Terminal points 3.6

3.2.1 Fuel supplies 3.7 3.2.2 Water supplies 3.7 3.2.3 Electrical connections 3.7 3.2.4 Communications 3.7 3.2.5 Drainage 3.7 3.2.6 Security fencing and access roads 3.8

4. GENERAL REQUIREMENTS 4.1

4.1 Programmes and progress 4.1

4.1.1 Programme requirements 4.1 4.1.2 Progress reporting 4.3

4.2 Design and standardization 4.5 4.3 Drawings and documents 4.8


(ii)

Page

4.3.1 Drawings enclosed with the Specification 4.8 4.3.2 Schedules 4.8 4.3.3 Drawings and documents to be submitted by the

Tenderer 4.9 4.3.4 Drawings and documents to be submitted by the

Contractor 4.9 4.3.5 Drawings and document format 4.10 4.3.6 Drawing sheet numbers 4.11 4.3.7 Drawing and document revision 4.11 4.3.8 Drawing and document status 4.12

4.4 Operating and maintenance instructions 4.12 4.5 HAZOP studies 4.17 4.6 Places of manufacture, testing and inspection 4.17 4.7 Packing and marking on packages 4.17 4.8 Training 4.17

4.8.1 General 4.18 4.8.2 Content of training 4.18

4.9 Spare parts 4.19 4.10 Special tools and lifting devices 4.20 4.11 Warranty engineer 4.20

5. SITE DETAILS AND SAFETY REQUIREMENTS 5.1

5.1 Location of Site, access and use of Site 5.1 5.2 Site facilities 5.2 5.3 Site services during construction period 5.3

5.3.1 Site construction electricity supplies 5.3 5.3.2 Water supplies 5.3 5.3.3 Other services 5.4

5.4 Health and safety at work 5.4

5.4.1 Risk assessment 5.5 5.4.2 Specific risks produced by contractor activities 5.5 5.4.3 Documents 5.6 5.4.4 Contractor's safe systems of working 5.6 5.4.5 Training 5.7 5.4.6 Safety equipment 5.7 5.4.7 Assistance to Owner 5.8 5.4.8 Confined spaces 5.8 5.4.9 Land owned by third parties 5.9 5.4.10 Temporary electricity supply 5.9 5.4.11 Fire precautions 5.9 5.4.12 Compressed gases 5.9 5.4.13 Access, fencing and safety barriers 5.9 5.4.14 Site rules 5.9 5.4.15 First aid and medical facilities 5.11 5.4.16 Emergency evacuation of the Site 5.11 5.4.17 Safety management 5.11 5.4.18 Cranes, hoists, lifting equipment and scaffolds, etc 5.11 5.4.19 Electrical safety conditions 5.11

6. MECHANICAL PLANT AND SYSTEMS 6.1


(iii)

Page

6.1 Gas turbines 6.1

6.1.1 General 6.1 6.1.2 Turbine 6.2 6.1.3 Compressor 6.2 6.1.4 Casings 6.2 6.1.5 Turbine and compressor rotors 6.3 6.1.6 Blading 6.3 6.1.7 Burners and combustion system 6.3 6.1.8 Couplings 6.4 6.1.9 Compressor cleaning 6.4 6.1.10 Starting equipment 6.5 6.1.11 Rotor barring 6.5 6.1.12 Auxiliary gear 6.5 6.1.13 Gas turbine generator lubrication system 6.6 6.1.14 Combustion air inlet system 6.9 6.1.15 Gas turbine exhaust 6.11 6.1.16 Gas turbine enclosure 6.13

6.2 Fuel systems 6.16

6.2.1 Fuel gas supply system 6.16 6.2.2 Fuel oil supply system 6.24

6.3 Water supply and waste water systems 6.29

6.3.1 General 6.29 6.3.2 Scope of work 6.30 6.3.3 Raw water supply 6.30 6.3.4 Service water 6.30 6.3.5 Demineralized water 6.32 6.3.6 Potable water system 6.33 6.3.7 Chemicals 6.35 6.3.8 Laboratory 6.36 6.3.9 Waste water systems 6.37

6.4 Closed circuit cooling water system 6.38

6.4.1 General 6.38 6.4.2 Scope of Work 6.39 6.4.3 System design and operation 6.39 6.4.4 Air blast cooler 6.40 6.4.5 Header tank 6.42 6.4.6 Cooler controls 6.42

6.5 Fire protection and detection 6.42

6.5.1 General requirements 6.42 6.5.2 Scope of Supply 6.43 6.5.3 Fire water supply 6.43 6.5.4 Fire fighting systems 6.45

6.6 Instrument and service air systems 6.52

6.6.1 General 6.52 6.6.2 Scope of work 6.53

6.7 Painting and protection against corrosion 6.57


(iv)

Page

6.7.1 Painting 6.57 6.7.2 Galvanising 6.57

6.8 Cathodic protection 6.58 6.9 Cranes and lifting equipment 6.58

6.9.1 General 6.58 6.9.2 Electrical overhead travelling cranes 6.58 6.9.3 Mobile cranes 6.58 6.9.4 Runway beams and lifting facilities 6.59 6.9.5 Testing 6.59 6.9.6 Use of cranes for initial erection 6.59

6.10 Workshop, stores and equipment 6.59

6.10.1 General 6.59 6.10.2 Workshop compressed air system 6.60 6.10.3 Stores equipment 6.60

6.11 General plant requirements 6.60

6.11.1 Plant referencing 6.60 6.11.2 Nameplates and labels 6.61 6.11.3 Plant vibration 6.62 6.11.4 Sunshades 6.62 6.11.5 Special tools and tackle for maintenance 6.63 6.11.6 Locks and keys for mechanical plant 6.63 6.11.7 General mechanical requirements 6.63 6.11.8 Erection of pipework 6.66 6.11.9 Pipe supports and expansion 6.66 6.11.10 Low pressure pipework 6.66 6.11.11 Steelwork 6.83 6.11.12 Safety guards for plant and apparatus 6.85

6.12 Packing and marking on packages 6.85

6.12.1 Receipt and storage at site 6.85 6.12.2 Erection mark 6.86

7. ELECTRICAL 7.1

7.1 Generators 7.1 7.2 Excitation system and equipment 7.2 7.3 Generator main connections, neutral earthing and switchgear 7.3

7.3.1 General 7.3 7.3.2 Generator switchgear 7.3

7.4 Transformers 7.4

7.4.1 General 7.4 7.4.2 Dry type transformers 7.4 7.4.3 Oil filled transformers 7.4

7.5 Switchgear 7.6

7.5.1 General 7.6


(v)

Page

7.5.2 MV switchgear 7.6 7.5.3 LV and dc switchgear 7.7

7.6 Current transformers 7.8 7.7 Voltage transformers 7.8 7.8 DC supplies system 7.8 7.9 Uninterruptible power supply equipment 7.9 7.10 Protection 7.9

7.10.1 General 7.9 7.10.2 Generator protection 7.10 7.10.3 Generator transformer protection 7.10 7.10.4 Unit transformer protection 7.11 7.10.5 Dry type transformer protection 7.11 7.10.6 Black start/emergency diesel generator protection 7.11

7.11 Synchronizing 7.12 7.12 Black start/emergency diesel generator 7.12 7.13 Metering 7.13 7.14 Motors 7.13 7.15 Earthing 7.13 7.16 Cabling 7.14

7.16.1 General 7.14 7.16.2 Medium voltage cables 7.15 7.16.3 Low voltage cables 7.15 7.16.4 Control and instrumentation cables 7.15 7.16.5 Optical fibre cables 7.15 7.16.6 Telephone cables 7.15 7.16.7 High temperature cables 7.16 7.16.8 Intrinsically safe cables 7.16 7.16.9 Mineral insulated cables 7.16 7.16.10 Cable installation 7.16

7.17 Static frequency converter 7.18 7.18 Electrical equipment for hazardous areas 7.18

8. CONTROL, INSTRUMENTATION AND COMMUNICATIONS 8.1

8.1 Introduction 8.1 8.2 Scope of supply 8.1 8.3 Objectives 8.2 8.4 Operational philosophy 8.3 8.5 Control and monitoring of plant 8.4

8.5.1 Gas turbine 8.4 8.5.2 Auxiliary plant 8.5 8.5.3 Generator 8.5 8.5.4 Electrical distribution system 8.6

8.6 Plant control system 8.7

8.6.1 General system design 8.7 8.6.2 Operator’s facilities 8.8 8.6.3 Engineer’s workstation 8.8 8.6.4 System response times 8.9 8.6.5 Spare capacity 8.9 8.6.6 Software 8.9


(vi)

Page

8.7 Metering 8.12 8.8 Uninterruptible power supply 8.12 8.9 Condition monitoring 8.13 8.10 Plant performance monitoring 8.13 8.11 Emissions monitoring 8.14 8.12 Station clock system 8.14 8.13 Load dispatch 8.15 8.14 Fire detection and alarm system 8.15 8.15 Gas detection system 8.16 8.16 Private automatic branch exchange (PABX) 8.16 8.17 Public address system 8.17 8.18 Closed circuit television, intruder detection and site access control

systems 8.17 8.19 Weather station 8.18 8.20 General requirements 8.19

8.20.1 Introduction 8.19 8.20.2 Environmental requirements 8.19 8.20.3 Hazardous areas 8.19 8.20.4 Insulation and isolation 8.19 8.20.5 Electromagnetic compatibility (EMC) 8.20 8.20.6 Identification 8.20 8.20.7 Installation 8.20 8.20.8 Flow measurements 8.21 8.20.9 Level measurements 8.21 8.20.10 Pressure measurements 8.22 8.20.11 Temperature measurements 8.22 8.20.12 Position measurements 8.23 8.20.13 Quality measurements 8.23 8.20.14 Vibration measurements 8.23 8.20.15 Control valves and actuators 8.23 8.20.16 Motorized valves 8.24 8.20.17 Manual valves 8.24 8.20.18 Pneumatic actuators/positioners 8.24 8.20.19 Cubicles and racks 8.25

9. CIVIL WORKS 9.1

9.1 General requirements for civil works 9.1

9.1.1 General 9.1 9.1.2 Civil programme and method statements 9.1 9.1.3 Planning and building permits/approvals 9.1 9.1.4 Site investigations 9.2 9.1.5 Ground contamination 9.2 9.1.6 Design and construction 9.2

9.2 The site specific data 9.3

9.2.1 General 9.3

9.3 Scope of civil engineering and building works 9.3

9.3.1 General 9.3 9.3.2 The Contractors enabling works 9.3 9.3.3 Scope of main civil engineering and building works 9.4


(vii)

Page

9.4 Design of the works 9.16

9.4.1 General 9.16 9.4.2 Preferred structural design concept 9.18 9.4.3 Materials 9.23 9.4.4 Civil design parameters 9.23

9.5 Specific building and architectural requirements 9.34

9.5.1 Cladding and decking 9.34 9.5.2 Metal doors and frames 9.39 9.5.3 Internal doors and frames 9.40 9.5.4 Internal vision panels 9.41 9.5.5 External walling 9.41 9.5.6 Internal masonry walling 9.42 9.5.7 Suspended ceilings 9.42 9.5.8 Damp proofing 9.43 9.5.9 Stairs 9.43 9.5.10 Sanitary ware 9.43 9.5.11 Finishes 9.43 9.5.12 Flat roof waterproofing systems (if required) 9.45

9.6 Materials and workmanship 9.46

9.6.1 Codes and Standards 9.46 9.6.2 Materials 9.46 9.6.3 Certification of materials 9.46 9.6.4 Storage of materials 9.47 9.6.5 Plant and equipment 9.47 9.6.6 Concrete 9.47 9.6.7 Setting out and monitoring 9.51 9.6.8 Earthworks, excavation and filling 9.52 9.6.9 Roads, hardstandings, car parks and paths 9.52 9.6.10 Piling 9.52 9.6.11 Structural steelwork 9.53 9.6.12 Surface water drainage and buried pressure pipelines 9.57 9.6.13 Building drainage 9.57 9.6.14 Brickwork and blockwork 9.57 9.6.15 Builder’s work 9.58 9.6.16 Access 9.58 9.6.17 Fencing 9.58 9.6.18 Landscaping 9.60 9.6.19 Laydown area 9.61

9.7 Electrical building services 9.61

9.7.1 Scope of works 9.61 9.7.2 Lighting systems 9.61 9.7.3 Small power installation 9.70 9.7.4 Distribution system 9.72 9.7.5 Cables and wiring 9.73 9.7.6 Lightning protection system 9.74

9.8 Mechanical Building Services 9.75

9.8.1 Scope of Works 9.75 9.8.2 Design information 9.76 9.8.3 Quality control 9.77 9.8.4 Domestic hot and cold water services 9.77


(viii)

Page

9.8.5 HVAC systems 9.78

9.9 Subcontractors 9.85 9.10 Functional requirements 9.85 9.11 Record drawings 9.86

10. QUALITY CONTROL, INSPECTION AND TESTING 10.1

10.1 General 10.1 10.2 Extent of work 10.2 10.3 Document submission 10.2 10.4 Inspection notification and right of access 10.4 10.5 Inspection and tests 10.4 10.6 Non-conformances 10.5 10.7 Quality control records, certificates and certificates of conformance 10.6 10.8 Specific tests and inspections 10.7

11. COMMISSIONING, START-UP AND TESTS ON COMPLETION 11.1

11.1 General 11.1 11.2 Commissioning 11.1

11.2.1 Commissioning procedures 11.1 11.2.2 Precommissioning 11.2 11.2.3 Commissioning 11.3 11.2.4 Tests on completion 11.3 11.2.5 Start up guarantee tests 11.4

11.3 Guarantee and performance tests 11.4

11.3.1 Output and heat rate performance guarantee tests 11.4 11.3.2 Environmental performance guarantee tests 11.9 11.3.3 Reliability test 11.10

11.4 Test records 11.10

____________________________


- 1 -

LIST OF ABBREVIATIONS % percent °C degrees Celsius A ampere ac alternating current AGI above ground installation AVR automatic voltage regulator barg bar gauge BMS Building Management System BoP balance of plant BS British Standards C&I control and instrumentation CCGT combined cycle gas turbine CCR central control room CCTV closed circuit television CO carbon monoxide CT current transformer dB decibel dc direct current DGP data gathering panels EHV extra high voltage EMC electromagnetic compatibility EN Euro Norme EPA Environment Public Authority EPC engineer, procure, construct EPR ethylene propylene rubber EWS engineer’s workstation GIS gas insulated switchgear GMT Greenwich mean time GPS global positioning system GRP glass reinforced plastic GT gas turbine HCFC single hydrochlorofluorocarbon compound HMI human machine interface HRSG heat recovery steam generator HV high voltage HVAC heating ventilation and air-conditioning Hz hertz I/O input/output IEC International Electrotechnical Commission IEEE Institute of Electrical and Electronics Engineers IP International Protection IPB isolated phase busbar ISDN integrated service digital network ISO International Standards Organisation kg kilogram km kilometre kV kilovolt LSF low smoke and fume LV low voltage m metre mA milliampere mb millibar MCB miniature circuit breaker MCC motor control centre mg milligram MICC mineral insulated copper cable mm millimetre mm2 millimetre squared


- 2 -

MV medium voltage MVA megavolt ampere MVAr megavolt-ampere reactive MW megawatt MWe megawatts electrical NCC National Control Centre Nm3 normal metres cubed NOx oxides of nitrogen O2 oxygen OCGT open cycle gas turbine ONAF oil natural air forced ONAN oil natural air natural PA public address PABX private automatic branch exchange PCS plant control system PCS plant control system PSTN public switched telephone network PTZ pan-tilt-zoom PVC polyvinyl chloride RH relative humidity rms root mean square RSO recurrent surge oscillogram RTD resistance thermometer detector SF6 sulphur hexafluoride SFC static frequency converter SMACNA Sheet Metal and Air Conditioning Contractors National Association SO2 sulphur dioxide SOE sequence of events SPN single phase neutral TEWAC totally enclosed water cooled TPN three phase neutral TV television UHF ultra high frequency UPS uninterruptible power supply UV ultra violet V volt VCR video cassette recorder VDE Verband Der Elektrotechnik Elektronik Informationstechnik e.V VDU visual display unit VOC volatile organic compounds VT voltage transformer WB World Bank WTP water treatment plant XLPE cross linked polyethylene XLPE cross linked polyethylene


- 1.1 -


1. PROJECT DESCRIPTION

1.1 General

This Specification is intended to assist the Contractor for the design, manufacture, delivery, off-loading at Site, erection, painting, setting to work, testing and attention to defects of the [ ] open cycle gas turbine power station, to be located at [ ].

The station will be constructed on a turnkey basis and shall include all equipment, work and services in order to render the power plant fully complete and functional for safe, reliable and commercial operation under all conditions and respects.

1.2 Site Description

The site is located:

[ ]

1.3 Target project start and completion

The Works are expected to commence [ ], and the plant shall be complete and ready for Taking Over having successfully completed all the tests on completion as defined in Section 11 by [ ].

- 2.1 -


2. PLANT DESIGN CRITERIA

2.1 General

This Specification requires a gas turbine power plant design that is modern, well proven, safe, economically attractive both in capital cost and running cost and offering a high availability with low forced outage rate. The plant shall be fully automated and require minimum operator intervention for normal operation. The Contractor shall comply with the Specification unless compliance would for any reason put at risk safety, reliability and economy due to deviation from standard practice of the Contractor. However, the intent of the Specification shall always be complied with.

Any deviations from the Specification shall be clearly identified in Schedule F, which shall be completed and returned as part of the Tender. The meaning of all terms is as defined in the [EPC Contract Document].

Equipment shall be designed and selected to ensure high reliability and availability of the complete plant with low forced outage rates and minimal maintenance over the lifetime of the power station, which shall be defined as 25 years.

An appropriate level of redundancy shall be included in each system; the Works shall be designed so that no single auxiliary plant failure within any gas turbine unit shall result in the total loss of the unit generating capability. In this context, it is required that with agreed exceptions, all unit auxiliaries will be provided with at least one installed spare (N+1). For the station auxiliaries, no single equipment failure shall result in any loss of station generating capability.

Prototype plant will not be acceptable, and plant that is offered with limited operating experience must be fully supported by manufacturer’s warranties and indemnities.

2.2 Unit rating

The station configuration shall be based on two open cycle gas turbine units, with a base load capacity of 240-340 MW net output at the site base reference conditions as defined in Schedule C Part 1.

The gas turbine units shall be selected to ensure that the guaranteed performance at the base reference conditions can be maintained whilst firing with the specified fuels without inlet air enhancement or power augmentation. This shall be the basis of the ‘base’ offer in the Tender.

The Tenderer may offer inlet air enhancement technology or power augmentation as alternatives to the base offer, but this shall not be part of the base offer, and shall be separately identified in the price schedules, in order that, in the event that the Owner may choose to procure such a solution, this can added. The price shall include all mechanical, electrical, I&C and civil materials and works. If inlet air enhancement technology is offered, additional performance schedules, technical data sheets and guarantees as required by the Specification shall be completed for the plant with and without this technology. The Tenderer shall include, in the above respects, full details of all additional demineralized water equipment and storage facilities and changes to the service water system, etc. that may be required as a result; again, all appropriate technical data sheets, pricing sheets, etc. shall be completed and included in the offer. The Tenderer shall prepare additional sheets and add these in the same format as provided in the relevant sections.

- 2.2 -


2.3 Site layout

The Contractor shall provide a layout generally in accordance with the conceptual site layout provided in Volume 3, conversant with good operating practise, so that maintenance access is fully available to any part of the plant.

If requested by the Owern/Engineer, the Contractor shall take account of the future possibility that the plant may be converted to combined cycle operation. The Contractor shall therefore lay out the plant accordingly with space allocation for heat recovery steam generators on a per set basis, condensing steam turbine and generators, steam turbine generator building, cooling facilities, additional switchgear, pipework, cabling, controls, etc, to form a complete, fully functional, easily maintained, combined cycle power station.]

The open cycle layout shall be based on an ‘outdoor’ type GT installation. The site layout, including plant, buildings, roads, gates, laydown areas etc shall take into consideration the requirement for heavy vehicles and cranes required for installation and future maintenance of the plant can gain access to carry out the necessary work. The site layout shall be subject to approval of the Owner/Engineer.

2.4 Plant operating philosophy

The Plant shall be designed for base load and two shifting operation. The intended operating regime for the immediate future will be base load, operating [8000 to 8150] hours per annum equating to a typical annual availability of [91 to 93] per cent. In addition, the plant shall also be capable of operating on a two-shift operating regime, based on one start per day.

Plant normal start-up and shutdown will be initiated from the main control room. The gas turbine and other BOP equipment will be operated primarily from the PCS in the main control room. Each gas turbine unit shall also have the capability to be monitored and controlled via the control systems local to each unit. The plant will be automated to reduce the manual intervention required by operations staff.

The gas turbines shall be capable of start-up, shutdown and continuous operation on the fuels as defined in Schedule A, and each gas turbine shall have cold and hot start up capability and be able to operate either individually or in parallel. The plant shall be provided with a black start capability.

2.4.1 Site conditions

Equipment shall be designed and installed to enable safe and flexible operation of the Works over the entire range of operating modes and conditions as defined in this Specification and shall operate safely and reliably over the full range of site ambient conditions listed in Schedule A of this specification.

The Contractor shall be responsible for sourcing all site meteorological data to facilitate the design of the plant, including such air sampling on site as is necessary to ensure the correct design of the gas turbine air intake filters.

- 2.3 -


2.4.2 Fuel/water supplies

Indicative analyses of the fuel and water supplies to the plant are provided in Volume 2, Schedule A for information. However, the Contractor is responsible for obtaining sufficient data regarding the fuel/water supply conditions, including analyses as necessary for his design of fuel/water treatment plant and handling/storage facilities, in order to ensure that the required quantity and quality of fuel/water is supplied to the gas turbines.

2.4.3 Grid conditions

The voltage variation on the transmission system will normally remain within the limits stated in Schedule A.

The frequency of the transmission system will be nominally 50 Hz, and will normally be controlled within the limits stated in Schedule A.

Each generation unit shall have, as a minimum, the following capabilities:

• operate continuously maintaining its active power pro rata to transmission system frequencies within the range [49.5] Hz to [50.5] Hz;

• remain synchronized to the transmission system at transmission system frequencies within the range [47.5] Hz to [52] Hz for a duration of [60] minutes;

• remain synchronized to the transmission system at transmission system frequencies within the range [47] Hz to [47.5] Hz for a duration of [5] seconds required each time the Frequency is below 47.5 Hz;

• remain synchronized to the transmission system during rate of change of transmission system frequency of values up to and including [0.5] Hz per second;

• sustained operation at the specified minimum stable generation within the range [49.8] Hz to [51] Hz.

For requirements regarding the design of the generators, refer to Section 7.1.

2.5 Seismic design

Iraq is an area of relatively high seismicity and all plant items shall therefore be designed to resist seismic loads.

For further details of seismic requirements, refer to Section 9.

2.6 Performance criteria

2.6.1 Output and heat rate

The Contractor shall guarantee the corrected net electrical power output (NPO) and corrected net plant heat rate (NPHR) at the base reference conditions as specified in Schedule C, based on the following definitions:

- 2.4 -


Net electrical power output: The net plant output is the total plant net output measured at the tariff meter, located on the HV side of the step up transformers, net of all site auxiliary loads, and transformer losses, corrected to base reference conditions.

Net plant heat rate: shall be based on the lower heating value of the fuel and corrected to the base reference conditions

The Tenderer shall also provide all necessary curves necessary for correcting power output and specific heat rate from the test conditions to the guarantee base reference conditions in his tender:

a. Variation in barometric pressure

b. Variation in ambient temperature

c. Variation in relative humidity

d. Variation of generator efficiency with power factor

e. Variation in fuel LCV and C/H ratio

f. Variation in grid frequency.

2.6.2 Plant start up

The Tenderer shall guarantee and demonstrate the time for one gas turbine to reach full load, and for the block (two gas turbines) to reach full load. Start up curves for the plant shall be provided in the Tender.

2.7 Environmental criteria

The plant shall conform as a minimum with the current World Bank guidelines, the requirements of the local environment authorities in Iraq and with all other relevant consents and regulations.

2.7.1 Noise

2.7.1.1 General

The facility shall be designed and constructed such that construction workers and operators are exposed to a minimum level of noise. The Contractor shall take appropriate steps to minimize noise exposure through equipment attenuation and procurement of inherently quieter equipment.

All noise limits specified in this document are to be evaluated as LAeq levels. This is the energy weighted average of measured noise level as averaged over a specified time period. All sound levels are expressed in terms of decibels as referenced to a sound pressure level of 20 micropascals.

- 2.5 -


The absolute limit of any measured sound pressure level anywhere in the work area shall not exceed 85 dB(A).

In locations where it is necessary for operational attendants to make routine examinations closer than 1 m to an accessible part of a running machine which is between 80 and 85 dB(A), the Owner will wish to adopt hearing protection aids. Therefore the Contractor is required to draw specific attention to portions of the plant where this situation may be encountered and fix appropriate warning labels or signs.

Noise within buildings shall comply with the limits specified in Section 9 Civil.

2.7.1.2 Construction noise

The maximum noise level caused by construction noise outside the nearest window of the nearest occupied house shall be:

Daytime 70 dB(A)

Evening 60 dB(A)

Night 40 dB(A).

Noise levels at all time periods during public holidays shall not exceed 40 dB(A).

During construction, BS 5228 shall be adopted as the approved Code of Practice in relation to noise and vibration.

Noise levels shall be limited to 80 dB(A) or lower at a distance of 1 m from all construction equipment and activities to the fullest extent feasible. If a noise level exceeding 85 dB(A) is likely to occur in any area, warning signs shall be predominantly displayed in that area, indicating that a noise hazard exists and hearing protection must be worn. Any area where noise levels could exceed 90 dB(A) shall have controlled access to prevent unprotected personnel from entering the areas.

Peak or intermittent noises such as those resulting from pile driving shall occur during daytime periods only and maximum noise levels shall not exceed 70 dB(A) at the nearest inhabited dwelling.

2.7.1.3 Far field noise during operation

The Contractor shall identify the location of the nearest residential, institutional or educational location and establish the background noise level. The noise level including background and contribution from the plant during operation shall either (a) raise background noise level by a maximum of not more than 3 dB(A) or (b) not exceed the following limits, consistent with the World Bank Guidelines:

- 2.6 -


Maximum allowable Leq (hourly) in dB(A)

Receptor Daytime (0700 to 2200) Night time (2200 to 0700)

Residential, institutional, educational 55 45

Industrial, commercial 70 70

A noise test procedure shall be submitted by the Contractor, outlining the proposed

method of noise testing, to demonstrate compliance with the stated environmental noise limits.

The on-site and environmental noise levels shall be assessed by the Contractor using his own and subcontractor’s data in order to comply with the site requirements relating to noise emissions.

The gas turbines shall be enclosed in acoustic enclosures to ensure noise limits within the building are achieved. The Contractor shall ensure that noise emissions are minimized, not only for GT plant, but also for the balance of plant equipment.

2.7.2 Emissions to air

2.7.2.1 Emissions during construction

The Contractor shall ensure that suitable site practices are employed to ensure that atmospheric dust contamination generated by the construction works do not exceed levels which could constitute a health hazard or nuisance to those persons working on the site or living nearby.

2.7.2.2 Emissions during operation

The World Bank has set emission limit for gaseous emissions from thermal power plant and gas turbines for NOx, SO2 and particulate matter. The table below presents the maximum emission limits for each pollutant based on combustion turbine units.

Maximum value Parameter

Fuel Gas Distillate fuel oil

Oxides of nitrogen* 125 mg/Nm3 165 mg/Nm3

Sulphur dioxide * 2000 mg/Nm3

Particulate matter 50 mg/Nm3

* The emission limits are referenced to 15 per cent O2, 0°C, 1 atm, and dry flue gases.

In addition the total SO2 emissions from the power plant shall be less than 0.2 tonnes per day per MWe of plant output.

The Contractor shall install appropriate abatement measures on the proposed gas turbines to comply with the NOx limits above, the details of which shall be provided in the Tender.

- 2.7 -


Continuous monitoring of NOx, SO2, CO, O2 and H2O to correct to dry flue gases shall be made from the main stacks of each gas turbine and displayed on the PCS. Any exceedances of limit values shall be alarmed.

Sampling points and safe access adjacent to the monitoring points shall be included.

Any natural gas vent stacks required shall be at a height sufficient to ensure that the concentration of gas at ground level is significantly less than the explosive limit.

Emissions of volatile organic compounds from the fuel oil tanks shall be limited by installation of appropriate VOC removal plant, such as active carbon filters.

2.7.3 Ambient air quality

The World Bank (WB) has set ambient air quality guidelines for nitrogen dioxide (NO2) and SO2. The guide values from the WB are set out below.

WORLD BANK AIR QUALITY GUIDE VALUES (micrograms/cubic metre)

Parameter Reference period Recommended ground level concentration guide value

Nitrogen dioxide Short term exposure (24 hour mean) 150

Long term exposure (annual average) 100

Sulphur dioxide Short term exposure (24 hour mean) 150

Long term exposure (annual average) 80

The plant shall not lead to either the airshed dropping into the category of poor air quality

or an increase of more than 5 mg/m3 in the annual mean level of particulates and/or SO2 for the entire airshed.

The Contractor shall be responsible for suitable stack design of sufficient height, temperature and velocity to ensure that the above ambient air quality guidelines are not exceeded in combination with all other contributing sources in the vicinity of the proposed plant.

The Contractor shall be responsible for the assessment of the existing background air quality through monitoring data, or where none is available through a modelling exercise.

2.7.4 Aqueous emissions

The discharge of any effluents during construction, including site drainage, shall be the responsibility of the Contractor who shall reach agreement with the regulatory authorities and the local sewerage authorities with regard to the detailed methods of disposal.

Aqueous emissions from the plant shall be treated and discharged in accordance with the following quality limits, consistent with the World Bank Guidelines:

- 2.8 -


Parameter Maximum, mg/l (except pH and temperature)

pH 6 to 9

total suspended solids 50

oil and grease 10

total residual chlorine 0.2

chromium (total) 0.5

copper 0.5

iron 1.0

zinc 1.0

temperature increase at the edge of the mixing zone 3°C

Aqueous discharges shall be segregated into storm drains, process effluent and domestic

sewage streams. Each shall be provided with an appropriate monitoring and treatment system to ensure that the discharge limits are not exceeded.

The effluent from the water treatment plant shall be bulked, mixed and neutralized before discharge to the site effluent tank to be provided under this Contract. Filter wash water shall also be discharged to the site effluent tank.

Any areas of the plant that may be subject to oil spillage shall be drained to an oil interceptor and the clean water discharged with the surface water drainage system.

A package sewage treatment facility shall be installed for the operational phase, sized for the number of operating and maintenance personnel.

All fuel oil and lubricating storage tanks shall be bunded to contain 110 per cent of the contents of the largest tank.

Gas turbine compressor wash effluent shall be segregated and stored at a suitable location for off-site disposal.

2.7.5 Visual impact

All reasonable measures shall be taken to minimize visual impact of the plant. Structures and buildings shall meet the standards generally accepted for a facility of this type and shall be in accordance with all applicable local and national consents relating to appearance. Final architectural arrangements shall be submitted for approval to the Owner/Engineer.

- 3.1 -


3. SCOPE OF WORK

3.1 Summary of main scope and services

This Contract provides for the design, manufacture, construction, supply, testing in works, packaging for export, shipping, transport, delivery to Site, unloading at Site, complete erection, health and safety management, painting, commissioning and putting into operation, performance and reliability testing on completion, instruction of the Owner’s personnel and obligations for the defects liability period of the gas turbine open cycle power plant.

The station will be constructed on a full design and build, turnkey basis, and it will be the responsibility of the Contractor to ensure that all equipment, scope of work and services are provided in order to render the power plant fully complete and functional for safe, reliable and commercial operation under all conditions and respects.

All material, plant and equipment shall be new and of a class suitable for the purposes specified. Equipment shall be selected to ensure high reliability and availability of the complete plant with low forced outage rates and minimal maintenance. Permanent, safe access to all items of plant shall be provided for inspection, operation and maintenance.

Unless specifically excluded from the scope of work, interconnecting cabling, pipework etc between items of equipment and plant described in this specification shall all be included under this contract, as shall the installation, testing and commissioning of the same.

Generally, the main supply will include but not be limited to the following (refer to specific sections for further details):

a. Two gas turbine generator units including

Gas turbine air inlet systems, including filtering, ducting and silencers.

Fuel pressure regulation and conditioning equipment

Gas turbine combustion system

Water injection system (if required) for NOx suppression for operation on fuel oil

On-load and off-load compressor washing system

Gas turbine generator starting system

Condition monitoring and performance system

Gas turbine generator instrumentation, control and protection system

Acoustic and weatherproof enclosures

Fire detection and protection system including, CO2 systems, gas detection system and alarm panels

Enclosure ventilation fans, ducts and silencers

- 3.2 -


Lubricating oil cooling systems

Generator air cooling system

Gas turbine exhaust system including ducting, exhaust stacks and silencers.

Continuous exhaust gas emissions monitoring equipment

Insulation and cladding

b. Auxiliary equipment and systems

All necessary auxiliary equipment and systems including, but not limited to, the following:

Fuel gas supply system required to deliver gas to the gas turbines at the required conditions including as necessary gas compressors, heaters, pressure regulation, filters, metering, condensate disposal, venting and inert gas purging system, distribution piping and valves.

Fuel oil supply system required to deliver fuel oil at the required conditions to the plant consumers, including as necessary storage, treatment, pumping, pressure control and metering, distribution piping and valves.

Water supply, metering, treatment, storage and distribution systems to deliver water at the required conditions to the plant for all raw, fire, potable and demineralized water consumers.

Waste water treatment storage, monitoring and disposal systems.

Gas turbine cooling system, comprising closed circuit circulating water system, including heat exchangers, pumps, fin/fan coolers, interconnecting piping and valves.

Fire protection and detection systems for the complete plant and buildings, including fire pumps, buried hydrant system, hydrant outlets, sprinkler systems, deluge water spray system, foam/water deluge /spray systems, hose reel and equipment cabinets, portable extinguishers, alarm panels and control system.

Instrument and service air system including air compressors, filters, driers, coolers, receivers and distribution pipework.

Heating, ventilation and air conditioning systems.

Cathodic protection systems.

Cranes and lifting equipment for maintenance of all equipment, including electric overhead travelling crane in the workshop.

All necessary interconnecting pipework and valves, including insulation, cladding and trace heating (where necessary) for all services.

- 3.3 -


Complete structural steelwork, foundation bolts and plates, anchors, guides, lifting facilities and sundries.

Facilities for storage of lubricating oils and greases, chemicals and all other consumables as required for the plant.

c. Electrical equipment

Three phase 50 Hz enclosed generators arranged for air/water cooler duty.

Generator phase isolated busbars and connections

Generator circuit breakers

Generator transformers

Unit transformers

Auxiliary and emergency transformers

Auxiliary power supplies, including MV/LV switchgear, MCCs and distribution boards

Essential supplies including batteries and UPS system.

Protective relaying and metering systems including CTs and VTs.

Lighting and small power systems and equipment.

MV and LV power, control and instrumentation, telephone and emergency cabling systems.

Earthing and lightning protection including station earthing grid

Instrumentation

Fault recording and diagnostic systems

Neutral earthing system

Black start/emergency diesel generator complete with all ancillary plant and fuel oil storage tank

d. Control and instrumentation

Complete control, protection and monitoring systems for the plant provided, including, but not limited to:

Plant control system including all necessary hardware and software for monitoring and control of the plant from the central control room

Control desks, operator workstations, engineering workstation and printers

- 3.4 -


Gas turbine local control station

Condition monitoring system for the gas turbines

PABX telephone system

Public address system

Closed circuit television and perimeter security system

Weather station providing measurement and records of ambient temperature, pressure and humidity

Tariff metering panels and equipment

All required control and instrumentation for safe, reliable and efficient operation of the plant

e. Civil Works

All civil works associated with the above equipment, including but not limited to:

Geo-technical and topographical surveys of the site, including ground pollution report.

Data collection including verification of design data provided in the tender documents

Site preparation – excavation and filling, site grading

Site access roads, car parks and footpaths

Utilities pipework

Acoustic attenuation where required to meet noise limits.

Storm, foul, oily and plant drainage systems

Utilities and underground services

Security works during construction and operational phases

Fencing and gates

Hard landscaping

Site services, (ie power, water, sewage and telephone) for the Contractor and Owner office accommodation during the construction period.

Office accommodation during the construction period for the Contractor, and the Owner Building works, foundations, structures and associated facilities:

Buildings to be included as a minimum, in the civil works as follows:

- 3.5 -


• Administration, including toilets and mess rooms, prayer, clinic and central control room

• Workshop and stores

• Fuel oil pumping/treatment plant

• Fire station and ambulance

• Fire water pump house

• Water treatment plant

• Security gatehouse

• Emergency/black start diesel generator.

Building services, including air conditioning of the local control rooms and central control building.

Foundations and associated works for:

• Gas turbine generators

• Transformer compounds

• Emergency/black start diesel generator

• Fuel gas treatment, metering and handling equipment

• Fuel oil storage tanks and handling equipment

• Service/fire water, potable and demineralized water storage tanks

• Fire fighting foam equipment

• Compressed air equipment

• Miscellaneous plant and equipment

• Service ways, ducts and trenches, pipe racks and bridges.

All necessary foundation bolts, supports, access ladders, walkways, handrails etc for the safety of personnel during plant operation and maintenance.

Bunded areas for all lubricating and other oils and chemicals

Rain shelters over all bunded areas

Sump pumps

Site sewage system.

- 3.6 -


f. General services

All necessary services associated with the above scope, including, but not limited to the following:

Quality control inspection and testing

Painting and finishing

Spare parts

Tools, lifting tackle and special appliances

Contract documents and drawings

Quality Control, inspection and testing

Operation and maintenance manuals

Training of the Owner’s staff in the operation and maintenance of the Works.

Local lifting beams and manual hoists

Special tools and maintenance equipment for all plant and equipment

All flushing facilities and flushing oils

First charge of all chemicals, lubricating oils and lubricants

Consumable spare parts (covering the Works up to Take Over).

The Contract shall include the whole of the aforementioned work which is described in or implied by the Specification and all matters omitted from the Specification which may be inferred to be necessary for the safe, reliable and efficient operation, stability and completion of the Works shall be deemed to be included in the Contract Price. All plant, equipment, materials and works shall be provided to complete the installation ready for commercial operation whether or not specifically called for herein.

3.2 Terminal points

The Contractor shall be responsible for obtaining sufficient data regarding the interface conditions for the plant, to ensure safe, efficient and reliable operation of the Works within the environmental limitations, under all operating modes and climatic conditions as defined in Section 2.

The Contractor shall be responsible for making the connections, including breaking into other systems, as necessary.

The Contractor shall assess the proposed termination points for all services and shall agree with the Owner an appropriate tie-in point and tie-in schedule. The location and schedule shall, where applicable, be designed to minimise inconvenience to other users of the systems. The

- 3.7 -


Contractor shall clearly identify in the Contract Programme the date he requires the terminal points to be available.

3.2.1 Fuel supplies

The Contractor shall be responsible for the connection of the fuel supplies to an agreed termination point located adjacent to the site boundary. The exact location of the termination point will be finalized during Contract negotiations.

An indicative analysis of the fuels is included in Schedule A for information. However, the Contractor shall be responsible for the provision of sufficient data regarding the fuel supplies for the plant, including analyses as necessary to ensure the appropriate design of treatment and handling/storage facilities to provide the requisite flow and quality of services as required by the gas turbines and other users within the site.

3.2.2 Water supplies

The Contractor shall be responsible for the connection of the water supply to an agreed termination point located adjacent to the site boundary. The exact location of the termination point will be finalized during Contract negotiations.

An indicative analysis of the raw water is included in Schedule A for information. However, the Contractor shall be responsible for the provision of sufficient data regarding the water supplies for the plant, including analyses as necessary to ensure the appropriate design of treatment and handling/storage facilities to provide the requisite flow and quality as required by the gas turbines and other water users within the site.

3.2.3 Electrical connections

Electrical power from the gas turbine generator packages shall be exported to, and be compatible with, the electrical connection provided by the Owner under a separate connection contract with the Ministry of Electricity. The HV terminals of the generator transformers will be the terminal point.

The Contractor shall establish communication protocols and liaise with the Ministry of Electricity to ensure that all appropriate safety requirements are fulfilled.

3.2.4 Communications

All connections to the public telephone network shall be the responsibility of the Contractor. The Contractor shall ensure that all communication systems used during construction and operation of the Site meet appropriate regulations and do not cause interference with any communication or electrical equipment on the surrounding site.

3.2.5 Drainage

The termination points for the drainage systems shall be sub-divided into surface water, foul water, chemical and oily water systems. Details of the drainage specification are given in Section 9.

- 3.8 -


3.2.5.1 Surface water

The surface water system should collect precipitation of the whole station into a system of underground pipes, manholes and discharge it into an existing system if available, providing sufficient capacity is available. If no existing surface water system is available, the discharge shall be arranged to a soakaway to be agreed with the Owner. The civil engineering requirements are detailed in Section 9.

3.2.5.2 Foul water

A package type sewerage treatment plant shall be provided to process the foul drainage on site. The specification of the mechanical plant is described in Section 6. Where there is an existing public foul drainage system available, the treated fluid may be discharged into the public system, otherwise the treated effluent shall be pumped to an evaporation pond which is to be supplied as part of this Contract.

3.2.5.3 Chemical and oily water

All chemical discharge from the gas turbine operation and water treatment plant must be neutralized in a neutralization pond and recorded before releasing to a public drainage system. Oil water shall be intercepted so that oil is screened and recovered before discharging cleaned water to the public system, when the specified environmental limits are met. Where no facility is available for discharge of the effluent, the chemical and oily water shall be routed to an evaporation pond which is to be supplied as part of this Contract.

3.2.6 Security fencing and access roads

The Contractor shall provide site security fencing, access roads and a main site access gate. The Contractor shall also ascertain the requirements of the Ministry of Electricity and gas supplier and provide additional security fencing, access roads and access gates to the gas supply compound and for electrical equipment compound. The detailed requirements of nominated gas supplier and the Ministry of Electricity shall be determined by the Contractor in discussions with the two organizations. Details of the civil engineering work requirements on fencing and access road are provided in Section 9. The alarm, surveillance and security requirements are detailed in Section 8.

- 4.1 -


4. GENERAL REQUIREMENTS

4.1 Programmes and progress

4.1.1 Programme requirements

The programmes supplied by the Contractor will be used by the Engineer to monitor the overall progress of the project. Primavera project management software shall be used for all programmes for the duration of the Contract. The programmes supplied by the Contractor as part of this Project shall fully interrelate design, procurement, manufacture, erection and commissioning activities. Key events shall be clearly identified on all programmes and be integrated in to the program logic.

All programmes issued throughout the Project by the Contractor shall be provided electronically in Primavera format, to allow full interrogation by the Engineer. Print or plot files will not be acceptable.

The approved programme shall be adhered to by the Contractor and shall not be changed except as agreed by the Engineer. If at any time during the execution of the project it is found necessary to modify the approved programmes, the Contractor shall inform the Engineer and submit the modified programmes for his approval. Any approval or changes to the approved programmes shall not constitute approval of an extension of the guaranteed completion date, nor any approval of claims for increases in the EPC price.

4.1.1.1 Tender programme

The tender submission shall be supported by a Tender programme (bar chart format) conforming with the outline project programme included in this Specification and in sufficient detail to indicate the Contractor’s intention for executing the Works, and must cover major items relating to design, procurement, manufacture, delivery, erection, setting to work and commissioning. The critical path shall be clearly shown. Long lead manufacturing items and the dates for placing the main subcontracts shall be identified.

Key contract, programme and interface events shall be identified in the tender programme, including dates for access data and release of terminal points, that involve the Engineer, Owner or other Contractors.

Key dates of despatch, delivery to site and completion shall be identified in Schedule B.

The tender programme shall be resourced with the site labour requirements segregated into trade categories to meet the Tender Programme.

4.1.1.2 Contract programme

The Tender Programme shall be updated to include any modifications negotiated and agreed during the period up to award of contract and shall have the detail further expanded and developed prior to being submitted for approval by the Engineer within [30] days of the Letter of Acceptance. The programme shall be of at least level 2 detail, resourced and capable of producing manning histograms for each phase of the works, covering design, procurement, manufacture,

- 4.2 -


construction, erection and commissioning. Activities of over eight weeks duration are unacceptable and shall be broken down in detail to acceptable sub-tasks. Following approval by the Engineer, this programme shall become the contract programme, and following the creation of a baseline, shall be used as the basis for measuring and reporting progress throughout the project timescale.

The approved contract programme shall be adhered to by the Contractor and shall not be changed, except as agreed by the Engineer. If, at any time during the performance of the contract, the Contractor has failed or is seen to be failing to perform the works in accordance with the contract programme, then the Engineer may direct the Contractor in writing to allocate additional resources or accelerate the works at the Contractor’s cost.

The Contractor shall be instructed to maintain his programme to reflect the current status of progress and to issue the required updated bar charts and associated reports etc, ‘S’ curves and histograms with each monthly progress report.

‘S’ curves shall be directly produced from the contract programme and be based on appropriate quantitative information. This may include, but not be limited to:

a. Number of design documents

b. Quantity of procurement components

c. Proportion of contract price for each plant area or construction activity

d. Metres of pipework erected

e. Metres of cables installed

f. Number of cable terminations completed

g. Commissioning packages.

4.1.1.3 Design schedule

The Contract Programme shall incorporate design activities that identify the sequence of work for the project and the submission of drawings, studies and reports etc. The Design Schedule shall be electronically extracted from the Contract Programme and shall contain all major documents and drawings to be submitted for review by the Engineer, their submission dates and durations for review as specified by the Engineer, and shall meet the requirements of the Contractor and other contractors engaged on the project.

4.1.1.4 Procurement and manufacturing schedule

The Contract Programme shall incorporate a Procurement and Manufacturing Schedule, which identifies as a minimum:

a. Details of suborders and target dates for placing subcontracts

b. Any detailed design required within the manufacturing period

c. Long delivery items.

- 4.3 -


d. Information to be supplied by the Engineer/Owner submission dates.

The Procurement and Manufacturing Schedule shall be electronically extracted from the Contract Programme and shall be in sufficient detail to enable the work to be adequately progressed. This schedule shall meet the requirements of the Contractor and other contractors engaged on the project.

4.1.1.5 Preliminary Construction Schedule

The Contract Programme shall incorporate a preliminary construction schedule, which should identify in sufficient detail the Contractors intended construction strategy. The programme shall satisfy the following criteria:

a. Contain full details of all civil/mechanical/electrical terminal point release requirements.

b. Identify when services are required for commissioning purposes.

c. Include an outline setting to work and commissioning schedule.

The Preliminary Construction Schedule shall be electronically extracted from the Contract Programme.

4.1.1.6 Construction Schedule

Within 90 days of Contract Award, the Contract Programme shall incorporate a detailed level 3 Construction Schedule, expanding the detail in the Preliminary Construction Schedule and be electronically extracted from the Contract Programme. In addition to the detail outlined in 4.1.1.5, this schedule shall be in sufficient detail as agreed by the Engineer, to enable the work to be adequately progressed and monitored. This to include long duration activities of over 30 days to be broken down into sub-tasks of no more than 30 days duration. This schedule shall meet the requirements of the Contractor and other contractors engaged on the project.

4.1.1.7 Commissioning schedule

During the progress of the works, the Contractor shall develop the outline setting to work and commissioning schedule into a detailed level 3 Commissioning Schedule, in sufficient detail to enable the work to be adequately progressed. Activities of over two weeks duration are unacceptable and shall be broken down into acceptable sub-tasks. This schedule shall be electronically extracted from the Contract Programme and submitted to the Engineer for approval 3 months prior to the start of any commissioning activities and shall be approved not later than 1 months before the start of any commissioning activities. This schedule shall meet the requirements of the Contractor and other contractors engaged on the project, and shall be integrated with the contract programme.

4.1.2 Progress reporting

Monthly progress reports shall be produced by the Contractor and submitted to the Owner from the commencement of the Contract. The format is to be approved by the Engineer. They shall be submitted within one week of the report cut-off date to be agreed during negotiations. The report

- 4.4 -


shall address design, procurement, manufacturing, construction, setting to work and commissioning issues. The reports shall include but not be limited to the following:

a. Executive summary.

b. Schedule of forecast and actual key events.

c. Three month look-ahead programme (extracted from the Contract Programme).

d. Progress to date in narrative format.

e. Areas of concern and details of corrective action being taken.

f. Actual resources against planned.

g. Updated ‘S’ curve.

h. Contract programme updated to show progress achieved. Programme progress updates shall also be provided in the form of a fully working Primavera electronic file, which will allow analysis by the Engineer. Electronic print or plot file are not acceptable.

i. Planning and consents.

j. Safety issues and industrial relations.

k. Colour photographs of progress in digital format. Each set shall comprise a total of 20 colour photographs, individually marked with the date taken, a description of the subject and the direction of view.

l. Contract financial status.

The Contractor may be required to include additional schedules and charts considered necessary by the Engineer to adequately monitor the Contract.

Hard copies of progress reports are to be issued to the Engineer and Owner in accordance with Schedule E. An electronic copy shall also be submitted to both the Engineer and the Owner.

Following mobilization at site, the Contractor’s site office shall submit weekly progress reports to the Engineer in accordance with Schedule E. The report shall summarize site activities, indicate numbers of the various classes of workmen employed on site, the plant and equipment on site and record any areas of concern and details of corrective action being taken. Daily activity reports shall also be provided summarizing the main activities to be undertaken each day, noting any special activities that require witnessing, together with full particulars and details of all obstructions, modified or additional work, incidents and the number of men employed in each of the several portions of the work in progress, in accordance with Schedule E.

- 4.5 -


Access to the Contractor’s or subcontractor’s works shall be granted to the Engineer at any reasonable time for the purposes of ascertaining progress. The Engineer shall also have access to the Contractor’s daily activity reports.

The Engineer may request the Contractor to provide additional reports when in his opinion they are warranted.

Where there is an agreement to pay by time and material rates, the Contractor shall keep records of labour, materials and equipment. Such records shall be valid only when signed by both parties.

For work of a disputed or uncertain nature, sheets shall be signed by both parties as an agreed record of work done. The sheets shall be annotated “For record purposes only” and shall not imply any commitment concerning payment.

4.2 Design and standardization

The Works shall be designed to ensure satisfactory operation in which continuity of service is the first consideration and to facilitate inspection, cleaning and repairs. All equipment supplied shall be designed to ensure safe and satisfactory operation under the atmospheric conditions prevailing at the Site, and under such variations of load and pressure as may be met with under working conditions. In doing so the Contractor shall be responsible for and shall carry out HAZOP studies or other studies deemed necessary by the Engineer as part of the design process. The Works and all equipment and materials forming part of this Contract shall comply in all respects with any relevant statutory regulations, by-laws or orders currently in force where the Plant is to be erected.

Although the Works shall generally comply with international standards, any instruction in this Specification that a particular aspect of the Works shall comply with a named code or standard shall take precedence, and that particular aspect of the Works shall comply with the named code or standard. International standards are those standards such as BS, IEC, ISO, ANSI/ASME, API, NFPA, JIS, TRD, DIN and EN etc which are in common use throughout the world for this type of application.

In the event of any conflict in standards, the hierarchy of standards shall be as follows, with the standards occurring first in the list taking precedence over any standards later in the list:

a. Standards named in the Specification

b. International Standards

c. Other standards approved by the Engineer.

The Contractor may offer Works which comply with international standards, or internationally recognized codes or standards, which differ from those specified. However the Contractor may offer Works which comply with the different standards or codes only if he is able to demonstrate to the Engineer’s satisfaction that the Works offered are equal or superior to that which would have resulted had the specified code or standard been used. This substitution of codes or standards for those specified will only be acceptable if the manufacturing organization in question has extensive experience with the alternative code or standard offered. If requested to do so by the

- 4.6 -


Engineer, the Contractor shall supply to the Engineer, at his own cost, two copies in English of the relevant code or standard which he proposes to substitute for that specified.

The Contractor shall be responsible for ensuring that all standards used are current, the use of superseded or obsolete standards is unacceptable. The ruling date for current standards are those in place at the time of Contract signature.

The Contractor shall be responsible for submitting all statutory calculations for the third party verification and for all other calculations required by the Engineer.

The International System of Units (SI) shall be used in connection with this Contract and the provisions of ISO 31 and ISO 1000. All materials, fittings, components, items of plant and equipment supplied for incorporation in the Works shall be standardized accordingly. If, after making diligent enquiries, the Contractor is unable to obtain an item standardized in SI units, written approval shall be obtained from the Engineer to supply non-standard material.

The principal units shall be as follows:

Parameter Units Remarks

Pressure bar absolute All calculations relating to plant performance

bar gauge All pressure gauges

millibar Gauges below atmospheric pressure

Temperature °C

Volume l (m3) litre

Mass kg (t) (metric tonne)

Flow – mass kg/s (t/h)

Flow volume l/s (m3/h)

Flow – gas kg/s (Nm3/h) (measured at 0°C 1.013 bar a)

Rotational speed rpm

Power kW

Enthalpy kJ/kg (MJ/Nm3)

Vibration mm (amplitude peak to peak)

Head m of H2O (mm Hg)

Heat rate kJ/kWh

Emissions level kg/m3

Alternative units indicated in brackets, may be used with the agreement of the Engineer.

SI units shall be used in all correspondence, documentation, calculations, drawings, measurements etc. If reference has to be made to non-standard items, the SI units shall be quoted followed by the non-standard units in brackets.

- 4.7 -


The Contractor shall standardize mechanical and electrical equipment as well as instrumentation. Corresponding parts shall be made to gauge and shall be interchangeable wherever possible. When required by the Engineer the Contractor shall prove this quality by actually interchanging the various parts.

Particular attention must be paid to internal and external access in order to facilitate inspection, cleaning and maintenance. The Works shall be arranged such that each major item, plant, or group of minor plant items, can be safely isolated from all hazards for maintenance, if necessary, whilst the remainder of the plant remains in service.

The design shall conform to the best current engineering practice. All plant shall be of the manufacturer’s standard design, provided that this design is in general accordance with the Specification and shall use components proven to be satisfactory by previous experience.

The design dimensions and materials of all parts shall be such that they will not suffer damage as a result of stresses under the most severe service conditions. The materials used in the construction of the Plant shall be of the highest quality and selected particularly to meet the duties required of them. The plant shall be designed and constructed to minimize corrosion. Workmanship and general finish shall be of the highest class throughout.

All equipment shall be designed to minimize the risk of fire and damage which may be caused in the event of fire.

The equipment shall also be designed to prevent ingress of all vermin, accidental contact with electrical live parts and minimize the ingress of dust and dirt.

The Contractor shall provide the services of an approved Classification Society or Insurance Inspection Company subject to the Engineer’s approval and which shall include:

a. the certification of designs and drawings and the checking of scantlings of the components of pressure and vacuum containing parts

b. the certification of designs and drawings of lifting equipment and any other items of plant and equipment which in the opinion of the Engineer requires insurance inspection

c. the inspection and certification that all such components and plant items are manufactured, constructed and tested in accordance with the accepted standards

d. the inspection and certification of pressure or vacuum containing parts, lifting equipment, welding and associated non-destructive testing of such welding, during erection and commissioning on Site.

All certificates shall be distributed in accordance with the requirements of this Specification.

- 4.8 -


4.3 Drawings and documents

4.3.1 Drawings enclosed with the Specification

A list of the drawings to be read in conjunction with the Specification is given in Volume 3. The drawings issued by the Engineer with the Tender Specification and forming part of the documents for tendering purposes are intended to be descriptive of the character of the Works and used in conjunction with the requirements of the Tender Specification and shall in no way limit the responsibility of the Contractor to supply all plant and equipment and services necessary to provide for a complete and functional complex. Any omission from both drawings and the Tender Specification or express reference to any detail or work necessary and obviously intended shall not relieve the Contractor of his responsibility to include that detail or work.

The sizes of the buildings shown on the Tender Specification drawings are approximate, since the actual size will depend on the size and shape of the plant, equipment and materials forming the Contractor’s Works and the space required for installation, maintenance, lay down, storage, access, etc.

The drawings depicting Civil Works do not portray exact requirements but are intended to be an indication of the type of work required.

When measurements are affected by conditions already established, the Contractor shall take and be responsible for field measurements notwithstanding any information given on the Tender Specification Drawings.

4.3.2 Schedules

The following technical schedules, contained in Volume 2, have been prepared on IBM compatible computers using Microsoft Word and Excel, and are available via DC ROM.

Schedule A Site particulars

Schedule B Dates of despatch, delivery to site and completion

Schedule C Manufacturer’s technical particulars

Schedule D Suppliers of materials, manufacturers, places of manufacture, testing and inspection

Schedule E Drawings and documentation

Schedule F Variations from Specification

Schedule G Tests and inspections

Schedule H List of recommended and optional spare parts

Schedule J List of special tools and equipment

- 4.9 -


The Tenderer is required to complete the required technical schedules (including prices, where applicable) and return these via CD ROM with the completed schedules of their Tender. A signed print out of the schedules shall be used as original. The completed schedules have precedence over the disks.

The details provided in Schedule C1 – Manufacturer’s Guarantee Particulars shall take precedence over any other technical information provided in the Tender.

Schedule F (Deviations from Conditions of Contractor or from Specification) has been prepared on Microsoft Excel on the CD ROM. Tenderers are required to complete and return all Comments and Deviations on a CD using the format as provided, ensuring that all items are referenced to the relevant Volume/Section and Page of the Specification, and are uniquely numbered.

Unless a specific variation is detailed in Schedule F, the Tenderer shall be deemed to comply fully with the requirements of the Specification.

4.3.3 Drawings and documents to be submitted by the Tenderer

A list of the drawings and documents to be included within his Tender is included in Schedule E.

4.3.4 Drawings and documents to be submitted by the Contractor

A list of the drawings and documents to be submitted by the Contractor during the Contract implementation stage is specified in Schedule E. The Contractor shall also submit any further drawings or documents as may be reasonably required by the Engineer, during the design and construction of the Works. The Contractor shall prepare and submit to the Engineer review drawings (including dimensioned general arrangement, layout and detailed design drawings), and documents (including schematics, Process and Instrumentation Diagrams (P&IDs), data sheets, descriptions, plans and schedules) of all the plant and equipment specified in the Specification. Drawings and documents already submitted by the Contractor and reviewed by the Engineer, and such drawings and documents as shall be thereafter submitted by the Contractor and reviewed by the Engineer, shall not be departed from without the written instructions of the Engineer.

Copies of each drawing, calculation and data shall be submitted in accordance with the programme given in the Schedule of Contract Drawings. If the Contractor requires early review of any drawing or document to avoid delay in the delivery of the Contract Works, he shall advise the Engineer to such effect when submitting the drawing or documents. The sequence of submission of items shall be such that all information necessary for assessing each item is available at the time when received. In all cases, the drawings or documents shall be submitted in sufficient time to permit modifications to be made if such are deemed necessary by the Engineer without delaying the delivery of the Contract Works.

As soon as practicable, and not later than 20 working days after receipt, the Engineer will advise the category of the drawing as “Reviewed”, “Reviewed as Noted”, or “Returned for Correction”, as may be appropriate. The categories “Reviewed” and “Reviewed as Noted” authorize the Contractor to proceed with manufacture of the equipment covered by such drawings subject to the corrections, if any, indicated thereon. Where prints of drawings have been “Returned for Correction”,

- 4.10 -


or “Reviewed as Noted” the Contractor shall make the necessary revisions on the drawings and submit further copies for approval in the same procedure as for the original submission of drawings.

Drawings shall be submitted for review at all stages of revision. The Contractor shall supply copies of each drawing for revision as detailed in the appropriate Schedule.

Following review, additional copies shall be provided for use at Site as required by the Engineer. .

All dimensions marked on drawings are to be considered correct, although measurements by scale may differ there from. Detailed drawings reviewed by the Engineer are to be acted upon where they differ from the general drawings.

Drawings showing the physical location of all devices and a plot plan showing the location of all equipment shall be provided.

Drawings shall not be “typical” but shall actually represent the equipment provided. Drawings shall be corrected to “as built” before final unit acceptance.

Approval of drawings shall not relieve the Contractor of any of his obligations under the Contract.

All legends and notes on drawings provided by the Contractor shall be in the English language. All drawings shall be dimensioned in millimetres (or metres) and drawn to one of the preferred scales quoted in Table 7 of BS Publication PD6031 and on paper of the appropriate size from the International series of A sizes.

4.3.5 Drawings and document format

Each drawing and document shall bear a unique drawing/document number. Individual items of equipment forming a part of a drawing shall be clearly identified by means of tables or other approved methods.

Each drawing shall incorporate the following information:

a. Location.

b. Drawing title (shall contain no abbreviations).

c. Original drawing sheet size ie A0, A1, A2, A3 or A4.

d. Drawing status.

e. Drawing number with provision for sheet and revision suffixes.

f. Drawing date.

g. Identity of persons carrying out the draughting, checking and approval.

- 4.11 -


h. Scale or not to scale.

i. Project/contract number.

j. Revision.

k. North point on geographically related drawings.

The Owner’s information shall be in the form of the Owner’s Drawing Information Box. This box shall be located at the bottom right-hand corner of the drawing.

Documents submitted for review or approval shall incorporate the following information:

i. Document title (shall contain no abbreviations)

ii. Document status

iii. Document number

iv. Identity of person carrying out the preparation, checking and approval

v. Project/Contract number

vi. Revision.

4.3.6 Drawing sheet numbers

All drawings shall have a two digit sheet number.

Where only one sheet exists the sheet number shall be 00, where more than one sheet exists the sheets shall be numbered from 01 to 99 accordingly.

4.3.7 Drawing and document revision

All drawings and documents shall have a two digit revision number and all changes shall be clearly indicated by the addition of the following: appropriate revision number, revision date; identity of persons carrying out the draughting, checking and approval; concise details of the modification.

First issues have a revision status of 00, subsequent changes shall increase the revision status from 01 to 99 accordingly.

The change of drawing status shall result in a revision increase of one, whether there are changes to the drawing or not.

- 4.12 -


4.3.8 Drawing and document status

Status definitions shall be used on all drawings and documents. The status shall not be part of the drawing or document title. The definitions are as follows:

a. For approval

b. For review

c. For information (for non-project/contract drawings)

d. For tender purposes

e. For construction (includes manufacturing)

f. As built and records.

All revisions of drawings shall be submitted in the following formats as detailed below:

i. A contract drawing list giving the Contract number, manufacturer’s number, sheet number, revision and title of each drawings.

ii. Paper prints of each drawing - full size.

iii. Paper prints of each drawing - A3 size.

iv. AutoCAD ACAD 2000 drawing file.

v. Drawings in PDF format.

The Contract drawing list shall be submitted by the Contractor for review by the Engineer who will indicate thereon the Owner’s requirements. On completion of commissioning, all drawings shall be updated and marked ‘as built’. These shall be supplied as final record drawings.

The AutoCAD ACAD 2000 drawing files referred to above shall be imported and exported on media such as Digital Linear Type (DLT) or CD. Each media shall be clearly labelled and accompanied by a transmittal sheet showing all file details.

Where the file format is restricted, the transmittal sheet shall clearly show how filenames relate to drawing numbers.

4.4 Operating and maintenance instructions

The Contractor shall supply complete and detailed Operating and Maintenance manuals in English covering the operation and maintenance of the plant and equipment as required by the Contract.

The contents of the operating and maintenance instructions, together with all drawings, illustrations and diagrams shall refer specifically to the plant and equipment being supplied under the

- 4.13 -


Contract, and shall be specially prepared where necessary. General instructions referring to a range of equipment is not acceptable.

Operating instructions shall detail all integrated plant normal pre-start checks, starting up, running and shutting down procedures, for the various modes of operation of the plant from cold, warm or hot conditions, emergency operating procedures and any precautions recommended to prevent plant deterioration during periods of non-operation. Operating instructions shall cover local/remote and manual modes of operation and shall also include action on receipt of alarms.

The Contractor shall prepare a comprehensive commissioning schedule for each plant item and check lists to record the completion of these activities. Copies of all settings and/or calibrations of instruments and controls, pressure switches, trips and alarm settings confirmed and recorded in the commissioning schedules shall be forwarded to be included in the Operating Instructions.

[Five] sets of draft copies of the manuals shall be submitted to the Engineer for review [6] months before commissioning commences. They shall be submitted as complete texts. In the event that amendments or alterations to the draft manuals are required, the Contractor shall submit revisions for review without delay so that the final documents can be supplied within the date specified. [Eight] sets of the final documents shall be submitted within 4 months after the Taking Over Certificate.

The whole of the operating and maintenance instructions shall be securely bound in approved covers and provided with an index for easy reference.

The O&M manuals shall be provided in paper hard copy and in electronic copy on CD-ROM to a standard document reader format (ie Adobe Acrobat Reader).

The instruction manuals shall conform to the following format:

a. Index

The index system shall provide rapid and easy access to particular subjects, drawings and illustrations. It should include a master index and a sub-index to each main section of the manual.

b. Description

This section shall include basic data on the Plant.

i. Descriptions of the Plant both for individual items and for the systems into which items are assembled.

ii. Drawings sufficient for the understanding of descriptions.

iii. Flow sheets or single line and block diagrams which explain the functioning and logic of the system. Where related systems are shown on composite diagrams, individual systems shall be identified by colour, or coding as agreed.

- 4.14 -


iv. Schedules which assemble references to items of a like kind, eg valve schedules, piping schedule, operational limit schedule, switchboard outline schedule, etc.

v. Data sheets which assemble in a concise format relevant technical details of a plant item or system. The purpose of a data sheet is to provide quick reference to the essential facts omitting all reference to general descriptions, operating or maintaining principles and instructions.

c. Operation

This section shall include basic step-by-step instructions on how to operate the Plant both with regard to individual items and to systems under all patterns of normal and abnormal conditions. The instructions shall include reference to the applicable operation limits.

Precautions and warnings relative to the safety of life and equipment shall be included where relevant.

d. Maintenance

This section shall include the following:

i. Build-up and assembly of systems and description of plant items.

ii. Schedule of equipment giving manufacturer’s name, the make/model No/catalogue No and parts list including any special spares ordering instructions. Spare parts catalogues shall be provided for the various items of equipment supplied.

iii. Routine maintenance schedule.

iv. Preventative maintenance and schedule of inspections.

v. Details necessary to carry out overhauls.

vi. Details necessary to locate and rectify faults.

vii. Details necessary to set up, test and adjust plant systems and plant items. To include as a minimum, fuel systems, cranage, ventilation, fire protection, water treatment plant and compressed air equipment.

viii. Spares schedule.

ix. Schedule of recommended lubricants.

x. Sectional drawings of major items of plant, steam turbine, air cooled condensers, pumps, valves, etc with dismantling instructions.

- 4.15 -


xi. As built copies of all relevant drawings corrected as necessary to incorporate any late modifications.

xii. Plant layout drawing.

xiii. Schematic diagrams and general arrangement drawings of “as-built” control panels.

xiv. Wiring and cable diagrams.

xv. Plant equipment and performance curves.

xvi. Lifting gear register.

The final records shall include the construction and pre-commissioning data dossier with signed record sheets.

e. Spare parts

This section shall comprise the definite and optional spares as required by the Owner and the spares as recommended by the Tenderer. Details and full ordering procedures for each item of main plant, auxiliary plant, electrical and C&I equipment and vendor equipment and shall include:

i. Spare part lists together with referenced sectional drawings from which the manufacturers descriptive name and part number can be clearly identified for ordering purposes.

ii. Clear details of spare part suppliers address, spare part ordering procedure and including all appropriate plan item reference numbers including serial numbers, type reference numbers, original order numbers, etc as required for the immediate and correct supply of spare parts from various original plant suppliers.

In this context the term “suppliers address” means the sub-vendor or original equipment manufacturer. It will not be acceptable for the Contractor to nominate himself as the supplier of a spare part unless he manufactures the particular equipment, or it is manufactured by a third party in accordance with the Contractor’s own manufacturing drawings.

iii. A list of spares for each type of overhaul/inspection shall be provided.

Note: where spare parts are not available and full item replacement is necessary this fact is to be advised and the appropriate ordering details provided as defined above.

For spares that are available from a multitude of sources (eg seals, “O” rings, gaskets, nuts, bolts, etc the Contractor shall supply details of the sizes, standards and materials used.

- 4.16 -


Details shall be provided of any special storage requirements or limitations on storage life for spare parts.

f. Plant preservation schedule and methods

This section shall cover the procedures for shutting down plant. Preservation during hibernation and re-starting of plant.

g. Manual production

Accepted abbreviations of units of measurement are permitted in the text and illustrations. A list of the abbreviations the Contractor proposes to use in the text and schedules is to be approved before work begins on the manuals. As a guide it may be taken that abbreviations of terms will be permitted only where they are in common use and readily understood, eg ac, dc, OCGT.

Drawings and diagrams shall, wherever practicable, be reduced to a convenient size, eg A3, and bound into the manual. The reduced size drawings and diagrams shall be completely legible and suitable for reproduction. Drawings which are referred to several times in the text shall be either of the “fold out” type or visible when referring to other parts of a manual or be repeated as necessary. Throw-clear drawings are to be included at the back of the relevant subsections, and their locations noted in the Section drawing index.

Detailed engineering drawings necessary for maintenance and mentioned in the text but not included in the manual because of size reduction difficulties, should nevertheless be listed in the drawing index. The words “NOT INCLUDED” must be entered against them. Drawings are to be identified at the bottom right corner by title and number.

Black on white line drawings should be used wherever possible, using line shading, and cross hatching as necessary for clarity. Multi-colour and half-tone drawings using shading techniques, eg air brush, should only be used in preference to line drawings where the additional information conveyed justifies the effort and cost. Isometric and perspective illustrations are preferred to engineering (orthographic) drawings, although engineering drawings may be included if they are more suitable due to the size and complexity of a particular item of equipment. Where engineering drawings are used, clarify of detail necessary to support the text shall be retained and in addition all irrelevant information such as unnecessary dimensions, manufacturing information, borders, centre lines, etc should be removed. All drawings shall be clearly marked by legend.

The manuals shall be produced as a book or books, with page size international A4, bound into strong durable covers inscribed upon the front generally in the form of the title page to the Specification, except that the references to the contents will be replaced by “Operation and Maintenance Instructions”. Contractors standard pattern covers may be used, subject to the Engineer’s approval.

- 4.17 -


The name of the main Contractor but not that of any subcontractor may also be inscribed upon the cover after the description of the Plant.

The name of the Owner, the title of the project and Contract number followed by a brief description of the Plant (eg turbo-generator plant, etc) shall be inscribed upon the spine of the cover. If the text is bulky it shall be divided into conveniently sized volumes, and each shall be marked with the appropriate volume number.

4.5 HAZOP studies

The design of the plant shall take into account good engineering practice with an emphasis on safe and efficient operation and maintenance practices. The Contractor shall perform hazard and operability (HAZOP) studies to demonstrate to the Owner and the Engineer that where possible all risks concerning safe and efficient construction, operation and maintenance have been identified and solutions implemented to eliminate such risks.

In the event that the HAZOP studies identify residual risks which cannot be avoided, the Contractor shall incorporate measures in the design, implementation and project documentation (O&M Manuals) to ensure that the effects of the risk is mitigated and the likely effects on the operating personnel, the environment etc are minimized. The Owner/Engineer shall be provided the opportunity to participate in the HAZOP reviews.

4.6 Places of manufacture, testing and inspection

The manufacturers and the places of manufacture, testing and inspection before shipment for the various portions of the Works shall be as stated in Schedule D.

As soon as practicable after entering into the Contract, the Contractor shall, having obtained the Engineer's consent in accordance with the Conditions of Contract, enter into the subcontracts he considers necessary for the satisfactory completion of the Works.

4.7 Packing and marking on packages

All apparatus shall be carefully packed for export shipment and storage at site in such a manner that it is protected against all climatic conditions. The packing cases and packing materials are included in the Contract and shall become the property of the Owner.

Key equipment shall be transported with monitoring dew meters within each transport case. Gas turbines, generators, and black start diesel generator set shall be transported with monitoring shock meters.

4.8 Training

The Contractor shall provide training for the Owners operating staff, and give the price in his Tender, as required in the EPC Contract. The price shall assume for [100] man weeks of off-site training with the following details.

- 4.18 -


4.8.1 General

The Works shall include for separate training sessions for operating and for maintenance staff. Such training shall be at the Contractor’s expense and to an agreed pre-scheduled programme. The level of training shall be suitable for each member of staff to ensure individual competence in the operation, troubleshooting, maintenance, administration and management of the Power Station. The Contractor will be responsible for the planning and co-ordination of the training in conjunction with the Owner. A fully detailed training programme with dates shall be submitted to the Engineer for approval [4] months after award of the Contract. The training shall be ongoing during the testing and commissioning period so as to ensure that operating and maintenance instructions have been given on all commissioned plant items handed over to the Owner.

The site training shall consist of programmes and scheduled training provided by the Contractor. Formal classroom training supported by audio and/or visual aids and to a larger extent practical “hand on” exercises with the equipment supplied under the Contract shall be part of the on-site training and shall cover:

a. Basics - open cycle operation theory plant descriptions main components of the Works

b. Operation - control system operating procedures start up/shutdown full load/partial load efficiency and heat balance emergency operations abnormal operations

c. Mechanical maintenance - inspection tasks, planning minor maintenance on mechanical plant

d. Electrical maintenance - inspection tasks, planning minor maintenance work on the generator and exciter minor maintenance work on electrical equipment minor maintenance work on instrumentation

e. Trouble shooting - main mechanical components generator and electrical equipment control and protective relay equipment

f. Control and instrumentation systems

- operation maintenance and testing configuration fault finding

4.8.2 Content of training

The training shall generally comprise a combination of formal instruction on site and/or at major equipment manufacturer’s training facilities, and on the job “hands on” training and familiarization during the construction, commissioning and initial operation periods on site. Where

- 4.19 -


training at manufacturers’ works is proposed the benefits of using such off site training facilities must be clearly identified by the Contractor.

The site training shall consist of training by the equipment manufacturers and by the Contractor. Allowance shall be made for formal classroom training as part of the on-site training. All formal training shall be carried out by dedicated training engineers who must be familiar with the specific plant installation.

The Contractor shall make available qualified and experienced full time instructors competent in presenting comprehensive courses covering the operating and maintenance of all items of the plant. Sufficient numbers of the instructors shall be fluent in the English language to enable the training to proceed logically and be fully beneficial. All training costs and expenses, training materials, manuals, and use of training facilities costs shall be borne by the Contractor.

Operation of the plant during commissioning will be carried out by the station personnel, as far as possible, under the control of the Contractor’s personnel who will retain at all times responsibility for commissioning and operation of the plant. Hands on training and familiarization during commissioning shall include control room and local control station operation, start-up, shut down, all design modes of operation, routine plant changeover and test, routine maintenance and fault finding.

The staff shall partake in as detailed a study of the plant and equipment accessories systems, operating procedures, maintenance requirements, O&M manuals and drawings as is necessary for the continuous, safe, efficient and economic operation of the plant and shall receive theoretical and hands-on training on all of the systems control, protection, operation and general plant specific troubleshooting procedures.

The training shall be directed at competent operations and maintenance staff who will ultimately operate and carry out routine maintenance of the plant following take-over. The curriculum vitae for each supervisor and instructor shall be submitted to the Engineer and Owner for approval before he is employed n the site. The Tenderer shall show in the Schedules the period, number and category of staff proposed for this service.

All training shall be programmed, scheduled and co-ordinated by a training specialist whose sole responsibility will be to ensure that all the station staff have had sufficient technical training and on the job training to operationally manage the station to the standards of a reasonable and prudent operator. The programme shall include for recorded assessment of trainees, trainers, and the extent/adequacy of the training programme. Assessment records shall be submitted to the Owner on completion of each training module. Where the assessments indicate that the performance of the trainer and or adequacy of the content of a training module is unsatisfactory the Contractor will be required to propose remedial action. Such action will be at the Contractor’s expense.

4.9 Spare parts

The Contractor shall provide with its tender a complete priced list of spare parts, in Schedule H. The list shall be developed on an estimated usage basis and supporting data from existing plants shall be provided to substantiate the spares holding and usage proposed.

- 4.20 -


The priced list of spares shall include a recommended stockholding to cover all initial inventory, planned maintenance and strategic reserves up to and including the first major overhaul.

The Contractor shall provide all the commissioning consumables and spares up to take over of the works, together with consumable spare parts for the first [two] years of operation.

4.10 Special tools and lifting devices

The Contractor shall supply a complete set of any special tools and other equipment necessary for the dismantling, work storage, re-erection and adjustment of any part of the plant. Tools shall be provided in new condition, adequately labelled to their use and contained in stout and suitable padlocked boxes.

Any special lifting devices/slings required shall be provided and clearly marked by embossed labels which show safe working loads. Test Certificates shall be provided where applicable.

Suitable lifting equipment shall be provided to facilitate removal and maintenance of plant and equipment. Lifting devices shall be designed in accordance with the latest editions of the relevant ISO standard or equivalent. All electrical and mechanical functions shall be tested before despatch from the manufacturer’s works. Operational and overload tests shall be carried out on site.

Suitable lay down areas and methods of retrieving the equipment should be included to support the integrated approach to the crane facilities.

4.11 Warranty engineer

A warranty engineer shall be located on site for [one] year following the date of Takeover. The warranty engineer shall have not less than eight years experience of power plants similar to the Facility and shall act proactively to ensure the best performance and availability of the plant is achieved. A CV for the proposed engineer shall be submitted for approval prior to him taking up the appointment. The approval shall not be unreasonably withheld.

The Contract shall include for all travelling, accommodation and subsistence costs of the engineer and for his replacement by a similarly experienced engineer during periods of leave or long-term sickness. The replacement engineer shall be to approval. Such approval shall not be reasonably withheld.

The warranty engineer shall be available on site between 0800 – 1700 hours Saturday to Thursday, and available for callout duty outside of these hours.

The warranty engineering shall be responsible for the following throughout the warranty period:

a. Ensuring that the O&M operator is operating and maintaining the entire plant in accordance with the manufacturers’ instructions, and notifying the Owner and the O&M operator of any shortcomings.

b. Providing technical advice and support to the O&M operator.

- 4.21 -


c. Monitoring the performance and availability of the plant.

d. Assisting with troubleshooting.

e. Acting as liaison with the Contractor’s head office for the clearance of any defects existing on Takeover or occurring during the warranty period, to ensure that they are cleared promptly.

The Owner will monitor the performance of the warranty engineer. Should his performance be unsatisfactory, the Contractor shall provide a replacement engineer to the satisfaction of the Owner.

- 5.1 -


5. SITE DETAILS AND SAFETY REQUIREMENTS

5.1 Location of Site, access and use of Site

The Site conditions are given in Schedule A and drawings showing the location of the Site are included in Volume 3.

The Contractor shall inform himself fully as to all transport facilities, requirements and loading gauges to ensure that all equipment as packed for transport shall conform to these limitations, and shall be responsible for all damage to roads, bridges, etc during transportation.

The location of the laydown parking and construction areas will be the responsibility of the Contractor. The Contractor shall provide his own hardstanding storage, working areas, access ways, any roofed accommodation and security arrangements where necessary. Such facilities shall after the agreement of the Owner/Engineer be removed from Site on completion of the Contract.

The Contractor shall, and at his expense, take precautions to keep all existing and new temporary and permanent roadways clear of any spillage from his traffic. All such spillage, which occurs, shall be cleared immediately, including excessive earth or other materials brought in on wheels or tracks of the traffic.

The Contractor shall confine his labour, material, plant and equipment to within the designated areas of which he has been given possession.

No lands or other places which are the property of the Owner shall be used except in accordance with the instructions of the Owner/Engineer. The Contractor shall at any time move any vehicle, temporary work, plant or other obstruction within his control that may be required to be moved by the Owner/Engineer and the Contractor shall move any such vehicle, temporary work, plant or obstruction promptly on the instruction given by the Owner/Engineer, all at the Contractor’s own cost.

The Contractor shall maintain access for the inspection, operation and maintenance of any of the Owner’s/Engineer’s premises, plant or works which are within the contract site boundaries.

The Contractor shall maintain the whole of his operations in a clean, tidy and safe condition and shall arrange his materials in an orderly manner.

All rubbish, waste materials, debris and the like shall be regularly and systematically cleaned off the working areas as it accumulates and deposited in collecting points from which the Contractor shall regularly dispose of waste materials.

The Contractor shall ensure that the site and adjoining lands belonging to third parties are kept free from construction materials of any kind arising from the Works and that no damage occurs to third party property.

On sites which are in use, or have been in use, or sites in which services may cross, the position of any existing services in or near the proposed work area shall be pinpointed as accurately as possible by means of site plans. The Contractor shall use locating devices to confirm the position of the services.

- 5.2 -


Hand held power tools and mechanical excavators shall not be used within the vicinity of existing underground services.

Any pipe or cable which is uncovered shall be treated as live unless proven otherwise. Upon completion of the work in a particular area, any warning tiles or tapes shall be replaced.

5.2 Site facilities

The Contractor shall provide portable office Site accommodation for his own and sub-Contractors staff, which shall conform to the requirements of any local and statutory authorities, for the area in which the work is situated.

Site accommodation and arrangements shall be subject to the approval of the Owner/Engineer in all respects.

The Contractor shall establish and operate a site security system, all staff employed at Site will be issued with Security passes by the Contractor to permit access to and from the Site. It shall be the Contractor's senior representatives responsibility to ensure that security rules are complied with. No vehicles will be allowed on site except those carrying materials, or necessary for construction.

The Contractor shall ensure that at least one person amongst the Site staff during Site working hours is trained in first aid and a first aid facility shall be maintained with basic needs.

The Contractor shall supply, maintain and service for the duration of the Contract, site office accommodation for the Owner/Engineer’s construction management personnel. This accommodation shall be separate from but adjacent to the Contractor’s own offices and other facilities. It shall comprise of a number of offices and include toilet and kitchen facilities. The offices shall be suitably furnished with desks, chairs, benches and lockable filing cabinets. The offices shall be installed with full office facilities, such as lighting and small power, telephone lines, water supply and drainage. The Contractor shall supply graded parking areas for Owner/Engineer’s vehicles.

Canteen facilities shall be provided by the Contractor during the construction phase.

On commencement on site the Contractor shall insure the Owner’s/Engineer’s offices and contents against fire, and other risks ordinarily insured against.

Before the erection of any temporary huts, sheds or other buildings which the Contractor may require for his own purposes, the Contractor shall obtain approval from the Owner/Engineer for the size, type, location and drainage arrangements. Notice shall also be given to the Owner/Engineer of any intention to dismantle any hut or remove the same from site.

After completion of erection of the office(s) and other temporary accommodation, the Contractor shall arrange an inspection, to be attended by the Owner/Engineer and the Local Fire Authority. The Contractor shall comply with all recommendations made by Local Fire Authority. Any costs involved in making the buildings comply with the Fire Officer’s requirements shall be deemed to be included in the Contract Price.

- 5.3 -


The Contractor shall provide sanitary conveniences for the use of workmen employed on the Works and in such a manner and number as shall conform to the statutory or other appropriate regulations and the whole shall be installed to the satisfaction of the Owner/Engineer.

The conveniences shall be located centrally to the Works and shall be to a high industrial standard, heated/ventilated (as necessary) and maintained in clean, hygienic and in good working order at all times.

The Contractor shall include for removal of all temporary offices, welfare facilities, sheds and other temporary buildings at the completion of the Works and restore the site to a state, to the satisfaction of the Owner/Engineer.

5.3 Site services during construction period

The Contractor shall be responsible for the provision of all site temporary or construction services. Refer also to the Civil Works section.

5.3.1 Site construction electricity supplies

The Contractor shall be responsible for making arrangements for the provision for the purposes of the construction of the Works of supplies of electricity, as may be required, including the provision at his own cost of any apparatus necessary for such use and the payment of any charges levied for such supplies should these be available from the Owner.

The Owner cannot guarantee the availability and/or reliability of any supply identified as existing at the Site.

All cables installed for temporary electrical supplies shall be routed so that they are clear of building operations or constructional work, shall not impede access and egress, and shall be at least 150mm clear of steam, gas and water pipelines. Lampholders and other accessories shall not be suspended from electric cables.

Cables passing under roadways and access ways for transport and mobile plant shall be laid in ducts at a depth of 600 mm. A cable marker shall be installed at each end of the road crossing.

Records and drawings of the temporary distribution system and cable routes shall be kept up to date.

As soon as any parts or whole of the Contractors installation is no longer required for carrying out the Contract Works, the Contractor shall disconnect and remove the same to the satisfaction of the Owner/Engineer.

5.3.2 Water supplies

The Contractor shall be responsible for making his own arrangements for any water supplies required during the construction of the plant, including any metering apparatus and the payment of any charges.

- 5.4 -


5.3.3 Other services

The Contractor shall also provide at least the following and others if required:

a. at laydown areas and at work faces temporary fencing, lighting and guarding and all other materials and services necessary for the safety and security of persons and property;

b. temporary roads, parking areas etc;

c. telephones

d. fire-fighting equipment;

e. waste disposal facilities;

f. sanitary facilities;

g. all necessary temporary equipment for construction, commissioning and testing; until project completion has occurred.

The Contractor shall include for the removal and disposal off-site of all ground works associated with the temporary services, including the removal of temporary sewage works, the safe demolition and infill of manholes, chambers etc, and the safe termination and/or blanking off from permanent services under the control of the Owner and/or other public or private bodies, to the satisfaction of the Owner/Engineer.

5.4 Health and safety at work

The Owner/Engineer will monitor the Health and Safety practices of the Contractor against the agreed H&S Plan which shall be prepared and developed by the Contractor and be subsequently approved by the Owner/Engineer.

On award of contract, but before construction work begins, the plan shall be prepared and passed to the Owner/Engineer for comment/approval and the Contractor shall ensure that it is regularly and properly adjusted to accord with the contractors involved and to site activities. The Contractor must incorporate into this plan comprehensive method statements for all major construction activities and provide copies of these to the Owner/Engineer. The method statements will include, but not be limited to, working methods, plant utilization, construction sequence and safety arrangements.

The Owner/Engineer will authorize construction activities to start only when advised by the Contractor that there is a sufficiently detailed execution stage of health and safety plan in place.

The Contractor shall make allowance within his programme for carrying out his duties in the above respects.

The Contractor shall prepare comprehensive method statements for all interface construction activities and submit these to the Owner/Engineer for review at least thirty (30) days prior to the commencement of the relevant activity. The method statements will include, but not be limited

- 5.5 -


to, working methods, plant utilization, construction sequence and safety arrangements, permit requirements etc.

5.4.1 Risk assessment

It will be the responsibility of the Contractor to provide both their generic and site specific risk assessments related to undertaking any hazardous work and/or use of any hazardous materials, and major HAZID and HAZOP studies as required to demonstrate the safety of the proposed design and operation of the plant, or as required under statutory legislation.

The Contractor shall ensure that risk assessments on the design elements of the plant are carried out, and the relevant information is included in the construction phase Health and Safety Plan.

5.4.2 Specific risks produced by contractor activities

The detailed Health and Safety Plan to be developed by the Contractor shall include method statements for all high-risk activities to be engaged upon by the Contractor and Sub-contractors. Work will not be allowed to start on site until method statements have been submitted and accepted by the Owner/Engineer.

High risk activities that have been identified for the construction works include, but are not limited to:-

a. Work on fuel gas and gas oil systems

b. Chemical handling

c. Working on and adjacent to water

d. Diving operations/working under water

e. Steel fabrication and erection

f. Scaffolding

g. Heavy crane lifts

h. Working at height

i. Hot work

j. Large plant handling and installation

k. Noise

l. Working with HV, MV and LV systems

m. Excavations

n. Construction of foundations

- 5.6 -


o. Contamination

p. Working in confined spaces

q. Working adjacent to highways

r. Tunnelling operations

s. Tie-ins to existing systems

t. Working adjacent to overhead cables/power lines

u. Radiographic testing of welds

v. Operation of plant.

On-site works must be fully co-ordinated by the Contractor. The Contractor should make due allowance for regular co-ordination meetings between all sub-contractors actively working or about to start working on the site. The Contractor, Owner, Engineer and representatives of the Owner will attend the meetings.

5.4.3 Documents

The Contractor shall provide the following documents:

a. The Statement of Safety Policy and Organization with Charts and Appendices.

b. The Health and Safety at Work Manual.

c. The Statement of Local Arrangements for Health and Safety, including:-

i. any Safe System of Working,

ii. any Permit to Enter system, and

iii. any Permit to Work System.

5.4.4 Contractor's safe systems of working

Prior to commissioning on Site, the Contractor shall establish a Safety and Permit-to-Work system for the Site to ensure that plant is put into and taken out of service in a safe and controlled manner, that the integrity of any adjacent operational plant is maintained and any adjacent construction work can be undertaken in a safe manner. The system shall incorporate where applicable any Permit-to-Work system employed by the Owner.

Where any part of the Works is not covered by the Contractor's Safety Policy or is a High Risk activity (as described below) the Contractor shall submit to the Owner/Engineer a method statement covering such part of the Works. He shall immediately submit to the Owner/Engineer any subsequent additions to or amendments of his method statement. No work covered by any method statement shall be commenced unless the Owner/Engineer has approved the method statement.

- 5.7 -


High risk activities include the following:

a. Steel erection/heavy crane lifts

b. Hot work

c. Entry into confined spaces

d. Use of explosives

e. Roof work

f. Excavation work

g. Degassing vessels/systems

The Contractor's Safe Systems of Working as described in his method statements shall:

h. be not inferior to the Owner's Safe Systems of Working for any part of the Site where both will apply;

i. incorporate where applicable any Permit to Enter or Permit to Work system employed by the Owner;

j. incorporate where applicable any of the documents listed above or any leaflet or card associated with them;

For the purposes of this Clause, references to the Owner or his employees shall be deemed to be references to any other party present or likely to be present on the Site at the same time as the Contractor.

5.4.5 Training

The Contractor shall provide or arrange appropriate training for his employees or any other persons carrying out, or put at risk by, his operations. Such training shall include written instructions incorporating the relevant portions of the Contractor's Safe Systems of Working.

Where training is required relating to the Owner's operations, the Owner will if so requested provide such training. In this event, the Owner shall have the right to be paid by the Contractor or the party given training the reasonable cost thereof.

5.4.6 Safety equipment

The Contractor shall provide all safety equipment for use on the Works; particularly for above ground and confined space working. Where such equipment is subject to statutory inspections, the Owner shall be provided with copies of the inspection reports.

When there is a risk of drowning the Contractor shall provide lifebelts and ensure that personnel wear adequate buoyancy equipment or harness and safety lines, and ensure that rescue personnel are present when work is proceeding.

- 5.8 -


5.4.7 Assistance to Owner

When the Contractor is required under the Contract to provide manual assistance to the Owner or his staff, the Contractor shall ensure that the person or persons so provided are aware of the dangers or hazards which may be encountered on the Site.

5.4.8 Confined spaces

Where any part of the Works is to be carried out in a confined space the Contractor shall:-

a. Display at the entrance to each confined space a sign warning of the need for oxygen and gas levels to be monitored before access and while work is proceeding.

b. Provide every person entering the confined space with appropriate training in the use of atmosphere testing equipment, the use of respiratory protective equipment, elementary first-aid and rescue techniques.

c. Monitor the atmosphere in the confined space for oxygen depletion and dangerous gases before any person enters it.

d. Provide every person entering the confined space with breathing apparatus, which shall be suitable for use while working or for emergency use only, depending on the degree of ventilation.

e. If sufficient means of natural ventilation cannot be guaranteed to provide at all times an adequate circulation of uncontaminated air, provide forced air ventilation even if regular/routine oxygen or other gas levels are shown to be safe.

f. Ensure that all persons within the confined space vacate it as soon as any alarm sounds, without waiting to record the gas level.

g. Provide appropriate harness, safety ropes and rescue facilities and if practicable two means of access top to bottom.

h. Provide when work is in progress radio or telephone communication, or safe visual and oral communication where this is appropriate and background noise levels permit.

i. Ensure that all electrical tools and equipment are of the appropriate types.

When access to a confined space is expected to be prolonged, for example during the construction of a tunnel, the Contractor shall augment the above procedures by installing continuously reading and recording oxygen and gas monitors within the entrance to the confined space and at the place of working. Such monitors shall operate for 24 hours per day, seven days per week, for the whole period of access to the confined space. The Contractor shall provide copies of the recordings to the Owner/Engineer at weekly intervals.

The Contractor shall include for training of the Owner/Engineer’s resident staff in confined space techniques.

- 5.9 -


5.4.9 Land owned by third parties

The Contractor shall take care when working on land owned by third parties to safeguard the Owners or occupiers of such land.

5.4.10 Temporary electricity supply

Where the Contractor obtains any temporary electricity supply from a switchboard or other source in the Owner's control, he shall submit to the Owner a copy of a certificate of testing and compliance with IEC 60364 before connection to the Owner's source is made, and again at the intervals for re-testing required by the Standard. If at any time the Owner does not hold a current certificate the Owner will disconnect the Contractor's supply.

5.4.11 Fire precautions

The Contractor shall take all necessary precaution to prevent fire. Where new risks are introduced in the Works during the construction period, the Contractor shall provide appliances suitable for such risks.

When working in potentially explosive atmospheres the Contractor shall employ approved non-electric tools and apparatus suitable for use in such areas.

5.4.12 Compressed gases

The Contractor shall make adequate arrangements for the safe storage (including appropriate warning notices) and handling of all compressed industrial gases.

5.4.13 Access, fencing and safety barriers

The Contractor shall give notice to the Owner's operating staff whenever he proposes to start any work which may impede the safe passage of persons and vehicles in an emergency.

The Contractor shall provide appropriate safety barriers with hazard warning signs attached around all exposed openings and excavations when the work is in progress. Permanent or approved temporary covers to openings shall be replaced at all other times.

5.4.14 Site rules

5.4.14.1 Statutory and other regulations

The Contractor shall comply with all Iraq National Acts and Statutory or other regulations.

If the law is broken or regulations disregarded, the Owner may exercise his right to refuse to allow the offenders to remain on Site and will not be responsible for any cost penalty arising therefrom.

In the event of the Contractor employing subcontractors, it must be clearly understood that it is the responsibility of the Contractor to ensure that the subcontractors understand and comply with all regulations in every respect.

- 5.10 -


5.4.14.2 Safety helmets and safety footwear

The Contractor shall provide all safety equipment for use on the Project and ensure adequate training in the use thereof. The safety equipment provided shall be in accordance with internationally recognized standards for this location. Where such equipment is subject to Statutory Inspections, the Owner shall be provided with copies of the inspection reports.

Personal protective clothing which will provide adequate protection for workers such as high visibility jackets, safety helmets, safety footwear shall be worn at all times and shall be provided by the Contractor. Adequate arrangements shall be made for regular cleaning of the protective clothing.

Non-slip or studded boots should always be worn because of the risk of slipping on greasy surfaces. All studs should be non-sparking.

5.4.14.3 Protection of hearing

Where sound levels cannot be reduced at source, the provision of suitable hearing protection is required when noise levels indicate an equivalent level (Leq) of more than 85 dB(A). When hearing protection is used arrangements should be made to ensure the wearers can be warned of other hazards.

5.4.14.4 Eye protection

The following are engineering jobs which always require eye protection by persons doing or closely observing the work:

a. The grinding of metal, stone, concrete or similar materials by a mechanically powered wheel or disc.

b. Breaking, cutting, dressing or carving of stone, concrete, slag or similar materials by a powered or non-powered tool.

c. Chipping or scaling of painted or corroded metal surfaces or wire brushing of such surfaces by mechanical power.

d. Cutting out or cutting off of cold rivets or bolts.

e. Welding

5.4.14.5 Respiratory protective equipment

Where there is a risk to persons at work from a dangerous atmosphere, appropriate breathing apparatus must always be readily available for use and all persons concerned must have received adequate training in the working principles and use of this equipment.

Breathing apparatus may need to be used in both routine operations and emergency situations. It is important that the correct equipment is selected for the particular environment for which the user requires protection and that approved procedures are followed in the general care, use and maintenance of such equipment.

- 5.11 -


5.4.15 First aid and medical facilities

The Contractor shall be responsible for the provision of first aid facilities at Site, for the use of his own workforce and that of his subcontractors. The Contractor shall also be responsible for the contingency planning for emergency services in the event of incidents, accidents or other emergencies at Site.

Medical facilities will not be provided by the Owner and the Contractor shall be required to make his own arrangements for these services as may be required for his expatriate or locally engaged staff.

5.4.16 Emergency evacuation of the Site

The Contractor will establish a Procedure for the evacuation of the Site in the event of fire, bomb warning or other emergencies. The Contractor shall provide any adequate checking system to ensure that all his employees are removed from the Site in the event of such emergencies. The Procedure will include arrangements for practice evacuation as necessary and shall be agreed with the Engineer.

5.4.17 Safety management

The Contractor shall formally appoint a suitably qualified member of his staff to be responsible for safety aspects of the work on Site and shall ensure compliance with all safety matters of the appropriate local legislation.

5.4.18 Cranes, hoists, lifting equipment and scaffolds, etc

All lifting appliances (cranes, pulley blocks, gin wheels, etc) hoists and lifting gear (chain slings, rope slings, etc) must be tested and inspected in strict conformity with the requirements of Schedule G. Records and certificates must be available for inspection at any time.

The Contractor is responsible to see that hired cranes comply with the regulations and current certificates are available for inspection.

All overhead scaffolds and suspended loads must be properly secured. Approach ladders must be removed or made unscalable whenever the Site is left unattended. Scaffold boards and/or cat ladders must be used when working on roofs. Aluminium alloy scaffolding may not be used. Kick plates shall be provided on all scaffold boards

5.4.19 Electrical safety conditions

All work on the site shall be carried out in compliance with the relevant Iraq National and local Construction Regulations.

5.4.19.1 Portable and transportable equipment

All portable hand-tools and equipment should operate on 50 volt ac supply unless specified otherwise.

- 5.12 -


Under certain circumstances, tools and equipment for use on 110 volt ac supply may be used, but only if written permission is given by the Owner, who will first ensure that the earthing arrangements are satisfactory.

If only 240 volt ac or 400 volt ac equipment is available special dispensation must be obtained, in writing, from the Owner/Engineer. Dispensation will only be given if a monitored earth leakage unit is fitted.

Portable lighting shall operate at not more than 110 volt ac single-phase.

All electrical equipment must be in safe working condition to the satisfaction of the Owner/Engineer. Should equipment be found to be faulty it must be made good by the Contractor at his own expense or otherwise replaced.

5.4.19.2 Supplies

The Contractor shall be responsible for obtaining any electrical supplies required to carry out his contract works including all that is necessary to provide a safe and satisfactory supply and distribution system.

5.4.19.3 Contractor's wiring

The Contractor's distribution, lighting systems and hut wiring shall be in accordance with Internationally acceptable standards for the distribution of electricity on construction and building sites.

5.4.19.4 Lighting

It is the responsibility of Contractor to provide adequate lighting in every work place. The lighting system shall be such that nuisance to local residents shall not be caused.

- 6.1 -


6. MECHANICAL PLANT AND SYSTEMS

This part of Technical Specification covers the mechanical plant and systems, including two gas turbine units, complete with their compressors, combustion chambers, auxiliary gears, starting system, shutdown system, lubricating system, inlet air and exhaust systems etc, together with all other mechanical systems and equipment common to both gas turbine units such as fuel and water supply, fire fighting, cooling and compressed air systems, piping, valves, heating, ventilation and air conditioning systems, mechanical workshop equipment, cranes, hoists etc.

The overall scope of supply is broadly indicated in Section 3 and is specified in detail in the following mechanical subsections and associated Schedules. All other accessories required for the safe and continuous operation of the plant, even if not specifically mentioned in the Specification, shall be considered to be included.

6.1 Gas turbines

6.1.1 General

Gas turbines shall be single shaft heavy industrial type units, operating in simple (open) cycle, capable of operating continuously at base load as defined in Section 2, over the range of ambient conditions and on the fuels as defined in Schedule A. The combustion system shall be selected by the Contractor to provide efficient and reliable service throughout the range of operating conditions and environmental requirements as defined in Section 2. Reliability, prompt starting, ease of operation and a minimum of maintenance attention are primary considerations, and the rating and frame size chosen by the Contractor shall reflect this.

The gas turbine plant shall be complete with all accessories and station common auxiliaries as specified herein; redundancy in the gas turbine auxiliaries shall be clearly indicated in the schedules.

The gas turbine components shall be designed for long life, reliability and to maximize the hours between repair or replacement. A complete list of components to be changed/repaired during planned outages shall be provided, including but not limited to hot gas parts such as combustion nozzles, combustion chambers, transition pipes, inlet nozzles and blades.

The gas turbine compressor unit shall be of single shaft, proven manufacturer standard, which can be demonstrated to have been in reliable operation for a number of years. For the gas turbine offered, the Tenderer shall provide information on the development and operational history. Developments and modified components introduced to the gas turbine model, including the affect on performance and reliability shall be fully described together with chronological dates and the operating hours achieved since new developments were introduced.

Each gas turbine and all ancillary equipment shall be enclosed in a weather protection acoustic enclosure designed to suit the environmental conditions stated for the site, and shall be arranged to facilitate easy handling during inspection and maintenance activities.

The Contractor shall avoid offering sophisticated and complicated equipment where simple and proven equipment will achieve the specified requirement.

- 6.2 -


6.1.2 Turbine

The turbine shall be of multistage design; the blading shall be designed to avoid the possibility of damage by vibration and to minimize the effect of any rubbing against the casing. The rotor design shall allow interchange of blading at site without need to rebalance the rotor.

Blade and nozzle materials and coatings shall have proven capability when operating at the base load and peak load gas temperatures. Where component designs have been modified and where proven satisfactory operation to the relevant planned outage cannot be substantiated, an extended warranty shall be provided for those components.

The Contractor shall consider the need for and if necessary provide offline turbine wash facilities. Such facilities if offered shall be of a proven design and the Contractor shall fully substantiate the need for this equipment by providing comparative details of expected blade fouling and performance degradation with and without offline washing facilities.

6.1.3 Compressor

The axial flow compressor shall be robust and have sufficient surge margin to remain stable and surge–free over the whole range of operating conditions likely to be experienced on site.

Bleed valves and variable geometry guide vanes shall be a feature of the design to permit more efficient part load operation and to avoid compressor surging or any other undesirable flow conditions at low compressor speeds.

The compressor stator and rotor blading shall be suitably treated by coatings or be of a suitable material to resist erosion and corrosion.

6.1.4 Casings

The design of the casings shall be such as to permit examination of the rotor blading without disturbing shaft alignment or causing damage to blading. Boroscope ports are to be provided to permit examination of components in the hot gas path without disturbing the casing. The number and position of ports, and the hot gas components which can be observed through them shall be defined in the Tender. A boroscope and camera shall be included in the scope of supply.

The methods proposed for avoiding gas leakage at any joints on the turbine and for avoiding cracking in the turbine ducting due to thermal cycling shall be described.

Where it is required to use bolt heating apparatus and/or torque spanners to exert a pre-determined torque to tighten casing flange bolts, such apparatus shall be provided as part of the Contract including any other equipment needed such as transformer, cabling to extensometer, etc.

The entire gas turbine casing shall be heat insulated in such a manner as to allow easy removal and replacement for overhaul and inspection. The insulation material shall consist of non-combustible and chemically inert material, and shall be designed to avoid any soaking with fuel oil or with lubricating oil.

- 6.3 -


6.1.5 Turbine and compressor rotors

The turbine rotors shall be designed to withstand all stresses resulting from a turbo-generator short-circuit without taking any permanent set or strain, and shall be designed to safely withstand 120 per cent of rated speed.

There shall be no critical speed within the range of 20 per cent above or 20 per cent below the normal running speed of any shaft. The Contractor shall state the minimum factor of safety (based on 1 per cent proof stress) existing in the rotor disc or discs.

Each bladed rotor shall be statically and dynamically balanced and overspeed tested at the manufacturer’s works. The remaining unbalance shall be in accordance with equivalent code and standard subject to the Owner/Engineer’s approval. Relevant test records and certificates shall be provided by the Contractor.

Approved vibration measuring devices shall be provided at each turbine and generator bearing as defined in Section 8 of this Specification. Under steady state conditions when running at normal operating speed, vibration amplitudes shall not exceed those specified in ISO Standard 10816 Part 4 and ISO 7919 Part 4, as applicable.

The construction of the rotor, the heat treatment proposed and the procedures for inspecting the shaft and ensuring soundness and thermal stability shall be described in the Tender.

6.1.6 Blading

The blading shall be designed to withstand all vibration, thermal shock, gas and mechanical loads that may be experienced during service. Materials employed shall be consistent with proven standards for long term operation, using the fuels specified, in the environmental conditions existing at the site. Where a proven coating to improve corrosion and erosion resistance is available, this shall be provided and a technical description given. Each rotating blade shall be weighed and numbered in such a way that the number will still be legible at the end of the blades useful life. The record of each of the blade weights shall be handed to the Owner at the Taking Over date.

The design and fixing of turbine blading shall be such that any stage or portion of a stage may be removed and replaced at site.

All rotor and stator blading shall be designed to avoid resonant frequencies with the materials used. The fundamental frequencies of all blading shall be at least 10 per cent away from the passing frequencies of any stationary parts.

Where variable geometry blading is proposed the Contractor shall state his method of ensuring that the blading cannot seize in a dangerous position.

6.1.7 Burners and combustion system

The type of combustion system offered shall take into consideration the fuels specified herein for all operational modes. Technical details of the combustion system shall be provided in the Tender, together with references/experience of operation with the specified fuels.

- 6.4 -


The turbine combustion system shall be designed to operate reliably for the operating periods between inspections and outages. The combustion system shall be capable of achieving the specified emission levels over all specified operational and transient conditions without compromising the robustness and durability of the system.

Reliable flame monitoring equipment shall be provided and signals sent to the CCR.

Combustion chambers shall be constructed from suitable materials in such a way that the nozzle cleaning and flame tube examination can be carried out without disturbing the rest of the unit. Suitable means shall be provided to purge the gas path in the event of a flame failure.

6.1.8 Couplings

The coupling type and details are to be stated. The coupling bolts, keys, etc, shall be capable of withstanding the maximum generator short circuit torque and the maximum torque due to inaccuracies in synchronization without exceeding permissible stress levels.

The coupling between accessory gear and gas turbine shaft, shall be an oil lubricated gear type coupling or approved equivalent. It shall have lubrication such that it is capable of operating at full accessory load for 10,000 hours between service inspections.

All necessary coupling guards shall be provided for protection of operating personnel.

6.1.9 Compressor cleaning

Permanent compressor cleaning and washing equipment shall be provided based on an inhibited wet wash system designed for both on-load and off-load washing. All equipment necessary for the storage and handling of the cleaning agent shall be included and the first filling of the system and requirements to the end of the guarantee period shall be provided under the Contract.

The wash system shall include a wash water skid including detergent/inhibitor tank, bulk heaters (if necessary), metering and pressurizing pumps, piping, strainers and valves all manufactured in a suitable grade of stainless steel. The system shall be designed for steady, evenly distribution of cleaning fluid and shall ensure that cleaning fluid, water or debris does not enter instrument, atomizing air and other system pipework.

The wash water system shall be designed to operate automatically and shall be capable of operation both from a local panel and from the CCR.

Full details of the automatic cleaning sequence for off-line water washing of the unit shall be provided with the Tender. The total time elapsed for completion of this operation commencing from and returning to full load operation of the gas turbine shall be clearly stated.

Liquid discharges from the cleaning process shall be discharged to suitable on-site storage for eventual off-site disposal. The water wash liquid discharge collection tank shall be common to both gas turbine units and shall, as a minimum, have sufficient capacity to contain 110 per cent of the full volume of water required to carry out three water washes on a gas turbine unit.

- 6.5 -


6.1.10 Starting equipment

A starting unit shall be provided to accelerate the gas turbine generator up to self sustaining speed. It shall be suitable for extended operation at purge, warm-up, accelerated cool down and compressor cleaning speeds.

The starting system shall include automatic control features and such additional equipment as is necessary to ensure reliable starting capability in the shortest possible time.

The preferred system is to use the generator as a motor via a suitable static frequency converter (SFC) system, however a manufacturer’s proven standard may be accepted.

If starting systems of the SFC type are offered, one SFC shall be provided for each gas turbine, and the turbine barring gear shall be designed to bring the turbine up to barring speed from rest independently from the SFC system.

The starting sequence shall incorporate a period for purging the gas path of any dangerous fuel/air mixture and drain the system of any un-ignited fuel. Protection shall be built into the sequence so that in the event of an abortive start another start cannot be attempted until conditions are safe to do so.

The maximum time needed to bring the unit from rest to self sustaining speed shall be stated in the Tender.

Refer to Section 7 for further details of the requirements for starting equipment.

6.1.11 Rotor barring

Means shall be provided for powered barring of the machine rotor for sufficient period following normal or emergency shutdown to ensure satisfactory cooling of components. Where SFCs are supplied these shall not be the only means of powered barring.

Barring shall be initiated automatically as part of the turbine run down sequence. When conditions are suitable for barring to cease, this information shall be automatically indicated in the local and remote positions.

The lubrication system shall be compatible with long term barring without damage to bearings.

As a back up to the powered barring systems, means shall be provided for barring of rotors by hand for emergency use.

A push button initiated barring facility shall be provided in the turbine compartment with facility to allow the rotor to be inched from the combustion area during inspection.

6.1.12 Auxiliary gear

If an auxiliary reduction gearbox is required for turbine driven auxiliaries it shall be of a proven design for this type of application. It shall be capable of transmitting the maximum rating of

- 6.6 -


the auxiliaries with a minimum service factor of 1.2 per AGMA standards. All bearings shall be readily renewable and it shall be possible to inspect the bearings and gear teeth without disturbing the shaft alignment.

The design shall be such that under operating conditions the gearbox shall be quiet and vibration free.

6.1.13 Gas turbine generator lubrication system

6.1.13.1 Bearings

All journal bearings of the turbine generator unit shall preferably be of the babbit lined, pressure oil lubricated and cooled, split, and self-aligning type. Segment-type journal bearings causing lower friction losses may be offered if the Contractor can prove ample experience with such bearings.

The design should allow the bearings to be examined and/or replaced without dismantling the casings, and with the minimum shaft lifting. Appropriate lifting equipment shall be provided for this operation. Bearing housings shall be designed to prevent any oil leakage into the gas stream.

Each journal bearing shall be equipped with RTDs or duplicate thermocouples (dual element thermocouples are not permitted). A sight flow indicator to check the oil flow leaving the bearing and a thermometer each for local and remote measuring of the oil temperature shall be provided at the bearing outlet.

Bearing pedestals shall be equipped with bearing vibration pick-ups to measure the horizontal and vertical component of vibration; details of the vibration monitoring system are defined in Section 8.

The axial thrust bearing shall be lubricated and cooled with oil under pressure and shall be of the self-aligning type or other reliable design to the manufacturer’s standard. It shall be equipped with thermocouples to measure the bearing metal temperature. Means shall be provided to monitor and to annunciate the wear and tear of the thrust pads during normal operation, with alarms to give warning of excessive wear.

6.1.13.2 Lubrication system

Separate lubricating oil systems shall be provided for each gas turbine generator unit. Each system shall be complete and of ample capacity and rating to supply oil at a suitable pressure as applicable to the gas turbine, shaft driven auxiliary equipment, gearing, generator, continuously lubricated couplings, governing and hydraulic systems.

The lubricating oil system shall cater for loss of the main lubricating oil pump whilst on load, momentary loss of ac power whilst on load, and safe shut down following loss of ac power.

A description of the system, together with a diagram of the proposed lubricating system shall be provided in the Tender. For the hottest ambient conditions to be encountered at the site, the oil outlet temperature at any bearing shall be less than the maximum safe operational temperature of the lubricant with an adequate deterioration margin.

- 6.7 -


The lubricating oil system shall, as a minimum include the following:

a. Lubricating oil tank

The lubricating oil tank shall be complete with oil level instruments to initiate alarms for high and low tank level, and thermostatically controlled immersion heaters (if necessary).

The tank vents comprising duplicate extractor fans and oil mist coalescers or electrostatic precipitators shall be routed to a suitable point, so as to prevent entrainment in the combustion air intake.

The tank shall include necessary hoses and couplings for connection of a mobile oil purifier, and for filling and emptying the tank.

Bunding shall be provided for the oil tank, sized for 110 per cent of the stored oil volume.

b. Lubricating oil pumps

The tank mounted pumps shall include :

One shaft driven main lubricating oil pump, driven from the accessory gear, complete with panel mounted pressure gauge and pressure relief valve.

One 100 per cent duty ac starting and standby pump, arranged to start automatically if lubricating oil pressure falls to a pre-set figure.

One reduced capacity dc motor driven emergency oil pump (for safe shutdown) with line-mounted pressure gauges. The dc pump shall be mounted separately on the lubricating oil tank; mounting on the ac lubricating oil pump is not acceptable.

c. Lubricating oil cooling

Cooling of lubricating oil shall be either by direct air cooling, or by cooling with closed circuit cooling water. For direct cooling, the oil shall be circulated through a fin/fan cooler. For water cooling, two full capacity (2 × 100 per cent) lubricating oil/CCW coolers shall be provided, connected to the turbine closed circuit cooling water system. Coolers shall be provided with facility for on-line change over from one cooler to another without loss of system functionality.

An automatic thermostatically controlled valve shall be provided to maintain oil temperature at the required operating value, together with a dial thermometer at the outlet of each cooler, fitted with an adjustable alarm contact to initiate a high temperature alarm.

The exchanger type and materials of construction shall be stated in the Tender. For further details of cooling system, refer to Section 6.4.

- 6.8 -


d. Lubricating oil filters

Duplex type full flow lubricating oil filters of the replaceable cartridge type complete with inlet and outlet pressure gauges and differential pressure indication and alarm equipment to monitor the filter pressure drop, and facility for on-line change over from one cooler to another without loss of system functionality.

e. Lubricating oil piping and instruments

All piping, equipment and component parts in contact with lubricating oil shall be steel; suitable grade stainless steel piping shall be utilized for the oil supply to the bearings.

The oil and water pressures shall be selected to avoid leakage of water into the oil system.

Lubricating oil pump discharge header instruments consisting of thermocouples, high temperature alarm and trip switches, low pressure alarm and trip switches, and a panel mounted pressure gauge shall be provided, together with flow and temperature indication from every bearing and measurement of all journal bearing metal temperatures.

f. Lubricating oil accessories

One portable electrically driven sump pump shall be provided (one pump for two gas turbine units), capable of emptying the lubricating oil system to a tanker or barrels within four hours.

Mobile oil purifier (common for two gas turbine units): centrifugal type oil purifier, complete with circulating pumps and valves for flow adjustment, and inlet heater. The purifier shall be capable of both on line and off line operation, shall be and rated for at least 5 per cent of the total oil system volume per hour.

g. Oil flushing and first fill

High importance shall be given to the cleanliness of the lubricating oil system during factory assembly and site construction. The on base sections of the lubricating oil system shall be flushed and sealed in the factory before delivery to site. The Contractor shall provide oil, which shall be of the inhibited type for transporting the set. Thereafter the contractor shall provide all oil until the take-over of the plant. The Contractor shall ensure that the oil system is thoroughly clean before introducing the first charge of oil.

h. Jacking oil system

Jacking oil shall be provided, if necessary, to minimize starting torque and for use during barring. Full redundancy of the jacking oil system shall be incorporated. Means to bar the unit in the event of a station blackout and loss of normal ac

- 6.9 -


power shall also be provided. A facility to allow hand barring in the event of a barring gear motor drive failure shall be provided.

i. Hydraulic oil system

The hydraulic oil for the gas turbine shall be the same as the lubricating oil, supplied from the same reservoir.

A duplex filter for the hydraulic oil shall be used which allows on-line changeover at full load without loss of system functionality. Both a main and auxiliary hydraulic oil pump shall be supplied.

6.1.14 Combustion air inlet system

6.1.14.1 General

The gas turbine air intake air system shall comprise self-cleaning type air filtration equipment, dust removal system, ducting, guide vanes, silencers, internal lighting and all necessary controls and instruments for the safe and efficient operation of the system.

The Contractor shall be responsible for ensuring the most appropriate design and selection of air intake system, based on the ambient conditions, noise criteria and air quality prevailing at site and shall carry out any studies, including air sampling on site as necessary to ensure that the design is optimized, considering the requirements for minimum maintenance and maximum filter life.

In order to protect the filter media, the intake system shall include weather hoods/rain louvres and droplet eliminators upstream of the filter cartridge, and shall include appropriate features (eg anti-icing, air drying system) for the protection of the unit throughout the complete range of operating conditions, and during shutdown of the plant.

The filter element media shall be of a heavy duty type in order to minimize frequency of replacement and pulse cleaning. The filter elements shall have a guaranteed operational life of [18,000] operating hours (minimum) under the specified site conditions. The Tenderer shall provide details of field operating experience of the proposed filtration system under similar conditions as expected for this Site.

Each self cleaning filter unit shall have its own dedicated compressed air system for pulse cleaning purposes. The compressed air system shall generally comprise of an air compressor, receiver, valves, piping, instrumentation, and controls, and shall be sized to ensure reliable and trouble free operation of the pulse filter system. The air for pulsation shall be clean dry air at a pressure as required by the system. Air from the plant compressed air system shall be used only as a backup source.

Differential pressure measurement across the filter stage, linked through the PCS shall be provided for alarm and initiation of the cleaning cycle.

Permanent access and service areas shall be provided, including access hatches viewing windows and appropriately positioned walkways in the inlet duct downstream of the air filter to allow inspection and maintenance. Lifting facilities to enable efficient removal and installation of filter

- 6.10 -


elements and adequate lighting shall also be provided to support all maintenance and inspection activities, and any special tools required for maintenance or cleaning of the filter shall be supplied.

Full details of the equipment being offered shall be provided in the Tender, including arrangement and layout drawings for the filters, all technical and performance data for the filters and pulse air system.

6.1.14.2 Air drying

An air drying system comprising an electric heater absorption wheel and air blower shall be provided to circulate dry air into the compressor intake plenum and through the complete gas turbine to prevent corrosion whilst the unit is shut down.

The dry air system should include its own air filter and a stop valve to isolate the system from the gas turbine. This stop valve must be proved closed before a gas turbine start can be initiated.

The system shall preclude any risk of moisture entering the system or being transferred by the circulating air.

6.1.14.3 Anti icing

Suitable provision shall be made to protect the air intake from the effects of icing. Details of the proposed system shall be provided in the Tender, together with references and operating experience in similar situations.

6.1.14.4 Dust removal system

An automatic system shall be supplied for the removal of dust from the air intake system during pulse cleaning sequence, in order to avoid re-entrainment of the dust particles in the surface of the filter elements. The dust removal system shall ensure that dust is contained and prepared for off-site disposal. Details of the proposed system shall be provided in the Tender, together with references and operating experience in similar environments.

6.1.14.5 Intake ducting and silencers

The materials and coatings used for the construction of the intake ductwork, filter frames, and silencer section shall be chosen for resistance to erosion and corrosion under the prevailing site conditions.

All intake ductwork shall be designed to withstand the negative internal pressure which may develop under the most adverse operating conditions. Stiffeners shall be on the outside of the ducting. Internal stiffeners are not acceptable.

Expansion joints shall be provided with internal plates to prevent turbulence or deposition of dust in the joints. Exposed joints shall be protected from solar radiation. The arrangement of duct work shall enable lifting of turbine parts i.e. casing, rotor, etc during maintenance without interference with these ducts.

- 6.11 -


Access doors shall be provided in the ductwork to give access to upstream and downstream faces of filters, silencers, and turning vanes and to permit examination of the gas turbine inlet flange and duct internals. Fittings on manholes and doors shall be designed to permit their use without risk of parts being ingested by the gas turbine. All doors provided on the filter house shall be fitted with proximity switches to alarm if the doors are not fully closed.

Pressure tapping points shall be provided in each section of the ductwork and sealed with screwed plugs.

A trash screen manufactured from 316L stainless steel shall be fitted downstream of the inlet silencers and adjacent to the machine intake.

Silencing equipment shall be provided for the air intake system as may be necessary to reduce the sound pressure to the levels as defined in this specification.

The attenuator panels shall be designed for the life of the plant operating at 100 per cent base load site rating and shall be fully resistant to effects of dust laden intake air. Precautions shall be taken to prevent settling or packing of acoustic fill material. Silencer panel materials shall be corrosion resistant and manufactured from high quality stainless steel.

6.1.15 Gas turbine exhaust

6.1.15.1 Exhaust ducting

The exhaust ducting shall be designed so that it does not vibrate during operation and shall be supported in such a way that loads on the turbine do not exceed those which the turbine can accept, and do not change significantly due to the thermal affects.

The material of the exhaust ductwork, guide vanes and expansion joints shall be selected to resist the temperature and corrosion effects of the gas and suitable for the base load flow and temperature conditions.

The ducting shall be internally insulated, with stainless steel cladding/liner secured by stainless steel studs welded to the duct wall. Sheet retention shall be by means of large stainless steel washers and stainless steel nuts. The external insulation shall be sufficient to ensure the outside casing temperature shall not exceed 60°C, and shall be clad with 1.2 mm thick marine grade aluminium sheeting.

Manholes or doors shall be provided in the ductwork to give access to turning vanes and to permit examination of duct internals.

Pressure tapping points shall be provided in each section of the ductwork and sealed with screwed plugs.

The exhaust duct support system shall be designed to allow for free expansion of the duct. Sliding supports shall not require any lubrication.

- 6.12 -


6.1.15.2 Expansion joint

The design of any expansion joints shall ensure that their replacement is not required prior to a gas turbine major overhaul.

Expansion bellows of the fabric type are preferred and shall be arranged that no shear loads are imposed upon them. The design shall be such that the temperature of any PTFE layer does not exceed 250°C and also that there are no parts of the bellows where products of combustion can cause deterioration. Particular care should be taken with the design, construction and erection of the bellows units to avoid high stresses or excessive bending and vibration of wires or fabric.

Guards shall be provided to prevent external damage to the bellows and at the same time allow free air circulation. The guard on top of the bellows shall be arranged so as to prevent deposition of materials onto the surface of the bellows.

Expansion joints shall be provided with internal plates to prevent turbulence or deposition of dust in the joints.

The bellows shall be designed so that it does not double back on its self, i.e. there shall be no high temperature folds in the bellows material.

The bellows shall be attached to outstand flanges so that external access to the fixing bolts is achieved. All fixing bolts and nuts shall be treated with an anti- corrosion compound.

6.1.15.3 Exhaust silencers

Sound absorbent material in the exhaust silencer baffles shall be non-hygroscopic, and resistant to attack by moulds, insects and resistant to the high temperature and corrosive effect of the exhaust gases.

The material shall be supported so that it does not shake down and remains in its correct position during the life of the plant, and shall be separated from the silencer baffles by stainless steel wire mesh to prevent entry of the packing material into the air/gas stream.

Silencer elements shall be manufactured from an approved grade of stainless steel.

6.1.15.4 Exhaust stack

The Contractor shall be responsible for suitable stack design of sufficient height, temperature and velocity to minimize environmental impact and comply with local regulations and guidelines, as defined in Section 2. The stack shall be configured to avoid exhaust gas being ingested into the air inlets of any adjacent machines, or into the inlets of any building, ventilation or air conditioning units in the vicinity, under any weather conditions at the site.

For the purposes of bidding, the minimum stack height shall be considered as [25] metres. The stack height shall be subject to review once studies have been carried out.

- 6.13 -


The stack shall be self-supporting or supported by adequate steel structure, and shall be designed to withstand all loads due to wind, vibration, etc, taking account of the thermal effects of the exhaust stack on the support structure and the influence of winds on adjacent stacks and buildings.

The exhaust stack material, insulation and internal/external protection shall be selected by the Contractor, taking into consideration the operating regime of the plant. The stack shall be insulated and clad where necessary for personnel protection.

Inspection doors or manholes shall be provided so that stack internals can be examined at vulnerable points eg support points, transition sections etc.

If required, the stack shall be equipped with an approved lightning protection system, in accordance with BS 6657 or equivalent, and shall include totally enclosed, vapour type aviation warning lights.

The stack shall be provided with external ladders (with safety rings), platform at the top of the stack and intermediate platforms spaced at 10 m (maximum) apart. The platforms shall give unrestricted access to stack manholes, aviation warning lights, emission monitoring equipment etc.

Fittings shall be included at the top of the stack for the attachment/support of maintenance and painting cradles. One set of all necessary maintenance equipment shall be supplied. The cradle movement equipment shall be motor operated.

Details of the proposed stack design, including material selection, insulation and protection for the stack and vortex-shedding device (if necessary) shall be submitted with the Tender.

6.1.15.5 Continuous emissions monitoring system (CEMS)

A continuous emissions monitoring system (CEMS) for monitoring of the oxides of nitrogen (NO BxB), carbon monoxide (CO), oxygen (OB2 B) and oxides of sulphur (SOBx B) shall be installed in the exhaust stacks. A permanent access platform shall be provided to allow maintenance of the sample points.

The equipment shall be of proven reliability and acceptable to local authorities. It shall be subject to the approval of the Owner/Engineer. The equipment shall have a proven record of use in similar CEMS applications. Details of other sites where the equipment has been installed shall be given. All equipment necessary for the installation, commissioning, calibration (including calibration gases), operation and maintenance of the monitoring equipment shall be supplied.

Further requirements of the CEMS are included in Section 8 of this Specification.

6.1.16 Gas turbine enclosure

6.1.16.1 General

Each gas turbine generator unit and auxiliary equipment shall be housed in an individual acoustic weatherproof enclosure to be supplied under the Contract.

- 6.14 -


The enclosure shall be designed to ensure the plant meets the noise requirements in Section 2.

The plant shall be arranged so that routine maintenance not requiring the removal of the turbine casing can be carried out in safety whilst the plant is in operation.

All doors shall be fitted with locks and they shall be of such a type that personnel cannot be trapped inside in the event of fire.

The local control room shall be partitioned from the gas turbine enclosure by a fire proof, gas tight barrier and shall be separately ventilated and air conditioned.

Refer to Section 6.5 for further details of the fire protection system for the gas turbine enclosures.

6.1.16.2 Turbine enclosure

The gas turbine and auxiliary equipment shall be housed in an acoustic weatherproof enclosure. The enclosure shall be provided with suitable fire protection/detection, gas detection, ventilation, lighting and maintenance facilities.

Provision must be made for the maintenance of the equipment so housed, and it shall be possible to remove parts of the enclosure if necessary, for overhaul purposes and re-assembly without destroying the acoustic and weatherproof sealing.

All instrumentation required to be monitored during normal operation shall be positioned such that it is easily accessible and readable external to the enclosure. Where this is not possible the instruments should be located in an illuminated position such that they can be read through suitable windows in the enclosure.

Lighting is to be provided in all enclosures such that maintenance work can be carried out without the use of additional torches etc. Internal enclosure lighting shall be capable of withstanding the environment within the enclosure without damage and shall be suitable for the hazardous area classification of the enclosure.

A dc emergency lighting system shall be provided in addition to the normal ac lighting.

Suitably placed power sockets for welding and power tool supply shall also be provided.

6.1.16.3 Gas detection

The gas turbine enclosures shall be provided with duplicate gas detection systems to monitor the escape of fuel gas. The detectors shall be capable of being maintained and calibrated without entering the enclosure. Alarms associated with the systems shall be raised local to the unit and at the Central Control Room.

Refer to Section 8 for further details.

- 6.15 -


6.1.16.4 Enclosure ventilation

The Contractor shall demonstrate that the enclosure ventilation system has been adequately modelled to ensure that no stagnant areas will exist within the enclosure where gas leakage could accumulate leading to a dangerous situation.

All enclosures compartments shall be extract or pressure ventilated. The ventilation system shall continuously change the air within the enclosure whilst the unit is running to ensure a satisfactory enclosure temperature. The system shall be provided with sufficient redundancy such that failure of a single component does not affect system operation.

The system must be able to cope with the worst conditions of temperature and humidity to be encountered at site.

Interlocks between the fire alarm system and the ventilation air inlets shall be provided such that the air inlets will close automatically on initiation of the fire protection system.

Ventilation air inlets shall incorporate weather hoods and filters to prevent ingress of rain, airborne dust and insects.

6.1.16.5 Air conditioning

The local control room and the generator auxiliary compartment shall be air conditioned, which shall be designed to maintain the air temperature therein to 25°C during periods of maximum ambient temperature considering four personnel in attendance.

A minimum of two air conditioners of the split type are required for each compartment.

Air conditioning units shall be suitable for operating from the standard ac supply and shall be fully accessible for maintenance.

All air conditioning unit drains are to be piped to external ground drains.

All air conditioned compartments are to be thermally insulated on all surfaces to avoid external condensation.

6.1.16.6 Maintenance facilities

Facilities such as support cradles, monorails, block and tackle, lifting beams or roll-off gear etc shall be provided in all enclosures to ensure that components can be transported for maintenance/repair without damage. The Contractor shall demonstrate in the Tender the maintenance of the major equipment including identifying transport, crane access and laydown areas.

- 6.16 -


6.2 Fuel systems

6.2.1 Fuel gas supply system

6.2.1.1 Gas supply

Fuel gas to the plant will be supplied from [ ].

Preliminary fuel gas supply conditions are provided in Schedule A for information.

The Contractor is responsible for obtaining sufficient data regarding the fuel supply conditions, including fuel analyses as necessary for his design of fuel treatment and handling/storage facilities to provide the requisite flow and quality of fuel to the gas turbines to ensure safe, efficient and reliable operation within the environmental limitations, under all operating modes and climatic conditions as defined in Section 2 of this Specification.

Interconnection to the existing gas supply line will be undertaken by the Contractor, to a location mutually agreed with the Owner/Engineer. This connection will be [ ].

The routing of the gas lines and scheduling of tie-ins shall be agreed with the Owner/Engineer to minimize disruption to the operations of the supply system.

6.2.1.2 Design capacity and operating range

The design flow rate (DFR) for the fuel gas system shall be the fuel flow required for the power plant (ie two gas turbine units) at conditions of maximum demand. The minimum flow shall be that required to maintain one gas turbine at minimum part load operation. The fuel gas system shall be designed to operate satisfactorily from minimum flow to DFR over the range of ambient conditions as defined in Schedule A.

For common systems supplying the power plant (ie two gas turbine units), 100 per cent duty equates to the design flow for both gas turbine units.

6.2.1.3 Scope of Work

The complete fuel gas handling and treatment system from the gas supply terminal point shall be the responsibility of the Contractor. The equipment provided shall be capable of removing contaminants from the fuel gas to achieve the required quality, and of supplying the required quantity, pressure and temperature of gas to each gas turbine at the required dry and clean conditions.

The fuel gas system shall be capable of delivering sufficient fuel gas to enable the gas turbines to operate, without restriction, at their design maximum capability over all specified operating and ambient conditions.

The main equipment shall include, but shall not be limited to the following:

a. Emergency shut down valve station controlled from the central control room

- 6.17 -


b. Gas compression station (if applicable), comprising three (3) × 50 per cent duty gas compressors, to provide the necessary pressure for the gas turbine units

c. Two (2) 100 per cent separator type gas scrubber units

d. Two (2) 100 per cent gas filter units

e. Two (2) 100 per cent metering streams for the determination of flow

f. One gas chromatograph meter to determine calorific value and density of the gas stream.

g. Two (2) 100 per cent heaters (if applicable), to condition the gas temperature to within required limits.

h. Two (2) 100 per cent pressure regulating valve streams, to condition the gas pressure to within required limits.

i. Gas condensate drains system

j. Gas venting/nitrogen purge system

k. Gas detection and alarm equipment, including portable gas detection equipment for gas line purge monitoring.

Notwithstanding the above list, it will be the responsibility of the Contractor to provide all equipment whether specifically detailed or not, to effect a fully functional gas supply system.

6.2.1.4 Design requirements

The design, installation and testing of the fuel gas supply system shall comply with the requirements of BS EN 14161 or equivalent internationally recognized standards and regulations applicable to the installation. The Contractor shall list the standards applied to main items of equipment and shall substantiate selection within the Tender.

The fuel supply systems shall comply also with all relevant NFPA or equivalent standards and special attention shall be paid to ensure increased safety against hazard due to fuel gas handling.

All equipment shall be designed with the primary consideration being reliability, ease of operation and a minimum of maintenance attention and shall operate satisfactorily under the full range of operating pressures, gas flow, gas temperatures and ambient temperature.

The Contractor shall take into account the composition of the gas in selection of the material specifications and demonstrate that the relevant codes have been adhered to.

The venting system shall serve as a safe removal system for all possible hydrocarbon vapours occurring during regular operations or emergencies. All vent gases shall be collected in a closed piping system which shall direct the gases to a venting stack, where they are vented safely.

- 6.18 -


The drains from gas scrubbers and gas filters and from other points shall be led to a common underground concrete pit from where the same will be pumped via effluent pumps to mobile tankers.

All gas vessel nozzles shall be flanged, and equipment shall be fitted with isolation valves to permit removal for maintenance without interrupting the gas supply.

A wire mesh security fence shall be provided to limit access to the gas filter/separators and pressure control equipment. A wire mesh security fence shall separately protect the gas heating equipment.

6.2.1.5 Emergency shut down valve station

An emergency shutdown fire safe flanged ball valve complete with pneumatic actuator and flame proof solenoid valve suitable for remote and local operation and fail safe shall be provided. This valve should be located as close as possible to the supply terminal point at the site boundary to protect the plant from overpressure in the gas supply pipeline.

6.2.1.6 Fuel gas compressor plant

The Contractor shall provide fuel gas compression plant if necessary to raise the fuel gas pressure from the minimum incoming pressure to that required for satisfactory operation of the gas turbines under all operating conditions.

[3 × 50] per cent duty gas compressors (two operational –one standby) shall be provided complete with all ancillary plant. Alternative gas compressor configurations will be considered if information is provided to substantiate the alternative. However, the base offer shall be compliant with the Specification.

The compressors shall be designed for long term continuous service at sustained full load, part load or at any combination of loads required by the gas turbine units. Heavy duty, water cooled, oil free type, reciprocating compressors in accordance with API 618 are preferred.

The compressors shall be skid mounted including intercooler, lubricating oil system, suction filter and controls etc. and shall be complete in all respects for safe and efficient operation.

The compressors shall be housed in a weatherproof but well ventilated enclosure(s). The location of the gas compressor enclosure(s) shall minimize the extent of pipework operating at high operating pressure.

Ventilation of the gas compressor enclosure(s) shall ensure that air intakes are situated a minimum of 3 m from any ignition source. High and low level ventilation openings to atmosphere shall be provided. All high level ventilation shall be located as close to the roof level as possible. The total effective ventilation area shall not be less than 2 per cent of the floor area of the enclosure.

Where mechanical ventilation is offered it shall be fully interlocked with compressor operation.

- 6.19 -


Where noise levels necessitate attenuation of the ventilators, any application of attenuation shall not reduce the effectiveness of the ventilators.

Enclosures shall be provided with a fixed gas detection and alarm system.

Anti vibration mountings shall be provided to reduce vibration and noise.

Remote indication shall be provided at the PCS for outlet cooling water temperature of all heat exchangers, oil cooler inlet and outlet temperature, bearing oil header pressure, gas temperature at the inlet and discharge of each compression stage, gas pressure for the compressor inlet and the discharge of each stage, and differential pressure across replaceable cartridge lubricating oil filters.

As a minimum the compressor shall shut-down under conditions of high compressor discharge temperature, high compressor inlet/discharge pressure, low lubricating oil pressure/high lubricating oil temperature and high vibration.

6.2.1.7 Fuel gas separator/scrubber

The separator equipment shall consist of two 100 per cent duty/standby high efficiency cyclone type scrubber units.

The scrubber shall remove 100 per cent of solid and liquid particles 8 microns and larger at DFR. The scrubbers shall be able to maintain the stated efficiency and remove particles from minimum flow to 100 per cent DFR, over the range of gas supply temperature and pressures when handling all specified types of fuel gases.

The design shall ensure low pressure drop across the separator, and prevent the passing of mist to downstream process equipment.

Corrosion allowance shall be determined by the Contractor based on the gas conditions, with a minimum allowance of 5 mm provided for the vessel, and a minimum of 2 mm allowance provided for piping connected to the separator vessel.

The scrubber station shall be provided with isolating valves, vents and drains, and shall be designed to allow changeover to the standby unit whilst on load.

Gas condensate shall be drained from the scrubbers to the gas condensate drains tank via automatic valves initiated by filter level equipment. High and low level instruments shall also be provided to alarm on the DCS.

6.2.1.8 Fuel gas filters

The gas filters shall be installed downstream of the gas scrubber. The filter shall include full bore quick closure with safety interlock bleed and fitted with drains sump.

The filter elements shall be replaceable, suitable for the specified gases and meet the necessary requirements for protection of the gas turbine units. The type selected will be supported by Contractor’s experience and documentary proof.

- 6.20 -


The minimum efficiency of the gas filter under normal operation shall be 100 per cent of all solid particles 3 microns and larger, and 99 per cent of particles from 0.5 to 3 microns, when handling all specified types of gases.

Each filter line shall be complete with all isolation, vent and drain valves, to allow changeover on load. The vessel shall include temperature and pressure gauges and differential pressure gauges, which shall alarm the operator that the filter in service requires cleaning and changeover to the standby filter is necessary.

6.2.1.9 Gas metering equipment

The Contractor shall provide tariff quality metering at the site boundary to enable the quality and flow rate of gas delivered to the site to be independently recorded.

The metering system shall be of approved type, and shall be designed to provide accurate measurement of the gas flows during all plant operational conditions, including the frequent starting and stopping of the plant during two shifting operating regime and at low loads.

The metering station will be complete with all instrumentation, valves, purge points, vents and drains. A gas chromatograph shall be provided to measure fuel calorific value of the fuel.

Two 100 per cent capacity flow metering streams shall be provided with an accuracy better than ±1 per cent over the full flow range of the metering station. The metering system shall include a flow computer to automatically correct the flow rate for pressure, temperature and composition (compressibility factor).

The meter shall be located such that sufficient straight lengths of piping are provided both upstream and downstream of the device.

6.2.1.10 Gas heating equipment

Heating of the filtered gas shall be provided (If necessary) to ensure that the gas is maintained at a level above its dew point to prevent the possibility of freezing of the pressure reduction valves.

Two 100 per cent capacity horizontal indirect/waterbath type heaters for fuel gas heating service shall be provided, complete with integral burners and control bypass, burner control panel, inlet and outlet isolating valves, vent, drain and purge facilities.

The system offered by the Contractor shall be suitable for the hazardous area classification for its location. The supply of gas to the heaters shall be tapped upstream of the unit gas flow-meters. The Tenderer shall provide details of the proposed system with the Tender.

6.2.1.11 Pressure control equipment

Two streams of pressure reduction/trimming shall be provided, each stream sized for the design flow rate (DFR) of both gas turbine units. One stream shall be operational feeding two gas turbines whilst the second stream is in standby.

- 6.21 -


Each stream will consist of two pressure reducing valves in series. The valves shall be of the self acting pilot type, and shall act to maintain the downstream pressure constant at the pressure required by the gas turbine making due allowance for pressure drop downstream of this equipment. In the event of the upstream pressure falling each pressure reducing valve should revert to its fully open position.

Each valve shall be designed to carry the full pressure reducing duty, one valve normally being the duty valve and designed to fail open. The second valve shall normally be the standby and be designed to fail closed.

The pressure reducing valves shall be controlled automatically to maintain the gas pressure within the required limits during normal operation and below the lifting pressure of the relief valves. Control range for each pressure reducing stream shall be from 5 to 110 per cent of the design flow rate (DFR). Valve opening at DFR shall not exceed 80 per cent.

Leakage rates shall not exceed 0.1 per cent of maximum CV value. Actuators shall be piston actuated type with air to open and spring to close. Fail safe position of the valve will be locked in position following instrument air failure, control signal failure, control power supply failure, etc.

The pressure reducing control valves shall be of an approved type and shall be perfectly stable, quiet and free from vibration in operation when operating at any flow up to the maximum flow and shall be suitable for continuous use at the operating temperature.

All streams shall be provided with upstream and downstream isolation of the pressure reducing valves. The upstream isolation shall comprise an automatic slam shut type valve together with a manual isolation valve.

A pressure-relief valve shall be provided on the outlet side of each reducing valve capable of exhausting to atmosphere the maximum discharge of the reducing valve without undue build-up of pressure on the low pressure side. The discharge from the relief valve shall be led to a common vent stack and discharged at a safe location. Alternatively the pressure relief valves will have their own vent stack. Pressure gauge and thermometers shall be provided upstream and downstream of the reducing valve.

All valves shall be provided with limit switches in the open and closed positions for remote indication or alarm purposes as required.

The pressure control station and all its associated equipment shall be designed to give the highest level of availability. The operation of the pressure control station shall be automatic over its complete flow and pressure range. Upon failure of a duty reducing valve or stream, the standby reducing valve or stream as appropriate, shall automatically commence operation in a bumpless manner.

6.2.1.12 Fuel gas condensate system

Gas condensate shall be collected from the filter/separators, unit filters and other relevant system drains into condensate collection tanks. These tanks shall be provided with two 100 per cent drain pumps for emptying the contents of the tank into road tankers for off-site disposal.

- 6.22 -


Each condensate tank shall be provided with suitable level controls/alarms, manholes, inlet, vent and drains connections.

6.2.1.13 Gas turbine equipment

In addition to the equipment provided in the common fuel gas supply line, the following equipment shall be provided on the individual gas supply pipelines to each gas turbine:

a. Gas turbine unit gas filtration

‘Fine’ filters shall be provided on the individual gas supply pipelines to each gas turbine. The filters shall be designed to remove all contaminants, solid and liquid to the specification as recommended by the gas turbine manufacturer

Each filter shall be capable of passing the full load flow of the gas turbine under the highest fouled pressure drop condition.

Each unit filter shall be complete with all isolation valves, and the filter vessels shall be designed for ease of filter element removal.

Gas condensate shall be drained from the filters to the gas condensate drains tank via automatic valves initiated by filter level equipment.

b. Gas turbine unit gas flow metering

Suitable flow metering devices shall be provided on each of the individual supply lines to the gas turbines. The meters shall be provided with temperature and pressure compensation, with local and remote readout facilities and totalizer.

6.2.1.14 Fuel gas pipework

All gas pipework shall be designed, constructed, installed and tested in accordance with ANSI B31.3 or equivalent internationally recognized standards.

All buried gas pipework shall be accommodated in trenches which are excavated, prepared and backfilled in accordance with BS EN 14161; the depth of cover over the crown of the pipe shall be not less than 900 mm.

A flexibility/stress analysis shall be carried out on the gas system during the detail design stage. The analysis shall demonstrate that the completed pipework system, including line equipment, is not over stressed or subject to excessive deflections, movements during installation, including hydrostatic testing, or during operation, including transient conditions, and the forces and moments on equipment do not exceed those specified by the manufacturer. Additionally, the effects on the fatigue life of the installation shall be shown to be acceptable.

All welds shall be subject to 100 per cent radiography.

The hydrostatic test of the pipework shall be carried out on completion of the installation at site. After completion of this test the pipework shall be dried out using dry compressed air and once dry inhibited with a slight pressure of nitrogen.

- 6.23 -


A system of ensuring the line is clean and suitable for use is to be proposed by the Contractor, (this may be by ‘pigging’).

Main equipment isolation valves shall be full-bore, trunnion-mounted double block and bleed type valves.

6.2.1.15 Vents and drains

Adequate provision shall be made for safely venting, purging, and where necessary, draining those sections of pipework and equipment which have to be isolated during construction, commissioning and maintenance.

The venting system shall be suitable for the disposal of vented or emergency relief gases. All vent gases containing hydrocarbon vapours, eg during stream purge on shut down operation, shall be piped to safe locations or to a vent stack.

Block and bleed with integral vent arrangements shall be provided, where necessary, to ensure plant safety, and purge vents shall include facility for connection of gas detection equipment.

Vents and drains only needed for tests shall be plugged and seal-welded; all others shall be equipped with blind flanged or blind plugged gate or ball valves. Vents and drains shall have a minimum diameter of 20 mm.

The vent system shall be designed to remove the largest amount of vent gas, which could occur during any reasonably assumed plant condition or emergency expected throughout the power station. Basic and detailed design shall be subject to Owner/Engineer’s approval.

6.2.1.16 Corrosion protection

All above ground fuel pipes shall be protected against corrosion in accordance with the Painting and Protection requirements defined in Section 6.7 of this specification.

Buried portions shall be protected against corrosion with factory applied coating and cathodic protection, suitable for the ground conditions.

The selection of coating and method of application shall be to the approval of the Engineer and shall be taken to ensure mechanical and electrical compatibility with the cathodic protection system.

6.2.1.17 Cathodic protection

Cathodic protection shall be applied by the impressed current method to all buried pipework. The cathodic protection shall be brought into operation immediately upon completion of the pipeline construction with the protection designed and installed in accordance with the requirements as defined in the Cathodic Protection, Section 8 of this Specification. Particular note shall be taken of the presence of other buried services in the area of gas pipeline and the procedures of BS 7361: Part 1 shall be followed.

- 6.24 -


6.2.1.18 Pressure vessels

All pressure vessels shall be designed in accordance to ASME Section VIII Div. 1 with latest amendments, and welding shall conform to ASME Section IX for welding as well as for welder’s qualifications.

All welds shall be 100 per cent examined by appropriate non-destructive technique. Radiographs shall be interpreted using the porosity charts in the above standard.

6.2.1.19 Inert gas purging

An inert nitrogen gas purging system shall be provided for the complete fuel gas system. Suitable valved connections shall be provided at all necessary points in the system to allow purging to take place.

The necessary nitrogen bottles shall be provided in suitable racks or ‘batteries’. Every battery shall have pressure gauge, thermometer, reducing valve, and a pressure relief valve downstream of the reducing valve. One hose connection with arrangement for quick connection for each battery shall be supplied. Hose length shall be not less than 7 m.

The Contractor shall provide a nitrogen storage area and sufficient spare nitrogen cylinders of the same type and make to enable two complete system purges.

6.2.2 Fuel oil supply system

6.2.2.1 Fuel oil supply

Fuel oil to the plant will be supplied from [ ].

Preliminary fuel oil supply conditions are provided in Schedule A for information.

The Contractor is responsible for obtaining sufficient data regarding the fuel supply conditions, including fuel analyses as necessary for his design of fuel treatment and handling/storage facilities to provide the requisite flow and quality of fuel to the gas turbines to ensure safe, efficient and reliable operation within the environmental limitations, under all operating modes and climatic conditions as defined in Section 2 and Schedule A of this Specification.

Interconnection to the existing fuel oil supply line will be undertaken by the Contractor, to a location mutually agreed with the Owner/Engineer. This connection will be [ ].

The routing of the fuel oil lines and scheduling of tie-ins shall be agreed with the Owner/Engineer to minimize disruption to the operations of the existing supply system.

6.2.2.2 Design capacity and operating range

The design flow rate (DFR) for the fuel oil system shall be the fuel flow required for the power plant (ie two gas turbine units) at conditions of maximum demand. The minimum flow shall be that required to maintain one gas turbine at minimum part load operation. The fuel oil system shall be

- 6.25 -


designed to operate satisfactorily from minimum flow to DFR over the range of ambient conditions as defined in Schedule A.

For common systems supplying the power plant (ie two gas turbine units), 100 per cent duty equates to the design flow for both gas turbine units.

6.2.2.3 Scope of Work

The Contractor shall provide a complete system to deliver fuel oil to the gas turbines, black start diesel generator, emergency diesel generator and diesel fire pump at appropriate supply conditions and quantity.

The scope of supply for the distillate fuel oil system shall include, but not be limited to, the following:

a. Fuel oil supply line; from supply terminal point to the fuel oil tank, including isolating valves, filtration and flow monitoring/sampling facility.

b. Fuel oil storage tanks : one [xx] m3 capacity ‘bulk’ storage tank and one [xx] m3 capacity ‘day’ tank, located in a bunded area.

c. Fuel oil conditioning/treatment plant (if necessary) : comprising 2 × 100 per cent treatment streams (duty/standby)

d. Fuel oil forwarding station, comprising duplex type strainers and 2 × 100 per cent capacity, centrifugal type distillate fuel oil forwarding pumps.

e. Fuel oil pressure regulating valves and accumulators, to maintain the fuel oil supply to the gas turbines.

f. Fuel oil flow monitoring:

One flow meter for measuring the distillate fuel oil supply to the black start diesel engine.

One flow meter for measuring distillate fuel oil supply to the emergency generator.

One flow meter for measuring distillate fuel oil supply to the diesel fire pump.

Two flow meters (one for measuring distillate fuel oil supply to each gas turbines)

g. Insulation or heating to ensure that waxing does not occur in cold weather (if applicable).

In addition, the Contractor shall provide all pipework, valves, air separators, filters, drains, drip pans, vents, fittings, trace heating and equipment needed to convey oil from the unloading point

- 6.26 -


to the consumers, and to convey recirculation oil back to the storage tank. All instrumentation shall be accessible via the PCS monitoring system.

6.2.2.4 Design requirements

All equipment shall be adequately sized and of material properly selected for the fuel as specified, and shall be designed, manufactured and installed in accordance with the appropriate international codes and standards, including BS, ANSI, ASME, API and local regulations as appropriate.

The fuel supply systems shall comply also with all relevant NFPA or equivalent standards and special attention shall be paid to ensure increased safety against hazard due to fuel oil handling.

All equipment and materials shall be easily accessible and suitable for outdoor installation. The Contractor shall provide all necessary access platforms, stairways and ladders to meet this requirement.

All equipment shall be designed with the primary consideration being reliability, ease of operation and a minimum of maintenance attention and shall operate satisfactorily under the full range of operating pressures, gas flow, gas temperatures and ambient temperature.

The Contractor shall take into account the composition of the fuel oil in selection of the material specifications and demonstrate that the relevant codes have been adhered to.

6.2.2.5 Fuel oil supply line

The Contractor shall provide a facility for filling the fuel oil storage tank from the existing fuel oil line.

The tank filling connection shall be provided with remotely operated isolating valves, controlled from local panel and the CCR. Automatic closing of the inlet valves shall be initiated by high level switch provided on the fuel oil tank

Two 100 per cent capacity distillate fuel oil strainers shall be provided with quick release covers and isolating valves to provide for uninterrupted flow of oil during cleaning of a strainer. Baskets shall be of stainless steel with the open area not less than six (6) times the cross sectional area of the suction pipe supplying the strainer. Each strainer shall be provided with local differential pressure indication and a transmitter for remote indication. An alarm shall be installed to remotely indicate when the maximum allowable pressure drop is reached.

One flow measuring device shall be provided for monitoring instantaneous as well as integrated fuel oil delivery flow, both locally, and at the CCR. The flow monitoring station shall have facility for sampling of the fuel oil.

6.2.2.6 Fuel oil storage tanks

The Contractor shall supply and install one fuel oil bulk storage tank, [and one fuel oil day tank]. The tanks shall be vertical cylindrical type, designed, manufactured, constructed and tested in accordance with the requirements of API 650.

- 6.27 -


The bulk storage tank shall have a net storage capacity to cover for not less than [7] days operation of the plant, based on maximum fuel oil consumption rate of both gas turbines.

[The ‘day’ tank net capacity shall be sufficient to provide [12] hours operation of the plant, based on maximum fuel oil consumption rate of both gas turbines].

The tanks shall be installed in an impermeable containment bund sized to contain as a minimum 110 per cent of the entire contents of the largest tank located within the bund. There shall be no bund wall penetration and all pipe work and cabling shall be routed over the bund wall.

Each shall be complete with stairs, handrails, internal and external coatings, instrumentation, vents, manholes, drains, filling and extraction pipework, and any other equipment necessary for the safe operation of the fuel oil system. As a minimum, the following connections and equipment shall be provided:

a. Filling connection fitted with screw down non-return valve and motorized shut-off valve.

b. Floating suction connection, complete with motorized isolating valve.

c. Fuel oil recirculation connection, fitted with screw down non-return valve and isolation valve.

d. Water draw-off sump, positioned at the lowest point on the tank.

e. Clean out door, complete with suitable davit arm support.

f. Atmospheric vent close to the roof apex, sized for the maximum rate of filling or emptying with a 10 per cent margin, with domed cover and flame arrester.

g. Four earthing terminals suitable for connection to the existing grounding system.

h. Lightning and static protection.

i. A spray water pipe system erected around the perimeter on top of the tanks and connected to the fire fighting hydrant main.

j. Four foam injection points.

k. One 600 mm diameter roof manhole, with hinged cover and padlocked grill inside the manhole opening.

l. One 600 mm diameter shell manhole, with bolted over, located 1 m above ground level.

m. Float type tank level measuring instrumentation for local and remote indication via the PCS (level indication and high level alarm)

n. High level switches and an alarm system with display local to the tanker unloading point and at the CCR

- 6.28 -


o. Lockable dip hatch (minimum dia 200 mm) located adjacent to the stairway access, complete with two off graduated steel dip tapes

p. Access stairways from the bunded area to the top of the fuel oil tank

The tank filling connection shall be arranged in such a way as to avoid stirring up any material that may have settled on the tank bottoms, and shall include a velocity diffuser to minimize the jet effect of the incoming fuel. The floating suction connection shall be have the travel restricted such that the inlet is never less than 500 mm from the tank bottom. A check chain shall be provided to limit the height of suction travel with a cable supplied to permit the operation of the floating suction arm to be checked.

6.2.2.7 Fuel oil treatment plant (if necessary)

The Contractor shall be responsible for selection of the appropriate treatment process and the provision of all equipment and systems necessary to ensure that the fuel oil is delivered to the plant in accordance with the quality requirements of the gas turbines.

[Two 100] per cent treatment streams shall be provided, operating on a duty/standby basis. The net capacity of each stream shall be sufficient to supply treated fuel for both gas turbines operating at maximum load on fuel oil.

[Two 100] per cent distillate fuel oil transfer pumps shall be provided, to transfer fuel oil from the bulk storage tanks to the fuel oil day tank, via the fuel oil treatment plant. Duplex strainers shall be provided at the inlet to the transfer pumps; the design of the strainer units shall be identical to those supplied for the fuel oil forwarding pumps.

6.2.2.8 Fuel oil forwarding pumps

[Two 100] per cent capacity centrifugal type distillate fuel forwarding pumps shall be provided. Each fuel oil forwarding pump shall be capable of delivering the specified fuel oil at an appropriate pressure and quantity for the simultaneous operation of all consumers. The Contractor shall take into consideration all pressure drops in the system caused by elevation differentials, friction in the pipeline, filters, heaters, meters, strainers and control valves.

Each pump shall be protected by a relief valve set so that the minimum flow requirements of the pump are met at all times, the discharge of the relief valve shall be returned to the suction side of each pump.

The Contractor shall submit performance curves and supporting calculations to substantiate the pump selection with his detail design.

The fuel oil forwarding pumps shall be located in a building adjacent to the fuel oil storage tank area. The Contractor shall provide suitable trays or containment for the collection of any seepage emanating from the pumps.

Duplex strainers shall be provided at the suction of the fuel oil forwarding pumps, designed to provide for uninterrupted flow of oil during cleaning of a strainer. Baskets shall be of stainless steel with the open area not less than six (6) times the cross sectional area of the suction

- 6.29 -


pipe supplying the strainer. All strainers shall have pressure ratings appropriate for the service intended, but in no case, less than 1.5 times the maximum service pressure. Each strainer shall be provided with local differential pressure indication and a transmitter for remote indication. An alarm shall be installed to remotely indicate when the maximum allowable pressure drop is reached.

6.2.2.9 Fuel oil pipework, valves and fittings

All fuel oil pipework shall be designed, constructed, installed and tested in accordance with ANSI B31.3 or equivalent internationally recognized standards.

All buried fuel oil pipework shall be accommodated in trenches which are excavated, prepared and backfilled in accordance with BS EN 14161; the depth of cover over the crown of the pipe shall be not less than 900 mm.

All isolating valves in the fuel oil systems shall be of the non-lubricated ball type with Teflon seals and resilient faces, where applicable. The valves shall be of the fire-safe design. Threaded valves shall only be used where required for equipment compatibility. Cast iron valves shall not be used for oil service.

All piping and equipment shall be protected against excess pressure utilizing pressure relief valves. Over pressurization of blocked or isolated pipelines and equipment by solar heating and ambient temperature changes shall be considered in the design. Relief valve discharge shall be piped to the return header or pump suction, as required.

Vents and drains equipped with a ball valve shall be provided at strainers and all high points and low points respectively. In addition, connections required for periodic tests shall be equipped with valves and threaded nipples which shall be protected by threaded caps.

6.2.2.10 Pressure accumulators

Pressure accumulators shall be provided by the Contractor, if considered necessary to maintain fuel oil supply pressure during a switch from a duty to standby pump. The pressure accumulators shall be located in the pump discharge header, and shall be designed for operation under all possible operating combinations of pumps.

6.3 Water supply and waste water systems

6.3.1 General

Raw water to the plant will be supplied from [ ].

Preliminary raw water supply conditions are provided in Schedule A for information.

The Contractor shall be responsible for designing and installing water handling, storage, treatment and distribution systems as necessary to provide the requisite flow and quality of water as required for the complete power station.

- 6.30 -


Raw water shall be used to supply all the process water requirements of the power station, including service water, fire water, demineralized water, and potable water for domestic purposes.

A comprehensive site water balance showing all water demands and effluent discharge pathways shall be provided to demonstrate the adequacy of the plant provision.

6.3.2 Scope of work

The complete water supply system from the raw water source to all water consumers, and the and waste water system to the final disposal point shall be the responsibility of the Contractor.

The scope of the water systems shall include but not be limited to the following:

a. Raw water supply system, including pumping, treatment and distribution

b. Service water (treated raw water) system, including storage, pumping and distribution

c. Demineralized water system, including water treatment plant, storage, pumping and distribution

d. Potable water system, including water treatment plant, storage, pumping and distribution

e. Waste water system, including treatment, storage, monitoring and disposal.

Notwithstanding the above list, it will be the responsibility of the Contractor to provide all equipment and services whether specifically detailed or not, to effect a fully functional water supply

6.3.3 Raw water supply

Raw water shall be pre-treated to ensure that it is suitable for use as site service water, and transferred via a pipeline to the service/fire water storage tank at the site. Service water shall be used as the source for production of demineralized water and potable water for the plant.

An indicative analysis of the raw water is included in Schedule A for information. The Contractor is responsible for obtaining his own raw water analyses as the basis for his design of water treatment plant and storage facilities, including all necessary explorations, sampling and analysis in order to ensure that the proposed plant design is appropriate to the supply conditions.

6.3.4 Service water

6.3.4.1 Service/fire water storage

A combined service/fire water storage tank shall be provided to supply buffer storage capacity in the event of a temporary loss of raw water supply. The tank shall be vertical cylindrical type with conical fixed roof, designed in accordance with BS 2654 and installed on a concrete foundation.

- 6.31 -


The service water section of the tank shall have a storage capacity to cover [24] hours of the station water requirements at maximum demand.

The capacity of the fire water section of the tank shall be based on the maximum anticipated flow rate for the largest single risk associated with the power station plus the demand for two hydrant points, for a period of two hours in accordance with the requirements of NFPA 850.

The tank shall be constructed of carbon steel and shall be painted fully, inside and outside (including underside of bottom plate), the painting system shall be in accordance with Section 6.7. The minimum thickness of steel plate shall not be less than 8 mm including corrosion allowance. The tank shall be provided with flanged connections for all external piping. All tank connections shall be protected by suitably reinforced rubber expansion joints, and shall be cathodically protected in accordance with Section 6.8.

The Service water connections, including connection to the water treatment plant shall be arranged to ensure that the dedicated fire water reserve is maintained within the tank at all times.

The tank shall be located adjacent to the water treatment plant and fire water pump houses, and shall be complete with all necessary connections for make-up, overflow, vent and drain, water treatment plant suction, fire pump suction including vortex inhibitor, pump re-circulation and testing, level indicator, level transmitters and high/low level switches for control/alarm/trips as necessary, access manholes in side wall and roof, complete with access ladder, handrails, and a dosing system to inhibit microbial growth.

All necessary tank fittings, instrumentation and access shall be provided in accordance with NFPA 22.

The make up to the tank shall be sized to comply with the fire water storage replenishment requirements as laid down in NFPA 850, ie capable of replenishing the fire fighting capacity of the tank within 8 hours. The make up valve shall be operable from the CCR, with position indication.

The tank vent(s) shall be sized to cover the air ingress commensurate with the maximum tank inflow/outflow conditions.

6.3.4.2 Service water distribution

The Contractor shall provide a fully functional service water system that is sized and arranged to support all plant requirements for wash down and make-up throughout the plant.

The service water system shall comprise two 100 per cent capacity service water pumps, together with all necessary piping, valves and fittings to distribute Service water throughout the plant.

Appropriate building or shelter shall be provided to house the pumps etc to enable ease of maintenance and afford general protection from the environment. Hoists and other equipment needed to maintain these pumps shall be supplied by the Contractor.

- 6.32 -


The system shall be suitable for continuous full load operation under all climatic conditions, and all materials used shall be carefully selected to resist to the greatest extent possible the erosive and corrosive effect of the distilled (product) water used in the system.

The pump casing shall be constructed of cast iron and the pump impeller, wear rings, shaft and shaft sleeves shall be constructed of 316L stainless steel unless otherwise approved by the Owner/Engineer. Pumps shall be protected by suitable duplex filters and shall include all valves and instruments to alarm and facilitate changeover on load.

Pumps shall be arranged for automatic starting in the event of a loss of duty pump.

6.3.5 Demineralized water

The demineralization plant shall provide the total demineralized water requirements for the plant provided under this Contract. The treatment plant capacity shall include adequate provision to supply demineralized water for potable water treatment, NOBxB water injection, washing of each gas turbine compressor (based on washing each turbine twice per week), and for filling and make-up to the closed circuit cooling water systems. The water treatment plant design shall be based on not less than two [100] per cent streams. Details of the water treatment plant design, including water balance at each stage in the chosen demineralization process together with storage facilities shall be provided to demonstrate the adequacy of the plant provision.

The quality of the final treated water at any time when delivering water to service or to storage shall be as follows:

Contaminants Units Demineralized water quality

Conductivity C µS/cm <0.2

Sodium and potassium (Na, K) ppm (wt) <0.02

Silica (SiOB2B) ppm (wt) <0.02

PH 6 - 9

Adequate monitoring and control instrumentation shall be installed to allow automatic

operation of the plant and demonstrate the quality of the final product water. Normal operation of the plant will be from the PCS operator interface to the CCR. Manual override shall be possible from a local control panel. Alarms and indications shall be displayed both locally and in the CCR.

In addition to the automatic valves, manually operated lockable isolating valves shall be provided to allow any plant stream to be taken out of service while parallel streams remain in service.

A final water quality monitor (conductivity) shall be included that can activate an interlock system to prevent the forwarding of poor quality water. A silica monitor shall be included on the final treated water outlet.

Plastic pipe shall not be used to convey chemical reagent solutions of >5 per cent w/w strength or where the fracture of the pipe could pose danger to personnel.

- 6.33 -


Effluent storage facilities shall be capable of receiving the wastewater from the demineralization process for a minimum of [12] hours continuous operation. Equipment shall be included for the mixing and automatic neutralization, to a pH range of 6-9, of all effluent generated prior to its discharge. Facilities shall be included for recording the pH of all effluent discharged. Details of the quantity and quality of effluents produced shall be given. Details of the disposal route for the neutralized effluent shall be provided.

The Contractor shall build-in sufficient redundancy such that repair, maintenance and isolation of plant may be carried out without process interruption.

Adequate manual sampling points shall be provided to allow monitoring of the plant's performance.

All precautions shall be taken in the design and layout of the plant to avoid danger to personnel. Adequate safety equipment (showers, eye baths) shall be provided at all locations where an occupational hazard exists.

Activation of any safety shower shall initiate an alarm in the main CCR.

6.3.5.1 Demineralized water storage

The demineralized water storage tank shall be vertical cylindrical type with conical fixed roof, designed in accordance with BS 2654 and installed on a concrete foundation.

The tank shall have a storage capacity to cover for not less than [48] hours demineralized water consumption of the plant at maximum water demand, based on both gas turbines operating at full load on fuel oil.

The tank shall be complete with all necessary connections for make-up, overflow, vent and drain, potable water treatment plant suction, level indicator, level transmitters and high/low level switches for control/alarm/trips as necessary, access manholes in side wall and roof, complete with access ladder and handrails.

6.3.6 Potable water system

6.3.6.1 General

Potable water for domestic purposes shall be based upon not less than [300] litres per person per day, with [15] personnel on site at any on time. The system shall comprise, but not necessarily be limited to, treatment, storage and distribution of potable water for the site.

The plant is to provide the total potable water requirements, with adequate margins for all personnel within the power station under all conditions of operation. Details of the plant design throughput sizing, redundancy and potable water storage facilities shall be provided with the Tender to demonstrate the adequacy of the plant provision.

The potable water treatment system shall take feed from the demineralized water tank, and shall include equipment for disinfection and for the adjustment of pH and hardness, as required, such that the supply conforms to WHO guidelines. Adequate monitoring and control instrumentation

- 6.34 -


shall be installed to allow automatic operation of the plant and demonstrate the quality of the final product water. Normal operation of the plant will be from the PCS operator interface in the CCR. Manual override shall be possible from a local control panel. Alarms and indications shall be displayed locally with essential alarms and indications conveyed to the CCR.

The equipment shall be complete with all associated pipe-work, valves, tanks, pumps, control and instrumentation necessary for the efficient and safe working of the system.

6.3.6.2 Scope of supply

The Contractor shall provide a comprehensive potable water system designed to provide a reliable, clean and appropriate quantity of water to all occupied buildings. The potable water system shall include all necessary pipework, tanks, filters, fittings, supports, metering and valves and shall be supplied in a fully commissioned and tested condition.

The Contractor shall ensure that the system complies with all applicable local water authority requirements and regulations.

This section of the Specification should be read in conjunction with Section 9, which details earthworks, concrete, masonry, sanitary ware and plumbing in buildings.

6.3.6.3 System description

The potable water treatment system will be fed from the [demineralized water tank], and shall deliver water into a main potable water storage tank. From the main tank, booster pumps will supply the potable water to points of use in each building and roof mounted portable water tanks via a buried pipework distribution system.

The potable water plant shall be located in the water treatment building, and shall include redundant streams to ensure security of supply to the station. The potable water supplies within the buildings is covered separately under Section 9, civil plumbing.

Pressure gauges shall be provided inside each building at the entry point of the potable water pipework.

6.3.6.4 Main potable water storage tank/booster pumps

GRP insulated/bolted sectional potable water storage tank or tanks shall be supplied for potable water storage, and located in the water treatment building. The tanks shall have a storage capacity to cover for not less than [48] hours at maximum potable water demand with no make up.

The tanks shall be of reinforced fibre glass ribbed construction, complete with openings and connections for cold water filling, overflow, drain, take off points, vent pipe and access for cleaning and inspection. The access cover shall be securely fixed to the tank and shall be fitted with a padlock and hasp.

The design and materials shall be suitable for a water temperature range of 5°C and 60°C.

- 6.35 -


The booster pumps shall be located adjacent to the tank, and shall be duty/standby configuration with facility to control the discharge pressure between 3 to 3.5 bar.

6.3.6.5 Potable water distribution

Refer to the General Mechanical section for requirements in regard to distribution piping, valves and fittings.

Before water distribution systems are placed in service all shall be completely cleaned by water, filling and flushed to ensure that no foreign matter remains inside the pipe.

During the cleaning process the Contractor shall disinfect the pipelines in accordance with the AWWA Specification No C 601 and to the satisfaction of the Owner/Engineer. The cleaning process shall continue until the water coming from the wash-outs or other branches is clear and free of taste or smell.

The Contractor shall supply all water, disinfection materials, equipment and labour required for this work.

6.3.6.6 Potable water storage

Roof-mounted water tanks shall be provided as required for all major occupied buildings/facilities and plant areas.

The tanks shall be of reinforced fibre glass ribbed construction, complete with openings and connections for cold water filling, overflow, drain, take off points, vent pipe and access for cleaning and inspection. The access cover shall be securely fixed to the tank and shall be fitted with a padlock and hasp.

The required material shall be suitable for a water temperature range of 0°C to 60°C and covered by a minimum 10 year guarantee.

The tank filling connection shall be connected to a float operated valve which shall be accessible from outside the tank for maintenance. The metal parts shall be corrosion resisting gunmetal, rubber components shall vulcanized rubber. The float shall be suitable for operating in temperatures in excess of 60°C. A tank bypass connection shall be provided to allow mains water to supply directly all points of use when the tank is out of service. The control valve shall be lockable. An emergency fill connection for water tanker use shall be provided for each building/facility, the fill connection shall be provided with an isolating valve in a stainless steel box.

6.3.7 Chemicals

A bulk chemical storage facility shall be provided for reagents for use in the closed circuit cooling system, the water treatment plant, potable water supply, all effluent treatments, the laboratory, and raw water pre-treatment. The system design shall minimize chemical handling by site operators. A comprehensive site chemical balance showing all chemical demands, details of chemical plant design and strategic chemical storage facilities shall be provided to demonstrate the adequacy of the plant provision.

- 6.36 -


All bulk chemical reagents shall be adequately stored and handled. Bulk storage facilities shall accommodate [28] days supply of chemicals at design consumption in either bulk tanks, on pallets or 1mP

3P "Intermediate Bulk Containers" (IBCs). The equipment shall be compliant with

appropriate International Standards. The storage facilities should be sufficiently labelled to identify the type of chemicals stored. Material Safety Data Sheets shall be made available for all purchased proprietary products.

The system design shall minimize chemical handling by site operators. All bulk storage chemicals and filling points shall be located in bunded areas. The bunds shall be sized to accommodate 110 per cent of the chemical contents as a minimum. The bunds will be coated with a suitable protective lining on the inner surfaces. Facilities shall be included for the controlled emptying of the bunded areas. The floor drainage system shall be designed to accommodate an accidental release of chemicals from the delivery tankers during discharge to the storage tanks. The drains system shall be designed to avoid the accidental mixing of incompatible chemicals. Information on the drainage facilities shall be provided.

Incompatible chemicals shall not be stored in the same bunded area.

The storage facilities shall, if required, be fitted with access ladders, platforms, vents and access ports. Level and contents gauges shall be visible from the unloading point.

Adequate vehicular access shall be provided to the storage facility to allow safe access of delivery tankers.

All pumps used for the mechanical forwarding of chemicals shall be housed within the respective tank bunded area on raised platforms to avoid any possibility of flooding. The pumps shall have adequate access and be suitably protected from the elements.

A demineralized water supply shall be provided for service use at the storage stations.

Storage facilities shall be fitted with suitable fume dispersion equipment as necessary.


Activation of any safety shower shall initiate an alarm in the CCR.

6.3.8 Laboratory

A laboratory shall be provided and be fully equipped to safely monitor all of the parameters required for the efficient operation of the power station.

All furnishings including bench-space, seating, services, fume-cupboards, facilities, security and instrumentation shall be provided. All consumable items including chemicals, reagents and batteries required up to takeover shall be supplied. Secure storage for chemicals shall be included. The laboratory shall contain equipment to enable all monitoring, investigative and quality requirements of the power station to be carried out. It shall include the condition and quality of all

- 6.37 -


effluents, water quality, atmospheric emissions and the condition of lubricating, hydraulic and fuel oils. Portable equipment shall be provided for testing and sampling.

All precautions shall be taken in the design and layout of the laboratory to avoid danger to personnel. Adequate safety equipment (showers, eye baths) shall be provided at all locations where an occupational hazard exists from chemical handling. Material Safety Data Sheets shall be made available for all purchased proprietary products and reagents.

6.3.9 Waste water systems

A site effluent disposal system is required to ensure that all potentially contaminated wastes generated by the construction, operation and maintenance of the power station shall be controlled in accordance with World Bank guidelines and local legislation.

The wastewater generated by the water treatment plant will be controlled prior to discharge to the surface water drainage system as defined in the water treatment section of this specification. Effluent from the drains of the laboratory, battery room, and chemical dosing drains shall also be suitably treated.

Surface water with the potential of oil contamination shall be directed to an oil/water separator prior to discharge. All waste oil shall be collected for off-site disposal.

Gas turbine compressor wash effluent shall be segregated and stored at a suitable location for off-site disposal.

Sampling and instrumentation shall be included in the final discharge to ensure compliance with the requirements of relevant legislation. As a minimum, this shall include equipment to measure flow, temperature and pH. Provision to take a manual sample shall be provided. Discharge of wastewater outside agreed limits shall be prevented by the control system.

For sites where no discharge sewer is available, the final effluent disposal may be routed to an evaporation pond. Details of the proposed discharge system shall be provided within the Tender.

For further details of the site waste water systems, refer to Section 9 of this Specification.

6.3.9.1 Packaged sewage treatment plant

A packaged sewage treatment plant shall be provided to cater for the total foul water treatment requirements of the station, with adequate margins, under all conditions of operation. The plant shall be complete with sanitary drainage piping, manholes and grease traps required for conveying sewage, comminutor and bar screen, pre-engineered activated sludge modules, chlorination equipment, treated sewage holding facility, treated sewage transfer pump sets, interconnecting piping valves and supports, associated instruments and controls, associated electrical work, associated civil work and all tanks shall be fitted with access ladders, platforms, vents and access ports. Level and contents gauges shall be located for operational convenience.

- 6.38 -


The plant shall be capable of treating [300] litres per day of raw sewage per person during normal operation together with a provision for peak demand at [2.5] times normal operational flow.

The quality of the final effluent shall be:

Total suspended solids less than 30 mg/l

Total BOD less than 20 mg/l

The chlorination facility shall be capable of providing a free chlorine residual of 1 ppm; however, final discharge levels shall not exceed World Bank or local guidelines.

Where no discharge of the product affluent is available the treated discharge shall be pumped to an evaporation pond. The civil engineering requirements are defined in Section 9 of this Specification.

Adequate monitoring and control instrumentation shall be installed to allow automatic operation of the plant and demonstrate the quality of the final product water. Normal operation of the plant will be from the PCS operator interface to the CCR. Manual override shall be possible from a local control panel. Alarms and indications shall be displayed locally with essential alarms and indications conveyed to the CCR.

Details of the disposal route for the solid effluent shall be provided.

The Contractor shall build-in sufficient redundancy such that repair, maintenance and isolation of plant may be carried out without process interruption.

Adequate manual sampling points shall be provided to allow the monitoring of the plant's performance.


Activation of any safety shower shall initiate an alarm in the Central control room (CCR).

6.4 Closed circuit cooling water system

6.4.1 General

Unitized closed circuit cooling water systems shall be provided to supply cooling water for the gas turbine generators, gas turbine lubricating oil systems (where necessary), air compressors, gas compressors (if required) and any other equipment requiring cooling water. Each system shall be designed to have sufficient capacity to provide the cooling water requirements with the plant operating at peak load at the maximum ambient conditions.

- 6.39 -


The design, manufacture, installation and testing of the equipment shall be in accordance with the requirements and recommendations of all appropriate internationally recognized and accepted codes and standards.

Each cooling system shall be of the pumped closed type and utilize air-blast (fin-fan) type coolers to dissipate the heat generated within the system. The system shall be sized to operate over all operating conditions with the plant operating at the most onerous combination of ambient conditions.

6.4.2 Scope of Work

The minimum scope of work for each unitized closed circuit cooling system (one cooling circuit per gas turbine) shall include:

Two (2) 100 per cent capacity closed circuit cooling water pumps with suction filters

Heat exchanger(s) for all systems

[One (1)] air-blast heat exchanger with a minimum of one spare fan

One (1) expansion tank, all related pipework, valves and make-up water connections

One (1) chemical dosing facility.

Notwithstanding the above list, it will be the responsibility of the Contractor to provide all equipment and services whether specifically detailed or not, to effect a fully functional cooling water system.

6.4.3 System design and operation

The closed circuit cooling water system shall be filled with demineralized water to which a suitable corrosion inhibitor has been added. A manually operated chemical dosing facility incorporating mixing tank and injection pump shall be provided to maintain water quality. The Contractor shall provide facilities to ensure that when the cooling water system requires draining for maintenance the system can be safely discharged in accordance with relevant environmental guidelines.

A pressure gauge shall be provided and connected to the circulating water branches so that the pressure of both the inlet and outlet side of the heat exchanger may be ascertained.

The system shall be suitable in every respect for continuous full load operation over the full specified range of ambient and electricity supply conditions and shall be arranged such that during normal operation, the cooling water cycle shall be supplied by one (1) operating cooling water pump circulating treated demineralized water through the air blast heat exchanger to all equipment consumers requiring a cooling medium for their operation.

The control system shall be such that first (duty) cooling water pump shall be started automatically via the plant control system after flow has been established through the cooling water

- 6.40 -


heat exchanger. The second (standby) pump shall be started automatically on low pressure in the cooling water supply header or on trip of the duty cooling water pump motor.

The Contractor shall assess the need for and if necessary provide automatic modulating flow control valves on the system coolers. Any item supplied with a manual flow control valve shall be provided with a locking device and shall be set during system commissioning and require minimal manual adjustment over the lifetime of the plant. These valves shall not be used as isolation valves.

Fin-fan coolers shall have adequate redundancy of fans such that failure of a single fan shall not compromise system operation or the ability to generate at full capacity.

All materials used in the system shall be suitable for use with inhibited demineralized water. Copper alloy materials shall not be used in the manufacture of components in contact with cooling water.

Where closed circuit cooling water systems serve the instrument and service air compressors, each compressor shall be furnished with a power operated valve in its cooling water return line, interlocked to open on the “start compressor” signal to prevent condensation in the cylinders caused by cooling water flow when the compressors are idle. The compressed air system shall have its own cooling water system.

“Oil in water” monitors shall be provided where necessary to detect potential oil leak and raise an alarm to the PCS.

The system shall cater for short time loss of power supplies during supply changeover or pump trip on load. The system shall also permit a safe rundown of the plant with loss of main ac. supplies. The Contractor shall demonstrate that safe temperatures are maintained under these circumstances.

6.4.4 Air blast cooler

The blast air cooler shall be designed and manufactured in accordance with internationally recognized codes, including TEMA or equivalent. The Tenderer shall highlight the features incorporated into the design of the equipment, considering the air conditions at site.

Cooler fans shall be provided such that it is possible to isolate and maintain any one fan and motor whilst leaving at least 100 per cent cooling capacity in service over the full operating and ambient temperature range.

In addition, the cooler design shall incorporate 20 per cent additional surface on the water side as an allowance for fouling of the tube bundles.

Cooler headers shall be arranged so that access may be obtained to both ends of every tube without removing the header or cover. Vent and drain connections shall be provided and fitted with valves and equipped with padlocks.

Platform access shall be provided to all areas of the cooler plant including the elevated fan units for maintenance.

- 6.41 -


Air blast coolers shall be fitted with low noise fans and provided with sound attenuators as necessary to meet the noise levels specified in Section 2.

Proper consideration shall be given to the location of the air blast cooler in relation to other coolers on transformers etc. to avoid recirculation of hot air.

The cooler shall be complete with fans, motors, thermometer pockets, local thermometers, pressure gauges, vibration monitoring for all fans (with alarm to PCS), inlet and outlet isolating valves, automatic and manual air vents and drain valves.

6.4.4.1 Cooling water pumps

The delivery head of each cooling water pump shall be designed to meet all plant cooling water requirements. The pumps shall be identical and capable of parallel operation under all load conditions. Pump design capacity and design calculation shall be submitted to the Owner/Engineer for approval. All pump materials shall be selected with consideration to the properties of the medium transferred. Impeller shaft and shaft sleeves shall be of stainless steel.

The pumps shall be of the horizontal split casing and centrifugal type with fully balanced impellers and at least two bearings. The driving motor shall be mounted on the extension of the pump bed-plates and shall drive the pumps directly through flexible couplings, which shall be provided with removable coupling guards.

The pumps shall be standard units of a reputable manufacturer and shall conform to the general mechanical requirements prescribed in this Specification. The Contractor shall provide, with his detail design information, pump performance curves to demonstrate pump capability. Each pump shall be fitted with a simplex suction filter.

Where grease points are necessary they shall be fitted with removable screwed plugs which shall be accessible without removing guards. Bearings shall be of the oil lubricated rolling element type. All bearings having automatic lubrication shall also have provision for hand lubrication

6.4.4.2 Cooling water heat exchangers

Heat exchangers shall be furnished complete with vents, drains, filters, support saddles, lifting lugs and all necessary connections, studs and bolts. The exchangers shall be designed, manufactured and installed in accordance with recognized internationally acceptable standards and be suitably rated to accommodate the maximum duty derived from the most onerous operating conditions.

Tube and plate thicknesses shall be according to applicable code requirements and shall be subject to the approval of the Owner/Engineer.

Heat exchangers shall be furnished complete with removable water box covers, vents, drains, filters/strainers, support saddles, lifting lugs and all necessary connections, studs and bolts.

- 6.42 -


6.4.5 Header tank

A constant inlet pressure to the system shall be provided by means of the cooling water expansion tank. Water losses shall be compensated by filling the cooling system with demineralized water via the cooling water expansion tank.

The tank shall be equipped with a level indicator and with high and low level alarms. The make-up connection shall be equipped with a flow alarm announcing high make-up flow. A make-up line, regulated by an automatic water level controller, shall be supplied between the expansion tank and the nearest demineralized water supply line

The cooling water expansion tank shall be large enough to compensate for level variations during the start-up (heat up) and shut-off (cool down) of the system.

The expansion tank shall operate at atmospheric pressure and shall be located at the highest point in the system. The vent to atmosphere shall have a liquid seal to prevent air from continuously entering the tank.

6.4.6 Cooler controls

The closed circuit cooling water system fans and pumps shall be automatically started as part of the gas turbine generator start up sequences. Interlocks shall prevent operation without the appropriate cooling system in service. The number of fans in service shall be automatically controlled by signals from temperature sensors in the cooler discharge. Alarms shall be provided to operate on failure of any fan or pump and in addition to indicate abnormal temperatures, loss of flow, leakage etc. Where appropriate standby plant shall be started automatically.

6.5 Fire protection and detection

6.5.1 General requirements

All plant and buildings shall be designed and arranged to minimize the possibility of fire hazards originating from them or spreading to them from a fire in the vicinity. Plant and cables shall be segregated to reduce fire risk, damage and multiple shutdowns.

Electrical equipment located in hazardous areas shall be explosion proof, flame proof, intrinsically safe or otherwise designed to be suitable for the location zone.

The Contractor shall provide all calculations for all of the fire protection systems; conduct the design, procurement, equipment and system installation and subsequent testing. All shall comply with the applicable NFPA and related Code requirements, applicable national and local Codes and Standards and local Fire Department (FD) regulations and shall be subject to approval by the Owner/Engineer.

All equipment and valves etc shall be FM and UL approved and listed.

- 6.43 -


6.5.2 Scope of Supply

The scope of the fire protection and detection system shall include but not be limited to the following:

a. fire fighting water supply system, comprising fire water storage (dedicated reserve of raw water tank), main electrical motor driven and standby diesel engine driven pumps, jockey pumps, and Fire water mains;

b. automatic water spray deluge protection for all oil filled transformers and cable floors;

c. automatic water sprinkler system for stores and workshop;

d. automatic foam/water spray deluge protection for fuel oil pump house;

e. remote/local manually initiated foam protection for the fuel oil tanks and the bund area and spray cooling water system for fuel oil tanks;

f. standpipe and hose reel/hose rack cabinet system in the buildings and plant areas;

g. yard hydrants and yard hose cabinets;

h. gas extinguishing fire protection system for gas turbine enclosures, switchgear rooms, panels, instrument room and control rooms;

i. fire protection system for fuel gas scrubber and boosting station;

j. portable extinguishers in all the buildings;

k. comprehensive site fire detection system with master alarm panel in Control Room and repeater panel in gatehouse.

6.5.3 Fire water supply

6.5.3.1 Fire water storage

Water for fire fighting purposes will be treated raw water. An indicative analysis of raw water is provided in Appendix C.

A dedicated reserve of water for fire fighting shall be stored in a combined raw/fire water tank – refer to Section 6.3 for details.

6.5.3.2 Fire water pumps

One 100 per cent duty electric motor driven pump and one 100 per cent duty diesel engine driven pump shall be supplied, each pump capable of supplying water to all sprayers, sprinklers, hydrants or hose reels associated with the largest single fire risk and comply with the requirements of NFPA 20.

The pumps shall be of the horizontal axis centrifugal type with flooded suction. Details of the pump characteristics shall be submitted for approval.

- 6.44 -


The design of the diesel engine, in particular its lubricating system, shall be such that periods of long standing will not affect the starting up of the diesel engine.

The fuel supply tank shall have a capacity such that the diesel engine can be run at full load for at least [eight] hours. The outlet from the tank shall be at a height of not less than 600 mm above the inlet to the fuel injection pump on the engine.

A trickle charger system shall be provided suitable for keeping the starting battery fully charged.

In the event of fire water demand within the site the duty electric pump shall start on sensing low pressure in the main. The diesel pump shall start if the pressure remains low after a 5 second delay, or falls due to high demand.

Each pump discharge shall be fitted with a full flow recirculation line to the storage tank to facilitate pump testing. Isolating valves normally locked closed shall be fitted to these recirculation lines. Pressure relief devices shall be provided to protect the pumps under low flow conditions.

Jockey pump(s) shall be provided to maintain the fire main under pressure and to cater for minor usage/leakage.

The status of each pump shall be indicated on the master fire alarm panel.

The fire pumps shall be located within a building to give adequate protection from the environmental conditions.

6.5.3.3 Fire main

The pressurized fire main shall be designed on a ring main basis and sized to cater for the maximum water demand in accordance with NFPA 24. Valves (normally locked open) shall be fitted at appropriate points in the main to allow isolation of discrete sections of the site. All thrust blocks (if required), valve pits, vent and drain connections and corrosion protection measures are to be provided.

The capacity and layout of the main, and the position of hydrant outlets shall be submitted for approval.

Above ground piping shall be ASTM A106 seamless carbon steel or approved equivalent, galvanized and painted in red. The pipe size up to 50 mm shall have pipe schedule 80 having screwed joints and above 65 mm to be standard schedule with flanged joints. The pipe material including fittings, flanges and bolting etc. shall meet the appropriate codes requirement of ASTM and ANSI standards. The valve material shall be steel body and bronze trim and shall meet the design rating of the system.

The material for buried pipework, valves and fitting up to the above ground connection point at the valve station shall be ductile iron (ISO 2531) with mechanical joints, cement lined (AWWA C104) with external bituminous coating and polyethylene wrapped (AWWA C105). Buried valves shall be grey cast iron body complying with the requirement of MSS SP70 and ANSI B16.1.

- 6.45 -


All buried pipework shall be accommodated in trenches which are excavated and backfilled in ground level with the requirements of BSC P 312 Parts 1 and 3 and/or BSC P 99, the depth of cover over the crown of the pipe shall be not less than 900 mm.

6.5.4 Fire fighting systems

6.5.4.1 Automatic water spray deluge system

Each individual oil filled transformer and cable floor shall be provided with a separate water spray deluge protection system, all in accordance with the requirements of NFPA 15.

Deluge system for the transformers shall be operated by a pneumatic detection systems and for cable floors shall be operated electrically.

The pneumatic detection system shall derive instrument air from the GT station air distribution system. The alarm system shall be as described in Section 8.

Local manual push button release of deluge valves shall also be provided.

6.5.4.2 Automatic wet pipe sprinkler alarm system

A wet pipe sprinkler and alarm system shall be provided for the workshop and stores buildings. The sprinkler systems shall operate on the ‘Quartzoid’ bulb principle and shall detect an outbreak of fire and distribute water automatically over a predetermined area.

The installation shall be in accordance with NFPA 13 and local Fire Department (FD) regulations for sprinkler installations. Alarm valves shall be provided with a retarding chamber.

Operation of each individual sprinkler zone shall initiate an alarm after a time delay on the fire alarm system specified in Section 8. The alarm shall be initiated by a suitable flow switch type alarm valve.

6.5.4.3 Automatic foam/water spray deluge systems

The design of these systems shall be in accordance with NFPA 11 or 11A as appropriate and FD regulations and water shall be taken from the underground hydrant ring main.

i. Balanced pressure proportioning system. The fuel oil pump house shall be provided with balanced pressure proportioning system with aqueous film forming foam (AFFF), capable of a 3 per cent mixture in service water, shall be stored in the foam concentrate storage tank. The capacity of the tank(s) shall be twice the size of the calculated foam charge.

Two positive displacement foam concentrate pumps (duty and standby) with automatic regulating valves shall draw foam and inject into the water supply via proportioners.

The thermal detectors located in the fuel oil pump house shall initiate operation of the deluge valve through the fire alarm panel. Operation of the deluge valve shall

- 6.46 -


start the foam concentrate pump and open the foam concentrate motor operated isolating valve. Local manual push button station shall also be provided.

ii. Diaphragm pressure proportioning system. The diesel engine fire pump including its fuel oil day tank shall be protected by foam/water which shall be provided from a diaphragm type foam concentrate proportioning tank via an in line injector.

The water supply for automatic foam/water system for the fuel transfer pump house shall be fed from the fire main. An automatic control panel located in the gas turbine control room and a manual push-button station with complete alarm indication/annunciation to the master fire panel shall be supplied.

The size of the foam tank shall be suitably sized (1 m3 minimum). The foam concentrate shall be aqueous film forming foam (AFFF) capable of a 3 per cent mixture in service water.

The thermal detectors located in each protected area shall initiate through the firm alarm panel, the operation of the deluge valve and solenoid valve which shall open a piston operated ball valve to pressurize the bladder and eject foam through the proportioner. Local push button stations shall also be provided.

6.5.4.4 Remote/manual foam system and water spray system

The fuel oil storage tanks and bund area shall be protected with a remote manual foam system, comprising foam injection system, bund pourer system, and foam monitor system (located on the fuel oil tank bund wall), and a remote/manual spray water cooling system, sized to cool a full tank.

All systems shall comply with the requirements of NFPA 11 or 11A as appropriate and 16. The foam systems shall be supplied from the foam station comprising foam concentrate tanks, foam concentrate pumps, motor operated valve and proportioning equipment. The fire water supply shall be obtained from the underground ring main.

The oil tank foam injection, bund pourer, foam monitor and cooling water spray systems shall be controlled remotely from the foam station. Operation of the deluge valve shall automatically start the foam concentrate pump and open the foam concentrate isolating valve. Local manual release push button station shall also be provided.

6.5.4.5 Tank foam injection system

The foam concentrate shall be fluoroprotein foam capable of a 3 per cent mixture in desalinated water.

One foam station shall be provided for the injection of foam into the fuel oil tanks.

The foam station shall comprise one concentrate storage tank, two positive displacement concentrate delivery pumps (duty and standby), one balance pressure proportioner and all associated pipe work, motor operated valves and deluge valves.

- 6.47 -


The design and capacity of foam pumps and chambers shall be based on foam concentrate injection rate calculated in accordance with the codes.

The foam concentrate storage tank shall be sized to hold two times the calculated foam charge to protect the fuel oil tank.

Each foam chamber mounted on the fuel oil tank shall have a rupture disc assembly provided on the foam discharge outlet, to ensure that the foam system is not contaminated by oil should an overflow occur.

6.5.4.6 Tank farm bund area foam pourers

The oil tank bund area shall be provided with foam pourers, equally spaced along the bund walls of each oil tank bund area which shall be capable of covering with foam/water the entire bund area (including the oil tank) and shall be supplied with foam water from the main pipe work ring located outside the bund.

The details of the system shall be as described for the Tank Foam Injection system.

6.5.4.7 Foam monitors system

Motor operated oscillating type foam monitors complete with pipe work and valves shall be provided and placed on the bund walls. At least three monitors shall cover the tank and its bund area. Monitors shall be capable of operating at the fire system pressure and reaching the top of oil tank from any direction.

Monitors shall have horizontal and vertical movement in any combination thereof to give a complete arc of operation over the bund area with locking facilities to allow manual operation from any position. Monitors shall be of stainless steel construction and be provided with motor operated valves.

Access platforms and ladders shall be provided as necessary to facilitate operation and maintenance of all monitors, valves and equipment.

One foam station shall provide the bund pourers and foam monitors located on the tank bund wall. Each system shall be fitted with motorized isolating valve.

The foam concentrate storage tanks for foam pourers and monitors shall be sized to hold two times the calculated foam charge to protect one gas oil tank.

6.5.4.8 Spray water cooling system for the fuel oil tanks

The fuel oil storage tanks shall be protected by a remote/manual controlled spray water cooling system.

The system shall be supplied with water from the underground site hydrant water supply system.

The design and construction of the cooling system shall comply with the requirements of NFPA 15. Run off spray water shall not be taken into account in the design of the cooling system.

- 6.48 -


The system provided for the tank shall be divided equally into four hydraulically balanced quadrant systems, the operation of any one quadrant or combination of quadrants being individually controlled automatically and also from local manual release push button stations.

Each tank quadrant shall be provided with headers individually piped to a motorized control valve position suitably located outside the bund wall.

A number of frangible bulb temperature detectors shall be provided on the external periphery of the tank shell adjacent to the tank roof to activate the cooling water spray system and to raise alarm on the main fire alarm panel located in the control room. Each control valve shall be provided with all fixtures necessary for test, and operation, and shall include manual override facility for emergency manual operation. Pressure switches shall be provided for each deluge valve to provide ‘system activated’ signal to the fire alarm panel located in the Control Room.

6.5.4.9 Standpipe and hose cradle/reel cabinet system

Each building shall be provided with a standpipe system complying with NFPA 14 and designed to give Class [III] service.

The Contractor shall provide fire hose reels and hose cradles in each building.

Fire hose reel cabinets shall be equipped with a 30 metre length of 25 mm diameter double braded rubber, non collapsible hose mounted on reel drum which shall be of the swinging arm type. The hose reel connected to the water supply shall be supplied with 25 mm NB isolating ball valve and 25 mm NB pressure reducing valve and adjustable spray/jet nozzle.

Hose cradles shall consist of a 30 metre length of 40 mm lined, collapsible, synthetic hose mounted on a hose rack which shall be of the swinging arm type.

Both hose reels and hose cradles shall be equipped with quick coupling BS 336 type of gun metal with adjustable jet/spray nozzles.

A single 65 mm automatic pressure regulating valve with female instantaneous coupling connection shall be provided in each hose reel/hose rack cabinet, connected separately to the water supply inside the cabinet and available for the connection of Fire Brigade hoses even when the hose reel/hose rack is in use.

The hose reel/hose rack cabinet shall be made from galvanized steel with double glass door clearly labelled “FIRE” in Arabic and English and painted red with white lettering to an approved procedure. Each hose reel/hose rack cabinet shall also be supplied with one (1) unit of 9-10 kg dry power fire extinguisher for class ABC fires.

6.5.4.10 Site fire hydrant system

6.5.4.10.1 Fire hydrants

The arrangement of the site fire hydrant system shall comply with the requirements of NFPA 24 and shall generally comprise a buried sectionalized ring main, distribution pipe work complete with post indicator valves, isolating valves wash-out valves and valve pits. The distribution

- 6.49 -


network shall provide supply of water to each standpipe system, automatic spray foam and water deluge system, fire hydrants positioned around the power station site and the main oil tank area fire protection systems.

All fire hydrants shall be installed at a spacing not greater than 60 m and shall comply with FD requirements. Fire hydrants shall be constructed from cast iron (150 mm) with two 65 mm globe valve (BS 336 or equivalent) couplings, cap, chain and a 100 mm connection for fire engine pump suction. Each fire hydrant shall be provided with an auxiliary valve with curb box. Valves shall be 175 lb cast iron, bronze trimmed, 150 mm non-rising stem gate valve with flanged joint. Curb box shall be cast iron, 130 mm diameter with box extension piece stainless steel valve stem extension with square nut and stainless steel covers. Curb box assembly shall be cast in concrete at grade and depth of cover shall be adjusted to the proper depth of pipe. The valve shall be key operated with an operating key provided at each outdoor hydrant cabinet.

Each fire hydrant and post indicator valve position shall be protected from damage by four vertical guard rails painted with red and white bands. Where direct buried these shall be protected by suitable sleeving and backfilled with selected material approved by the Owner/Engineer.

Post indicator valves shall be 175 lb butterfly type and provided at all branch lines and for sectionalizing portions of the water network and shall meet UL design requirements. The stem length of the post indicator valves shall match the site gradient and hydrant main invert.

6.5.4.10.2 Outdoor hose storage cabinets and equipment

The Contractor shall provide one outdoor hose storage cabinet at each hydrant location, comprising weatherproof steel cabinet complete with a break glass lock mechanism. Each cabinet, mounted on a concrete foundation shall contain, as a minimum:

a. One (1) hydrant turnkey and bar

b. One (1) 65 mm hose standpipe with instantaneous outlet connections

c. Three (3) 25 m lengths of 65 mm light synthetic fibre imperviously jacketed hose with light alloy instantaneous couplings

d. One (1) Jet/spray – on/off nozzle

e. One (1) 65 mm hose branch pipe 22 mm bore nozzle

f. One (1) Fire axe and crowbar

6.5.4.10.3 Fire hose

The fire hose shall be light and flexible besides being resistant to abrasion and damage due to contact with chemicals or oil. The hose shall comply with BS 3169 or equivalent.

The bursting pressure of the hose shall not be less than twice its working pressure.

Hose is to be 65 mm gauge and supplied in 25 m lengths with male and female instantaneous couplings compatible with local requirements/regulations.

- 6.50 -


6.5.4.10.4 Jet/spray – on/off branch pipe nozzle

These nozzles shall emit a powerful straight jet, atomized spray or a wide – spreading cone of solid water and shall include fog and shut off features.

The type of spray shall be adjusted by twist control.

Nozzles are to be manufactured in light alloy and fitted with a stainless steel valve cone and designed for maximum velocity at the minimum restriction to flow. The inlet shall be a male instantaneous coupling.

6.5.4.10.5 Standard water branch pipe

Branch pipes shall comply with BS 446 or equivalent. The inlet shall be a male instantaneous coupling. The outlet shall be 5/8” diameter to give a high power straight jet of water.

6.5.4.11 Gas extinguishing systems

Each gas turbine generator shall be supplied with an independent CO B2B system to protect the turbine enclosures.

The design of the total flood gaseous fire protection system shall comply with NFPA 12. In particular, for the GT noise enclosures the Contractor shall demonstrate by computational means; e.g. Computational Fluid Dynamics (CFD), to ensure that the enclosures provide adequate dilution ventilation to prevent potential explosion.

Sufficient gas shall be provided for each gas turbine to extinguish the worst fire likely to be experienced. The pipework and bottle location may be arranged on a zoned basis if preferred.

The system shall include fully charged CO B2B cylinders, cylinder valves, mounting brackets, automatic and manual release controls, piping and nozzles, audible and visual alarms and safety monitors. A simple means of weighing each cylinder without removing it from service shall be supplied. A hand trolley suitable for the transporting a single cylinder shall also be provided. Spare fully charged bottles amounting to 20 per cent of the total installed capacity shall be provided with this contract.

6.5.4.11.1 System operation

The COB2B discharge shall be initiated by the fire detection system refer to Section 8 for further details. Enclosure or room ventilation shutters shall close automatically and all ventilation fans shall shut down when COB2B is discharged into the enclosure. The initial discharge shall be followed by an extended discharge at reduced flow.

A loud alarm bell shall sound continuously in and on the outside of the room or enclosure before discharge to warn personnel to evacuate. The bell shall sound intermittently when a fire has been detected on one circuit only.

COB2B shall be discharged from the cylinders through the distribution pipework to the discharge nozzles within the space containing the fire.

- 6.51 -


A safety lock-off device shall be supplied at all enclosure entrances to isolate the automatic discharge. Illuminated signs at all enclosure entrances shall indicate whether the CO B2B system is in the charged, locked–off or discharged condition.

Manual release units suitably located shall provide manual override of the system. This feature shall override the automatic conditions but not the lock-off.

6.5.4.11.2 Pipework for gas extinguishing systems

All pipes shall be galvanized ASTM 106, with forged steel screwed fittings to ASTM A234. All gas pipe work shall be painted signal red.

Gas discharge nozzles shall be shall be manufactured from a corrosion and heat resistant material as approved by the Owner/Engineer.

Pipework shall be hydraulically tested to a pressure 50 per cent higher than the working pressure, and shall include a safety rupture disc on the gas manifold to burst at a pressure of 120 per cent of working pressure.

A relief valve shall be fitted to each gas manifold to vent to atmosphere any small leakage of the agent when the system is not in operation. These valves shall close immediately under pressure in the event of the fire agent system being operated.

The Contractor shall submit all operating/safety procedures for approval by the Owner/Engineer.

6.5.4.12 Fuel gas treatment (AGI) system

The AGI for the gas system shall be protected by the yard hydrants which shall be located near this area at spacings as specified.

The area shall also be provided with a fire detection system as described in section 8.

6.5.4.13 Portable extinguishers

The following types of portable fire extinguisher equipment complying with NFPA 10 shall be provided and installed at agreed locations including wall mounting, in the plant and building areas.

i. 9-10 kg capacity dry power extinguishers for use against oil fires associated with electrical equipment. The powder shall be expelled from the extinguisher by compressed COB2B gas and controlled by a pistol grip nozzle attached to the discharge hose.

ii. 9-10 kg and 6 kg capacity COB2 Bextinguishers for use against fires associated with electrical equipment. The extinguishers shall be provided with fixed discharge horn and trigger valve control and trolley where required.

iii. 9-10 litre/capacity COB2 B gas pressure operated water extinguishers for use against ordinary small fires. The discharge nozzle shall be supplied with flexible hose and the control shall be such that intermittent control is possible.

- 6.52 -


iv. 9-10 litres capacity foam extinguishers for use against small oil fires. The extinguishers shall be pressurized with COB2B gas.

The number and types of extinguisher per building are to be advised in the Tender and shall be in accordance with the recommendations given in NFPA 10 and shall be to the Owner/Engineer’s approval.

6.5.4.14 Fire detection and alarm system

The fire alarms system shall be complete in all respects and shall include the main and local fire alarm/control panels, the fire detection system, the alarm contacts for local and remote signalling, all cabling between the fire detectors and alarm contacts and the local and main fire alarm/control panels.

Refer to Section 8 for details regarding the fire and gas detection and fire alarm systems.

6.6 Instrument and service air systems

6.6.1 General

A compressed air system shall be provided to accommodate the requirements of both instrument and service air as appropriate for the complete power station. The compressed air system shall be capable of meeting all plant requirements during any operating condition, including start up, shutdown and trip.

The standby compressor shall start up automatically in case of air pressure abnormally decreasing. Moreover, a valve in the service air supply main header shall shut automatically in case of very low air pressure to ensure continuity of instrument air supply which has priority over service air supplies.

The air quality for the control air systems shall be filtered to 5 microns, with a dewpoint of –40P

°PC. The air pressure in the pipe distribution system shall be 7 barg.

The filter/dryers supplied as part of the instrument air system shall be sufficient to condition the air required by the plant whilst the second train of filter/dryers is in standby mode.

Air storage volume, compressor running periods and compressor control method are closely interdependent. The system designs shall be optimized for minimum total costs. The optimization calculations shall be submitted to the Owner/Engineer for approval.

System design and equipment shall conform to the requirements and recommendations of the appropriate Codes and Standards.

- 6.53 -


6.6.2 Scope of work

Main equipment shall include, but not be limited to the following:

a. two (2) 100 per cent capacity air compressors, designed to operate on a duty/standby basis, each complete with suction air sand separator and filter/silencer, intercooler and aftercooler with moisture separators;

b. one (1) general service air receiver of sufficient capacity to facilitate safe shut-down in the case of emergency, with all other provisions considered;

c. two (2) 100 per cent capacity instrument air receivers of sufficient capacity to facilitate safe shut-down in the case of emergency, with all other provisions considered;

d. two (2) 100 per cent instrument air filters;

e. two (2) 100 per cent instrument air dryers;

f. instrument air distribution system, including instruments, valves, piping and supports;

g. Service air distribution system, including instruments, valves, air-line couplings, piping and supports. A ‘priority’ valve shall be included, operable from the CCR, to shut off the supply from the air compressors to the service air system in the event of low pressure in the instrument air header.

6.6.2.1 Sand separators

Dust and sandstorms may occasionally occur at site. Occurrence of dust and sandstorms must not compromise compressor operation. One cyclone or equivalent inertial type sand separator per compressor shall be installed.

A special motor driven valve for releasing the dust out of the collector and a collecting drum with a minimum volume of 1 mP

3P shall be furnished with each dust collector.

Indication of the dust level inside the sand separator and pressure differential indication shall be supplied.

The sand separators and the suction duct shall be installed in such a way that neither dust from ground nor rain water can be drawn into the separator.

6.6.2.2 Suction air filters/silencers

The suction air filters on each compressor suction side shall retain all dust and sand not collected in the sand separator. They shall be designed for low pressure loss and the compressor design shall be on the basis of the filter being obstructed up to the maximum allowable differential pressure.

- 6.54 -


The suction air filters shall be of the single element dry type. Filter screens shall be quickly changeable or cleanable. Means to indicate when cleaning or replacement is needed shall be provided.

The silencers shall be the manufacturer’s standard, specially designed to dampen the low frequency compressor intake noise.

The suction air filter/silencers shall be designed for low pressure loss. The compressor design shall be based on the filter being 50 per cent obstructed.

6.6.2.3 Air compressors

The compressors shall be of the electrical, direct driven, multi-stage rotary type. Oil lubrication of the instrument compressor parts in contact with compressed air is not acceptable.

Each compressor shall include a motor, coupling, base plate, lubrication system, water cooling system and all appurtenances.

One (1) set of special maintenance tools for compressor overhauling shall be provided.

Each compressor shall have the following design features:

a. The period between two inspections for maintenance shall be not less than 10 000 operating hours.

b. The compressors shall be of heavy duty construction and designed for continuous and intermittent operation at full and low capacity.

c. The compressors and associated equipment shall be mounted on a fabricated skid base. All piping leaving the skids shall have flexible connections to approval and the piping shall be adequately supported to prevent transmission of vibration and noise.

d. The compressors shall be of two or three stage configuration water cooled type with intercoolers.

e. The impeller shall be manufactured from stainless steel.

f. Bearings shall be lubricated with oil. A lubrication system with a shaft driven pump and an electrically driven pre-lubrication pump shall be supplied.

g. Modulating control shall apply over the full operating range.

h. The noise level of the compressors shall not exceed 85 dB(A) at 1 m from the source

- 6.55 -


6.6.2.4 Air compressor control

Each compressor shall have automatic start and stop controls which shall include an unloading device to unload the compressor when it is stopped and maintain that condition until the motor is again up to speed. The compressor shall also be provided with controls which shall unload the compressor when the pressure in the receiver reaches a predetermined level and load the compressor when that pressure drops below a predetermined level without stopping the motor. The pressure controls shall be adjustable over a wide range and shall operate with a maximum pressure change of 0.2 bar.

6.6.2.5 After-coolers

One pipeline type after-cooler per compressor with cyclone type water separators shall be provided. The approach temperature, i.e. difference between outlet air temperature and inlet water temperature shall be 6°C for the after-coolers.

Cooling water will be inhibited demineralized water of the closed circuit cooling water system.

Easy access for inspection and cleaning shall be provided. Drains shall be provided. Each cooler shall be equipped with a relief valve.

The after-coolers shall be suitably mounted so as to be accessible for maintenance and inspection.

Fouling factors shall be as recommended by TEMA

6.6.2.6 Air receivers

The air receivers shall keep an ample amount of air available during short time air consumption peaks to reduce the frequency of compressor cycling whilst maintaining air pressure supplies at or above an acceptable minimum level.

Each instrument air receiver will be designed for a storage capacity, without any additional air make-up supply, which is the larger of:

a. Ten minutes storage on normal plant operation or,

b. The capacity to run down the generating units and station service auxiliaries from full load operating condition to non-operation condition.

Each receiver shall have a pressure gauge and code stamped relief valve(s). Design temperature shall be compressor discharge temperature without after-cooling.

Each receiver shall be furnished with one (1) snap-action type moisture trap. Each trap shall be provided with a bypass valve.

Easy access to the drain valve shall be provided. The bottom of the vessel shall be at least 300 mm above the floor.

- 6.56 -


Each receiver shall conform to the appropriate Codes and Standards and shall be suitable for the site ambient condition specified in Schedule A.

6.6.2.7 Instrument air dryers

Two 100 per cent capacity air dryers shall be provided to dry the instrument air. The dryers shall be of the dual tower, regenerating desiccant type each capable of meeting the requirements of the unit instrument air demand and of removing moisture from the instrument air over the range of design ambient conditions specified in Schedule A for the following design instrument air dewpoint:

Outlet dewpoint -40°C

Visual indication of dewpoint shall be given by means of colour change indicators.

The dryers shall be packaged self-supporting units, shipped completely piped and wired. The dryer shall have a control cabinet and multiport valves for automatic transfer of air between towers.

Each drying vessel shall have a drying capacity equal to ten hours at the rated output and regeneration, including vessel cooling, shall not be more than 6 hours.

Moisture shall be removed during regeneration by internal electric heaters and/or purge air and expelled from the vessels to atmosphere by a stream of purge air. The towers shall be fully insulated.

In the event that a dryer is supplied without heaters the compressor capacities shall be adjusted for the increased purge air flow. No provision shall be made for by-passing the air dryers.

The pressure drop at full load conditions and across the complete dryer/filter package shall not exceed 0.5 bar when clean.

6.6.2.8 Pre and after-filters

Each instrument air dryer shall be provided with a pre-filter and after-filter. The pre-filter shall protect the desiccant of the dryer from contaminants such a liquid (water), pipe scale and dirt; while the after-filter shall prevent desiccant fines of the dryer from entering the instrument air supply headers.

The filters shall be compatible with the dryers in all respects. The water mist removal capacity of the pre-filter shall be not less than 99 per cent and the after-filter shall removal all particles greater than 1.0 micron in size. The pre-filters shall have coalescing elements which will concentrate water mist to bulk liquid for removal by traps. The filters shall have sufficient area so that replacement of cleaning shall be required only at reasonable intervals. Each filter shall be provided with a differential pressure gauge.

- 6.57 -


6.6.2.9 Drains

The compressed air systems shall have drains on all low points. Snap-action type traps with inlet strainers shall be provided. The minimum size shall be 20 mm.

Drains from all low points in headers, water separators and air receivers shall empty into a waste funnel connections.

6.7 Painting and protection against corrosion

All material and equipment shall be effectively protected against corrosion during transit and while being stored at site. All materials and equipment shall be protected by the application of anti-corrosion agents in a mineral-oil base.

6.7.1 Painting

All surfaces to be protected shall be coated in accordance with the requirements of ISO12944: 1998. Preparation grade for surfaces shall be a minimum of Sa 2½.

All exterior surfaces, including buried and aboveground pipe work, shall be of high durability (>15 years) and appropriate to a C5-I (very high industry) or C5-M (very high marine) environment as appropriate. Interior surfaces shall be of be of high durability (>15 years) and appropriate to a C4 environment.

High temperature and intumescent coatings shall be in accordance with manufacturers’ guidelines.

The method of application shall be to the approval of the Engineer and shall be taken to ensure mechanical and electrical compatibility with the factory applied coating and the cathodic protection system.

The Contractor shall provide a full paint and coatings schedule to demonstrate the adequacy of the provision. The Contractor shall submit to the Engineer six (6) sample chips (100 × 150 mm size) of each colour and finish on the type of surface specified. Colours shall be indicated on the paint and coatings schedule.

6.7.2 Galvanising

Where employed, galvanising of surfaces shall be in accordance with the requirements of BS EN ISO 1461 or ASTM A123/A123M-01a. Bolt fixings shall be galvanised in accordance with the requirements of ASTM A153/A153M-01a.

Preparation grade for surfaces shall be Sa 2½.

Where the galvanised surface is rendered discontinuous for any reason, the un-galvanised surface shall be thoroughly cleaned to bright metal and painted to the requirements of BS EN ISO 1461 or ASTM A123/A123M-01a.

- 6.58 -


6.8 Cathodic protection

A complete and fully automatic cathodic protection system shall be provided in accordance with BS 7361: 1991. An impressed current system shall be preferred and shall include but not be limited to: distributed anode ground beds, transformer rectifiers, distribution panels, wiring and monitoring. Where appropriate, smaller structures may be protected by sacrificial anodes.

The cathodic protection system shall be brought into operation immediately upon completion of construction of the plant to be protected. The Contractor shall undertake all necessary precautions to ensure that the current density is appropriate to guarantee protection. Particular note shall be taken of the presence of other buried services in the area of the protected plant.

The Cathodic protection system shall have a design life of 25 years.

The Contractor shall provide a schedule detailing all vessels, tanks, structures and submerged/buried pipelines to be protected by a cathodic system to demonstrate the adequacy of the provision.

6.9 Cranes and lifting equipment

6.9.1 General

Sufficient cranes and lifting equipment shall be provided throughout the power station for the maintenance of all equipment.

A list of all cranes and lifting equipment shall be provided in the Tender.

6.9.2 Electrical overhead travelling cranes

A pendant operated overhead travelling crane shall be provided in the [Workshop], and in other plant buildings if required for maintenance of the plant.

The crane shall be designed and constructed in accordance with the requirements of BS 466 and BS 2573, and shall be complete in all respects for safe and efficient operation.

The capacity of the hoist shall be sufficient for the heaviest expected maintenance lift in these areas but in no case less than five tonne capacity.

The bridge or gantry, trolley and hoist movements shall be controlled by suitable reversible controllers. The bridge trolley and hoist control schemes shall permit variable speeds in both directions of travel. Limit switches shall be provided at end limits of bridge, trolley and hoist travel.

6.9.3 Mobile cranes

Self-propelled diesel engine driven mobile telescopic cranes shall be provided where required. The capacity and reach of the hoist shall be sufficient for all maintenance lifts associated with the Generating Plant, and all other ancillary plant located outdoors.

- 6.59 -


The crane shall be complete with all necessary appurtenances to ensure its safe and efficient operation.

6.9.4 Runway beams and lifting facilities

All heavy parts of the plant supplied under the Contract shall be provided with arrangements for lifting, slinging and handling during erection and overhaul. All parts normally lifted during periods of maintenance and weighing one tonne or over shall be appropriately marked with their weight.

Runway beams shall be provided to facilitate handling of the various parts of the plant which require to be removed for cleaning and overhaul. The beams shall be supplied with trolleys for the attachment of blocks and lifting tackle and a range of suitable blocks and tackle shall be supplied. The runway beams shall comply with the requirements of BS 2853 and shall be tested after erection. The Contractor shall be responsible for the provision of the appropriate test certificates which must be in accordance with Appendix C of BS 2853.

All necessary lifting beams and slings shall be provided

6.9.5 Testing

All cranes and lifting equipment shall be proof load tested, mechanically, electrically and operationally. The Test results shall be recorded on certificates, copies of which shall be submitted to the Engineer.

The safe working load shall be clearly marked on all cranes and lifting equipment.

6.9.6 Use of cranes for initial erection

All cranes used during the initial erection of the plant shall be refurbished to their "as new" condition before they are taken over.

6.10 Workshop, stores and equipment

6.10.1 General

A complete workshop shall be provided to enable general maintenance work, of the whole plant, to be carried out. The workshop shall be provided with an overhead travelling crane, pendant operated, of suitable capacity for the largest maintenance load. This workshop is not intended for major gas turbine overhaul work

The Contractor shall propose the equipment he considers fulfils the philosophy outlined above and shall include for the supply and installation of all fixed equipment within the workshop building. All equipment will be to the approval of the engineer.

A stores building shall be provided to provide suitable storage conditions for plant spare parts, consumables etc.

- 6.60 -


6.10.2 Workshop compressed air system

It is intended that the station instrument and general service air systems be piped into the workshop building. The Contractor may however propose a separate system for the workshop (to the same standard specified in Section 6.6) if the location of the workshop poses any difficulties in routing of the station compressed air supplies into the building.

6.10.3 Stores equipment

The stores shall be fully fitted out for operational use.

The Contractor may offer his own proposals but these shall include but not be limited to:

a. Steel racking for storage of materials and components.

b. Steel racking and plastic bin system for storage of smaller parts.

c. Propane powered stacking fork lift truck with capacity to reach highest storage racking.

6.11 General plant requirements

The following requirements shall apply to all plant and equipment to be supplied under this Contract, unless specified otherwise in sections relating to specific items of equipment.

For general requirements regarding inspection and testing, refer to Volume 2, Schedule G of this Specification.

6.11.1 Plant referencing

6.11.1.1 Plant referencing system

The Contractor shall apply a plant coding/referencing system eg KKS (Kraftwerk Kennzeichen System) or other similarly internationally recognized numbering system for referencing of power equipment and systems.

The Contractor and his subcontractors shall use the plant referencing system for numbering of equipment, piping, valves, cable, instrumentation and spares. Reference numbers listed on identification nameplates or tags shall be as per the approved plant referencing system.

6.11.1.2 Plant numbering/nomenclature guidelines

In addition to the plant referencing system, plant and equipment items shall be identified by a nomenclature system; the following guidelines shall be used by all parties in determining the plant numbering/nomenclature:

a. the reference should be logical and simple

b. each name should be unique

- 6.61 -


c. there should be a differentiation between unit and non-unit names

d. the names should be as short as possible

e. the name should start with the major and proceed to the minor (in the case of feed heaters numbering shall be consecutive from the lowest pressure to the highest)

f. the same name should consistently appear on all drawings, schedules and labels.

References shall follow a logical sequence based on layout or history and in any particular installation, a set of similar duty drives where any number of units may run, shall be suffixed 1, 2, 3 4 etc. whereas alternative drives for the same duty, where only one unit may run (ie duty/standby), shall be suffixed A, B, C etc.

The Contractor shall also prepare a comprehensive Plant or Equipment Identification Schedule(s) using the plant reference system, which shall be updated and issued to the Engineer every 6 months for the duration of the Contract. The Schedules shall include the Purchaser’s numbering system and the respective flow sheet or Diagram Identification Numbers.

After final painting, all main plant items shall be identified by the reference characters. Such references to be affixed in a prominent position on the plant body with characters not less than 100 mm high or as otherwise specified.

Characters shall be bold capital letters and/or Arabic numerals. The abbreviation ‘No.’ shall not be used

6.11.2 Nameplates and labels

Instruction plates, nameplates and labels shall be provided for all items of the plant giving particulars of duty, size, serial number and full information for identification and operation.

Nameplates shall be 3 mm thick laminated white, black, white traffolyte with lettering of a minimum height of 4 mm. Warning labels and emergency equipment shall have red lettering in place of the black. Warning and safety notices shall be in the English and Arabic languages.

Labels shall be of sufficient size to carry a full description of the plant item and a unique item identification alpha-numeric. Abbreviations in the plant description shall only be used with prior approval of the Owner/Engineer.

Valve labels shall be circular and fitted in the centre of the valve handwheel. All other labels shall be square or rectangular and shall be fitted by 3 mm stainless steel self-tapping screws or stainless steel banding as appropriate for the location. Labels shall be fitted such that they are not readily lost or broken during routine operation and maintenance.

Any labels damaged or defaced during installation or plant start-up shall be replaced by the contractor prior to plant acceptance by the Owner/Engineer.

- 6.62 -


6.11.2.1 Pipe service identification

A colour banding scheme shall be used to identify pipework. The identification requirements and colours employed shall be in accordance with the requirements of BS 1710 and BS 4800 respectively.

Colour bands shall be painted on each side of all valves and equipments on the piping systems. The use of adhesive-backed colour bands is not permitted.

Valve labels shall be circular and fitted under the handwheel captive nut. For check valves and small valves the Contractor may provide rectangular labels fitted to the valve or secured close by the valve.

The inscription or “name” on each valve label shall summarize the duty of the valve, and the number shown on each valve label shall be the number in the unified plant valve numbering scheme.

Where the direction of flow through a valve or other device is an important requirement for correct functioning, the body of the valve or device shall be legibly marked with a cast on or a properly secured arrow, showing the direction of flow.

Pipework shall be provided with plentiful large painted arrows and/or other secure and durable arrow markings to allow the flows of fluids around the plant to be readily understood.

6.11.3 Plant vibration

Rotating Plant shall be designed and constructed to operate throughout its operating range without vibration insofar as the nature of the works will permit. In the case of rotating plant, vibration shall be reduced to the minimum, which can be achieved by good design, careful balancing and correct installation and alignment, as follows:

a. Rotating elements shall be balanced in accordance with the relevant grade of ISO 1940-1 as applicable.

b. The vibration levels for the machinery covered by this Specification shall comply with the appropriate parts of ISO 10816 and ISO 7919 standards.

c. Provision shall be made for the reduction of vibration transmitted to covers, cladding, platforms and structures that are liable to vibrate.

Refer to the relevant specification sections for vibration requirements for specific equipment, and to Section 8, Control and Instrumentation for details of vibration measurements.

6.11.4 Sunshades

Outdoor plant shall be rated and constructed so that its performance, operation, reliability, maintenance, or life shall meet the specified design and operating conditions.

- 6.63 -


Where personnel have to be in attendance frequently or maintenance has to be regularly carried out, permanent minimum weather protection or sunshades shall be provided.

Facilities such as lighting, lifting beams and rainwater drainage shall be provided wherever necessary to the approval of the Engineer as an integral part of the sunshade structure.

6.11.5 Special tools and tackle for maintenance

The Contractor shall supply a complete set of any special tools and other equipment necessary for the dismantling, re-erection and adjustment of the plant.

This shall include any special lift jigs, frames and stands necessary to remove and support the major items of plant.

The tools provided shall be in new condition, adequately labelled as to their use and contained in stout and suitable padlocked boxes. The Owner/Engineer’s instructions as to who shall be the recipient of the tools shall be sought before delivery is made.

Any special slings required shall be provided and clearly marked by embossed labels to show safe working loads. Test certificates shall be provided where applicable.

6.11.6 Locks and keys for mechanical plant

Locks and keys for mechanical plant shall be of an approved dead latch type, or padlocks as appropriate. Three keys shall be supplied for each lock. Keys shall be unique to each lock.

Where a set of locks is provided under any particular section of the Plant, a group master key shall be supplied in addition.

All locks and padlocks shall be of brass and where they are fitted to switchboards or similar cubicles shall have the visible parts chromium plated.

Where a group of locks is supplied under any part of the Contract, a rack or cabinet of approved design shall be supplied for the accommodation of all padlocks and/or keys while not in use. The padlocks and keys shall be engraved with an agreed identifying code or inscription and this shall be repeated on the racks or cabinets on engraved labels.

6.11.7 General mechanical requirements

6.11.7.1 General

The Contractor shall be responsible for the detailed design and engineering of the plant and systems. The requirements specified herein shall form the minimum basis for the design and scope of work and working practices, manufacturing, testing and erection.

Selection of materials, components, methods of construction and erection shall be made with due consideration to the requirements and capabilities of the equipment served, as well as the reaction and thermal, chemical, or other effects of the medium being handled by each system or component. Corrosion allowance for piping shall be 1.5mm unless otherwise specified. The

- 6.64 -


equipment, materials and services provided by the Contractor shall be consistent with the need to develop a safe, dependable, and adequate installation. The Contractor shall ensure that no individual element or system will set a limit on the station capability, or will disturb its architectural appearance when completed.

6.11.7.2 Piping systems

6.11.7.2.1 General requirements

The design, manufacture, installation and testing of piping systems shall be in accordance with approved codes, such as BS/ISO/ANSI or equivalent internationally recognised codes.

During the design engineering, the Contractor shall supply to the Engineer schedules of the piping systems provided under this Contract. The schedules shall state, for each piping system, the design code, pressures and temperatures, the piping materials and contents, the valve type and materials, corrosion allowances, piping supports and insulation proposals and any other data relevant to the mechanical design of the piping system or part thereof.

Unless otherwise specified or approved, all pipes shall be of seamless drawn carbon or alloy steel.

In any one system or piping service all piping and fittings shall be of the same material or similar analysis.

All piping shall be routed to provide a neat and economical layout so that full access is provided for the operation and maintenance of equipment and that removal or replacement of equipment can be achieved with the minimum dismantling of piping.

The number of joints shall be kept to a minimum necessary. Tees and bends shall be to standard dimensions. Bends shall be of the pulled type or forged. Hot bending with packing may be used for larger sizes according to facilities available, but hot bends in alloy or stainless steels shall be subject to approval of the Engineer. No crimping or flattening of the bend will be accepted. Where employed for low pressure piping, gusset or mitre bends shall be designed to the relevant piping code.

Where piping is subject to mechanical cleaning (pigging) the bend radius shall be not less than 5 pipe diameters.

6.11.7.2.2 Terminal connections

All welding and flange connections shall be carried out unless otherwise specified, by and under the full responsibility of the Contractor.

For flange connections the Contractor shall also supply, where appropriate, the companion flange and the necessary jointing material. In case of weld connections the Contractor shall, where appropriate, make good the final joint, pipe protection and reinstatement.

- 6.65 -


Termination points shall be as indicated in the Tender drawing. The Contractor shall be responsible for finalizing the connection requirements at each termination point and shall agree the precise location and scheduling of interconnection work with Owner/Engineer to minimise disruption to existing plant and services.

6.11.7.2.3 Pipe sizing

The following maximum fluid velocities are guidelines to be used for the purpose of pipe sizing during the preparation of tenders. The final selection of fluid velocities and pipe sizing after contract award shall be the responsibility of the Contractor, such selection being subject to review and approval by the Owner/Engineer.

Service Maximum velocity

Water : discharge 3.0 m/sec

: suction 1.8 m/sec

Fuel oil : discharge 2.0 m/sec

: suction 1.0 m/sec

Fuel gas : 30 m/sec

Service air 15 m/sec

Instrument air 10 m/sec Pipes of diameter less than 25 NB may only be used for control/impulse and chemical

dosing.

The rating of discharge piping of pumps shall be a minimum of 1.05 times of pump maximum outlet pressure or pump shut-off pressure, whichever is the largest.

6.11.7.2.4 Pipe materials

Unless stated otherwise in this specification, the minimum requirements for piping material shall be as follows:

Service Material

Fuel oil API 5L – Gr B

Fuel gas API 5L – Gr X52

Demineralized water Rubber lined carbon steel/stainless steel (316L)

Service water - below ground - aboveground

Ductile iron (cement lined/externally coated and wrapped) A 106 or A53GrB flanged (screwed small bore)

Potable water - belowground - aboveground

Ductile iron (cement lined/externally coated and wrapped) Hard copper

Fire fighting water - belowground aboveground

Ductile iron (cement lined/externally coated and wrapped) A106 GrB (Galvanised – flanged)

Chilled water A106 GrB

- 6.66 -


Instrument air A53 GrB (galvanized – screwed)/stainless steel 304

Service air A53 Gr B (Galvanized - screwed) The Contractor may propose alternative materials to those specified above. In each case,

the Contractor shall demonstrate to the satisfaction of the Engineer that the proposed alternative materials are equivalent to or superior to those specified.

6.11.8 Erection of pipework

All pipes before being butt welded, or in the case of pipes fitted with flanged joints before the flanges are welded and/or bolted together, shall be hung on their respective supports and lined up so that the joints are parallel. In making joints no springing of pipes into position will be allowed except where approved for the purpose of relieving strains due to expansion. The Contractor shall submit for approval details of his proposed arrangements for such springing of the pipes, illustrating the method of maintaining coaxiality of the pipes and of maintaining the necessary forces and moments during the welding and heat treatment operations.

6.11.9 Pipe supports and expansion

All brackets, stays, frames, fixed or roller supports and hangers of approved design necessary for carrying and steadying the pipes, valves and fittings shall be provided. All steelwork which may be necessary for the attachment of pipe supports or anchors shall be provided by the Contractor. Supports shall not be welded to the bottom flange of beams.

Pipes and fittings shall be so supported that the pipes may expand and contract freely. Supports shall be so designed that on the removal of one support the load is safely re-distributed over the remainder and arranged that any pipe, valve or fitting can be withdrawn without disturbing the remainder of the pipework system. All supports for high pressure steam and other pipes subject to high temperature conditions shall be of the same material as the pipe and fitted direct to the pipe itself.

Particular attention shall be given to the supporting of polyethylene piping and if necessary all heavy valves and fittings shall be independently supported. The spacing of supports for polyethylene piping shall be to approval and where dictated by the operating temperature the supports shall be continuous. Polyethylene piping shall not be erected in close proximity to hot surfaces.

Pipe systems shall be properly anchored at approved points and all expansion and contraction shall be taken up by bends or loops except that in the case of low pressure piping systems, approved expansion joints may be used.

6.11.10 Low pressure pipework

6.11.10.1 General

All low pressure (less than 25 bar g) pipe work shall conform to the general pipe work specification, wherever applicable and shall meet the following particular requirements except where pipe materials are already specified for each application.

- 6.67 -


Unless otherwise specified, all piping for low pressure water, drains, air, gas and oil services shall be of heavy duty seamless pipe to ASME/ANSI carbon steel.

All pipe work shall be suitable for such working pressures as required by the design of the plant, but nowhere less than 10 bar.

Facings or tapped bosses for the mounting of instruments as found necessary during the construction works shall be provided on the pipe work.

Medium or high density polyethylene piping may be used for underground potable water service providing the pressure and temperature ratings are compatible with the system design requirements. Jointing shall be to approval however in no case shall screwed joints be accepted for polyethylene piping. All bends shall be performed using the standard range of preformed fittings. The use of such material for potable water applications shall be subject to approval prior to use.

6.11.10.2 Fuel piping

All headers, branches and pipelines shall be sized taking into account the flow rate required to sustain simultaneous peak load operation of all gas turbine units when fired on fuel with the lowest specified calorific value.

Joints for fuel piping shall be butt welded, flanged connections shall only be allowed for pumps/strainers, control and relief valves and flow meters and other locations where it is essential. Fuel gas and gas oil piping shall be carbon steel to the relevant ASME/ANSI codes.

6.11.10.3 Lubricating oil pipework

Supporting systems must prevent vibration under all possible operating conditions. Welding shall be used as far as practicable. Where screw joints are used they will be properly secured against loosening by vibration.

Arrangement and support of all oil piping shall be such that detrimental vibrations do not occur under any possible operating condition.

Thermowells shall be welded to the pipes.

Piping shall be prefabricated in the factory and be dispatched fully acid-pickled and properly sealed and protected against corrosion. The Contractor may consider stainless steel in order to facilitate a fast track programme for oil flushing.

Within the gas turbine block, for ease of pipe fitting on Site, the fitting lengths installed in the various pipe runs shall be flanged to avoid welding on prefabricated pipes. The fitting lengths shall be cleaned and acid-pickled before installation.

6.11.10.4 Compressed air pipework

All compressed air pipe work shall be hot dip galvanized throughout conforming to BS EN ISO 1461 or equivalent standard. All galvanizing shall wherever possible be carried out after

- 6.68 -


fabrication work. Where pipes are cut or screwed after galvanizing this shall be made good. All galvanized pipe connections shall be threaded, or flanged, but not welded.

All branches shall be taken from the top of the mains. Each branch pipe to compressed air points shall terminate in a standard fitting.

The mains shall have a suitable slope to allow drainage and shall be fitted with automatic drain traps and the necessary isolating and bypass valves. Instrument - and control air connections from the mains to the consumers shall be made of 316L stainless steel pipes with screw fitting joints. Similarly 316L stainless steel piping shall be utilized between the air compressors and the dryers.

6.11.10.5 Drain and vent pipe work

All necessary drain and air release valves and associated pipe work shall be provided as required by the physical arrangement of the piping and shall be led away over drain funnels in an approved manner. The nominal bore of the drain or air release pipes shall not be smaller than 25 mm.

6.11.10.6 Ductile iron pipework and fittings

Ductile iron cement lined pipes and fittings, as used in potable water distribution for underground piping systems, shall comply with the requirements of ISO specifications as regards methods of manufacturing, tolerances, marking and testing. The pipes, fittings and rubber rings used for jointing shall be suitable to withstand the operating requirements and ambient weather conditions. Pipes shall be supplied in standard lengths with mechanical joints wherever possible. The specification, dimensions and thicknesses of pipes and fittings, unless otherwise stated, shall comply with the requirements of the latest edition of ISO 2531 standard.

Where ductile iron pipes and fittings are supplied with sockets for push-on joints, mechanical or rubber ring, thrust blocks shall be provided at all changes in direction etc unless the Contractor can justify otherwise.

Glands shall be of ductile cast iron of the same quality as the fittings and tested for tensile strength and hardness. Glands shall be marked with the manufacturer’s name, date of manufacture and nominal diameter and coated with a 4 mm thick bituminous compound.

For easy maintenance all valves and interconnection sections shall be flanged.

All fittings with flanged ends of 600 mm diameter and smaller shall be in accordance with ANSI B16.1/B16.5. Bolts and nuts shall be of galvanized mild steel and gaskets shall be of rubber and reinforced, of thickness not less than 3 mm and shall conform to AWWA C11.

6.11.10.7 Valves

6.11.10.7.1 General

All valves shall be manufactured from first quality material, have superior designed parts, dust-tight construction, and have easily maintained lubricating systems. All valve parts shall be arranged for ease of accessibility in the installed position.

- 6.69 -


The design and manufacture of all valves shall be to the approval of the Owner/Engineer. Valve information shall be detailed in the appropriate technical data sheets to be included in the Tender and shall include operating pressure range, nominal set pressure, and type of actuator.

Valves shall be suitable for the service intended, with materials suitable for the medium to be handled, and certified as acceptable by relevant codes and standards for the service and duty intended. For the gas turbine package, the Contractor’s Standard will be considered.

Manually operated valves with a nominal size greater than 250 mm, which have to be opened or closed very quickly or with minimum manual effort shall be provided with a suitable gear system.

All isolating valves which are required to open or close during normal operation of the plant, including start up and shut down shall be equipped with an installed actuator and shall be capable of being locked in both the open and closed positions. The Contractor shall provide the necessary devices and locks.

The internal diameter of all valves at the ends adjacent to the pipes shall be the same as the internal diameter of the pipes to which they are jointed unless otherwise approved by the Owner/Engineer. Valves shall have butt weld or flanged ends in accordance with the piping system requirements. Butterfly valves shall only be used when specifically approved.

Cast iron, bronze or brass valves are not permitted for any piping system except as specifically mentioned herein.

All valves and pipe fittings material shall be as indicated in ASTM code or approved equivalent.

All valves of sizes up to and including NB 65 shall be globe valve type and shall have an ANSI Class 600 rating for all services. Where globe or angle style valves are used they shall be installed with the normal flow entering beneath the disc.

Check valves shall be of the inner-shaft type and no stuffing box or counterweight type check valve shall be permitted. Check valves shall be non-slamming type. Examination and/or replacement of parts shall be possible without removing the check valve from the line. Check valves in vertical pipe runs should be avoided, however, where necessary these shall be provided with by passes and drain valves.

Cast or steel-forged bodies shall be used for high-pressure valves >25 bar) with a nominal bore larger than NB 65, and for smaller bore, steel forged bodies shall be used. For low-pressure valves (<25 bar) with a nominal bore larger than NB 250, cast-steel bodies shall be used.

Carbon steel shall be used for temperatures below 400 C. For temperatures above 400 C, alloy steel shall be used unless agreed by the Owner/Engineer.

All valves shall be designed to prevent erosion of the valve seats when the valves are operated in a partially open position.

- 6.70 -


In areas with increased hazard valve actuators shall be driven by air with spring to close feature. Only in well justified cases the use of electric actuators will be accepted in those areas. In this case explosion proof design is mandatory.

Spring load for pneumatic actuators shall be employed to facilitate safety during air failure, i.e. the valve is closed by spring force. However, in the case of the main inlet fuel system block and bleed valves, if there is a loss of air or electric power the valve shall lock in position. Only when there is a fire signal shall these valves “fail close”.

Valves with welding ends shall have ready machined ends, which shall match exactly the dimension of the pipe to which the ends have to be welded.

The welding ends shall be of the same material as the pipe and shall be long enough to allow heat treatment after welding, without the risk of damage to the valve by temperature increase.

All valves shall be installed in such a way that they can be easily operated by one person. Where required, valves spindles shall be sufficiently long, or extended in such a manner that the hand-wheel is at a level of approximately one meter above floor or platform level, from which the valve can be operated. Where required these shall be provided with headstocks and pedestals of rigid construction. Where extension spindles are fitted they shall incorporate two universal joints. All valve pedestals shall be mounted direct on floor girders and not on floor plating. All floor steelwork necessary for supporting pedestals shall be included. Installation with the valve stem oriented downwards/tilted is not acceptable.

All valve actuators shall have local indicators fitted to show whether the valves are in an open or shut position. In the case of valves being equipped with extended spindles, indicators shall be fitted to both the extended spindle and to the valve spindle. Motor driven valves shall have position indicators in the CCR.

Plastic or bakelite valve hand-wheels are not permitted.

The stops limiting the travel of any valve in the "open" or "shut" position shall be arranged externally to the valve body.

All valves shall be closed by turning the hand-wheel in the clock-wise direction when looking on top of the hand-wheel.

The face of each hand-wheel shall be clearly marked with the words "open" and "shut" in English, with adjacent arrows to indicate the direction of rotation to which each refers.

If, due to the use of a gear reducer, the valve has a spindle with a left-turn thread, this should be clearly marked.

Each valve hand-wheel shall be fitted with a name-plate of an approved material, indicating in English the valve reference number and function. The name-plate shall incorporate the colour code corresponding to the particular service of the piping.

- 6.71 -


Each valve shall be permanently marked with the code designation of valve, casing material, manufacturer’s serial number, nominal bore and the nominal pressure/test pressure and temperature (operating pressure and temperature from NP 63 onwards).

Hand-wheels equipped with electric servo motors, or hand-wheels of valves to which a servo motor may be fitted, shall not rotate when the servo motor is in use and shall furthermore, be able to be handled without being mechanically connected to the servo motor.

When determining the actuating forces, design pressure for one side and zero (0) bar pressure on the other side of the valve disc (i.e. full differential) shall be assumed.

Eye bolts shall be provided where necessary to facilitate handling heavy valves or parts of valves.

Valves shall be fitted with approved limit switches where required for interlocking purposes and to implement the control scheme as necessary for remote indication and control.

Spindles of valves for outdoor use shall have weatherproof protection covers. In general all valves exposed to the elements shall be corrosion resistant.

Test certificates for all valves shall be issued by the Manufacturer duly signed by the Inspection Authority.

6.11.10.7.2 Valve materials

Unless specified otherwise, the following requirements for valve materials shall be fulfilled.

Service Type Body Trim Remarks Fuel gas Ball (trunnion

mounted) Cast or forged steel ASTM 216 Gr. WCB or A350 LF2

SS ball 316.L of ENP

Conform to NACE MR-01-75 welded ends top/bottom entry

Fuel oil Ball (trunnion mounted)

Cast or forged steel ASTM 216 Gr. WCB or A350 LF2

SS ball 316.L of ENP

Top/Bottom entry – welded ends

DM water Diaphragm/stainless steel

Cast, forged steel/stainless steel

SS.316 L Flanged ends

Service water Gate Cast/forged steel 13% Cr/SS 304 Flanged ends Fire water Gate Cast/forged steel 13% Cr/ SS 304 Flanged ends Service air Ball Hot dip

galvanized cast steel

13% Cr/ SS 304 Screwed or flanged ends

Instrument air Ball Hot dip galvanized cast steel

13% Cr/ SS 304 Screwed or flanged ends

Chemicals Diaphragm Suitably lined steel

Flanged

Chilled water Gate/ball Cast/forged steel 13% Cr/SS 304 Flanged

- 6.72 -


6.11.10.7.3 Drain, vent valves and traps

Except for fuel gas and fuel oil piping all low and high-pressure drain valves shall be of a regulating type. For gas and gas oil service only ball valves shall be used.

All valves of NB 300 and larger shall be equipped with casing drain valves.

All material shall be resistant to all chemicals commonly used for acid pickling of the piping system.

Double isolation valves shall be provided on vents and drains of systems where the maximum operating pressure is 25 bar g or above, and for all pressures on hazardous services, such as fuel gas.

To drain the compressed air lines of condensed water and moisture suitable traps of the thermostatic-thermo-dynamic types shall be installed.

6.11.10.7.4 Safety and thermal relief valves

All sections of piping which can be subjected to pressure beyond the design value, eg due to change in temperature shall be provided with thermal relief valves.

If the piping downstream of a pressure reducing valve is of a lower design pressure then a pressure-relief valve shall be provided on the outlet side of each reducing valve capable of exhausting the maximum discharge of the reducing valve without undue build-up of pressure on the low pressure side. The discharge from the relief valve shall be led to a safe location. Pressure gauge and thermometers shall be provided up-stream and downstream of reducing valves.

Valves shall have been certified as acceptable by relevant codes and standards for the service and duty intended. The valves shall be high capacity, flat seated, reaction type with adjustable reaction rings, attaining full lift, spring loaded on top and having a maximum blow down of 4 per cent of the set gauge pressure and have flanged ends at inlets and outlets. Number, individual capacities, and set pressures shall be such as to exceed the minimum requirements of all relevant codes.

Where multiple valve arrangements are employed the valves shall have a combined flow rate equal to or more than 100 per cent of the maximum flow rate.

The actual pressure at which the valve is to lift shall be clearly marked on the valve.

Valves shall be equipped with lifting levers. Test gags shall be furnished for hydrostatic testing. Valves shall be factory set for pressure. A spare set of reaction rings shall be provided for each valve.

Great care shall be taken in routing the outlet pipe-work to ensure that the point of exit is not liable to cause a safety hazard.

Encased or bellows type relief valves shall be used if there is a build up of back pressure on the discharge side and to prevent leakage.

- 6.73 -


The valves shall have a test certificate issued by the manufacturer with inspection authority approval and shall be verified by site test.

All positive displacement pumps, shall be equipped with "safety-starting-relief valve" so that internal re-circulation of fluid is ensured during the pump start up and casing design pressure is not exceeded.

6.11.10.7.5 Pressure reducing and control valves

All pressure reducing and control valves shall be of an approved type and shall be perfectly stable, quiet and free from vibration in operation when pressure reducing any flow up to the maximum flow, and shall be suitable for continuous use at the operating temperature.

If the piping downstream of a pressure reducing valve is of a lower design pressure then a pressure relief valve shall be provided on the downstream (outlet) side of each pressure reducing valve which shall be capable of exhausting to atmosphere the maximum discharge of the reducing valve without undue build-up of pressure on the low pressure side. The discharge from the relief valve shall be led to a safe point. Pressure and temperature gauges shall be provided upstream and downstream of the reducing valve.

All control valves shall have a sufficient overload range. At full load and normal operation, the control valves shall be 70-80 per cent open. Valves shall be sized for flow requirements taking into account the appropriate CV factor.

Control valves for pressures over 25 brag shall be preferably single seat or cage type valve, with a body of forged steel with flanged end connections, and pressure sealing bonnet.

Valve class and material shall take into account pressure-temperature rating. Cast iron bodies for control valves will not be accepted.

Control valves, independent of their type, shall have a tight shut-off as per the applicable Standards.

With the exception of high temperature services, all control valve gland packing shall be of the self lubricating Teflon type. Inner valve trims shall be selected to suit best the process requirements.

Inlet/outlet isolating and bypass valves adequate for full flow shall be provided for control valves.

Manufacturer’s shop test certificates shall be furnished for the hydrotest of control and pressure reducing valve bodies and for the leakage rates across control valve seats. Valve characteristic curves shall be provided for each type and size of valve.

6.11.10.7.6 Motor operated valves

All motor operated valves shall be fitted with both hand and motor operating gears. Where a bypass valve is provided and this by-pass has to be operated each time the main valve is operated then this also shall be arranged with both hand and motor operating gears interlocked to

- 6.74 -


ensure that the bypass valve is opened before the main valve. Each valve shall be fitted with limit switches for automatically stopping the motor when the valve gate has reached the “fully open" or "fully closed" position. The motor shall be placed in such a position relative to the valve that there is no possibility of a leakage of liquids or corrosive gas from the valve joints into the motor or control equipment.

All power operated valves shall have position indication in the CCR.

The hand operating and motor operating mechanism shall be interlocked in such a way that the hand operating mechanism must be disconnected before the motor can be started. Valves shall be provided with seating control, and for small valves, a slip clutch or other torque limiting device shall be incorporated in the motor drive.

For details of the requirements for motor actuators, refer to Section 7.

6.11.10.7.7 Valves for demineralized water systems

Valves for the demineralized water systems shall be of the diaphragm type, either rubber lined cast steel or stainless steel.

6.11.10.7.8 Valves for fire protection and fire safe service

Valves for fire protection and fire safe duty shall be of designs specifically designed for the service and capable of receiving regulation approval; eg UL, FM etc.

6.11.10.7.9 Valves for water, drain and air services

All valves for water, drain and air services shall be of a make and design with materials of the internal parts all to the approval of the Owner/Engineer.

Sealing between the disc and body of butterfly type valves shall be renewable metal to rubber facings secured to the disc and body in an approved manner.

6.11.10.7.10 Valves for gas services

Valves used in fuel gas service shall be trunnion mounted ball valves, fire safe to API 607 and provided with antistatic device which shall ensure electric continuity between the ball stem and the body of the valve.

No aluminium or zinc alloys or similar low melting material shall be included in their construction. Valves up to 50 mm in size may be of the non-lubricated type, valves greater than 50 mm in size shall incorporate design features that enable lubricant to be injected under pressure between the plug and body whilst the valve is in service.

All valves shall incorporate sliding sealing surfaces such that further movement of the closing part is provided after gas shut-off. All valves shall provide reliable tight shut-off and be capable of easy operation after long periods in one position.

- 6.75 -


6.11.10.7.11 Valves for oil services

All valves intended for fuel oil or lubricating oil services shall be of cast or forged steel construction with flanged, butt weld, screwed or socket-welded ends. Welded on flanges will not be acceptable. All valves shall be fire safe and shall be provided with suitable features in the valve to ensure electrical continuity between the valve stem and the body of the valve. No aluminium or zinc alloys or similar low melting material shall be included in their construction. All valves shall provide reliable tight shut-off and be capable of easy operation after long periods in one position.

6.11.10.8 Pumps


All pumps supplied within the Contract shall be designed, manufactured and tested in accordance with the requirements of the relevant Standards and Codes. Unless specified otherwise, centrifugal pumps shall be designed, manufactured and tested in accordance with the relevant BS/ISO (ISO 5199, 9905 or 9908 as applicable) or equivalent internationally recognized standards.

The pumps shall operate satisfactorily when delivering varying quantities from minimum up to the design maximum flow and shall be constructed to ensure continuity of service, ease of inspection, cleaning and repairs, together with satisfactory operation under all climatic conditions prevailing at site.

Where duplicate pumps for the same service are provided they shall operate satisfactorily in parallel with each other.

All pumps shall be designed far maximum continuous operation conditions even at system frequencies between U+ U4 per cent of rated frequency. All pumps shall have a design margin of 10 per cent on flow and 20 per cent on head.

The characteristic curve of a centrifugal pump shall be stable under all conditions, ie the head shall increase with decrease in delivery until maximum head is reached at zero flow. Details of head and flow/performance characteristic curves shall be submitted for design review. The Net Positive Suction Head (NPSH) required at any capacity up to and including runout shall be at least 20 per cent or 1 m less than the available NPSH, whichever creates the greater margin.

The pumps shall be free from vibration at all load conditions and shall be designed to allow satisfactory and safe operation during all possible operating conditions, including cold and warm start-up and run out flow.

The pumps shall be designed in such a way that no leakage shall result from a change in fluid temperature. In general mechanical sealing systems shall be used throughout.

Material shall be specifically chosen to resist cavitation, erosion and corrosion, seizure or other destructive influences to which a pump may be subjected in service. If the pump impellers and the impeller shaft are of different material, any portion of the impeller shaft which could be in contact with the fluid must be covered by a sleeve of the same material as used in the impeller construction.

- 6.76 -


The general arrangements of the pumps, motors, supports, piping etc shall allow handling for maintenance with the least possible dismantling and joint breaking. All structures and foundations etc shall be designed, supplied, installed and tested under this Contract. This shall include steel wedges, levelling screws, support plates, foundation plates and anchor bolts, etc.

All leakages shall be collected and directed to suitable drain connections and discharge system.

Flexible coupling with guards shall withstand all service conditions and shall be arranged for easy disconnection and reassembly.

Suitable connections for instruments, drain and vents shall be provided.

6.11.10.8.2 Types of pumps

Horizontal spindle pumps shall be of the centrifugal type with fully balanced impellers and at least two bearings. The driving motors shall be mounted on an extension of the pump base plates. Base plates shall be provided with drip tray facilities and provision shall be made for drainage.

All pumps shall be capable of reverse rotation up to 125 per cent of rated speed due to back flow of fluid without causing damage to the pump, alternatively a reliable method of preventing reverse rotation shall be provided.

For certain services, the pump may be installed in a tank of suitable material which forms a well from which the pumps takes its suction. Such tanks will normally be cast in concrete, with the discharge flange above the floor level. Only the mounting and discharge flange bolts will require removal to pull the pump.

Portable sump pumps shall be of the heavy duty submersible self priming type, each complete with 10 meters of flexible hose, sealed-off electric motor and flexible power cable 20 meters long. The power cable/pump motor connection shall be completely waterproof when connected. All portable sump pumps shall be suitable for pumping dirty water which may be contaminated with fuel oil.

All positive displacement pumps shall be of the horizontal screw or gear type.

All positive displacement pumps shall be complete with electric motor driver, common baseplate, gear type flexible coupling and base mounted coupling guard, arranged for easy disconnection and reassembly and designed to withstand all service conditions. The pump/motor combination shall be non-overloading at 125 per cent of the normal system operating pressure at the maximum pumping viscosity value. Spacer type couplings shall be used if required to allow pump disassembly without moving the motor. All pumps shall be direct drive.

Pumps of the rotary screw type shall have two (2) or three (3) rotors in accordance with manufacturer’s standard. Externally lubricated indexing gears and bearings shall be provided.

- 6.77 -


6.11.10.8.3 General construction requirements

Air release valves shall be fitted where necessary at suitable points on the pump casing.

Each pump shall be fitted with isolating valves and pressure gauges to suction and discharge, and a non-return valve on the discharge line.

The following requirements are applicable to all pumps unless specifically noted otherwise in the particular system subsection.

a. Casing

Cast iron/cast steel/stainless steel casting for casing materials shall be used to suit the duty.

Connections between pump parts shall be doweled where necessary to assure proper alignment and fitted with gaskets of standard thickness and material selected for durability and compatibility with the pumped fluid.

The pump casings shall be horizontally split to allow easy maintenance, and suitable means shall be provided for withdrawing the removable top half casing and impellers without disturbing any of the connecting pipes or valves.

b. Seals

Shaft seals shall be of highest quality design and material. Ample room shall be provided for seal maintenance and/or replacement.

Unless specified otherwise, mechanical seals shall be used exclusively.

Precautions shall be taken to prevent seal leakage entering the bearing housings.

c. Bearings

Antifriction type bearings shall be provided as required by the particular pumps specification. They shall be amply sized to carry all loads applied and shall be designed for 100 000 hour rated life under design conditions.

Where bearings are of the ball or roller type the inner race shall be fitted directly to the shaft and shall be located at a raised machined shoulder of the shaft. Where the pumps are operated intermittently, special care shall be taken to prevent brinelling of the races while the pumps are not in operation. Intermediate shaft bearings for the suspended vertical type of pumps shall be securely connected to the main pump supporting tube. The weight of the pump impellers and shaft in addition to fluid axial forces shall not be taken by the motor bearings but by a separate thrust bearing for which ample access shall be provided for examination and maintenance.

- 6.78 -


All bearings shall be oil tight against the atmosphere. Provision shall be made at each end of the bearing to prevent oil or grease being thrown off outside the bearing housing or creeping along the shaft.

Bearings requiring cooling water shall be provided with all the necessary pipe work, valves and strainers for this purpose. All pumps shall have adequate thrust bearing provision.

d. Shafts

Impellers shall be mounted on shafts, keyed against rotation, and accurately positioned by collars or other suitable means. Shaft material shall be stainless steel 316 L unless specified otherwise.

e. Impellers

Impellers shall be accurately machined, statically and dynamically balanced to provide vibration-free operation. All surfaces shall be finished to a smooth contour. Impellers shall be of stainless steel 316 L unless otherwise specified.

f. Couplings

Each coupling half shall be keyed and properly fitted to it’s shaft. It shall be capable of absorbing variations in alignment and axial movements without affecting performance. It shall be adequately sealed to prevent entrance of sand or other foreign material.

All couplings and any intermediate or dummy shafting shall be efficiently guarded.

g. Wear rings

Renewable casing and impeller wear rings shall be furnished on all pumps and shall be of materials compatible with pump casing and impeller.

h. Workshop tests

All pumps shall be workshop-tested in accordance with the relevant BS/ISO approved standard, as noted above. Pump performance curves, based on actual tests unless prototype tests are accepted, shall be submitted for each pump in the quantity and manner set forth elsewhere herein.

6.11.10.9 Tanks and pressure vessels

Unless otherwise specified, tanks and pressure vessels shall be of welded construction, manufactured from carbon steel plate of accepted quality and thickness, and designed, constructed and tested in accordance with the appropriate BS, API, AWWA and ASME standards as applicable.

The tank supports - if any - shall be of such a height as to permit cleaning and painting of the floor plate of the tanks from the tank bottom. Tanks and vessels which are to be lagged shall be provided with external lugs for attaching reinforcement wire where necessary.

- 6.79 -


Prior to the application of internal protection the tanks and vessels shall be thoroughly cleaned, dried by hot air or other approved means and shall then be sandblasted and treated internally by processes as specified. Arrangements shall be made for the blanking off or removal of all valves or pipe connections during sand blasting to prevent the ingress of sand or other matter. The protective process shall be applied also to any ferrous fittings mounted inside the tanks.

All tanks and pressure vessels shall be painted externally, in accordance with the specified provisions. All equipment shall be earthed and cathodically protected where appropriate. Corrosion allowance for pressure vessels and tanks shall be 3.0 mm unless otherwise specified.

Tanks where appropriate shall be electrically isolated from cathodically protected pipe by insulating flanges or dielectric unions.

6.11.10.10 Bolts and nuts

All bolts and nuts etc. shall conform to the stipulated standards. Bolts or studs which are subjected to high pressure and temperature shall be high tensile alloy steel with nuts of a suitable, approved material, and shall comply with ANSI requirements for power piping.

All bolts or studs manufactured from alloy steels or steel shall be suitably machined at the shank and under the bolt head. Washers shall be provided under nuts, and also under bolt heads if required.

6.11.10.11 Thermal insulation


Unless otherwise stated all pipework, ductwork, casings, flues and equipment that transmits or receives heat, or will form condensate shall be insulated with asbestos free materials.

Heat insulation of all plant and pipe work having temperature of 65°C or more shall be provided to reduce the heat loss to atmosphere to a minimum, reduce the cooling load on the air-conditioning system, and to afford operational safety to the personnel. Where applicable the heat insulation shall be made of prefabricated formed lagging. Otherwise, insulation mats stitched on a mesh of galvanized wire shall be used. The insulation material shall consist of non-combustible and chemically inert material. The aim is to achieve an optimum reduction in heat loss by providing insulation of the appropriate type and thickness.

Personnel protection insulation and protective covering shall he provided on piping and equipment where heat loss is inconsequential and where the surface temperature may exceed 60°C.

All piping, valves and equipment which contain chilled water shall be covered with approved anti-sweat insulation, comprising a vapour resistant barrier jacket.

Furthermore, the thickness shall be chosen in such a way that a heat loss of 230 watts/mP

2P

is not exceeded.

That calculation of thickness and thermal conductivity shall be subject to approval by the Owner/Engineer.

- 6.80 -


All insulation shall be installed with proper allowance for expansion and insulation exposed to the weather shall be installed with proper flashing so as to keep the insulation dry at all times.

The Contractor shall exercise extreme care in storing and applying insulation to make sure that it remains dry until water proofed. Insulation materials shall be stored in an enclosed area and shall always be stored in original containers until ready for application. Insulation that has become damp shall not be applied.

Before applying the insulation, all piping vessels and equipment shall be tested for leaks and repaired, if necessary. Metal surfaces to be insulated shall be free from rust, grease, dirt, frost and moisture.

Insulation shall not be applied to any vessel or equipment until all tests have been made, leaks repaired and tests accepted.

Piping shall be covered with pre-formed half-cylindrical or curved segments of insulation materials. Insulation shall be applied with the circumferential joints staggered for single layers and with both the circumferential and longitudinal joints staggered for double layers. Each layer shall be securely wired. All joints of each layer and any voids or irregular surfaces shall be filled with insulating cement so that the surface will be cylindrical and smooth before the next layer or jacketing is applied. This principle shall be applied to every application.

Covering on vertical runs of pipe shall be supported in such a manner as to prevent displacement due to slipping or contraction. This shall be accomplished without welding to pipes.

Flange covers shall be made of sectional pipe covering or block insulation. These flange covers shall be made removable and to the thickness of the pipeline covering. Sufficient space next to flange shall be allowed for bolt removal.

All valves and fittings shall be covered with insulating material of the same kind and thickness as that specified for the pipeline in which they are installed or by plastic insulating cements. The surface shall be coated with a vapour barrier cement or mastic and covered as appropriate. The final outer layer shall be aluminium cladding so as to be completely weatherproof. In the case of reducing fittings the largest pipe size shall determine the thickness of the material to be used. Insulation shall be removable.

On equipment with regular surfaces such as tanks and vessels, calcium silicate blocks shall be applied. Layers shall be secured on the shells with stainless steel bands on 225 mm maximum centres machine stretched, and clamped in place under tension. Where multilayer application is required, all joints are to be staggered over joints of preceding layer. Heads of vessels are to be insulated with flat block insulation and secured with bands on 300 mm maximum centres attached to a double layer of circumferential bands or to rings welded to the vessels. Where removable head covers are required for exchanger head removal, the covers shall be field fabricated to allow access to these areas without disturbing adjacent insulation. Equipment insulation is to be covered with aluminium jacketing as specified for piping. Longitudinal and circumferential seams shall be lapped a minimum of 75 mm. Insulation shall be cut away from markings such as nameplates,

- 6.81 -


clips, code inspection plates, etc, sealed and flashed against the entrance of water. Insulation and metal covers for manholes and blind flanges where required shall be two-piece removable covers.

Skirts and supporting legs on equipment shall not be insulated. Longitudinal expansion of vessels shall be provided for by installing expansion joints. Nameplates on insulated equipment shall be removed and reinstalled by the Contractor on outside of covered surface in a secure manner satisfactory to the Owner/Engineer. Code stampings on pressure vessels shall be insulated with a removable section of insulation and lagging for easy accessibility for inspection. The Contractor shall furnish and install all insulation clips.

All instrument connections on pipes, ducts, vessels or equipment shall be insulated. The insulation shall be shaped at these connections by tapering it to and around the connection with insulating and finishing cement.

All access doors, removable panels, manhole covers and other parts on equipment requiring insulation, which must be opened or removed, shall be insulated. The method of insulating removable parts shall be such as to eliminate damage to the insulation on the removable part and on the adjacent surfaces. Edges and corners shall be protected by light structural angles or metal strips, and wire mesh shall be employed where necessary to hold the insulation securely and permanently in place.

6.11.10.11.2 Materials for heat insulation

The material used shall withstand the specified temperatures without deterioration shrinkage, change in form or pulverization.

a. Heat insulation

Heat insulation materials shall be calcium-silicate in the form of flat or curved blocks for equipment and in the form of half-cylindrical or curved segments for piping. The materials shall meet the requirements of ASTM-C533, Type I or equivalent. The use of preformed insulation materials shall be maximized when fabricating covers on valves, fittings, flanges, vessels, etc. The Contractor shall ensure a satisfactory fit on all piping and tube sizes to accommodate thermal expansion.

b. Finishing cement

If required finishing cement shall consist of asbestos free mineral fibre and suitable fillers premixed with a hydraulic setting binder. It shall be compatible with adjacent insulating materials and conform to ASTM-C449 or equivalent. When mixed with water, it shall form an easily workable plastic mix suitable for trowel application. After drying, it shall present a hard, smooth and durable surface free of cracks.

- 6.82 -


c. Wire-mesh and binding wire

Wire mesh shall have hexagonal openings of 10-20 mm nominal size. It shall be woven of No 20 wire gauge from stainless steel wire. Binding wire shall be of stainless steel and not smaller than No 16 SWG.

d. Aluminium for jacketing

Aluminium sheets shall be of alloy type, resistant to seawater corrosion, medium hard. Embossed material with vapour barrier shall be used for cladding over thermal insulation with a minimum thickness of 1.2 mm.

e. Mineral wool

Mineral wool shall be used for loose insulation where use of prefabricated blocks is not possible. The mineral wool shall be stitched on one side to wire mesh by means of stainless steel wire. The material shall comply to the following specification:

The mineral wool shall not contain any sulphur, or other corrosion causing materials ie it should be resistant to acid, hot water and steam. The mats shall have good resistance to shocks. The fibre of the mineral wool shall not be destroyed under the influence of long-term mechanical vibrations.

6.11.10.11.3 Frost protection (if applicable)

The plant shall be adequately protected against frost damage.

Particular attention should be given to pipework, pump casings, etc, and any part of the plant and equipment likely to stand for periods charged with static water. Water used in closed circuits shall be treated with an approved anti-freeze compound.

All water pipework, pumps, valves, etc situated out of doors shall be protected against frost damage by thermostatically controlled electric trace heating and approved weatherproof insulation. The trace heating shall energize automatically when the ambient air temperature drops to 3°C and shall maintain the system at a temperature no lower than 3°C. The trace heating supply shall be energized at 110 V 50 Hz, centre point earthed, utilizing on approved proprietary system.

The trace heating system shall be installed in sections such that failure of one section does not affect other sections of the heating system. Local panels shall indicate when each section of heating is energized and failure of any section such that the faulty section can be readily identified. An alarm shall be raised when a fault occurs and transmitted to the PCS system in the central control room.

Insulation shall be suitable for outside installation and completely impervious to all weather and atmospheric conditions on the works. Lagging materials containing asbestos shall not be used.

- 6.83 -


The lagging shall be sectional and easily removed for maintenance purposes. Joints shall be sealed together with an approved waterproof adhesive tape.

6.11.10.11.4 Finishes

Protective covering shall be applied to all heat, personnel protection, and anti-freeze insulation. The materials for anti-sweat insulation shall be highly effective in preventing sweating and capable of satisfactorily withstanding moisture, and shall therefore not require additional protective covering.

Metallic cladding and weather proofing shall be applied to all insulated surfaces where practicable. Longitudinal and circumferential joints for lagging shall be lapped to a minimum of 75 mm. Longitudinal laps shall be generally located on the horizontal centreline of horizontal runs of pipe. The outer part of the lap for all horizontal joints and circumferential joints in vertical runs of piping shall be turned downward in order to shed all water from the joint. Jackets shall be secured with stainless steel sheet metal piping screws on l00 mm centres on longitudinal joints.

Elbows, bends and fittings shall be provided with cladding made from individual segments. The covering shall be furnished with neatly cut-off openings with separate sheets collars for the pipe hangers and other pipe connections/tappings.

On bends, fittings valves and on equipment where a minimum overlap of aluminium is not possible, special workmanship such as beaded and crimped edges, shall be employed to produce a weatherproof covering.

6.11.11 Steelwork

All supporting steel structures shall be provided for plant, ducting, pipework and galleries, including pipe support brackets.

All necessary platforms, toe-plates, ladders, stanchions, handrails, chains and all associated fittings shall be supplied to provide a safe and efficient installation.

All mild steel items shall be protected by hot dip galvanizing after fabrication to BS EN ISO 1461 with a minimum thickness of 85 microns, unless otherwise specified.

No cutting, drilling, bending, riveting, threading or similar operation will be permitted after galvanizing, and due care shall be exercised in transporting, handling and fixing galvanized metalwork to prevent damage to the zinc coating. Under no circumstances shall damage to the zinc coating be repaired with rust inhibiting paint.

6.11.11.1 Platforms

Platforms shall be constructed using galvanized open steel flooring to the relevant British Standards and shall cater for the relevant loadings for maintenance. The minimum acceptable size being 30 mm deep, 3 mm thick bars at 42 mm bar spacing. The flooring shall be bolted to the framework using approved bolted clips. The platform framework shall be galvanized.

- 6.84 -


Platforms shall be provided and toe plates fitted to all platform edges. All platform panels shall be individually secured and be of suitable size and weight for ease of handling.

Plated flooring shall be chequer plate having a minimum base thickness of 8 mm with a non-slip tread pattern, secured to the supporting steelwork with countersunk screws, which shall be cadmium plated. For manoeuvring small-wheeled items eg switchboard trucks, plain floor sheeting 8 mm minimum thickness shall be provided over specified areas.

Open mesh platforms shall be open type, galvanized mild steel flooring suitable for a loading of 15 kN/mP

2P supported by heavy duty curbing giving a landing of 35 mm.

Hinged grating with facilities for securing in the open position shall be provided as necessary.

6.11.11.2 Ladders and stairways

Access ladders shall be provided as required. Step type ladders shall have flat section, non-slip, open type treads not less than 450 mm wide between stringers, with handrails fitted to each side extended to meet the platform handrails at the upper end.

Vertical fixed ladders for emergency use shall be in accordance with BS 4211 with equally spaced rungs between 230 and 260 mm apart with a width between stringers not exceeding 400 mm. Safety hoops shall be provided where necessary.

Stairways shall be not less than 760 mm wide between stringers, and have an inclination to the horizontal not exceeding 40°. The stairways shall be constructed of galvanized mild steel stringers with galvanized open steel treads, reinforced at the leading edges, supported by substantial structural members. Galvanized handrails and standards shall be provided on each side of the stairway.

6.11.11.3 Stanchions, handrails and chains

Handrailing shall be 25 mm bore, with welded joints carried on solid forged steel handrail standards all galvanized with the upper rail not less than 1.1 m above the platform level. Ball type tubular standards are to support the handrails at not more than 1.5 m centres and arranged so that there is a standard not more than 300 mm away from any bend and 150 mm from any handrail joint. Handrails are to be secured to prevent movement within the standards. Stanchions and handrails shall be attached to the platform/walkway frame and not to any non-structural floor or toe-plates.

Wherever possible, runs of handrail shall be continuous and sharp vertical changes of direction shall be avoided. Handrails shall terminate in swept ends either to the wall or return to the knee rail by means of a U bend which shall not extend greater than 350 mm beyond the centre line of the last standard.

Entry points to ladders and platforms where necessary shall be protected by a double row of safety chains of mild steel 3 swg × 3 links per 100 mm complete with ‘S’ hook attachments.

- 6.85 -


6.11.11.4 Toe-plates

All platform and walkway frames shall have toe-plates attached to the sides where handrails are fitted. Only around cut-outs provided in floor plates shall the toe-plate be secured the floor plate by welding.

Toe-plates shall be at least 100 mm high and 5 mm thick and the gap between toe and floor plates shall not exceed 15 mm.

6.11.12 Safety guards for plant and apparatus

Guards to ensure safety of personnel shall be provided to the approval of the Owner/Engineer and shall be generally in accordance with BS 5304.

6.12 Packing and marking on packages

All apparatus shall be carefully packed for export shipment and storage at Site in such a manner that it is protected against all climatic conditions.

All tubes and pipes shall be protected from external damage and to prevent ingress of dirt during transport and storage. The Contractor shall submit details for approval of the proposed methods of protecting the individual pipe ends before any pipes are despatched to Site. Wood plugs shall not be used for sealing the ends of tubes. When tubes are to be stored on Site they shall be placed on supports so that they are not in contact with the ground.

All bright parts liable to rust shall receive a coat of anti-rusting composition and shall be suitably protected. Special precautions shall be taken to protect journals where they rest on wooden or other supports likely to contain moisture. At such points wrappings shall be used impregnated with anti-rusting composition and of sufficient strength to resist chafing when subjected to the pressure and movement likely to occur in transit. Motors and equipment with ball or roller bearings shall be protected with resilient packing to prevent damage due to vibration.

The packing cases and packing materials are included in the Contract and shall be the property of the Owner.

6.12.1 Receipt and storage at site

All items, packing cases, containers and packages received at Site shall be recorded against the shipping schedule and immediately inspected for signs of damage. All signs of damage shall be investigated and the extent and nature of the damage recorded. The contents of each packing case, container or package shall be checked against the contents list and any discrepancies noted. Each item shall be carefully unpacked and checked for mechanical damage and/or damage to the corrosion protection. All such damage shall be recorded.

No item will be accepted for storage on Site until all mechanical and/or corrosion protection damage has been notified and rectified to the Engineer’s satisfaction. It is emphasized in this respect that for damage which may affect the life or function of the component the Contractor must submit a full report to the Engineer describing the consequences of the damage and the proposed rectification procedures.

- 6.86 -


All plant and equipment to be stored out of doors shall be placed on timber or the equivalent so that it is out of contact with the ground and provided with adequate protection against weather. The Engineer may, if he considers it necessary, instruct the Contractor to carry out a repair or special cleaning process on any item on which the protection has been ineffective and/or which has been subjected to adverse storage conditions.

All items stored at Site shall be inspected on a regular basis and adequate records of inspection and corrosion protection rectification carried out shall be kept. All such records and the items in store will be subject to periodic audit and inspection by the Engineer who may require additional work to be carried out to either restore the condition of the item or to ensure that deterioration does not occur.

The cost of all recording, inspection and rectification shall be borne by the Contractor who is also responsible for any necessary insurance claims against shipper and/or other parties in respect of the damage to or loss of any item or component.

On withdrawal from store, each item or component shall be prepared for erection by removal of temporary shipping and site storage protection. Immediately prior to erection, inspection shall be carried out to ensure that all such protection has been properly and completely removed as necessary unless the protection is to be used for additional protection during erection. All such ‘left on’ protectives must be removed prior to commissioning the plant unless with the specific approval of the Engineer they will be removed during testing and/or commissioning without detriment to the plant or associated plant and equipment. All desiccants and vapour phase inhibitors must be removed prior to erection even though semi-completed systems and/or vessels may subsequently require re-protection by similar means to prevent deterioration during erection.

The Contractor shall be held responsible for, and make good, all damage occurring due to improper preparation of goods for shipment or storage.

6.12.2 Erection mark

All members comprising multipart assemblies, eg steel framework, piping installations, etc. shall be marked with distinguishing numbers and/or letters corresponding to those of the approved drawings or material lists. These erection marks, if impressed before painting or galvanizing, shall be clearly readable afterwards.

Colour banding to an approved code shall be employed to identify members of similar shape or type but of differing strengths or grades.

- 7.1 -


7. ELECTRICAL

This part of the specification details the requirements for the electrical plant and all associated auxiliary equipment, and the criteria against which the equipment shall be designed.

The electrical system shall be designed on a unitized basis, the only possible interconnections being at low voltage level where an essential supplies/common board may service more than one unit. The black start facility shall not be used as a point of interconnection.

Fault studies have been carried out by others, the results of these studies will be made available upon request. The scope of supply of electrical equipment is covered in Section 3.

7.1 Generators

The generators shall be two pole synchronous machines and shall comply with the requirements of IEC 60034-3. Each generator shall be of an established design having a proven record of reliability for similar applications. The generators shall be preferably of the totally enclosed water to air cooled type (TEWAC), however alternative methods of cooling will be considered according to the contractors standard design. The cooling water for the generators shall be supplied from a closed circuit cooling water system.

Each generator shall have a rated output and capability which shall equal or exceed the capability of the respective turbine output over the full specified operating range of air temperature and cooling water at site, and should not under any condition, limit the possible output of the plant.

Each generator shall be capable of generating rated active power over the range of power factor from 0.85 lagging to 0.95 leading.

Each generator shall be capable of supplying it’s rated output at rated frequency and rated power factor for a voltage range of ±5 per cent at the generator terminals, and shall also be capable of supplying it’s rated output at rated voltage and rated power factor at a frequency which may vary between 48.5 Hz and 51.5 Hz.

The short circuit ratio shall be not less than 0.5.

The stator and rotor insulation systems shall be to Class 155 (F) in accordance with IEC 62114 but the relevant temperature rises and total temperatures shall not exceed the limits for Class 130 (B).

In designing the layout of the power station particular attention shall be paid to ensuring free access for the complete withdrawal of the generator rotor. It shall also be possible to remove and reinstate the generator stator with the minimum disruption to adjacent plant and equipment. Any special equipment necessary for rotor and stator handling shall be provided.

On line condition monitoring equipment for the stator winding insulation system shall be provided for each generator.

- 7.2 -


7.2 Excitation system and equipment

Each generator shall be provided with a static excitation system. The system shall utilize a three phase fully controlled thyristor bridge rectifier energized from the machine terminals through a suitable transformer. The system shall comply with the requirements of the relevant IEC standards.

The excitation system shall be capable of supplying the specified ceiling excitation for a period of not less than 10 seconds following full load operation with the generator subsequently returning to full load operation

The excitation system shall be complete with all the necessary control, monitoring and protection equipment to enable operation from the central control room.

The rectifier and AVR equipment shall be located in an air conditioned enclosure, adjacent to the respective turbine unit. Cubicles shall have a minimum degree of protection of IP54.

A fully controlled three phase, six pulse thyristor bridge rectifier shall be provided. Spare capacity shall be built into the equipment to allow uninterrupted operation during the period between generating set overhaul outages. Any rectifier failures during this period shall not place a restriction on steady state or transient performance. The design shall allow easy replacement of thyristors and fuses if used.

Where forced air cooling is considered necessary, main and standby fans shall be provided. To reduce the risk of bearing damage in stationary fan units, both fans shall either run continuously or be subject to cyclic operation. Hot air shall be ducted outside of the equipment area.

The excitation transformer shall be of the three phase, cast resin type, suitable for indoor installation and shall comply with the requirements of IEC 60076, 60146 and 60726. The transformer shall be housed in a naturally ventilated steel enclosure, located below the IPBs.

The excitation system shall include a continuously acting automatic voltage regulator, with no dead bands. The regulator shall have dual automatic channels together with manual control facilities for commissioning and maintenance. An auto following control function shall be provided to ensure smooth transfer between automatic channels. The voltage reference signals for the two automatic channels shall be provided from separate sets of VTs.

Local and remote set point control shall be provided for automatic control, with local control provided for manual operation. Appropriate auto/manual changeover facilities shall be provided.

Limiters shall be provided for underexcitation, overexcitation and overfluxing. Each limiter shall have adjustable settings. Circuits shall be provided for reactive load sharing with other machines and line drop compensation. A power system stabilizer and a reactive power controller shall also be provided.

Field suppression equipment shall be provided to rapidly reduce the excitation of the generator to zero in response to a trip signal or a circuit breaker open signal. The field suppression

- 7.3 -


equipment shall operate independently from the excitation control equipment. It shall be housed in a cubicle and form part of the excitation equipment cubicle suite.

7.3 Generator main connections, neutral earthing and switchgear

7.3.1 General

Connections between the generator and the respective generator transformer, unit transformer, and excitation transformer shall be isolated phase busbar. Facilities shall be provided for VTs and CTs where necessary. The connections shall be designed to withstand full asymmetrical peak currents under short circuit fault conditions. Neutral connections shall be designed for full phase to earth voltage, and shall be adequately rated to take the full unrestricted fault current for three seconds.

The busbar installations shall comply with IEC 60071, IEC 60105, and IEC 60298.

Induced currents in adjacent structures shall be kept to a minimum.

A means of preventing electrolytic corrosion shall be provided where the conductor is connected to a dissimilar metal.

The enclosures shall be completely weatherproof. Flexible connections shall be used to connect the busbar to generators and transformers. Dry filtered air shall be used to pressurize the busbars, with an alarm to the plant control system for high and low pressure.

Voltage transformers shall either be integral to the generator circuit breaker, or positioned in a ground mounted phase isolated cubicle. CTs shall be located within the generator terminal enclosure. CTs and VTs shall be provided for statistical metering, protection, control, instrumentation, and AVR channels A and B.

Earthing of the busbars shall comply with IEEE 665.

Cubicles which form part of the IPB system shall be complete with anti-condensation heaters.

7.3.2 Generator switchgear

Generator switchgear shall be designed for incorporation into the isolated phase busbar system.

The circuit breaker shall be manufactured and tested for generator switching duty in compliance with IEEE C37.013.

Where SF6 gas is used it shall conform to the requirements of IEC 60376. Portable top up/recharge equipment shall be supplied. The circuit breaker shall be equipped with a low gas pressure alarm. It shall be possible to remove each pole individually.

An earthing switch shall be provided on each side of the circuit breaker. A disconnector shall be provided as part of the unit on the generator transformer side of the circuit breaker. A

- 7.4 -


disconnector for a connection to a static frequency converter shall also be provided, where this device is employed.

7.4 Transformers

7.4.1 General

All three phase transformers shall be of core type construction. Transformers for indoor installation shall be dry type. All transformers shall be complete with all accessories and necessary auxiliary equipment. All transformers shall comply, and be rated in accordance with IEC 60076 or IEC 60726 where appropriate.

The terminal arrangement and connections shall not restrict access for maintenance and inspection.

All transformers shall be capable of operating continuously without damage between 48.5 Hz and 51.5 Hz.

All windings below 72.5 kV shall be fully insulated.

When the generator circuit breaker is open either the generator transformer or unit transformer shall provide voltage control of the MV system voltage.

The LV terminals of the generator transformer, and HV terminals of the unit transformer and excitation transformer shall be arranged for connection of isolated phase busbars.

Cable boxes shall be suitable for the connection of XLPE or EPR insulated cables. The body of the cable box shall be provided with an earthing bolt or stud. Cable boxes shall be air insulated. Phase segregated cable boxes shall be used for single core cables. LV terminals of auxiliary transformers shall be fully insulated.

7.4.2 Dry type transformers

Dry type transformers shall have Class 155 (F) insulation, but the relevant temperature rises and total temperatures shall not exceed the limits for Class 130 (B) under all site and operational conditions, and an enclosure to IP31.

7.4.3 Oil filled transformers

Generator transformers shall be rated to match the generator continuous maximum output over the full range of taps and system voltage under all site ambient conditions.

Generator transformers shall have ONAN/ONAF cooling. The ONAN rating shall be 60 per cent of the ONAF rating. The cooling fans shall be automatically controlled. The maximum hot spot temperature of the generator transformer under all site and operational conditions shall be 98°C. The cooling system shall be provided with failure alarms.

- 7.5 -


Oil filled transformers shall be fitted with lockable drain valves to enable all oil filled compartments to be drained, and adapters shall be provided for connection to oil filtration plant. Sampling devices shall also be fitted independently of the drain valves. It shall not be possible for:

a. the oil in the diverter switch compartment to mix with oil in any other compartment,

b. the oil in the sealing end chambers to mix with that of the main tank.

First filling of oil shall be provided for each oil filled transformer. The grade of oil shall comply with the requirements of IEC 60296. Oil filtration equipment shall be provided for the largest transformer.

Silica gel breathers shall not use cobalt chloride.

Pressure relief devices shall be provided on each oil filled compartment. These devices shall discharge oil at ground level. Alarms shall be repeated to the plant control system.

Safe access shall be provided to generator transformer conservators and Buchholz relay. This shall take the form of an access ladder with hoops.

Radiators which are connected directly to the tank shall be detachable. Radiators which are mounted separately shall be mounted on a concrete base.

Tap position indicators for on load tap changers shall be provided both locally and remotely at the plant control system. On load tap changers shall be installed on the HV winding and comply with IEC 60214.

All oil filled transformers shall be fitted with an oil temperature indicator that can be manually reset. Alarm and trip facilities shall also be provided.

Marshalling kiosks for oil filled transformers shall be complete with temperature indicators, test facilities, interposing relays for supervisory control, control and protection for cooling plant with an auto-manual changeover switch. Each generator transformer kiosk shall include a single phase and a three phase socket.

Sealing end chambers shall be oil filled, and be provided with removable covers. The chambers shall accept the cable sealing ends, and provide testing facilities for the cable. The main conservator tank shall maintain the oil level in the sealing end chambers.

Bushings that house current transformers shall be arranged so that they can be removed without disturbing the current transformers, secondary terminals, connections or pipework.

The construction and mounting of all bushings shall ensure that, in the event of flashover, current has a definite path around joints fitted with gaskets. On capacitor type bushings a tapping shall be brought out to a separate terminal for power factor testing at site. The terminal shall be earthed when the weatherproof cover is in position. Stress shields shall be regarded as part of the bushing assembly.

- 7.6 -


Internal connections to transformer bushings shall be flexible.

On line condition monitoring equipment shall be fitted to transformers with ratings greater than 20 MVA.

7.5 Switchgear

7.5.1 General

All ancillary equipment within the switchgear shall comply with IEC 60947.

The overall height of switchboards shall not exceed 2.5 m.

All switchgear shall be accessible for maintenance without the need for extensive removal of internal equipment.

Indoor equipment shall have a degree of protection to IP41, outdoor equipment shall be IP55.

It shall not be possible to accidentally access live parts of the equipment.

Control sections and cable compartments shall be provided with internal lighting.

Each LV switchboard shall complete with a control circuit transformer. The primary winding, and the non earthed pole of the secondary winding shall be connected through a fuse.

Internal wiring shall be run in LSF trunking. No more than two wires shall be connected to one terminal. Wires shall be identified at each end. Wiring above 50 V, or wiring connected to pilot cables shall be segregated from other wiring.

Terminal blocks shall be stud or insertion type. Spare terminals shall be provided. All terminal blocks shall be labelled with a unique identification reference.

All indicating instruments shall be in accordance with IEC 60051 Class 1.0. Motor ammeters shall be capable of withstanding motor starting currents. Voltage operated instruments shall be protected by a fuse.

7.5.2 MV switchgear

MV switchgear shall be metal clad vacuum or SF6 type and comply with IEC 60056 and IEC 60298. The switchgear shall be dead front type.

The MV switchgear will normally be controlled from the plant control system.

Circuit breakers shall be fully withdrawable for maintenance and isolation purposes. VTs shall be supplied through fuses on the primary side. It shall be possible to remove the fuses without dismantling the equipment. Each compartment shall be padlockable.

- 7.7 -


Cable and busbar earthing facilities shall be provided. Busbar earthing shall be electrically interlocked.

The short time rating shall be in accordance with the results of fault studies.

Busbar and circuit shutters shall be individually operated and able to be independently padlocked closed.

All auxiliary switches shall be wired to a fixed terminal board.

Suitable handling equipment shall be provided for circuit breakers.

Mechanical or electrical safety interlocks shall be provided for isolation and maintenance and to avoid unsafe switching conditions.

A steel cabinet shall be provided for tools and maintenance equipment, and a separate cabinet shall be supplied for keys and padlocks. Each room in which MV switchgear is installed shall be provided with an insulated hook.

7.5.3 LV and dc switchgear

LV switchgear shall be free standing, and Form 4b in compliance with IEC 60439-1.

The LV switchgear will normally be controlled from the plant control system.

Circuit breakers shall be air break, and horizontally withdrawable. All motor starters and feeder cubicles shall be fully withdrawable.

The short time rating shall be in accordance with the results of fault studies.

Contactors shall be capable of withstanding the motor stalled current until the associated protection device operates. Contactors shall comply with IEC 60439-4.

Busbars shall be copper, and shall comply with IEC 60439-2. Busbar insulation shall be in accordance with the relevant phase colour.

All auxiliary switches shall be wired to a fixed terminal board.

Composite fuse and switch equipment in the form of either a fuse-switch or switchfuse shall comply with IEC 60439-3.

Suitable handling equipment shall be provided for circuit breakers or starters which weigh more than 25 kg.

Mechanical or electrical safety interlocks shall be provided for isolation and maintenance and to avoid unsafe switching conditions.

- 7.8 -


7.6 Current transformers

All current transformers shall comply with IEC 60044-1. CT secondary windings shall be earthed at one point only through an accessible link. The secondary windings shall have a 1 A or 5 A rating as appropriate. Facilities shall be provided to allow primary injection testing with minimum disturbance to the equipment. The following accuracies shall be used:

a. Tariff metering Class 0.2S

b. Instruments Class 1.0

c. Differential protection Class X

d. Other protection Class 5P

7.7 Voltage transformers

All voltage transformers shall comply with IEC 60044-2. For MV applications the primary windings shall be connected through renewable fuses. The secondary winding of all VTs shall be provided with an accessible phase coded fuse or miniature circuit breaker. VT secondary circuits shall be complete and earthed at one point only. It shall not be possible to connect VT secondary circuits in parallel where the VTs are connected to different sections of busbar. The following accuracies shall be used:

a. Tariff metering Class 0.2S

b. Instruments Class 1.0

c. Protection Class 1.0/5P

7.8 DC supplies system

Each generating unit shall have two dc systems other than that for the gas turbine. One system shall be for switchgear supplies and control equipment, the other being for telecommunications systems. Each system shall have a fully rated battery and two 100 per cent rated chargers. The batteries will normally be connected to the load in parallel with the chargers, and will supply the loads when ac supplies to the chargers are lost.

Each battery shall be capable of supplying its associated connected load for a period of one hour.

Each battery shall be complete with stands, all intercell connections, and connections between the battery terminals and the switchgear.

Indicating lamps shall be provided on the equipment to indicate battery faults, the faults shall also be remotely indicated to the plant control system.

- 7.9 -


Battery chargers shall have natural cooling. It shall be possible to carry out maintenance on one charger with the other in service. Each charger shall be capable of recharging the battery within eight hours after a complete discharge.

The battery rooms shall be adequately ventilated to ensure that the level of hydrogen gas present is less than 1 per cent.

7.9 Uninterruptible power supply equipment

The UPS equipment shall have isolation facilities to permit full replacement without disrupting any part of the system to which it is normally connected.

The equipment shall be complete with local alarms and a common alarm shall be repeated to the plant control system.

The UPS shall comply with IEC 60146-4.

7.10 Protection

7.10.1 General

There shall be two sets of main protection such that the loss of one set or failure of one set to clear a fault will not result in time delayed tripping of switchgear.

High speed discriminative protection systems shall be engineered as complete schemes, with due account being taken of current and voltage transformer performance.

All relays performing a measuring function shall be of numerical design with continuous self-monitoring.

Numerical relays and schemes provided shall all be suitable for connection to a local communications network, and provided with an integral local user interface.

Protection relays shall be type tested in accordance with the relevant sections of IEC 60255. Each protection relay shall have means by which the user can apply the settings, and a unique identifier which is clearly visible.

All back up protection systems shall be able to discriminate with main protection systems, circuit breaker fail protection (if fitted) and other back up protection systems installed elsewhere on the system.

Adequate facilities shall be provided within the protection scheme to enable the protection equipment to be tested from the front of the protection equipment panel with the primary circuit(s) in service with test points clearly labelled.

The protection system shall operate satisfactorily when tested to IEC 60068-2, IEC 60255-21, and IEC 60255-22.

- 7.10 -


7.10.2 Generator protection

As a minimum, the generator protection shall comprise the following functions:

a. Differential

b. Generator overload

c. Stator earth fault (100 per cent)

d. Rotor earth fault

e. Underfrequency

f. Overfluxing

g. Overvoltage

h. Loss of excitation

i. Reverse power

j. Negative phase sequence

k. Out of step

l. Dead machine energization

7.10.3 Generator transformer protection

As a minimum, the generator transformer protection shall comprise the following functions:

a. Differential

b. Restricted earth fault

c. Standby earth fault

As a minimum, the following supplementary generator transformer main tank protection devices shall also be provided:

i. Buchholz

ii. Overtemperature

iii. Overpressure

iv. Oil level

Generator transformers with cable sealing end chambers on the HV side shall be provided with a Buchholz for each chamber.

- 7.11 -


A Buchholz shall be provided for on load tap changers.

7.10.4 Unit transformer protection

As a minimum, the unit transformer protection shall comprise the following functions:

a. Differential

b. LV earth fault

As a minimum, oil filled unit transformers shall be provided with the following supplementary protection devices:

i. Buchholz

ii. Over-temperature

iii. Overpressure

iv. Oil level

7.10.5 Dry type transformer protection

Dry type transformers used as unit transformers for small gas turbine installations shall be provided with the following protection functions as a minimum:

a. Differential

b. LV earth fault

All dry type transformers shall be provided with winding temperature protection.

7.10.6 Black start/emergency diesel generator protection

The generating unit shall be provided with protection equipment which shall protect the generating plant from damage due to fault conditions. All relays or similar equipment for overspeed, oil pressure, cooling water level and high cooling water temperature, directly associated with the prime mover shall be mounted on the generating set engine and associated with a suitable trip relay. Protection equipment shall be provided and arranged to trip the associated circuit breaker, suppress the excitation and shut down the prime mover if faults should occur. The generator shall be provided with the following protection functions as a minimum:

a. Differential

b. Reverse power

c. Loss of excitation

d. Negative phase sequence

- 7.12 -


7.11 Synchronizing

Each generating set shall be provided with an auto-synchronizing scheme, synchronizing the generator across the generator circuit breaker. It shall also be possible to synchronize across the relevant EHV circuit breaker.

Each scheme shall be provided with a check synchronizing relay and selector switch for manual, auto, test and off. The test position shall be a simulation of the circuit breaker closing.

7.12 Black start/emergency diesel generator

The black start/emergency diesel generator shall be a direct injection, compression ignition, turbocharged and charge air cooled industrial engine of standard design and construction.

The engine rating shall be in accordance with ISO 3046 under the required site conditions.

The engine flywheel shall be suitable for the required starting duty.

Turbochargers shall be exhaust gas driven.

Engine governors shall be in accordance with BS 5514 Part 4 Class A2.

The unit shall be complete with a local control panel which shall be interfaced to the plant control system.

The fuel tank shall have a capacity of [eight] hours.

One cooling radiator shall be provided for the engine taking into account the engine duty.

One heat exchanger shall be provided for cooling the engine jacket water. The jacket water system shall be thermostatically controlled, with an engine driven circulating pump.

The lubricating oil system shall be self contained independent pressurized serving all the engine requirements.

Engines started using compressed air shall have one receiver per engine, and the system shall be sized for six starts.

It shall be possible to exercise the diesel. When exercising all engine protection, alarms and trips shall be operational. During exercising the load on the essential supplies/common switchboard shall be transferred to the diesel.

The generator shall be of the brushless type with Class 155 (F) insulation with temperature rises and total temperatures limited to Class 130 (B) limits.

Under black start conditions, and where there is more than one gas turbine, a gas turbine shall be selected for start. A coded key/electrical interlock shall ensure that only one gas turbine can

- 7.13 -


be started at any one time. The coded key/electrical interlock system shall encompass the MV circuit breaker which supplies the emergency transformer, ensuring that it will not be possible to start a gas turbine whilst the diesel is supplying the essential supplies/common switchboard and vice versa. The circuit breaker on the secondary side of the emergency transformer shall be interlocked to ensure that the emergency transformer cannot be paralleled with any other incoming supply to the essential supplies/common switchboard.

7.13 Metering

The tariff metering system shall include main and check meters. All meters shall be suitable for three phase imbalanced loads, be Class 0.2S, and shall comply with IEC 60687. The output from the meters shall be accessible from the plant control system. The metering system shall measure each generator output, and the import and export of the total power station active and reactive power.

7.14 Motors

Motors shall comply with the requirements of IEC 60034 and IEC 60072. All motors rated 100kW and above shall be fitted with winding temperature detectors. Motors rated 200kW and above shall be medium voltage.

Motor enclosures shall be IP54 for indoor applications and IP55 for outdoor applications, and shall be totally enclosed fan cooled.

Winding insulation shall be to Class 155 (F) with temperature rises and total temperatures restricted to Class 130 (B) limits.

All MV and outdoor motors shall be fitted with anti-condensation heaters.

Rolling element type bearings shall comply with ISO standards. Oil lubricated bearings shall be fitted with an accessible drain plug, and means of observing the oil flow.

Terminal boxes shall be totally enclosed to prevent the ingress of dust and moisture. The supply cable shall have a separate terminal box. LV motors shall have insulating barriers between terminals, MV motors shall have phase segregated terminals.

Materials for air coolers shall be selected to provide resistance to corrosion.

7.15 Earthing

A site survey shall be undertaken to determine the soil resistivity. Based on these results a study shall be carried out to determine the touch and step potentials of the new system, or extension to an existing system where applicable. The design and installation shall comply with IEEE 80, IEEE 665, IEEE 1050, BS 6739 and BS 7430. The maximum resistance of the grid shall be one ohm (1 Ω).

Connections to existing systems and substation earthing systems shall be made by disconnecting links readily accessible for test purposes.

- 7.14 -


All disconnecting links and distribution bars shall be supported from insulators.

Earthing distribution bars shall be strategically positioned around the plant areas.

All metallic casings, frames and tanks of electrical equipment shall be bonded to the earthing system, along with all structural steelwork, metallic fences and gates, and steel reinforcing. Connections to electrical equipment shall be detachable from the earthing bolt or stud. Cable trays and ladder racking shall be earthed at regular intervals.

Generator neutrals shall be connected through a resistor in order to limit the fault current to 10 A. Transformer windings with a star point shall be solidly earthed.

Switchboard earth bars shall be connected to the earthing system at each end of the equipment.

Dedicated earth bars and disconnecting links for electronic equipment shall be clearly identified.

The earthing system within buildings shall comply with BS 7671.

Pipelines entering the site shall be fitted with an insulated flange at the boundary. The minimum resistance across the flange shall be one thousand ohms (1 kΩ).

Conductors shall be stranded high conductivity copper to IEC 60228. Solid rods or bars shall be to BS EN 13601.

Where ground rods are used they shall be hard drawn high conductivity copper with hardened steel driving caps and tips.

7.16 Cabling

7.16.1 General

The cable installation shall be complete with all terminations, trays, ladder racks, glands, ferrules, lugs, markers, and fixings.

Cables shall be in one continuous length, have high conductivity copper conductors, and comply with IEC 60332-3.

Medium and low voltage power cables shall comply with IEC 60502 and IEC 60811.

The conductor cross section of each cable shall be adequate for carrying the prospective fault current determined by the next upstream short circuit protection device.

The voltage drop between the point of supply and the fixed equipment shall be limited to 4 per cent.

All power cables shall have phase identification.

- 7.15 -


Galvanized steel wire armour shall be used for multicore cables, aluminium wire armour for single core cables.

Single core power cables shall be earthed at one end only.

PVC sheathing shall have an oxygen index of not less than 30.

Building services wiring shall have XLPE insulation.

7.16.2 Medium voltage cables

All medium voltage cables shall be XLPE or EPR insulated with a LSF sheath.

7.16.3 Low voltage cables

All low voltage cables shall be XLPE insulated with a LSF sheath.

7.16.4 Control and instrumentation cables

All multicore control cables shall have approximately 20 per cent spare cores, but not less than two cores for future use. All cores shall be PVC or XLPE insulated, and numbered throughout their length. Individually screened twisted pairs or overall screened multicore cables shall be provided for control and instrumentation cables.

7.16.5 Optical fibre cables

All fibre optic cables shall comply with IEC 60794, and have Aramid type strain relief elements. The cables shall be able to operate continuously in temperatures between –10°C and +60°C.

The fibre optic cables shall be loose tube type, with the fibres fed into tubes. The tubes shall be sufficiently strong to hold their shape and provide protection for the fibres against deformation and friction. Each tube shall be colour coded.

Where fibre optic cables are to be laid in contaminated ground, a water repellent gel filling and a moisture barrier shall be applied longitudinally over the cores to ensure long term water tightness. An inner polyethylene sheath shall contain a hydrogen scavenger to eliminate the risk of hydrogen build up around the fibres during operation.

Fibre optic cables which are direct buried shall be armoured.

7.16.6 Telephone cables

All telephone cables shall have a minimum of two pairs of tinned solid copper conductors. The minimum conductor diameter shall be 0.5mm. All telephone cables shall have colour coded core insulation.

The insulation and outer sheath of telephone cables for internal use shall be halogen free. Cables with more than six pairs shall have a fire barrier tape.

- 7.16 -


All telephone cables for external use shall have cores embedded in a water repellent gel to prevent the ingress of moisture, and an outer sheath of tough UV resistant polyethylene.

Telephone cables which are direct buried shall be armoured.

7.16.7 High temperature cables

Silicon insulated cables shall be used for applications such as alarms, lighting, and essential services in temperatures between –60°C up to 180°C. Stranded conductors shall be to BS 6360/VDE 0295 Class 5. A glass fibre braid shall be applied over the silicon insulation, with a silicon outer sheath. Where mechanical protection is required, a glass fibre tape shall be applied over the silicon sheath with an outer galvanized steel wire braid.

7.16.8 Intrinsically safe cables

Cables used for intrinsically safe circuits shall have a blue outer sheath in accordance with BS EN 60079-14. No other cables shall be supplied with a blue outer sheath.

7.16.9 Mineral insulated cables

Mineral insulated (MI) cables shall have copper conductors surrounded by a compressed mineral insulant with a copper sheath and a halogen free LSF outer sheath.

7.16.10 Cable installation

All cables shall be laid in preformed trenches, direct in ground, in ducts, and supported on racks and trays.

Buried unarmoured cables shall be mechanically protected throughout by ducts encased in concrete.

Cable trays, ladder racks and supports shall generally be heavy duty galvanized mild steel. Stainless steel or GRP shall be used in saline atmospheres.

To enable complete redundancy to be maintained, two separate routes shall be used for the data highway.

The cabling systems of each unit shall be physically separated, or segregated by fire barriers with a minimum of 1 hour fire resistance.

Preformed trenches shall be of adequate size to allow for cable trays or ladder racks to be installed on the side of the trenches. The trenches shall be complete with concrete covers.

Cables laid direct in the ground shall be covered with a layer of sand, with protective tiles above the sand. Tape shall be laid above the tiles to indicate the presence of cables below.

Drawpits shall be positioned at reasonable intervals in long runs and changes of direction of cable ducts.

- 7.17 -


Cables rising out of a duct or the ground shall be protected for a minimum of 1.5 m above the finished floor level.

Cables with a diameter of 15 mm or less shall be supported on cable trays. Ladder rack shall be used for cables with a diameter larger than 15 mm.

Control cables shall not be run on the same tray or ladder as power cables.

Single core cables run in trefoil shall be cleated using non magnetic trefoil cleats which shall be capable of withstanding the forces produced under short circuit conditions.

Steel cable ties shall be used for vertical runs of cable. PVC and nylon tie wraps shall not be used on horizontal runs which are in direct sunlight.

PVC shrouds shall be provided over all cable glands.

Cable lugs shall be the compression type.

Covers shall be provided for trays and ladder rack where the cables are in direct sunlight.

Cores of all control cables shall be long enough to allow a second termination at a future date.

Screens on multicore cables shall be insulated from field instruments and cable armour and shall be connected to ensure continuity throughout their length.

All cables and cable cores shall be unambiguously identified.

All MI cable terminations shall be complete with pot type seals, cold compound, glands, and high temperature neoprene sleeves.

Wiring ferrules shall be suitable for affixing to the cable cores.

All steel conduit along with all accessories and fixings shall comply with IEC 60423 and IEC 60614. Minimum conduit size shall be 20 mm2. Conduit shall be hot dip galvanized, fittings shall be galvanized malleable iron.

All ducts and conduits shall have their ends sealed against the ingress of water and oil.

Conduits and ducts shall be sized to enable the cables to be easily drawn in.

Cable trunking shall be manufactured from galvanized mild steel. The coating shall comply with ISO 1461.

The trunking shall be provided with removable covers.

Copper bonding links shall be fitted across all trunking joints.

- 7.18 -


Where cables pass horizontally through walls or vertically through floors and ceilings non-combustible, non-metallic fire barriers shall be installed.

7.17 Static frequency converter

The static frequency converter shall be controlled by the plant control system. Local control shall be provided for maintenance purposes. The converter shall also be complete with all accessories necessary for remote, manual, and testing operations. The SFC shall be a variable frequency solid state 12 pulse width modulated adjustable speed converter housed in an IP41 enclosure.

7.18 Electrical equipment for hazardous areas

The installation design, and the manufacture, certification and installation of electrical equipment in hazardous areas shall comply with IEC 60079. All hazardous areas shall be shown on site layout drawings.

- 8.1 -


8. CONTROL, INSTRUMENTATION AND COMMUNICATIONS

8.1 Introduction

This Section describes the technical requirements for the supply and installation of control and instrumentation (C&I) for the gas turbine power plant. All C&I equipment necessary to allow the safe and efficient operation of the power plant shall be supplied, installed, commissioned and tested.

A consistent control, instrumentation and data acquisition philosophy shall be applied throughout the power plant. The objective shall be to standardize all equipment, wherever possible, throughout the power plant in order to rationalize operation, maintenance and reduce spare parts. In general, all equipment shall be of modern compact design, incorporating proven technology and supplied from one composite range as marketed by a reputable international manufacturer.

C&I shall be provided such that no single failure can cause a forced outage of the power plant. Triple modular redundant control systems (2 out of 3 voting) shall be provided for all plant safety critical control and protection systems.

8.2 Scope of supply

The extent of supply described shall be the minimum necessary to achieve the required objectives and shall consist of, as a minimum, the following:

a. Complete control, protection and monitoring systems for the plant being provided including the gas turbine generator and its auxiliary equipment plus balance of plant.

b. Local control rooms to primarily house the control and monitoring equipment associated with the gas turbine and its auxiliaries and provide the local operating point for each machine.

c. Plant Control System including all hardware, software, operating licences and associated equipment to provide integrated control and monitoring of the overall plant from the central control room.

d. Central control room equipment including operator desks, chairs, printers, furniture, etc.

e. Emergency shutdown systems for safe plant running, shut-down and protection.

f. Interfaces between the Plant Control System, field equipment, packaged control systems, instrumentation, actuators, motor control centres and all associated equipment and devices.

g. Interfaces to the load dispatch centre and station administration LAN.

h. Condition monitoring equipment for the gas turbines.

i. All C&I and telecommunication cabling systems.

- 8.2 -


j. Plant performance monitoring equipment.

k. Instrumentation with accuracy suitable for tariff metering of fuel supplies and electricity generated with display, trending and log reports of current and cumulative values.

l. Air and water emissions monitoring equipment.

m. Local instrumentation, including pressure, temperature, level and flow gauges, switches, transducers and transmitters, and all associated tapping points, pipe work, valves, thermowells, local cubicles and racks.

n. Uninterruptible power supplies

o. Telecommunication systems.

p. Plant control system clock system.

q. Closed circuit television (CCTV) and perimeter security systems.

r. Weather station.

s. Fire and gas detection and protection systems.

t. Factory and Site testing and inspection.

u. Site erection, installation and commissioning.

v. Operating and maintenance manuals, including as-built information.

w. Operator and maintenance staff training.

x. Spare parts (commissioning spares and two years operating spares).

y. Special tools and equipment.

8.3 Objectives

The main objectives of the C&I scheme are as follows:

a. To allow safe start-up, synchronizing, shut-down, emergency tripping, control and monitoring of all major plant areas.

b. To allow the optimized and efficient use of all plant areas.

c. To maximize the availability of all plant.

d. To incorporate a maximum level of automatic control, thereby minimizing operator manning levels, and incorporating “one-button” start-up and synchronizing, and “one-button” shut-down where appropriate.

- 8.3 -


e. To provide facilities for comprehensive monitoring, storage and presentation of information concerning plant conditions.

f. To provide facilities for comprehensive testing and presentation of information concerning system and plant performance.

g. To centralize plant monitoring and control facilities.

h. To reduce start-up and shut-down sequence times to a minimum whilst minimizing mechanical and thermal stresses imposed on the plant.

8.4 Operational philosophy

The Plant Control System shall consist of a set of microprocessor-based controllers interconnected via a suitable communications network to allow the interchange of data and control commands. The controllers shall be capable of performing data acquisition, logic, sequential and closed loop control utilizing real time data derived from plant-mounted instrumentation. Control commands shall be issued by the Plant Control System to actuators and final drives located on the plant. The controllers shall be functionally distributed and physically located in suitable plant areas, particular care being taken to ensure that the equipment is suitable for the proposed environment.

The control system configuration and associated real time data shall be resident in the system database that shall be either distributed throughout the controllers or resident in a server but accessible to all controllers and operator devices.

The network shall also communicate with the Human Machine Interface (HMI) to allow centralized monitoring and operator control of the plant from the Central Control Room. This shall be based on the use of visual display units (VDUs), keyboards and other inputting devices.

The Plant Control System shall be capable of providing control of individual drives, of sequencing a functional group of drives to an optimized program of plant operation, and of sequencing functional groups to provide full automatic plant operation, (eg one-button” start-up).

The Plant Control System shall incorporate functions for use by the operating, engineering and management staff including, but not limited to, data historian, event and alarm handling, engineering and diagnostic tools, software configuration tools, plant condition monitoring and performance monitoring.

Main items of plant such as the gas turbine, fuel systems, water treatment plant, etc may be supplied with purpose-designed systems for control, monitoring and protection. Such systems shall be designed to function independently of each other but shall be interfaced with the Plant Control System to allow integrated operation of the total plant. The Plant Control System shall be fully integrated with the control, instrumentation and alarm equipment of the plant being provided, in order to maximize automation of the power plant and minimize operator manning levels.

The Plant Control System shall incorporate a high level of availability and be designed such that a single component failure shall not result in the shut down of any plant or the reduction in plant load. This shall be achieved by the equipment and component design and the provision of dual redundant power supplies, control processors and data communications equipment. Where

- 8.4 -


applicable dual redundant input/output devices shall also be provided. Gas turbine protection shall be achieved by dedicated systems utilizing triplicated I/O channels and 2-out-of-3 voting logic. For all other plant safety critical protection systems the redundancy provided shall be in compliance with the required safety integrity level.

The Plant Control System shall be supplemented by local controls and instruments necessary for maintenance and commissioning activities and for performance testing of the plant. The Plant Control System and local controls shall be designed such that it shall not be possible to operate any item of plant from more than one point of control simultaneously.

8.5 Control and monitoring of plant

8.5.1 Gas turbine

A comprehensive control, instrumentation and alarm equipment package shall be provided for the gas turbine generator. This shall include the automatic control, monitoring and protection systems necessary for the safe and efficient operation of the gas turbine, generator and all auxiliary equipment. The controls shall enable the gas turbine generator to meet the optimum output achievable under steady state and changing load conditions while maintaining safe conditions and high levels of efficiency. The control and instrumentation package shall be integrated with the Plant Control System via a dual redundant serial data communications link to allow normal operation and supervision of the gas turbine generator and auxiliary equipment remotely from the CCR. In the event of a failure in the communications to the Plant Control System, the gas turbine control package shall continue to operate normally.

The extent of hardwiring of critical signals between the GT and the Plant Control System shall be subject to approval.

The control and instrumentation shall include, but not be limited to, the following:

a. Redundant automatic turbine governor controls

b. Redundant emergency tripping and protection systems.

c. Sequence controls and interlocks (eg pre-start checks, start-up, shut-down, etc).

d. Machine condition monitoring and turbine supervisory equipment.

e. C&I for auxiliary systems, providing local and remote indications of mechanical and electrical quantities as required.

f. Local and remote indication of control and isolating valve positions, motor loads and status of main auxiliaries.

g. Local and remote alarms.

h. Generator controls and instrumentation

i. NOx control system and associated instrumentation

- 8.5 -


j. Fire and gas detection systems

k. Emissions monitoring equipment.

Control processors and instrumentation shall be provided such that no single failure can cause a forced outage. To this end dual redundant and triple modular voting systems shall be used as appropriate throughout the control and instrumentation system design.

Local control panel(s) shall be provided for the gas turbine and auxiliary equipment to house controls, indications and associated equipment. Controls and a Human Machine Interface (HMI) shall be provided at the panel(s) to allow starting, stopping and emergency tripping of the GT and auxiliaries. There shall be the facility to select local control or control from the CCR via the Plant Control System. The local control panel(s) shall be mounted together with the associated motor control equipment within a purpose built air-conditioned enclosure adjacent to the gas turbine.

8.5.2 Auxiliary plant

Unless otherwise specified, the manufacturers’ standard packages of control and instrumentation shall be supplied for all auxiliary plant. Protection systems shall be independent of the control system for that plant. Equipment shall be supplied to interface all auxiliary plant with the Plant Control System to enable normal control and supervision of the plant remotely from the CCR. This shall be supplemented with local controls, gauges and other devices to allow local maintenance and testing activities where required. The control and instrumentation systems for the common systems shall be designed, manufactured and installed to the same standards as that provided for the main plant.

Complete control, instrumentation and protection packages shall be provided where applicable for all systems provided under the contract. This shall include but not be limited to:

a. Water systems (eg cooling water, service water and demineralized water)

b. Compressed air systems (eg instrument and service air)

c. Fire Detection and Protection systems.

d. Gas detection equipment.

e. Fuel systems (eg oil and gas fuel processing and storage systems).

f. Heating and ventilation systems.

g. Black start/emergency diesel generator.

h. Emission monitoring systems.

8.5.3 Generator

Comprehensive control, instrumentation and alarm equipment, including automatic control systems necessary for the safe and efficient operation of each electrical generator shall be supplied.

- 8.6 -


These shall be integrated with the Plant Control System for remote operation and supervision from the CCR.

The controls shall enable the generator to meet the optimum output achievable under steady state and changing load conditions while maintaining safe conditions and high levels of efficiency.

The control and instrumentation shall include, but not be limited to, the following:

a. Automatic controls and associated equipment.

b. Emergency tripping and protection systems.

c. Sequence controls and interlocks (eg synchronizing, shut-down, etc).

d. Local and remote alarms.

e. Generator C&I, including generator excitation and synchronizing equipment.

8.5.4 Electrical distribution system

All incoming and outgoing feeders, main electrical switchboards, sub-boards and feeds to main plant auxiliaries shall be monitored and controlled at the CCR. The status and data associated with the electrical distribution system shall be displayed in the CCR via the Plant Control System and shall include all systems down to a voltage level of 400 V.

The controls and indications shall include, but not be limited to, the following:

a. Status of circuit breakers, isolators, bus couplers and earth switches on switchboards, including incoming feeders, feeds to main auxiliaries and feeds to sub-boards.

b. Alarms associated with circuit breakers, isolators, bus couplers, earth switches, transformers and electrical protection equipment.

c. Transformer tap positions.

d. Power (MW), reactive power (MVAr), current (A), frequency (Hz) and volt (kV) exported/imported from/to the site.

e. Frequency (Hz), current (A) and voltage (kV) for each main board

f. Power (MW), reactive power (MVAr), current (A), frequency (Hz), voltage (kV) and power factor (PF) for each generating unit

All equipment shall be provided to achieve the necessary level of monitoring, including current and voltage transformers, transducers, auxiliary contacts, marshalling and termination facilities and cabling.

- 8.7 -


Suitable interfaces to the Plant Control System shall be incorporated into the switchgear. Remote operation of selected switchgear shall be by use of the Plant Control System .

Remote closure of generator main circuit breakers shall be by automatic synchronizer which shall be initiated locally or from the CCR via the Plant Control System. This shall be selectable locally to the appropriate generator. Remote opening of generator main circuit breaker shall be by trip protection circuits.

8.6 Plant control system

8.6.1 General system design

A fully integrated Plant Control System shall be provided to monitor, control, display, alarm and record selected physical and electrical parameters associated with all plant areas.

Where appropriate, the system shall have a functionally and geographically distributed architecture utilizing a number of independent outstations or nodes containing control processors, power supplies, data communications systems, marshalling and termination facilities. The Outstations shall be capable of autonomous operation and perform data acquisition, calculation, open loop, and closed-loop control functions. Communications between the nodes located in different plant areas and the Operator's or Engineer's Workstations located in the Central Control Room shall be performed over suitably designed, redundant high-speed serial data highways. The communications system shall be designed to perform at the speed necessary to ensure that all variables are updated and control commands are issued without loss of system performance. The communications system shall include all control equipment, error detection correction facilities and cabling.

The Plant Control System shall be designed to ensure maximum availability by the inclusion of built-in redundancy for both hardware and software. This shall include duplicated control processors, data highway and power supplies with automatic changeover to the standby unit upon detection of a fault or failure of the operating unit. Where appropriate, I/O cards shall also be duplicated. The failure of any single element shall not affect the operation of any item of operating plant. In particular, the duplicated control processors shall be capable of fail over without change to plant status, sequence status or control actions, at any stage of plant operation.

A PCS configuration drawing showing the basic HMI and interfaces to the plant and other users is included in Volume 3 Drawings. The Contractor shall be responsible for ensuring that the functional requirements stated in the specification are implemented.

The Plant Control System shall be designed to have an availability of 99.98 per cent or better by the inclusion of built-in redundancy for both hardware and software. This shall include redundant control processors, data highways and power supplies with automatic changeover to the standby unit upon detection of a fault or failure of the operating unit. Redundancy is required for all input and output modules used for safety critical control or protection functions. The failure of any single element within the PCS shall not affect the operation of any item of operating plant.

Comprehensive system diagnostics shall be incorporated to assist in maintenance and trouble-shooting. These shall include memory, control processors, I/O cards, data highway, and storage devices as a minimum.

- 8.8 -


The Plant Control System shall be synchronized to the plant master clock system.

All necessary hardware for marshalling and terminating incoming and outgoing plant cabling shall be provided. This shall include gland plates, glands, terminal blocks, intrinsic safety barriers, isolation devices, labelling and wiring. Equipment shall be designed to operate in hazardous areas where necessary.

8.6.2 Operator’s facilities

Operator’s workstations shall be provided in the Central Control Room (CCR) to allow monitoring, control and adjustment of plant conditions via high resolution “Windows” style graphics displays. All visual display units (VDUs), keyboards, printers, peripheral devices, and their associated control desks shall be supplied. Each operator workstation shall be arranged for an operator to monitor and control each GT, their auxiliaries, the common auxiliary plant and the electrical systems.

The CCR shall contain a minimum of two operator workstations and one Engineering Workstation. Each operator workstation shall consist of at least two high resolution colour 21” VDUs, a single keyboard and a cursor positioning device. The resolution of the VDUs shall be 1280 x 1024 pixels or better. The workstations shall have the capability of being configured as either an Operator’s workstation or an Engineer’s workstation through different passwords and shall be the main facility for monitoring and controlling the whole plant.

The CCR control desks shall be of a co-ordinated rigid design and of robust construction. Surfaces suitable for mounting the VDUs, keyboards, telephones and all other devices shall be included in the design. The control desks shall be ergonomically arranged, suitable for operation by the minimum number of operators and consistent with the plant operating philosophy. Access must be possible by more than one operator in the event of special operations and for training purposes.

The control desks shall include in their construction, facilities in the desk top and the base of the units to route cables from VDUs, keyboards, telephones, etc. Lockable drawer/storage space, levelling and fixing devices shall be incorporated into the design. A suitable number of fully adjustable swivel chairs shall be provided (as a guide, a minimum of one chair per workstation plus one additional chair shall be provided) together with all necessary CCR furniture.

The Contractor shall provide with his bid submission, a drawing showing the proposed layout and locations of equipment within the CCR and the associated equipment rooms.

8.6.3 Engineer’s workstation

One Engineer’s Workstations (EWS) shall be provided for fault finding and software programming. All necessary hardware and software shall be provided to allow engineering staff to trace faults in the system and applications software, to create control strategies, VDU screens and all other maintenance activities. Software configuration and modification shall be done off-line and with the capability for testing before downloading to the control processors.

The EWS shall consist of a high resolution VDU, keyboard, input device (eg mouse, trackball etc) mounted on a suitable desk matching the Operator‘s Workstation in appearance. A colour laser printer shall also be provided. The EWS shall be connected to the Plant Control System

- 8.9 -


via a data highway to allow access to system and applications software and to live plant data. Access shall be password protected.

8.6.4 System response times

The response times for the Operator’s Workstations under normal conditions shall be as follows:

a. The time between selection and display of a VDU, fully updated, from the database shall not exceed 2 seconds with a typical workstation loading.

b. The time between execution of a control function on an Operator’s workstation and the command reaching the output termination’s of the outstation shall not exceed 2 seconds.

c. The time between the occurrence or change of a signal at the origin and the change of state, value or alarm showing on the VDU shall not exceed 2 seconds.

8.6.5 Spare capacity

The Plant Control System shall be supplied with all hardware, system and applications software (VDU displays, alarms, etc) fully developed, tested, debugged and installed for all analogue and digital I/O’s. An overall further 20 per cent spare equipment shall be provided including all necessary hardware and associated wiring, supplied and tested. Software shall be designed so as to ensure no degradation in the specified performance with the system fully loaded including the spare capacity.

8.6.6 Software

8.6.6.1 General

The latest version of the manufacture’s operating system software shall be provided fully developed, tested and installed.

The application software and associated displays, reports, databases, etc, shall be configured and fully tested when installed at site. The creation or modification of displays, reports, databases or control strategies shall be possible with the system on-line by the Owner’s engineering personnel without affecting the plant operation. Modifications to the software shall be done in straightforward and logical steps using, wherever possible, graphic displays. It shall not be necessary to have specialist knowledge of the underlying software in order to carry out modifications.

All necessary software licences shall be included. This shall allow unrestricted use of all specified software packages by the Owner.

Access to software and application programmes at various levels shall be possible by operating or engineering personnel using passwords. This shall protect the software from unauthorized access. Any changes to software, either application and/or operating, shall be fully documented in a logical and structured manner in such a way that the history and nature of the changes can be easily identified.

- 8.10 -


8.6.6.2 Operator interface software

The operator interface software shall enable the Operator to carry out the necessary actions in a safe and efficient manner. In particular the following features shall be included, as a minimum, but not be limited to:

a. Software shall be structured in such a way so as to provide a hierarchy of control from automatic sequential plant start-up through to manual control of an individual item.

b. During manual intervention by the Operator (sequence initiation and individual device control under normal and failure conditions), all software derived, hardwired permissive and overrides shall be visible to the Operator.

c. Where process measurements have been duplicated for improved reliability, the signals shall automatically switch to the good signal in the event of a fault. The Operator should have, for the purposes of maintenance, the on-screen facility to select either signal or the average, as the measured variable for control.

A philosophy shall be developed to define the action of the sequence logic in the event of a step failure, Operator intervention or the initiation of a sequence with not all plant conditions satisfied. It shall be possible to bypass a required plant condition but this action shall be alarmed and logged. The philosophy of operation shall be to the Owner’s approval.

8.6.6.3 Reports

The Plant Control System shall be capable of presenting to the Operator, pre-defined reports. The information on the reports may be either in tabular form or in a pre-formatted report form and may be automatic at specific times or on request. Reports shall include periodic logs, daily logs and group logs, balance of energy and efficiency log. In addition reports shall be produced to meet the requirements of the Environment Agency. All reports shall be configured and report formats shall be to the approval of the Owner. The facility for the operator to generate specific reports as required shall also be provided.

8.6.6.4 Alarm management

All plant and system generated alarms shall be prioritized, logged and displayed by the Plant Control System. There shall be a dedicated alarm display, which shall show all the plant alarms or groups of alarms. The Operator’s attention shall be drawn to the occurrence of an alarm by a suitable audible and visual alarm at the CCR desk. Alarms shall also be printed on the alarm/event printer.

The Operator shall have the facility to select optional alarm displays, summary of alarms, historical alarms on global or point based, unacknowledged alarms, alarms by priority, alarms by pre-defined system groups.

There shall be a facility to suppress an alarm or groups of alarms as a result of a particular alarm or other plant condition in order to minimize the number of alarms under transient conditions.

- 8.11 -


All alarms generated from either analogue or digital I/O shall be configured with an adjustable dead band. The value of the dead band shall form part of the configuration software.

8.6.6.5 Data logging and trends

The Plant Control System shall incorporate long term data logging facilities for all analogue, digital, serial data, alarms, condition monitoring and other internally generated points including the overall extension capacity specified. Data shall be stored for up to 12 months on a suitable storage medium and an alarm generated to inform the Operator when the storage medium approaches 75 per cent of its maximum capacity. All data shall be automatically archived and retained for future reference in either optical or magnetic medium.

The operator shall have the facility to display real time data, recall data held in the data logger memory or from archives over a specified period of time. The requested information may be displayed on the Operator’s workstations either in tabular form or as selected variables on a trend display. It shall be possible to compare on the same display, multiple trends of real-time data or historical data from the data logger or archives.

The format and content of the reports for data retrieval from the logging facility shall be subject to approval by the Owner.

8.6.6.6 Sequence of events

A sequence of events (SOE) recording system shall be supplied to allow analysis of the causes of trips or plant disturbances. The SOE recorder may be either integrated within the Plant Control System (preferred method) or a standalone item of equipment. The SOE recorder shall scan all agreed binary inputs continuously with a resolution of 1 ms.

The status of each point shall be time tagged and stored in a database together with other relevant information for a specific time period. Data will be continuously deleted from the database on a first-in, first-out basis after the specified time period has elapsed. Facilities shall be provided for the data to be archived for future reference, and for easy retrieval for viewing and analysis.

On the occurrence of a nominated event eg turbine trip or manual initiation from the PCS, all data for a specified time period before the event shall be retained and continue to be recorded for a period after the event.

The SOE recorder shall automatically reset after the elapsed time period and continue to monitor the Plant in the normal way.

SOE reports shall be generated and printed using the stored data and shall be used for post trip review and analysis. The report shall be presented in a clear and logical format and clearly indicate the “first cause” of the event.

- 8.12 -


8.7 Metering

Metering shall be provided for process control, performance monitoring and emissions monitoring. Data shall be derived from plant instruments designed and installed to measure actual values and shall be corrected where necessary for variations in pressure, temperature, density etc.

All measurements shall be displayed locally and monitored, displayed and logged by the Plant Control System. Facilities shall also be provided for integrating the instantaneous values over a pre-defined time period.

Metering shall be supplied to include but not be limited to the following:

a. Volumetric, mass and energy flow of fuel onto site and to each GT.

b. Raw water flow.

c. Electrical power (active and reactive) from each generator.

d. Total electrical power (active and reactive) imported and exported from/to the Grid.

e. Effluent discharge flow.

8.8 Uninterruptible power supply

Suitable uninterruptible power supplies (UPS), with 100 per cent redundancy, shall be provided. The UPS shall be provided to support the PCS and other control/protection systems in the event of a power failure. The system shall be designed to provide electrical noise free power for a minimum of 4 hours continuously.

In general, each UPS shall consist of the following components:

a. 3-phase rectifier/battery charger unit.

b. 1 or 3-phase static inverter.

c. 1 or 3-phase static by-pass isolators.

d. Sealed lead acid batteries.

The UPS shall automatically support the total load presented by the PCS and other control/protection and safety systems equipment on mains failure without a break in supply. Alarms shall be displayed on the alarm fascia in the event of a mains failure or of a fault in the UPS as well as on the PCS. Reinstatement of normal supplies shall be effected automatically without the need for re-programming or operator intervention. Each UPS shall be supplied with a comprehensive battery monitor which shall alert the operator to any problems. No single failure in the UPS or the equipment it supplies shall cause a plant shutdown.

- 8.13 -


For maintenance purposes an independent manual by-pass switch shall be provided to allow the PCS to be powered from an alternative source. This shall allow maintenance procedures to be carried out safely and without interruption to the system operation.

Where hydrogen is generated the correct precautions of a hazardous zone shall be taken.

The UPS shall be rated at 125 per cent of full load. The stand alone time at rated output plus 125 per cent for 10 minutes and 150 per cent for 1 minute, shall be not less than 4 hours.

The UPS shall be suitable for operation with an input voltage variation of ±10 per cent and a frequency variation of ±5 per cent.

8.9 Condition monitoring

Comprehensive condition monitoring facilities shall be provided for the gas turbine generators. All necessary hardware and software shall be provided including field transducers, processing equipment, cabling, computer, printer and software package.

The system shall be designed to monitor, display and record specific parameters associated with the general mechanical condition of the plant such as vibration, bearing temperatures, winding temperatures etc. The software package shall be designed to highlight deterioration in the condition of the plant by assessing the changing trends in the plant parameters. The software shall also take into account external influences on the plant (eg number of starts, hours run etc) and raise an alarm when limits are approached or are about to be exceeded.

The measured parameters shall be recorded and made available for analysis at a later date and for archiving purposes. Recall of the data shall be available either in tabular or graphical (trend) display form. Suitable hardware and software shall be provided for this purpose.

The condition monitoring system shall be provided fully configured and operational.

8.10 Plant performance monitoring

Facilities shall be provided to enable the performance of the plant to be continually monitored based on real time data derived from the Plant Control System. The equipment shall consist of a suitable desk-top PC and printer running software designed to calculate, display and report on the performance of the overall plant and specific plant areas. The system shall generate reports for analysis by management, engineering and operating staff identifying specific plant values such as MW, MVAr, fuel usage, etc and calculated values such as heat rate, efficiencies etc.

The facility shall be computer-based and shall include all necessary hardware, software, data-inputting and interconnection with other plant equipment to form a complete and working system. It shall utilize real-time data derived directly from the Plant Control System via suitable data communications medium and shall employ non-linear optimization techniques.

Additional facilities shall be provided to allow operating, engineering and management staff to carry out on-line and off-line optimization of the power plant. Use of this facility shall not

- 8.14 -


directly affect the operation or control of the power station. The optimizer shall be complete with its own printer for generating reports, data schedules, diagrams etc as required.

8.11 Emissions monitoring

Continuous emission monitoring equipment shall be provided to monitor the plant stack emissions and waste water discharged from the site.

Indication and recording of the corrected concentrations of gases in the stack shall include, as a minimum:

a. Flue gas O2

b. Flue gas CO

c. Flue gas SO2

d. Flue gas NOx

e. Flue gas opacity (dust)

Chlorine and halogen residuals shall also be monitored in the water sent to waste after treatment. The flow, temperature and pH levels of the wastewater shall be continuously monitored and displayed by the PCS. Alarm levels shall be presented to the operator for action.

The instruments for stack and water discharges shall be complete and shall display the instantaneous value of the measurements to the operator in the CCR via the PCS. Local indication shall also be provided for each measurement at the respective measuring meter. Fault alarms for each instrument shall be raised in the CCR.

The measurements shall be displayed by the instruments in a format suitable for submission to the appropriate environmental agency. The PCS shall display and record the measurements in the same way. All measurements shall be compensated, where necessary, for variations in temperature, atmospheric pressure, humidity etc and the correcting values made available for display by the PCS.

The Plant Control System shall be capable of performing hourly and daily averages for all measurements and give early warning alarms of measurements approaching their maximum limits.

The equipment shall be of proven reliability and shall be subject to the approval of the Owner. Details of other sites where the equipment has been installed shall be provided.

8.12 Station clock system

A station clock system shall be provided to synchronize the Plant Control System and other plant control systems, for the purposes of synchronizing data acquisition, data logging, alarm and trip events, etc, for all systems employed in such a manner on the site.

- 8.15 -


The station clock will be set from an appropriate radio time signal (eg GPS signal). The system will be capable of monitoring the grid system time, and display to the Operator in the CCR, the time difference and GMT.

The equipment shall be supplied with sufficient outputs of the correct type to meet the operating requirements of the plant. Station clocks synchronized to the system, shall be supplied and installed in locations to be approved during the detailed design stage.

8.13 Load dispatch

A communications interface for the transfer of data to and from a central load dispatch facility shall be provide within the PCS.

8.14 Fire detection and alarm system

A comprehensive fire detection and alarm system shall be provided to cover all equipment on site that could constitute a fire risk. The system shall be designed and installed in accordance requirements of NFPA and shall in addition comply with any requirements of the relevant Iraq Authority. All necessary hardware, software, fire detectors, manual call points, local alarm panels, remote alarm panels, cabling, electronic sounders, beacons and interface to the Plant Control System shall be provided.

The following alarm facilities, including initiation devices, shall be provided:

a. both local and remote audible and visual indication of the operation of any water spray protection or foam protection system;

b. both local and remote audible and visual indication of the operation of any building or plant area fire detection system;

c. both local and remote audible and visual indication of the operation of the gas turbine enclosure fire extinguishing system;

d. local and remote audible and visual indication of the operation of any manual break glass alarm switch;

e. Remote, audible and visual indication of status and fault condition of each fire pump.

Smoke detectors of the photoelectric type and heat detectors shall be suitably located to detect and provide early warning of fire risks. All detectors shall be suitable for the specific areas in which they are located and particular attention shall be paid to ensure that airborne dust does not affect the correct operation of the detection equipment. On detection of fire both visual and audible alarms shall be provided locally and remotely in the CCR.

All detection circuits shall be monitored against open/short circuits. Should a malfunction occur in any circuit, this shall result in a fault condition on this detection zone, while all other zones shall continue to operate normally.

- 8.16 -


Manually operated break glass alarm switches shall be provided for mounting at selected positions throughout the plant, and buildings. All call points shall be provided with a key test facility to allow for testing of the system without dismantling or breaking the glass.

The fire fighting system shall be connected to the building services control system to shut down forced ventilation in the event of a fire.

Where required, local alarm and indicator panels shall be provided and mounted in approved locations adjacent to the areas being protected. The remote alarms and indicators covering all sections of the plant, together with spare ways, shall be mounted on the main fire alarms panel in the main control room.

8.15 Gas detection system

A gas detection monitoring system shall be provided to monitor and alarm the occurrence of fuel gas leaks in the fuel gas supply system and in the area of the gas turbines. Gas detectors shall be suitably located to detect all leaks and the possible build up of gases in enclosed areas. All necessary hardware and software, detectors, lamps, sirens, processing equipment, local cubicles, cabling and calibration tools/equipment shall be provided.

The gas detection monitoring system shall be designed for automatic and continuous monitoring of combustible gases using catalytic combustion or infrared principles. The system shall be intrinsically safe and to approved international standards. Each gas detection loop shall generate alarms at the local cubicles and PCS for both the lower and upper explosive limits.

The gas detection monitoring system shall be microprocessor based providing self-test and diagnostics facilities. A redundant serial communication link shall be provided to the PCS allowing display of gas concentrations, warnings, alarms and system fault conditions. Redundant hardwire signals for gas turbine trip on detection of high gas levels at the gas turbine shall be triplicated and configured to give a 2 out of 3 voting system.

8.16 Private automatic branch exchange (PABX)

An integrated services digital network (ISDN) type PABX, approved for connection to the public switched telephone network (PSTN) shall be provided for the power plant. The Contractor shall specify the initial installed capacity including numbers of exchange lines, tie lines and extension lines. A personal computer (PC) based telecommunication console shall be provided together with a VDU, keyboard and headset. The exchange shall be capable of future expansion. The Contractor shall specify the ultimate expansion capacity which shall be to approval.

The interconnecting cable between the PABX and the PSTN shall be the responsibility of others but the Contractor shall provide all facilities for the connection of this service including ducting within the building where the telephone exchange is located. All other internal telephone connections within the power station boundary, including cabling to and within the administration, control and turbine area, etc, shall be the responsibility of the Contractor.

The telephone system shall be powered via a battery/charger system to maintain the PABX and the PA system in normal operation for a period of not less than 10 hours in the event of a

- 8.17 -


failure of battery charging current, when the exchange has been fully extended. The batteries shall normally be kept charged by a dual battery charger unit, each charger comprising a float charger with manual boost charge facilities with capacity sufficient to cater for ultimate extension facility referred to previously. Each battery charger shall be housed in a separate robust and well constructed cubicle with good access to all components and equipment. It shall not be possible for the load to become disconnected from both batteries and chargers simultaneously.

The PABX system shall incorporate a self-surveillance facility for monitoring the status of the PABX equipment and appropriate alarms shall be raised automatically to alert the operator when a fault is detected in the system.

Telephone instruments shall be provided for all equipped circuits. These instruments shall be provided to suit the use and location and shall include basic wall and desk mounted units, executive handsets (with secretary and hands free facilities), background noise suppressed units with acoustic hoods for noisy plant areas and weatherproof units for external areas.

8.17 Public address system

A PA system shall be provided for the broadcast of announcements throughout the station. Loudspeakers shall be connected on a zonal basis with the call station and zone selection facilities located in the CCR.

The sound output level of the PA system shall be designed to achieve a sound pressure level 10 dB higher than the ambient noise in the area to ensure speech intelligibility. Loudspeakers shall be supplied suitable for the environmental conditions and be positioned and oriented to give the required sound coverage.

The PA system shall incorporate a self-surveillance facility for monitoring the status of the PA equipment including loudspeakers. Appropriate alarms shall be raised automatically to alert the operator when a fault is detected in the system.

8.18 Closed circuit television, intruder detection and site access control systems

A closed circuit television (CCTV) system shall be provided for the surveillance of the perimeter fence and gates. Fixed position cameras with fixed focal length lenses and pan-tilt-zoom (PTZ) cameras shall be employed to give the necessary coverage. The camera systems shall be digital based systems which shall be user configurable, scaleable, utilize digital storage devices and be implemented via large area networks.

The Contractor shall be responsible for the design and positioning of CCTV cameras at strategic locations, mounted on buildings or using masts as required, to achieve the full coverage of the perimeter fence and gates. The CCTV system shall be designed to allow persons to be clearly seen at any position within the area of coverage. The CCTV images displayed on the monitors shall be of adequate clarity that will provide clear and unambiguous identification of persons or motor vehicles. Solid state CCTV cameras utilizing charge coupled devices (CCD) capable of providing high definition colour video images shall be provided. Cameras installed in areas which are likely to be subject to changing light levels shall have lenses equipped with auto iris control facilities.

- 8.18 -


Infra-red lighting shall be provided for cameras where the level of illumination during the hours of darkness is insufficient to give a clear image. The beam width of the lighting shall be matched to the focal length and coverage of the camera. Infra-red lighting shall be switched automatically by photo-cells during the hours of darkness.

A digital storage system shall be provided capable of storing the CCTV images in time lapse or in real time modes as required. The images shall normally be stored in time lapse mode. The storage system shall have facilities to superimpose camera number and date/time data on the images.

A sufficient number of colour TV monitors shall be capable of displaying the image from any of the cameras on the system. The quantity of monitors shall be to approval. The monitors will be located in the CCR and the Gate House.

An intruder detection system shall be supplied as part of the Contract. When an alarm condition is initiated, the security lighting in the zone and adjacent zones shall be switched on and images from the cameras in the zone and adjacent zones shall be displayed and recorded automatically. The intruder detection system shall alert security staff that an attempt has been made to enter the station via the security fence. Facilities shall be provided to manually control the security lighting.

A site access control system shall be provided that covers all site access points. The site access control system shall consist of motorized gates, intercom between gates and CCR/gatehouse and facilities to operate gates form the CCR and gatehouse. CCTV cameras shall be located at all access points to provide clear identification of people and motor vehicles.

Full details of the proposed intruder detection system, CCTV and access control system shall be provided with the bid submission.

8.19 Weather station

Weather instrumentation shall be installed to provide the PCS with the following signals:

a. Ambient air temperature.

b. Atmospheric humidity.

c. Atmospheric pressure.

d. Wind speed.

e. Wind direction

The weather station shall be provided with all necessary housing and auxiliary equipment and shall be suitable to withstand the full range of climatic conditions arising at the site. The weather station equipment shall be located in an open area away from any structures that may affect measurement accuracy.

- 8.19 -


8.20 General requirements

8.20.1 Introduction

The following section describes the general requirements for the supply and installation of the control and instrumentation (C&I) systems for the plant. All C&I equipment necessary to allow the safe, reliable and efficient operation of the plant shall be supplied.

8.20.2 Environmental requirements

In general, equipment supplied shall conform to the environmental classes defined in BS EN 60654. The internal air in an equipment cubicle will, at least in some parts, be higher than the defined ambient temperature. For design purposes the internal air shall be taken as 15°C higher than defined maximum ambient given in BS EN60654.

In operation, during installation and maintenance, and during transit, the equipment may be subjected to continuous vibration and shock loads. The mechanical design shall take account of these conditions to minimize the risk of failure.

Instruments shall be mounted in heated or protected locations wherever possible in order to minimize the effects of ambient weather conditions.

All field mounted instruments will be weatherproof to IP65 or equivalent and suitable for the local operating conditions. Field mounted instruments shall be provided with a suitable shade to protect them from direct sunlight. All instruments, instrument tapping points and controls shall be accessible from floor level or permanent platforms.

Instruments in water services or where water can accumulate in the impulse lines shall be trace heated where the ambient temperature can fall below 0°C. Wind chill factor shall be considered.

8.20.3 Hazardous areas

All C&I equipment shall be suitable for the specific area in which it is located. If equipment is expected to operate in the presence of flammable or explosive materials either explosion proof construction or the use of barriers to obtain intrinsic safety will be acceptable. All equipment offered for use in such areas shall have the necessary certification by the appropriate Certification Bureau and its proposed application shall fully comply with all conditions of the certificate.

The design and installation of the equipment shall take into account fully the appropriate sections and requirements of BS5345/ BS EN 50014.

8.20.4 Insulation and isolation

All circuits intended to be electrically isolated from external circuits shall be designed to withstand the following voltage levels:

a. All circuits requiring isolation (including contacts of switches, relays or contactors) shall have an insulation resistance across the isolating barrier of not less than 20 Mega ohms when measured at 500 V dc.

- 8.20 -


b. A circuit intended for connection to 110 V ac or 125 V dc and above shall withstand 2 kV 50 Hz rms between itself and all other points for one minute.

Connections to the external power sources shall normally be made via switches and fuses or via miniature circuit breakers.

8.20.5 Electromagnetic compatibility (EMC)

No equipment provided under the contract shall generate electrical or electromagnetic interference at a level detrimental to the performance of other equipment or to a hazard or of discomfort to personnel. The equipment shall meet the requirements of BS EN 55011 Class A Group 1.

8.20.6 Identification

Each item of equipment shall be durably and legibly labelled, indicating the purpose, plant identification number and where necessary any operating position functions. Labels shall be provided on front and rear access doors of all cubicles. Labels shall also be provided inside cubicles to assist the identification of apparatus and terminals. Instruments, valves, actuators and all other field-mounted equipment shall similarly be identified with suitable labels.

The material of all labels and the dimensions, legend and method of printing shall be to approval. Surfaces of labels for cubicles and control equipment shall have a matt or satin finish to avoid dazzle. Colours shall be permanent and free from fading. Danger labels shall have red lettering on a white background.

8.20.7 Installation

All instrumentation shall be installed in compliance with BS 6739 or international equivalent standard and the recommendations of the manufacturer. Only one instrument shall be fitted to each tapping point. Separate instruments shall be provided for control/indication and protection systems.

Connections to instruments after the primary isolating valve shall be made using steel or a material corresponding to the piping class of the line to which it is connected. Stainless steel (316) shall be used in certain atmospheres to prevent erosion or corrosion problems. Instrument isolating valves, vent/test valves and instrument manifolds shall be provided for all devices where appropriate. Instrument vent and drain points shall be routed to a safe position away from site personnel.

All indicating instruments and controls shall be readable and accessible from floor level or permanent platforms. Local gauge glasses shall be visible from any control valve that controls the vessel level. Instrument ranges shall be such that normal working indication lies between 60 and 75 per cent of the span.

Post or bracket mounts for instruments shall not be attached to pipe work, removable flooring, and handrails or be directly affixed to machinery and equipment subject to vibration.

- 8.21 -


8.20.8 Flow measurements

Flow measurement devices operating on differential pressure principles shall be designed in accordance with the requirements of BS 1042. For high pressure applications, the carrier for the primary device shall be of similar material to the pipeline in which it is to be mounted, and shall be connected into the pipeline by butt-welding. Other applications shall use flanged connections wherever possible. For line sizes below 50 mm, a precision pipe assembly shall be utilized with a minimum line size of 50 mm. All differential pressure devices shall be provided complete with tapping point isolation valves, 3-valve manifolds and drain valves or 5-valve manifolds, as required.

Positive displacement flowmeters shall be used for custody transfer flow measurements. The flowmeters shall in all cases be suitable for the process conditions applicable to the measurement location and the environment in which it is mounted. Meters used for energy, tariff or metering purposes shall be supplied, complete with adjacent pipe sections, where necessary, with calibration certification from an approved laboratory. Displacement flowmeters shall be capable of accuracies to within ±0.25 per cent.

Where density, temperature or pressure corrections to tariff metered performance monitoring signals are required, then such measurements shall be made close to the flowmeter location.

Flowmeters employing alternative measurement principles may be utilized for appropriate applications subject to the approval of the Owner.

8.20.9 Level measurements

Level measuring devices may be of the direct measurement, differential pressure or electrical/electronic type as appropriate to the application. For local indication of level, direct measuring devices shall be used. Level measuring equipment shall be capable of being removed without the vessel or other instruments being taken out of service.

Level gauges shall be of the reflex type made from stainless steel bar and fitted with toughened borosilicate glass and marked with their safe working pressure and temperature, except on low temperature and pressure application when transparent types may be used. Each gauge shall be fitted with top and bottom isolation valves with full bore drain valve at the bottom and plugged vent at the top. Gauges shall be arranged so that the visible length is in excess of the maximum operating range.

Differential pressure transmitting devices shall preferably be used on all services other than slurry.

Displacement type instruments and switches shall be mounted in external cages with flanged connections rated the same as the vessel. This type of instrument shall not be used for applications involving viscous, corrosive or flashing liquids.

Direct measurement of level by means of internally mounted floats etc, shall only be used when the switch point is either well defined in advance or if it is adjustable in service, if the vessel can

- 8.22 -


be emptied and/or depressurized for the removal of the switch without affecting the normal operation of the plant, or where choking of extended connections is likely to occur.

Float switches shall be glandless with magnetic coupling.

8.20.10 Pressure measurements

In general, local pressure gauges shall operate on Bourdon tube principles and shall comply with BS EN 837. Low pressure gauges may employ manometer or barometer devices to indicate small gauge, differential pressures or vacuums.

Sensing element materials shall be selected to resist corrosion by the process medium.

When gauges or transmitters are to be used for duties where the process medium temperature exceeds 70°C, siphon loops shall be utilized.

Gauges measuring low ranges that can be exceeded by a higher containment pressure shall be fitted with over-range protection. Gauges shall be fitted with vent/test valves. Blow-out devices shall be provided for high pressure applications.

Pressure switches shall only be provided with the approval of the Owner. If used, pressure switches shall be such that under normal process operating conditions the contact in the switch shall be closed unless otherwise approved by the Owner.

8.20.11 Temperature measurements

The method of temperature measurement to be employed shall be selected for the particular application bearing in mind requirements for accuracy and reliability. Sensing elements for air, inert gas and radiant temperature measurements shall be complete with suitable protective sheath. For steam, water and hazardous applications, thermowells shall be utilized.

Resistance thermometer detectors (RTDs) shall be used only where they can be readily replaced without loss of plant capability. RTDs shall be to BS EN 60751 Grade II using 3-wire connections for applications up to 450°C. On differential temperature measurements RTDs to BS EN 60751 Grade I will be used.

Thermocouples shall be used in accordance with the requirements of BS EN 60584. Careful consideration shall be given to the design and installation of thermocouple systems to ensure that inaccuracies are not introduced into the measurement due to the use of unsuitable materials or by incorrect installation. Cold junction compensation shall be provided as well as compensating cables of suitable size and material where required. Thermocouples shall be installed in such a way as to be capable of replacement with the plant in operation.

Local temperature indicators shall be supplied with a thermowell and shall preferably be of the bimetallic type and of the multi-angle variety.

No temperature measuring system shall use mercury as its sensing medium.

- 8.23 -


8.20.12 Position measurements

Position measuring devices or switches (eg limit switches, proximity switches etc) shall be remote from sources of heating or leakage of process, gases or liquids. Where vibration-free locations are not possible, the mounting arrangement shall incorporate flexibility in the coupling between the device and the point of measurement and the transducer mountings.

For position instruments in high temperature applications the calibration of position transducers and the setting of limit switches shall be unaffected by the hot/cold operating temperatures of start-up and shutdown.

8.20.13 Quality measurements

Quality measuring instruments monitoring chemical or physical properties of process fluids and substances may be installed either directly in the process line or vessel or via a sampling system. Sensors shall be of rugged construction and shall not require frequent maintenance or re-calibration. Where sensors require the use of calibration solutions or gases, then a minimum of one year’s supply at normal usage shall be supplied. Where sensors require replacement or removal for re-calibration or rejuvenation at regular intervals, then an adequate number of spare sensors shall be supplied for one year’s normal usage.

8.20.14 Vibration measurements

Vibration measuring devices shall be of the non-contacting transducer type and shall be designed and selected for operation in their particular intended environment. Vibration transducers shall be located at or adjacent to each machine bearing mounted in tapped holes in the bearing housing or by rigid bracket. For the measurement of both relative and absolute shaft vibration two transducers shall be used radially mounted in the same transverse plane perpendicular to the shaft axis and 90° apart.

Relative vibration shall be measured by the use of non-contacting transducers (proximity type) to measure the relative motion between the shaft and bearing housing.

Absolute vibration shall be measured by non-contacting transducers, measuring relative shaft vibration, in combination with seismic transducer (velocity type or accelerometer), measuring the support vibration. Both transducers shall be mounted close together so that they undergo the same absolute motion in the direction of measurement. Their conditioned outputs shall to be vectorially summed to provide a measurement of the absolute shaft motion.

The measurement of both relative and absolute shaft vibration shall be broad band so that the frequency spectrum of the machine is adequately covered.

8.20.15 Control valves and actuators

Control valves shall be supplied with suitable actuators matched to the operational and environmental requirements of the plant. All actuators shall be provided with a means of local control which shall be capable of being utilized without the use of tools. Loss of remote/automatic operation of an actuated valve shall be alarmed to the operator.

- 8.24 -


All control valves shall have local and remote indication to show the actual position of the valve. For remote control or indication purposes a suitable position transmitter shall be provided (eg based on a linear variable differential transducer). Where it is only necessary to provide a limited number of discrete position indications, then position actuated switches shall be used. Switch settings shall be adjustable.

8.20.16 Motorized valves

Motorized valves shall be used for isolation purposes and shall consist of self-contained actuator units with motor, gearbox, contactor, controls, limit/torque switches and all auxiliary equipment installed in each actuator housing. A lockable local/remote selector switch with open/close controls shall be located on the actuator. The actuator shall be designed such that it may be disengaged from the valve if a fault has occurred and the valve operated normally by using the hand wheel.

Each end of the actuator travel shall be fitted with suitable limit and torque switches for preventing overtravel and consequential damage to the actuator. Limit switches shall be installed also to provide remote indication of the valve position. Local valve position indication shall be provided on the actuator.

8.20.17 Manual valves

Manual valves important to the process shall have their open/closed status monitored and displayed. In such cases limit switches shall be provided at each end of travel.

8.20.18 Pneumatic actuators/positioners

Pneumatic actuators/positioners shall be supplied suitably matched to the operational and environmental requirements of the valve or driven unit. Pneumatic actuators/positioners shall cause the valve or driven unit to operate over its full stroke, from a 0.2 to 1 bar signal by means of any of the following:

a. pneumatic signal direct to the actuator;

b. pneumatic signal to a positioner;

c. electrical signal to electro/pneumatic converter;

d. electrical signal to solenoid pilot valve.

Pneumatic actuators and drive units shall automatically return to a safe/pre-determined position upon signal and/or air supply failure unless the process operating requirements or the Specification dictate a “stay put” response. “Lock up” devices shall be provided where necessary to ensure the actuator remains in the operating position prevailing immediately before an air failure.

Volume boosters shall be provided on loops where fast-response is required (eg pressure) to enhance stability.

- 8.25 -


All positioners and electro/pneumatic converters shall be furnished with three pressure gauges, air supply, signal input and control air output, and an air filter regulator set with a lubricator.

Position transducers and limit switches shall be provided to give remote indications of the valve positions at the PCS.

8.20.19 Cubicles and racks

Unless otherwise stated all equipment shall be accommodated in suitable cubicles or racks. Cubicles, cabinets, racks and control panels shall all conform to applicable IEC 60297 standards. The general design of racks and cubicles shall be subject to approval. They shall be free standing, fabricated steel construction and shall not exceed 2300 mm in height. The lowest mounting point, plug-in group or terminal block shall be not less than 400 mm above floor level. The methods used for cubicle mounting, including the provision of anti-vibration mounts, shall be to approval. The welding of cubicles, cabinets, racks and panels to support steelwork is prohibited.

Internal lighting and maintenance power sockets shall be provided within the cubicles. All enclosures containing electrical equipment shall be provided with thermostatically controlled anti-condensation heaters.

Cubicle doors shall be provided and arranged to lie flat back when open so as not restrict access to the cubicle. The doors shall be of the lift-off type secured with 3-point locking system. Cubicles and doors shall be structurally stiff and braced to withstand twisting without distortion flush fitting and sealed with a gasket of rubber or other approved material to prevent the ingress of dust and vermin.

Cubicles and racks shall be complete with all necessary terminal blocks, cable glands, gland plates and earth bar with earthing connection. These items shall be located in an approved, easily accessible, position and so arranged that the terminals face the access direction for convenience during maintenance. The design shall be suitable for either top or bottom cable entry for all cables. The gland plates shall be removable and in the case of floor mounted bottom entry cubicles, shall be not less than 200 mm above the base of the cubicle to allow access for applying the cable gland. Where cable glands are not used then provision must be made to seal the cable entry to ensure that the cubicle is dust proof, vermin proof and has a suitable fire rating. In addition provision for adequate cable support within the cubicle must be made.

Forced ventilation shall not be used without the approval of the Owner. Where forced ventilation is approved, fans shall be duplicated to provide 100 per cent standby capacity and shall initiate remote alarms in the event of failure. Ventilation systems shall comply with noise limitations imposed by the international standards. Replaceable dust filters shall be provided.

Terminal boards shall include 20 per cent spare terminals after all external cables have been terminated including the screens and spare cores.

All C&I cubicle wiring shall consist of copper wires of not less than 1 mm2 cross-section except for wiring associated with switchgear control and protection and CT and VT secondary circuits which shall not be less than 2.5 mm2.

- 9.1 -


9. CIVIL WORKS

9.1 General requirements for civil works

9.1.1 General

This section of the Specification covers the civil engineering and building works (collectively referred to as the “civil works”) required for the construction of an open cycle gas turbine (OCGT) power station located on a specified site within Iraq. The civil works forms part of a design and build project provided by the Contractor under a turnkey contract and shall include any preliminary studies, fully detailed design and construction of all ‘civil works’, auxiliary works and services including building services systems necessary for the completion of the OCGT power station.

The civil works required shall include, inter alia, supplementary site investigations and data collection as deemed necessary by the Contractor, detailed design, preparation of construction drawings, procurement of materials, execution and maintenance of works complete in all respects, provision of record drawings, CAD diskettes and microfilms as described herein.

The Contractor’s attention is brought to the existing layout and services drawings included in the documentation. The removal and/or diversion of these, as defined herein, shall be included in the scope of work and the Contractor is required to fully allow for these works in this offer.

9.1.2 Civil programme and method statements

A detailed civil design and construction programme shall be submitted in accordance with the Conditions of Contract and as specified in other sections of this Specification.

The Contractor shall prepare comprehensive method statements for all major construction activities and submit these to the Owner/Engineer for review at least thirty (30) days prior to the commencement of the relevant activity. The method statements will include, but not be limited to, working methods, construction plant utilization, temporary works, construction sequence, security and safety arrangements.

9.1.3 Planning and building permits/approvals

The Contractor shall ensure timely submission of all necessary details to the Local Municipality and others for items relating to these conditions.

The Contractor shall be responsible for obtaining all building permits. Any application shall be made by the Contractor, and allowance for all costs related thereto shall be deemed to be included in the Contract.

The Contractor shall be responsible for preparing and issuing all necessary documents required for obtaining the above mentioned building permits/approvals.

The Contractor shall make allowance for the above procedures in his programme for the Works.

- 9.2 -


9.1.4 Site investigations

Any Site survey, geotechnical and other subsurface information, hydrological and meteorological data if provided with this document for “information purposes”, shall not relieve the Contractor of his responsibility for fully assessing for himself surface and sub-surface ground conditions and buried constructions and obstructions. The Contractor shall be fully responsible for arranging his own site survey, geotechnical, contamination and hydrological investigations which are necessary to fully assess surface and sub-surface conditions on Site and to determine any necessary meteorological data prior to designing the Works.

Any further geotechnical investigation shall be carried out by an approved independent subcontractor specializing in soil mechanics and foundation engineering.

All Site investigations shall comply with BS 5930 and BS 1377 or equivalent Standards. All geotechnical and laboratory testing shall be conducted in a NAMAS accredited laboratory or similar approved. The Contractor’s scope of work, method statement and standards used in carrying out the site survey and geotechnical investigation, borehole layout etc, shall be submitted to the Owner/Engineer as a Design Intent Memorandum (DIM) for approval not less than 4 weeks before the site investigation work commences.

The Contractor shall submit to the Owner/Engineer all reports on the geotechnical investigation as the work proceeds, followed by a Final Report for the Owner/Engineer’s approval, containing complete borehole logs, results of in situ and laboratory testing and his DIM with respect to the philosophy for foundation designs, with verification and justification of the chosen designs.

The cost of all Site survey, geotechnical, contamination, hydrological and meteorological investigation work shall be deemed to be included in the Contract Price.

The Tenderer shall submit with his Tender details of any further site investigation works he proposes to carry out prior to and during the construction of the Works.

9.1.5 Ground contamination

The results of any contamination survey carried out by the Contractor shall be advised to the Owner/Engineer. The Contractor, Owner, and the Engineer shall agree on the necessary remedial measures.

9.1.6 Design and construction

The Contractor shall make sufficient provision both in his programme and the Contract to cater for:

a. The discovery of, and remedial treatment or removal as the case may be of any underground foundation constructions and buried services, including artificial obstructions. The Contractor shall take into consideration the history and past uses of the Site.

b. The discovery of, and remedial treatment or removal to a licensed repository of any contaminated material.

- 9.3 -


c. The discovery of and remedial treatment of any unknown underground services. The Contractor’s attention is drawn to the information shown on the existing drawings which identifies some existing services.

d. The discovery of, and remedial treatment or removal/replacement of any unsuitable strata of material.

e. Any archaeological remains uncovered during the excavation of foundations for the plant shall be reported and investigated.

9.2 The site specific data

9.2.1 General

The descriptions of the specified site and relevant details are provided in other sections of the contract document. The general description of the site is contained in Section 1 of the Specification. Site drawings are provided in Volume 3. Site studies and investigation reports if available are included Volume 4 of the contract document.

9.3 Scope of civil engineering and building works

9.3.1 General

The Civil Engineering and Building Works to be provided by the Contractor under the turnkey contract shall comprise the full detailed design, detailing and preparation of construction drawings, construction, completion and maintenance of all the various foundations, structures, buildings, installations and services etc required for the installation, commissioning, operation and maintenance of the equipment and plant for the power station plus associated pipelines, storm drainage culverts and outfalls. The works will include, but not be limited to the items described in the subsections below.

9.3.2 The Contractors enabling works

The Contractor’s civil “enabling” works (early civil works) on the site, shall, after completion, allow the “normal” type of construction activities of the project to proceed without delays.

The Contractor shall investigate, assess and execute the “enabling” works required on the site. For information purposes the extent of the enabling works may include but not be limited to the following:

a. the extent of the existing, “live” or redundant buried services which exist and impact on the proposed OCGT arrangement. These are described above for information purposes, as far as they are known, and shall be removed or diverted (if they were “live”) where they clash with the new works.

b. the extent of the existing buried and above ground civil infrastructure which may impact on the proposed OCGT arrangement. Principally this shall involve the demolition and removal off-site of any buildings on the site and civil infrastructure which clash in position with the proposed new works.

- 9.4 -


f. The existence of weak soil is to be rectified. The density of the near surface soils may be loose although with depth the density increases. Accordingly, the allowable bearing capacity of the soils is low and the settlement characteristics can be high. The contractor shall determine his own geotechnical design parameters for the design of the foundations which may need to utilize piled type foundations where heavy loads have to be supported. Alternatively the whole site may have to be treated by an improvement scheme like installing stone columns at regular intervals. The contractor will have to prepare the site to a standard suitable for the installation of the gas turbine station.

g. The extent of the earthworks required for the proposed OCGT plant may involve a pre-contract cut and fill operation..

The earthworks shall be developed by the EPC Contractor to achieve an optimum arrangement, to satisfy both the site conditions and the operation and maintenance of the plant. This shall address the issues of site flooding and the high ground water table. Salt rich soils on the site should not be re-used as backfill material. The contractor shall ensure that the execution, control and testing of earthworks fulfils the project requirements and complies with the recognized Standards and codes of practice. These will include the American Society for Testing and Materials Standards (ASTM), material codes for grading, and compaction codes to achieve a minimum degree of compaction of 98 per cent ie ASTM D 698.

The Contractor shall allow for all dewatering necessary to keep excavations clear of water during construction.

9.3.3 Scope of main civil engineering and building works

9.3.3.1 Summary of scope

The proposed main civil works comprising the OCGT facility include the following:

a. Site establishment

b. Verification/identification of existing buried services and civil infrastructure

c. EPC contractors confirmatory geotechnical investigations and topographical survey

d. Demolition of existing infrastructure impacting with the proposed OCGT facility

h. Earthworks and site preparation activities to form proposed platform for the OCGT facility

i. Piling and foundation works for the GT foundations and associated buildings

j. Construction of all associated buildings, including building services for open cycle operation and considerations for later combined cycle expansion if specified in the contract. The buildings are shown on the Tender arrangement drawings.

- 9.5 -


k. New roads, car park, drainage and other yard works, including fencing.

l. Consideration of requirements for future CCGT conversion.

9.3.3.2 Scope/descriptions of main civil engineering and building works

The scope of works listed below and the descriptions provided, are not intended to cover every particular aspect of the OCGT works, but are intended to assist the Contractor to develop, design and construct the most suitable arrangement of civil and building details to fulfil the requirements of the contract.

In addition to the items described below, the Contractor shall make full allowance in his price and programme to carry out all investigations, surveys, demolition and removal of all buried structures and services impacting upon the new OCGT works, excavation of any unsuitable materials, importing replacement materials, site preparation, filling, site grading, and flood prevention in order to design and construct the works.

The new OCGT works shall comprise, but will not be limited to, the individual areas for the various plant items and buildings, separately or combined as follows:

9.3.3.3 Gas turbine area

Particular attention shall be given to the design of the foundations for the gas turbine to ensure that all criteria including vibration, thermal effects, short circuit torque forces and mechanical resonance and critical concrete tolerances are fully accommodated. The Contractor shall determine his own requirements to suit the plant arrangements, loadings and soil conditions.

The foundations shall be of sufficient size to facilitate the installation operation and maintenance of the packaged plant supplied and to adequately protect the plant from the environmental conditions. It shall comprise unitized and isolated foundations supporting the gas turbine generators and auxiliary/ancillary plant. Adequate clear working space between units for laydown and loading bays shall be provided. The contractor shall propose a working space and obtain approval of the same during early development of the plant arrangement. Laydown and loading bays shall be paved areas of adequate strength for their applications.

Suitably sized foundations shall be provided to accommodate central and local control rooms, switchgear, battery and LVAC rooms, laboratory, offices, kitchen and toilet facilities.

The floor slab between the turbine generator blocks shall incorporate trenches and be constructed of reinforced concrete and laid to falls to floor drainage gullies discharging into oily water separators. Trench covers shall be designed to accept the appropriate floor loadings according to their location and shall be manually removable, wherever possible.

Drainpipe routes shall be routed clear of all electrical equipment.

9.3.3.4 Black start/emergency diesel building

The Contractor shall determine the requirements for foundation supports.

- 9.6 -


A fully enclosed building with exhaust stack shall be provided for the black start/emergency diesel generator plant to ensure the equipment is always available as an essential facilities and free from damage and degradation from the elements.

The foundation for the black start/emergency diesel package unit shall be sized to accommodate the plant to be installed and to facilitate the operation and maintenance of the plant. Galvanized chequer plate sub floors and trench systems shall be provided as necessary to facilitate access to the fuel piping, pumps, input and output cables. Floors and trenches shall be laid to drain to floor gullies connected into the drainage system via an interceptor.

A diesel fuel tank contained in bunded walls shall be provided outside the building.

9.3.3.5 Transformer foundations and compounds (with fire walls and bund walls)

The Contractor shall determine the foundation requirements for foundation supports.

The transformer support substructures shall be designed to contain any escaping oil. The oil retaining structures shall be filled with fire quenching graded round stones providing an air void capacity at least 10 per cent in excess of the transformer total oil volume. Segregated ducts shall be provided for any cables installed within the substructures.

The transformer support structure shall incorporate guide rails for transformer installation and withdrawal.

Each compound shall be provided with oil sump pumping out facilities and shall also be connected with the site drainage system via oil/water separators with water outlets drains and oil retaining chambers with pumping out facilities.

Each compound shall be provided with fire and blast resistant walls to sides and rear to prevent fire spreading from one compound to another and to the gas turbine area. Firewalls shall be designed for a minimum 3 hour fire resistance.

All trenches in the compounds shall be filled with sand and be sealed to prevent the passage of oil spread or fire and water into buildings.

The dimensions of each compound shall be adequate for installation, operation and removal, and to allow for sufficient cooling of the transformers.

The front of each compound shall be provided with a close fitting robust, easily removable, framed aluminium fence incorporating a personnel gate.

The road in front of the enclosures shall be of concrete construction.

9.3.3.6 Stacks and flues

The Contractor shall determine the requirements for foundation supports.

The area surrounding the stack shall be surfaced with a concrete slab.

- 9.7 -


A fully integrated drainage system, including wash down discharge, shall be provided. Chemically polluted discharge and wash down effluents shall pass into a suitable designed pit.

Foundations shall be provided for each stack, and shall be designed to withstand the most unfavourable combination of static, dynamic, environmental and erection loads.

The layout of the main gas turbine stack shall include suitable considerations for future upgrading to a combined cycle system.

9.3.3.7 Fuel (gas) oil storage tanks and fuel forwarding pumps

The fuel oil tanks shall be supported on suitable foundations, if required, incorporating piled reinforced concrete ring beams. This is to be determined from the Contractor’s investigations and technical assessment of the geotechnical parameters of the sub soils.

A surface water drainage channel shall be laid around each tank. The surface within the bund area shall be sealed to prevent the seepage of oil into the substrata. All drainage including that from the tank roofs shall be passed into an oil interceptor system before passing into the site drainage system. Provision shall be made for the removal of oil from the interceptor. The whole system shall be designed to meet the current Standards and practice for drainage work of this nature.

The fuel forwarding pump house shall contain trenches with removable covers or ducts (for cable and pipes), concrete plinths for mounting pumps and electric motors, and facilities for supporting all control equipment, pipes and cables.

Floors shall be laid to falls leading to drainage channels connecting into oil interceptors. Oil interceptors and sumps serving the fuel oil system are to be equipped with oil/water or level detectors with alarms.

Suitable bunding shall be constructed to prevent any spilt oil entering into the ground. All ducts and trenches shall be sealed to prevent oil entering into the adjacent ground. Suitable barriers shall be provided to prevent damage to pipework and valves.

9.3.3.8 Site area for fuel gas receiving compound/area

The Contractor shall be responsible for connecting to the gas pipeline and for the provision of all gas conditioning equipment and their associated foundations.

This preparation for the gas compound area shall, as a minimum, consist of stripping a minimum of the top 300 mm of soil, levelling and rolling the sub-grade; placing a geotextile membrane over the area capped with a minimum of 300 mm compacted approved granular fill, to bring back to the same level as the surrounding site. The Contractor shall determine precisely what the preparation of the Site is to be, to match the foundation and layout arrangements for the area.

The layout and location of the gas receiving station/compound shall include suitable considerations of fire and explosion risks to the operational staff and the overall safety of the station.

- 9.8 -


9.3.3.9 Control and administration building

The planning of the building shall be carefully considered to form a pleasing, functional arrangement, with a high standard of architectural design which is to integrate with the overall design concept for the remainder of the site. All fixtures, fittings and finishings shall be of good quality, appropriate to their function and location within the building.

The floor to suspended ceiling height for all rooms shall not be less than 3 metres.

Suspended ceilings shall be provided throughout. Light fittings and ventilation grills etc. shall be flush fitting, and all ducts, pipes and services shall be concealed above the ceiling.

Doors provided solely as a means of escape shall be fitted with panic bars and shall not be openable from the outside.

Solar reflective double glazing shall be provided throughout to all windows and doors. Opening lights shall be provided for a proportion of all window areas.

All offices shall be fully furnished to a standard and style appropriate to the proposed occupancy.

The Contractor shall provide as a minimum the following accommodation in the Control Building:

a. Switchgear room

b. Central control room

c. Plant manager’s office

d. Operations manager

e. Maintenance manager

f. Secretary/Clerk

g. Shift Supervisor

h. Kitchen

i. Conference room, suitable for at least 12 persons

j. Permits room

k. Electronics room

l. Telecommunications room

m. Men’s locker/change facility (with toilets, showers, lockers, etc) for 25 operators

- 9.9 -


n. Women’s locker/change facility (with toilers, showers, lockers, etc) for 4 operators

o. Janitor’s closets.

Externally a 1.5 m wide pathway shall be provided all around the building with access to the entrance and escape doors. This path shall be edged with curbs set in concrete and surfaced with precast concrete paving slabs.

9.3.3.10 Chiller building

The Contractor shall determine the superstructure and foundation requirements for the infrastructure housing the chiller plant. The provisions shall be such a manner to enable the chiller plant to be installed properly, to shield the equipment from damage from the environment, to operate equipment satisfactorily and ultimately to be able to carry regular maintenance work on the plant with suitable spaces and facilities under a protected environment.

The chiller building shall be suitably sized to house the chiller plant required for the station. Furthermore, the chiller building shall contain, where applicable, a separate area for switchgear, offices and toilets with a mezzanine floor above for housing the air conditioning units for the chiller building. Galvanized chequer plate covers shall be provided as necessary to facilitate access to trenches which shall contain all pipework, cabling etc within the building. Floors shall be laid to fall away from equipment and trenches to floor drainage gullies connected into the drainage system. An area for the chiller cooling system shall be provided external to the main chiller building to be housed within a louvre sided compound to prevent the ingress of sand and dust.

The chiller plant area shall be served by an overhead electric crane or hoisting facilities suitable for maintenance of the chiller plant. Doors shall be provided to allow large items of plant to be brought in or removed for maintenance. Personnel doors shall be positioned beside the main doors.

The offices shall be fully furnished and ready in all respects for occupation.

9.3.3.11 Workshop and stores

The Contractor shall determine the foundation requirements.

The workshop shall be fully equipped with all necessary machine tools, work benches, hand tools, etc, shelving and fittings for the storage of all tools and materials. It shall be provided with an overhead travelling electric crane and other necessary lifting equipment.

The dimensions of the workshop shall provide sufficient space for efficient working on all plant and equipment as necessary to maintain the normal running of the station.

Doors shall be provided to allow large items of plant to be brought in for maintenance. A personnel door shall be positioned beside the main door.

The offices shall be fully furnished and ready in all respects for occupation.

- 9.10 -


The tool room shall be fitted with shelving and racking suitable and sufficient for the satisfactory operation of the station in all circumstances.

The workshop records room shall be fitted with filing cabinets and shelving.

Doors shall be substantially constructed of pressed steel surfaces with wood or rigid foam cores and shall be mounted in pressed steel frames.

9.3.3.12 Effluent basin/evaporation pond

A effluent basin/pit shall be provided for collecting, monitoring and dosing the chemical discharges generated from the operation and maintenance of the gas turbine plant. The by-products from the regeneration and ion exchanges from the demineralized water system shall be contained by a neutralization basin suitably constructed with a chemical resisting liner. The basin shall form a temporary holding area with sufficient capacity for the whole station to operate without disruption. Discharges from the effluent basin shall meet the environmental regulations in force.

Where no facility to discharge to a public drainage system exists, the site shall be equipped with a suitable size evaporation pond where all treated effluent can be removed by evaporation.

All civil and building works comprising the effluent basin shall be to the latest Standards. The structure shall be robust, fully functional including any infrastructure as necessary to fulfil the Contract requirements.

9.3.3.13 Water treatment plant

The water treatment plant will comprise raw (service) water and demineralized storage tanks, pump stations, water quality control equipment, sampling laboratory and analysis. The scope of the civil works shall include all provisions necessary for the above.

The Contractor shall determine the foundation requirements for the bulk storage tanks, pumps and the building etc. The bulk storage tanks shall be supported on suitable foundations as noted in 9.3.3.7.

A building shall be provided incorporating the following facilities:

a. Chemical stores. Adequate storage shall be provided to accommodate all of the chemicals required for operation and maintenance of the water treatment plant and dosing equipment.

Provision shall be made for appropriate washing and first aid facilities adjacent to each store.

Adequate facilities shall be provided for the safe handling of all chemicals.

Air-conditioned storage space for reagents and space for storage of glassware and spare items shall be provided.

- 9.11 -


b. Chemical laboratory. A fully equipped laboratory for the testing required for the plant shall be provided within the building.

All necessary furnishing shall be provided to ensure adequate operation of the laboratory.

The structure design shall allow for the use of cranes and lifting tackle for removal of plant.

A suitable plant unloading area shall be constructed.

The ground floor slab shall be reinforced concrete suitable for supporting all the plant and maintenance loadings. The surface shall be suitably treated or painted to resist the chemicals used. Spilled chemicals shall be confined by perimeter bund walls.

Removable duct covers and manhole covers shall be provided over permanent cable and pipe trenches and chambers. These covers shall be designed to accept the appropriate floor loadings according to their location and shall be provided with proper and adequate sealing.

Chemical resistant covers and frames shall be provided in chemical handling/storage areas. The bulk chemical store flooring shall be chemical resistant and be suitable for forklift movements to be used for chemical stacking purposes.

Emergency exit doors shall be provided, except to toilets, fitted with panic bar type of operation.

The building shall be ventilated and lighted as required.

For plant operation or maintenance, allowance will be made for discharge or spillage of wastewater or other fluid, and adequate provision shall be made for collection and disposal.

9.3.3.14 Fire fighting pump house

The Contractor shall determine the foundation requirements for the pump house and storage tank.

The pump house shall be sized to accommodate the plant to be installed and to facilitate the operation and maintenance of the plant. Galvanized chequer plate sub floors shall be provided as necessary to facilitate access to the pumps. Floors shall be laid to fall away from pumps and trenches to floor drainage gullies connected into the drainage system via an oil interceptor.

A diesel fuel tank contained in bunded walls shall be provided outside. A foam tank and distribution pipework shall also be supplied and installed under this contract, details of which are given in this Specification.

- 9.12 -


9.3.3.15 Security gatehouse

A fully functional security gatehouse shall be provided adjacent to the main access gate to the site. It shall be of adequate size to fit its purpose.

The building shall contain controls for operating main gates, lifting barriers and any installed turnstiles plus the CCTV system. There shall also be a security staff working area with reception desk, visitor waiting area, private office, welfare facilities comprising kitchen/staff room and toilet, plus an adequate filing area and storeroom.

It is a requirement of the contract that adequate provisions shall be installed to deter forcible entries by motorized vehicles from the outside. The gate house therefore should be adequately strong.

Additional security measures, if required, shall be specified in the general conditions of the contract.

9.3.3.16 Access roads, paved hardstanding areas (for car parking), concrete slab lay-down areas, gravel covered sterile areas, pathways and landscaped areas

Entrance to the site for construction purposes shall be through an existing access or a new access road if specified by the contract.

The Contractor shall construct permanent new access roads and/or shall improve/re-surface existing roads (where retained) such that they meet the design requirements to fulfil the requirements of this contract.

Roads shall be a minimum of 7.3 m wide and may be constructed with either asphaltic concrete or concrete pavements, but concrete paving shall be provided where petrol/oil or other chemical spillage may occur.

The roads within the site areas shall be constructed between raised kerbs and graded to falls leading surface water into gullies or catchpits that will connect into the drainage system.

The Contractor shall take reasonable steps to maintain the free movement of traffic on any roads used by him to gain access to the site. All roads shall be maintained free of any spillage from the Contractor’s vehicles.

The radii of bends, particularly those at intersections, will be designed to allow for the longest and biggest vehicle necessary for the installation, commissioning, operation and maintenance of the power station site to take the bend in one manoeuvre without mounting the kerb.

Turning areas shall be provided at blind ends.

Bollards shall be provided in roadways near equipment, which need protection from vehicular impact.

- 9.13 -


The layout and construction of access roads, paved areas, etc shall be carefully assessed to effectively serve the power station arrangement, but also match in to the existing road system(s).

9.3.3.17 Drainage systems (storm water, oily water, chemical drainage and foul water)

The quality of all temporary and permanent drainage discharges from the site shall comply with the local authority requirements.

The drainage for the power station shall be designed to collect and transport:

a. storm water, all surface water run-off

b. oil water, contaminated water from mechanical equipment and fuel storage areas

c. foul water, domestic sewage; and

d. trade effluent, chemical wastewater, produced during the operation and maintenance of the plant.

Road gullies shall have removable covers to facilitate the removal of sand accumulated during a sand storm. See also Section 9.4- Design of the works and Section 9.6 - Materials and workmanship.

9.3.3.18 Site services

In addition to the drainage system, referred to above, the site services shall comprise all necessary cables, plant pipework, telephone cables, fuel gas, fuel oil, domestic water for fire fighting, demineralized water, etc. All these services shall be provided to meet the demands identified, to ensure the plant runs effectively. They shall be located to reduce the amount of excavation, the number of valves required and the total length of pipework needed. This optimization shall be balanced against the needs of other facilities. See also the Sections 9.4 and 9.6 for specification of the design of the works, and the materials and workmanship.

9.3.3.19 Underground cable ducts, drawpits, service trenches etc

Where pipes are to be laid under roads they shall be encased in concrete or laid in trenches with covers. Where cables are to be laid under roads they shall be laid in ducts, grouped and encased in concrete.

Trenches for pipes and cables shall be provided in reinforced concrete construction with connections to the site drainage system, to allow dispersal of water from within the trench. They shall be fitted with manually removable, well fitting covers such that they will withstand all loadings from traffic with out rocking or excessive leakage.

All overhead pipe runs shall be carried in properly designed structural steel pipe racks. The route location for any pipe rack will be to the approval of the Owner/Engineer.

Height markers will be provided at all road crossings. Road clearance will not be less than 5 m.

- 9.14 -


All site services shall be indicated on co-ordinated services drawings.

The Contractor shall be responsible for the sealing of oil ducts, trenches and wall penetrations to prevent the spread of flame, sand and water. This shall include any duct or opening for future use.

Cable drawpits and chambers shall be of adequate size to enable the designated cables to be laid and installed to the correct bending radii.

9.3.3.20 Security fences and gates (columns for security surveillance equipment and site lighting)

The site boundary shall be closed with a permanent fence, inclusive of gates, foundations etc.

The main power station access shall be furnished with a vehicular gate with a clear opening of at least 8 m, together with the adjacent personnel gate and an electrically operated balancing filter barrier complete with skirt. The gates shall be operable by push button at the gate and from within the gatehouse. The entrance and the perimeter fence shall be monitored by CCTV.

Other access points shall be provided around the perimeter as required for normal operation and maintenance and for emergency vehicle access.

Perimeter lighting requirements shall be as specified in the building services systems Section 9.7.

9.3.3.21 Concrete slabs for miscellaneous pipe supports between buildings, structures, fabricator termination points (to be co-ordinated by the Contractor)

Where required, concrete slabs shall be provided for miscellaneous pipe supports between buildings, structures and fabricator termination points.

9.3.3.22 Building contents (ironmongery, fixtures and fittings, internal finishes, furniture, office computer equipment, fire and safety equipment)

All buildings shall be fully completed and functional so that the Owner/Engineer can thereafter move in his “loose” furnishings in order to occupy the buildings.

All buildings shall be fully fitted out including: ironmongery, fixtures and fittings, internal finishes, furniture, office computer equipment, laboratory equipment, fire and safety equipment etc. The quality and quantity of items supplied shall be commensurate for this type and size of plant and fully adequate for the operation and management of the power station. The Contractor shall propose exact itineraries and specification for approval by the Owner/Engineer.

9.3.3.23 Interfaces with associated contracts

The Contractor for the power station will be required to:

- 9.15 -


a. where necessary provide the gas pipeline and other contractors with free and unlimited access to their site and interface locations at all times, including provision of a temporary road during construction if required by his pipeline contractor.

b. attend and hold interface meetings

c. provide setting out co-ordinates and datum levels.

9.3.3.24 Miscellaneous foundations and trenches for mechanical and electrical installation

Trenches, internal to any facilities for the above, shall be covered with galvanized chequer plate covers. Any floors will be laid to fall away from the trenches.

External trenches shall be sealed to prevent ingress of water, or shall be laid to fall so that any ingress of water can be drained to a collection sump and then either gravity connected or pumped to an appropriate drainage system.

All ducts shall be laid to fall away from plant or buildings and any water collected in a sump and either gravity connected or pumped to an appropriate drainage system.

9.3.3.25 Builder’s work associated with building services installation

All builders works associated with building services installation shall be provided by the Contractor.

9.3.3.26 All temporary installations for the construction period, including Owners/Engineers office

The Contractor is responsible for providing all temporary facilities and installation for the contract period.

9.3.3.27 Building services systems

The building services systems specification is covered in Section 9.7 of this Specification.

9.3.3.28 Work outside the main site area designated for the OCGT plant

The Contractor will be required to provide works which are directly outside the area of the main designated OCGT plot of the site, in order to complete his responsibilities under the Contract.

The new Civil items outside the main site area include but may not be limited to the following:

a. surface water, gas and oil pipelines, buried structures and outfalls

b. foul water pipelines, buried structures and outfalls

c. perimeter access roads

- 9.16 -


d. fencing

e. demolition and removal, of surface and buried infrastructure impacting upon the new works.

The Works shall also include other works as described and/or implied in the Invitation to Tender which are necessary to complete for the satisfactory operation and maintenance of the power station.

The Contractor’s attention is drawn to the fact that other contracts may be in progress on the site during the OCGT power station contract period. The Contractor will be responsible for liaising co-ordinating and co-operating with these other contractors on or adjacent to the site, and for providing them with free and uninterrupted access at all times to those areas of the site required for their operations.

All aspects of the civil works shall be designed and constructed in accordance with the Enquiry Drawings, Specification and basic design data included therein.

It is not intended that this Specification covers every particular aspect of civil works design and construction. This, however, shall not relieve the Contractor of his responsibility for the satisfactory design, construction, completion and maintenance of the entire civil works, whether specified or not, necessary for the safe and proper operation of mechanical and electrical plant provided under this Contract.

The Contractor shall be responsible for obtaining all additional Site data required for the project and for complying with local regulations and procedures which may affect the design, construction and completion of the civil works and allow for this in his Tender to meet the specified commissioning dates for the Plant.

It is essential that the Contractor should visit the site before preparing his Tender for the purpose of examining the extent and nature of the work and means of access to the site, to familiarize and satisfy himself with respect to local and Site conditions and to ascertain for himself the availability of all labour, plant, materials, essential facilities like power, water and drainage discharge points for the satisfactory execution of the Works within the overall project programme. The Tender bid shall be deemed to meet all local and Site conditions and restrictions.

9.4 Design of the works

9.4.1 General

The Contractor shall develop an architectural design philosophy to provide a consistent design solution throughout the site. Unifying elements of materials, colour and detailing appropriate to the form and function of the buildings, their location and site, and for the associated plant enclosures and exposed plant should be selected to develop an appropriate theme for the development at the specified site. The development shall be designed for a life expectancy of at least 30 years.

The Contractor shall be responsible for developing the overall architectural concept for the power station, within the guidelines provided in this Specification. He shall submit with his Tender his proposals for the site layout and the architectural treatment for main and ancillary buildings, taking

- 9.17 -


account of the visual impact and function of the buildings, and their proposed relationship to each other on site whilst fulfilling the requirements set out in this Specification.

All buildings shall be designed to ensure that internal noise, vibration, temperature and dust levels are kept within acceptable limits to provide proper operating conditions for the plant which is to be installed and a comfortable working environment for the Owner’s operations and maintenance staff throughout the year. Noise limitations have been specified around the turbine hall and the design and construction shall fully take this into account.

Roofs and walls shall have insulated construction to achieve a ‘U’ value of 0.25 W/m2K or better.

The Contractor shall make provision in the designs for the maintenance of all high level buildings, both internally and externally.

The architectural concept for the power station buildings, including colour schemes and finishes schedules, shall be finalized and agreed with the Owner/Engineer at an early stage in the design process.

The dimensions of buildings shall provide adequate space for the safe installation and operation of all plant and equipment, its replacement, and for maintenance procedures to be carried out by the Owner/Engineer.

The design, engineering, procurement, construction, testing and commissioning for the civil works shall comply with the applicable American or British Standards and Codes, accepted International Standards and other local laws and regulations, including any applicable maritime regulations. In addition considerations shall be included to ensure the choices of external materials are durable against erosion by sand storms.

Reference to Codes and Standards is intended to provide a minimum measure of performance, design, safety and methods of construction which must be equalled or exceeded in order to be considered acceptable for use under this Specification. Whilst American Standards are referred to in this Specification ISO, EN or British Standards are acceptable provided they do not detract from the quality, safety, operability, life, efficiency, reliability, maintainability and durability of the equipment and materials furnished.

The Contractor shall be entirely responsible for the complete design and design check of the Works. Any assumption regarding design parameters should be stated and agreed with the Owner/Engineer.

The Contractor shall be responsible for the timely submission to the proper Authorities of details of his proposals for the works, including plant building colours and landscaping schemes as may be necessary in order to comply with all relevant legislation, including building permit approval.

Main plant buildings and ancillary buildings shall have structural steelwork frames, with the upper levels and roofs finished with a profiled, insulated colour coated sandwich panel cladding system and with concrete or reinforced masonry dado walls at lower levels. Administration and minor

- 9.18 -


buildings may be of reinforced concrete or brickwork construction. The choice of external building materials shall be durable against the sand storm erosion.

Buildings shall be designed to comply with the relevant parts of the following fire precaution Standards:

a. BS 5588 Fire Precautions in the Design and Construction of Buildings.

b. BS 5908 Code of Practice for Fire Precautions in Chemical Plant.

Design calculations and analyses shall take into account the most unfavourable combination of static, and dynamic, erection and laydown loads and loads due to temperature and shrinkage effects, to which the structure or component part may be subjected, both for the serviceability and ultimate limit states. Methods of computation and magnitude of loads shall be in accordance with the relevant Standards and codes of practices.

For rotating machinery foundations the pedestal/foundation/soil system shall be designed for safe operation of the machine at any load within the speed range, without resonant vibration of the whole or any part of the system. Machine foundations shall be suitably isolated from all surrounding floor slabs and structural framing.

The Contractor shall provide all building services (electricity, telephone, computer, water, HVAC, fire protection etc) and ensure that they are readily accessible for maintenance and repair and adequate clearance is provided from main structural members and foundations.

The extent and layout of new roads shall provide suitable access to, and within, the new plant in order to allow erection and maintenance works to be undertaken effectively and with minimum disruption.

The dimensions of buildings shall provide adequate space for the safe installation and operation of all plant and equipment and for maintenance procedures to be carried out by the Owner/Engineer.

All buildings shall be provided with roof drainage for disposal of storm water and be connected to the OCGT station surface water drainage system.

A separate foul sewerage system for the power station buildings shall be provided.

A waste water system shall be provided for the power station. The Contractor shall submit a Design Intent Memorandum (DIM) describing the concept and design of the system. The design should allow for the separate collection, treatment and disposal of oily wastewater (arising from run-off, plant buildings, oil related operations and from major spillages) and of chemical wastewater (arising from demineralization systems etc).

9.4.2 Preferred structural design concept

The structural concepts described below are those preferred by the Owner/Engineer and considered appropriate for the specified site conditions and requirements of the Project. It remains

- 9.19 -


the Contractors responsibility under the Contract to consider these concepts as “information” to assist his own design and development of the civil works.

9.4.2.1 Structural frames

It is proposed that the Contractors design for all buildings other than the administration and control building, firewater pump house, black start/emergency diesel generator building, gatehouse and possibly the switchgear and control buildings shall be based on a structural steel framework.

The administration and control building, firewater pump house, black start/ emergency diesel generator building, gatehouse and possibly the switchgear and control buildings shall have either a reinforced concrete framework or a structural steel framework.

The frameworks of all related buildings shall be set out in such a way so as to allow free access for the installation and maintenance of plant.

Structural steel frameworks shall rely on rigid joints for stability or steel bracings, located at strategic locations in walls, roofs and floors to avoid plant access conflicts.

Reinforced concrete frameworks shall rely on either rigid joints or reinforced concrete shear walls for stability.

Movement joints, to control thermal movements and stresses, in all structural frameworks shall be provided at intervals not exceeding approximately 50 m.

9.4.2.2 Foundations and ground floor construction for buildings

The ground conditions at the proposed OCGT site at the specified site may be poor in terms of the allowable soil bearing pressure, settlement characteristics, high ground water table, and the sulphate and chloride contents in the soils and groundwater.

Foundations for steel framed buildings shall be constructed with their top level at a sufficient distance below ground to allow the structural steel baseplate and stiffeners to be hidden below ground and to facilitate rainwater pipe details an other architectural details. All structural steelwork below ground shall be protected with a durable, structural quality concrete surround. Structural steel column holding down bolt assemblies complete with washer plates and tolerance tubes shall be cast directly into the concrete bases.

The site level in the locality of the buildings shall be raised with an adequate depth of suitable imported compacted fill prior to commencement of the foundation works to ensure that no problems are encountered with the high water table.

Ground floor structures in plant related buildings may generally be of the ground supporting type and construction shall generally consist of compacted sub-base, polythene slip membrane and RC ground slab. This is subject to proper study and design by the Contractor. Contraction, expansion and isolation joints shall be provided to control cracking in the concrete caused by early thermal shrinkage strains and seasonal temperature variations. It is recommended that the floor is isolated from all vibratory type machine foundations, building superstructure and

- 9.20 -


perimeter walls. All slabs shall be reinforced top and bottom as a precaution against soft spots in the filled/replaced ground. As a minimum the concrete surface shall be treated with a surface hardener/sealer. A suitable joint sealant shall be applied to all joints. All joints in the ground floor construction shall be capable of carrying shear as necessary to prevent abrupt joints forming.

In order to maintain finishes and to support a possible random arrangement of masonry walls the ground floor structures in office type buildings may require to be provided with suspended RC concrete ground floors supported on RC ground beams, pile caps and piles. Also, in all areas of all building types where external and internal masonry walls are present then a similar suspended RC ground floor construction may be necessary or suitable provision for vertical movement should be made in the masonry to avoid cracking of the masonry. With regard to the latter alternative, differential movements at any such joints shall be minimal and shall be visually unobvious.

The allowable overall settlement for the building structures shall not exceed 25 mm and the maximum allowable differential settlement for building structures not exceeding 12.5 mm.

The overall and differential settlement of foundations for plant shall strictly adhere to the plant manufacturers requirements.

The general concrete Standard covering the design and construction of the building foundations and ground floors shall be American Concrete Institution (ACI) 318M-99/318RM-99: Metric Building Code Requirements for Structural Concrete and Commentary.

Other relevant Standards include:

a. ACI 302.1R-96 “Guide for Concrete Floor and Slab Construction, Part 2”

b. ACI 336.2R-88 “Suggested Analysis and Design Procedures for Combined Footings and Mats, Part 4“

c. ACI 336.3R-93 “Design and Construction of Drilled Piers, Part 4”

d. ACI 349.2R-97 ” Embedment Design Examples, Part 4“

e. ACI 360R-92 “Design of Slabs on Grade”

f. BS 8007 “Design of Concrete Structures for Retaining Aqueous Liquids”.

Later versions of the design codes shall be applicable if available at the time the contract is awarded.

If the ground conditions on the specified site consists of poor bearing soils at ground level with possible high concentrations of sulphates and/or chlorides in conjunction with a high water table, the concrete used in foundations and ground floor slabs, therefore, shall have a minimum 28 day cylinder crushing strength, cement content, cement type, water cement ratio and approved additives sufficient to provide the required durability for the life of the facility. These matters are specified in the concrete section of this Specification. Additional externally applied bituminous barriers shall be provided as necessary.

- 9.21 -


A maximum crack width of 0.3 mm will be incorporated in the design of foundations and ground slabs.

Any reinforced concrete (RC) constructions required to retain or exclude liquid and incorporated in the civils work for the buildings shall be designed for a maximum crack width of 0.2 mm in accordance with BS 8007.

9.4.2.3 Foundations for gas turbine plant

The GT foundation shall be a monolithic raft supported by piles unless otherwise justified by the Contractor. The exhaust stack may be supported by a separate foundation or incorporated within the foundation if required by the Contractor.

The contractor shall ensure that the following points are included in the GT foundation works:

a. A minimum rebar content of 80 kg/m3 of concrete shall be provided.

b. The design of the GT foundation shall satisfy, in addition to an appropriate internationally recognized design code on machine foundations, the following codes: CP 2012 and DIN 4024. CP 2012 requires an internal reinforcement cage system which is essential for the foundation to act as a homogenous mass and provide a second line of defence to the machine anchoring system with the holding down bolts. DIN 4024 provides guidelines for carrying out dynamic analysis.

c. The GT foundation shall be isolated from the rest of the works by floor joints.

d. The ratio of mass of the foundation to weight of the GT plant shall be at least 2.5.

e. To reduce the risk of dynamic compaction the maximum load on any pile supporting a GT foundation shall not exceed 50 per cent of its working capacity during the normal operating conditions and shall not exceed 85 per cent in extreme conditions. For a foundation supported by soil the same limits apply to the allowable bearing capacity of the soil.

f. The design of the GT foundations shall include the thermal effects on the foundation and its ability to withstand the extreme differential temperatures likely to be experienced by the foundation, during the construction as well as throughout its design life. Protective measures during construction shall be part of the design.

g. The section of the GT foundation below ground shall be protected with a coating system to resist attack from the sulphate content in the soils and chlorides from the ground water. Further protection against corrosion of the reinforcement (which leads to expansion of the concrete and cracking) due to the severe chloride ion content of the soils and groundwater shall be provided as covered by the concrete section of this Specification.

- 9.22 -


h. The GT foundation shall be poured in one operation and construction joints are not permitted unless in exceptional circumstances and with the approval of the Owner/Engineer.

i. The design, detailing and construction of the GT foundations shall allow fully for the “buildability” of the foundations, particularly where congested areas of reinforcement are required.

9.4.2.4 Suspended floors

Suspended floors shall be of reinforced concrete (RC) construction, however galvanized open grid type flooring (minimum bars 40 mm x 5 mm at 30 mm c/c) or galvanized chequer type plate flooring (minimum thickness 8 mm) can be used for plant access platforms, access walkways and landings. All open grid and chequer type plate flooring shall be securely clipped to structural supporting beams.

Reinforced concrete floors shall be solid but in order to speed construction galvanized steel profiled sheeting may be used as a permanent formwork. The decking shall not be designed in composite action with the concrete slab. A re-entrant type trough profile only shall be adopted as described in BS 5950 Part 4 “Code of practice for the design of floors with profiled steel sheeting”. All proprietary galvanized edgings and void fillers shall be incorporated into the floor construction.

9.4.2.5 Roofs

All roofs shall be of lightweight construction using a suitable plastic coated galvanized steel insulated sheeting system. Where it is required to site heavy plant on roofs, or if there is a fire protection requirement, then the benefits of a concrete roof shall be investigated.

Access for maintenance purposes shall be provided to all plant and equipment situated on the roofs. This shall be provided by means of suspended steel walkways, stairways and ladders. Access routes shall be obvious and shall exclude the need to walk directly on the steel sheeting.

9.4.2.6 Walls

External elevations of all steel framed buildings shall be clad using a suitable plastic coated galvanized steel insulated sheeting system. Cladding to concrete frame buildings shall be in accordance with Architectural requirements.

Masonry panel walls shall be used as necessary within the buildings and built in steel posts shall be provided as necessary to provide lateral stability. The design and detailing of all masonry shall be in accordance with ACI 530.1 “Specification for Masonry Structures” and the Uniform Building Code 1997 (UBC). Special reinforcing details set out in the UBC for seismic zone in which the specified site falls shall be adhered to. It should be noted that there are no special construction detailing provisions for seismic zone 1.

9.4.2.7 Stairs

All common stairs within all building frame types shall be of reinforced concrete construction (unless the common stair is within a fire protected stair well). All stairs within RC

- 9.23 -


buildings shall be of RC construction unless otherwise approved by the Owner/Engineer. Stairways within steel framed buildings shall be either of RC or steelwork construction as appropriate.

9.4.2.8 Cranes, monorails and runway beams

In order to permit the lifting and transfer of major items of plant within the buildings and the removal off-site for maintenance or replacement purposes, overhead electrically operated travelling cranes (EOT), monorails and runway beams will be provided. Each hoisting facility will be designed for the heaviest component it will be expected to lift and remove for maintenance.

The hoisting facilities required are detailed in the mechanical specification Section 6.

9.4.3 Materials

All materials shall conform to the latest edition of the relevant American, British, Iraqi or International Standards cited within this Specification and within the design Standards referred to therein. Any materials not fully specified and for which there is not a relevant Standard shall be the best of their kind.

Samples of all materials for the Works may be called for at any time by the Owner/Engineer and shall be furnished by the Contractor free of charge and without delay. The cost of all routine tests required by the relevant British or other Standards shall be borne by the Contractor.

9.4.4 Civil design parameters

9.4.4.1 Design methodology

The Contractor shall adopt a design methodology which will identify all significant factors in the design and ensure that proper attention is given to each factor at every stage in the design process.

The Contractor shall prepare for the whole of the works and each discrete section thereof, Design Basis Statements. The Design Basis Statements which shall be made available within eight weeks of the Contract Award Date shall include, but not be limited to:

a. Foundation design concept

b. Loading conditions

i. Dead

ii. Superimposed

iii. Plant and equipment

iv. Wind

v. Seismic

vi. Thermal

- 9.24 -


vii. Electric overhead travelling (EOT) cranes

viii. Mono rails/runway beams

c. Load case combinations

i. In accordance with ASCE 7-98, Minimum Design Loads for Buildings and Other Structures and UBC 97

d. Steel structure design parameters

i. Design concept fixed, pinned, portal, braced

e. Concrete structure design parameter

ii. Design concept braced, unbraced, slender, short, shear walls, etc.

f. Concrete

i. Grade

ii. Cover

g. Reinforcement

i. Types.

The Design Basis Statement shall also clearly state the American Standards (or where no suitable American Standard exists the appropriate/specified British Standards or Codes of Practice) to be used for design and material specification applicable to the entire scope of civil works for the Contract.

The Contractor shall also prepare for the whole of the works and each discrete section thereof, Detailed Design Reports for submission in accordance with the Contract. To allow the Owner/Engineer adequate time to plan and complete review cycles of the various reports, the Contractor shall prepare and issue a timetable and register of the submittals required to fulfil the Contract. The Detailed Design Reports shall be set out under the following subsections:

i. Scope of design

ii. Design criteria

iii. References

iv. Materials and properties

v. Loads

vi. Loading

vii. Analysis and design

viii. Discussion and conclusions

- 9.25 -


ix. Appendices.

9.4.4.2 Loading

The following loads shall be considered in design. Where relevant, the appropriate Codes and basic design parameters are also given below:

a. Dead – in accordance with ANSI/ASCE 7-98 “Minimum Design Loads for Buildings and Other Structures” and more specifically BS 648.

b. Imposed – in accordance with ANSI/ASCE 7-98 “Minimum Design Loads for Buildings and Other Structures”. The Contractor shall determine the correct superimposed loading for all floor areas but a minimum superimposed floor load of not less than 5 kN/m2 shall apply to all plant related buildings. The Contractor shall determine the correct superimposed loading for all roof areas but a minimum superimposed roof load of 1 kN/m2 shall apply to roofs where no access other than maintenance is required and a minimum superimposed roof load of 1.5 kN/m2 shall apply to roofs where access is provided.

c. Wind – in accordance with ANSI/ASCE 7-98 “Minimum Design Loads for Buildings and Other Structures”. The basic wind speed for the specified site shall be determined by the Contractor, but shall not be less than 45 m/sec (This is a 3 second gust speed at 10 m above ground in Exposure C conditions, associated with an annual probability of occurrence of 0.02). Exposure category D shall be used in the design. This applies also to storage tanks.

d. Seismic – Iraq has a varying degree of seismic risk according to the location of the specified site. Areas close to Iran has a maximum risk and is equivalent to Seismic Zone 4 of UBC 1997 design code. A minimum Zone 1 shall be assumed if no such seismic risk has been recorded in the past. The zoning shall be determined according to the known risks. In the absence of any historical data the zoning classification for the specified site shall be scaled from the published charts of the Global Seismic Hazard Assessment Program of 10 per cent exceedance in 50 years, with published 4.8m/s/s peak ground acceleration of the chart corresponding to the Zone 4 in UBC 1997. Thus locations with 1.2, 2.4 and 3.6 m/s/s peak ground acceleration shall be Zone 1, 2 and 3 respectively.

e. Thermal – The Contractor shall be responsible for determining the correct thermal range for design purposes but the thermal range shall be not less than -10°C to +55°C taken as ±35°C for design purposes when assessing building movements and shall be not less than ±30°C when considering strength design. As many facilities are the outdoor type the design has to take into consideration of a black object under direct sunshine can attain a temperature of 75°C.

f. EOT Cranes – Generally, permanent lifting facilities are required for plant maintenance purposes for all items of plant where access excludes the use of temporary/mobile facilities and for certain items of plant where the expected maintenance is carried out on a frequent basis. See specific building description for EOT requirements. The allowable vertical deflection of a crane gantry girder

- 9.26 -


based on maximum static wheel loads shall not exceed span/600. The allowable horizontal deflection pf a crane gantry girder due to crane surge shall not exceed span/500 (based on top flange properties only).

g. Mono-rails/runway beams – Generally, permanent lifting facilities are required for plant maintenance purposes for all items of plant where access excludes the use of temporary/mobile facilities and for certain items of plant where the expected maintenance is carried out on a frequent basis. All mono-rails and runway beams shall be designed to BS 2853. Lifting blocks of 1 tonne capacity and over will be electrically operated.

h. Major pipework loads – plant specific load.

i. Global pipework loads – plant specific load.

j. Cables – plant specific load.

k. Plant loads – plant specific load.

l. Erection loading – plant specific load.

m. Installation loading – plant specific load.

n. Maintenance loading - plant specific load.

o. Miscellaneous maintenance/access platform loads - plant specific load.

N.B: Fifty (50) year return period values shall be used for environmental loading as appropriate.

9.4.4.3 Foundations and earthworks

Design and construction of foundations and earthworks shall be in accordance with the requirements set down in the following:

BS 6031: Code of Practice for Earthworks.

CP 2012 Part 1: Foundations for Reciprocating Machinery (machine foundations).

BS 8004: Code of Practice for Foundations (other general plant foundations and building foundations).

ASTM Standards applicable to earthworks materials and testing.

In addition the Specification for Piling and Embedded Retaining Walls, published by the Institution of Civil Engineers (ICE) shall be followed.

The Contractor shall state in his calculations the maximum permissible foundation movement that may be tolerated consistent with normal operation of the plant.

- 9.27 -


The design of the foundations for the gas turbines and other plant foundations subject to dynamic loads shall be in accordance with DIN 4024 : Part 1 (1988) “Machine Foundations” and CP 2012 : Part 1 “Foundations for Reciprocating Machines”.

All other plant foundations and building foundations shall be designed in accordance with the relevant British Standards.

In the design of plant foundations, due account should be taken of settlement criteria required by plant manufacturers.

Foundations shall be designed with a factor of safety of three (3) against bearing capacity failure of the subsoil and a factor of safety of two (2) against overturning and sliding unless otherwise agreed or instructed by the Owner/Engineer.

For normal loads, the foundation designs shall be based on a stress distribution of 100 per cent compression on the underside of the base (eccentricity of loading < L/6) and within the

allowable bearing capacity of the soil. For foundations with overturning moments, the following shall be satisfied:

a. Uniaxial bending: eccentricity < L/4

b. Biaxial bending: 70 per cent of the base area to be effective in compression

c. Allowable bearing capacity of the soil not to be exceeded.

9.4.4.4 Structural design Standards

The following Standards shall apply as appropriate:

a. AISC: Manual of Steel Construction – Allowable Stress Design – 9th edition

b. ACI 318M-99/318RM: Metric Building Code Requirements for Structural Concrete and Commentary

c. BS 8007: Design of Concrete Structures for Retaining Aqueous Liquids

d. Uniform Building Code (UBC) 1997

e. ASCE 7-98: Minimum Design Loads for Buildings and other structures

f. National Structural Steelwork Specification for Building Construction

g. BS 2853: Design and Testing of Steel Overhead Runway Beams

h. BS EN 12944: Paints and varnishes – corrosion protection of steel structures by protective paint systems.

i. BS EN ISO 1461: Hot dip galvanized coatings on fabricated iron and steel articles – specifications and test methods

- 9.28 -


9.4.4.5 Security

The Contractor shall fence off the site and take all reasonable precautions to safeguard the health and safety of all persons, whether or not they are his employees, from all construction and construction related activities. The Contractor’s proposals for security shall be submitted to the Owner/Engineer. The exact delineation of the Contractors Site shall be established and agreed with the Owner/Engineer prior to the commencement of the Works. Foundations for security and check-point installations shall be suitably designed against forced entries by motor vehicles. The contractor shall provide the security provisions of such nature to reflect the National Standard requirement to ensure no disruption to the safe operation of the power station. For general site security, surveillance and alarm alert requirements see also Section 8 of the Specification.

9.4.4.6 Roads and hardstandings

New hardstandings and access roads serving the proposed plant shall be integrated into the existing road network. The new permanent road system within the site shall be designed to allow for adequate access and emergency situations during operation and maintenance. The layout of the access roads and pavings serving the Plant including the Water Treatment Plant and Chemical Storage tanks etc shall be designed to allow safe manoeuvrability and hardstanding for all necessary deliveries.

All existing roadways and accesses to, and within the site shall be repaired to the state that they were in prior to the works commencing.

Temporary roads during construction period to be suitable for transporting and positioning plant and equipment.

Permanent roads shall be designed in accordance with Iraqi Ministry of Public Works and AASHTO/ASTM requirements, eg Guide for Design of Pavement Structures published by AASHTO, on the basis of a 25 year life. The Contractor shall supply justification for the number of standard axles to be used in the design. The Site speed limit shall be 10 mph (15 km/h).

The roads within the site areas shall be constructed between raised kerbs and graded to falls leading surface water into gullies or catchpits which will connect into the main drainage system. Main road construction shall typically be of crushed rock sub-base on compacted subgrade appropriate to the ground conditions, with Asphaltic Concrete paving, or concrete, wearing course as appropriate. Concrete paving shall be provided where oil or chemical spillages may occur. The Contractor shall supply justification for his design proposal to the Owner/Engineer prior to construction of any roads or hardstandings.

Major access roads shall be 7.3 m wide and shall include the necessary kerbs, drainage, road markings and signs. Radii shall be provided on turning areas and corners which are suitable for transporting heavy equipment and plant during the construction period as well as for all future maintenance needs.

Road markings and signs shall be in accordance with the requirements of the Ministry of Public Works Administration. Footpaths shall be of 1500 mm nominal width minimum and designed for an accidental wheel load of 20 kN. Footpaths shall be either precast concrete flags or asphaltic concrete paving.

- 9.29 -


Within the plant area height limit gauges shall be provided where height clearances are limited and in particular where there is danger from overhead lines.

Safety barriers shall be provided where there are exceptional local hazards or where specific plant protection is required. These barriers will be of the Armco or substantial bollard type and be removable.

Car parks shall be constructed to the same specification as permanent roads with the additional requirements specified below. A minimum capacity of 50 passenger vehicles shall be provided. All car parking areas shall be provided with temporary sunshades during construction with the final car park spacing requiring permanent sunshades.

The surface of the hardstanding shall be laid with falls to the drainage system. Care shall be taken during the construction that no materials enter the drainage system.

At the junction of the hardstanding and roads due to different thickness of foundations, precautions shall be taken to ensure that sub-surface drainage from the hardstanding does not have a detrimental affect upon the road foundations.

The Contractor shall take reasonable steps to maintain the free movement of traffic on any roads used by him to gain access to the Site. All roads shall be maintained free of any spillage from the Contractor’s vehicles.

The Contractor shall provide for all roads within the site as well as any access roads required both for temporary and permanent use. The access roads shall be properly connected to the existing roads on or outside the site boundary.

Temporary access roads of adequate standard shall be provided for site traffic of all contractors pending completion of the permanent road construction up to and including binder course.

Permanent access roads shall be provided from the main site roads to all plant and buildings. They shall be of suitable width and radius for the proper movement, installation and maintenance of plant.

Hardstanding areas around the outdoor auxiliary plant etc may be constructed from Asphaltic Concrete Paving, or Concrete, laid to falls leading storm water to gullies or catchpits.

Hardstanding around all chemical, fuel handling/storage areas/delivery areas shall be concrete slabs with suitable gully drains leading to oil interceptors or chemical tanks as appropriate.

Where required gravel areas shall consist of a 150 mm layer of 20 mm gravel on a geotextile membrane overlaying a compacted formation.

- 9.30 -


9.4.4.7 Drainage

The Contractor shall install the following drainage systems:

a. surface water drainage

b. foul water drainage

c. oil/water drainage

d. chemical waste water drainage.

General

The surface water and foul drainage systems shall be designed and constructed in accordance with the requirements of BS EN 752: Drain and Sewer Systems Outside Buildings to comply with the Iraqi local authority requirements.

Surface water that is contaminated with fuel or oil shall be sufficiently treated prior to disposal.

The system shall be designed for the maximum predicted coincident flows from the various sources of plant effluent. A schedule of plant effluents shall be prepared at the design stage by the Contractor indicating the source and type of effluent, peak and average flow rates and coincident flows under all conditions of normal operation, maintenance and emergencies.

Contaminated effluent shall receive appropriate treatment at the source of pollution before being collected and discharged to a drainage system or the sea. Facilities shall include for oil separation, chemical treatment and neutralization as appropriate. Permission to discharge to that system shall be obtained from the appropriate authority. Provision shall be made for the disposal of any effluents that can not be treated satisfactorily.

Every effort shall be taken to ensure that the risk of pollution is minimized. Provisions shall be made to bund all storage and all delivery areas shall have a suitable drainage gully to all sides to prevent spillages spreading to the surrounding ground.

The quality and type of pipe used in carrying plant effluent shall be adequate to resist any resulting corrosion.

The use of gravity drainage shall be maximized. However, pumping may be necessary over part of the system to raise invert level, provide a more economical alternative to deep construction works for long pipe runs or for final discharge elevation. The Contractor shall incorporate and detail lift chambers (pumps) into the drainage systems as appropriate.

Gradients in gravity pipelines shall be kept above the minimum recommended limits for given pipe sizes so as to ensure above minimum velocities and pipe self cleaning, thus reducing the potential for sedimentation within the drainage systems.

- 9.31 -


The upper layers of the site are composed of loose material that is prone to settlement. The Contractor shall ensure that pipe runs do not develop “backflows” due to settlement along their length, by making suitable allowance for differences in invert level between the start and end of any given pipe run e.g. between manholes, catch-pits, etc.

Where existing redundant drainage interferes with the new works for the OCGT power station it will either be removed, or where this is impracticable it shall be filled with suitable material to prevent structural deterioration, unauthorized use, ingress of ground water, infestation of rodents, etc.

Surface water drainage

The Contractor shall design and install a surface water drainage system that will effectively drain the site and discharge to an existing public storm water system or a designated soakaway agreed in advance with the owner. Before discharging into the outside system or sea, the surface water shall pass through an oil/water separator. The discharge from the oil/water separator shall contain no visible oil or grease, ie less than 10 ppm.

The capacity of the surface water drainage system shall be designed based upon a Design Storm Frequency of 1 in 10 years and Design Flooding Frequency of 50 years, or other criteria required by the Iraqi Local Authority regulations. The contractor shall pay special attention to the impact on the site drainage resulting from high intensity, short duration rainfall events which are known to occur. The size of the pipeline systems shall be designed in accordance with the Wallingford Procedure, or similar equivalent, calculated in accordance with BS EN 752: Drain and Sewer Systems Outside Buildings or similar American or Iraqi Standard.

The Contractor shall install a “cut-off” drain at the boundary if the terrain is likely to produce flooding to the OCGT area.

Catchpits shall be provided in the surface water drainage systems in areas where a high proportion of suspended material could occur in the run-off. In such cases the invert of the catchpit shall be at least 500 mm below the invert of the outlet pipe, increasing in depth with increased pipe diameter. The plan area of the catchpit shall be sufficiently large to reduce the velocity of the flow to allow solids to be deposited.

The design of the pipework shall be in accordance with the pipe manufacturer’s recommendations in respect of pipe grade, trench dimensions and pipe bedding and protection using the Simplified Tables of External Loads on Buried Pipelines, published by the Road Research Laboratories of the Department of Transport.

The surface water drainage system for roofs and paved areas shall be designed in accordance with BS EN 12056 and BS EN 752 or similar American or Iraqi Standard.

Side entry gullies shall be used for roads and horizontal gullies for parking and paved areas and the system should be designed for removal of trapped sand.

Roof drainage shall be collected via roof outlets and downpipes to gullies or inspection chambers at ground level prior to discharge to the main drainage system.

- 9.32 -


Manhole and chamber covers shall be heavy duty throughout.

Foul water drainage

The design of the foul water drainage system shall be in accordance with BS 6297, BS EN 752 or similar American or Iraqi Standards, and shall be based on the number of permanent members of staff.

The new drainage works shall be fully designed and constructed and shall be independent of any systems on the specified Power Station site. Foul water shall be treated by a proprietary package sewage treatment plant. Treated discharge from the plant shall meet the requirements of the responsible Iraqi Authority, before being discharged to a public foul drainage system, the river or the sea. Where no discharge outlet is available the treated liquid portion of the discharge shall be pumped to an evaporation pond.

Oily water drainage

Oily water drainage systems shall be provided for, but not limited to, the following areas:

• oil unloading areas adjacent to oil storage;

• oil and fuel storage compound drainage;

• oil filed transformer compounds;

• car parking areas;

• plant and equipment from which oil spillages could occur.

The Contractor shall design and install an oily waste water drainage system which will effectively drain all areas where oil spillages could occur. The design shall incorporate bunded areas, oil interceptors and traps. The quality of the effluent shall be acceptable in all respects to the Local Authority.

Bunds provided in transformer compounds, oil storage areas, lube oil tanks and such like shall have an impounding capacity 1.25 times the largest possible oil spillage that could occur.

The Contractor shall provide adequate facilities for the inspection and maintenance of oil interception equipment.

The oil interceptor shall be of adequate size to cater for an accidental total spillage of the largest transformer on site.

Chemical waste water drainage

The system shall be designed for the maximum predicted coincident flows from all sources of plant effluent. The Contractor shall prepare a schedule of plant effluents indicating the source and type of effluent, the peak and average flow rates and coincident flows under all conditions of normal operation, maintenance and emergencies.

- 9.33 -


The contaminated effluent shall receive the appropriate treatment before it is discharged.

The pipework, fittings etc, shall be fully designed and use the most appropriate materials to withstand the chemical composition and temperatures of the effluents.

When on off site facilities is available the chemical discharge shall be neutralized and pumped to an evaporation pond.

9.4.4.8 Buried pressure pipelines

Buried pressure pipelines for water mains, fire water mains and rising mains for drainage shall be designed in accordance with BS 8010 or similar American or Iraqi Standards. All pipelines carrying fuel oils shall be installed in sealed ducts to prevent ground contamination in the event of a pipework leak.

9.4.4.9 Buried services

Ducts and chambers for electrical, mechanical and telecommunication services shall be designed to the appropriate loading.

Chambers shall incorporate a drainage sump. Where practicable the sump shall be linked to the appropriate drainage system.

The Contractor shall allow for the relocation of any existing buried services.

9.4.4.10 Protection of structural steelwork

The following is indicative of the type of corrosion protection surface preparation and painting:

Main and secondary steelwork In accordance with Section 9.6 of this Specification.

Cladding rails and roof purlins (all areas)

Hot dip galvanized fixed with spun galvanized or sherardized bolts or alternatively in accordance with Section 9.6 of this Specification

Where fire protection is required this shall be by an intumescent paint system in exposed situations (subject to required fire rating being achievable) or, where concealed, a fire resistant board system will be acceptable.

9.4.4.11 Marine works

Any works, such as those associated with the surface water or foul water discharge outfalls, that may be affected by the marine environment shall be designed in accordance with BS 6349: Maritime Structures or similar American or Iraqi Standards.

- 9.34 -


9.5 Specific building and architectural requirements

9.5.1 Cladding and decking

9.5.1.1 General

Notwithstanding the following outline Specifications, cladding and roof decking shall be chosen, designed, detailed and constructed to achieve the thermal and acoustic requirements for the plant and building operation and the air and vapour movement requirements for the total building fabric.

The design of the individual buildings and their relationship to each other shall take account of the requirements for compliance with the relevant sections of the fire legislation in force in Iraq.

The Contractor shall complete the design of the cladding system in accordance with the relevant codes of practice and insurers requirements, and coordinate the design and detailing of the cladding system with all related works.

The external fabric of the building is required to give a durable, economical and easily maintainable form of construction which is responsive to the prevailing weather conditions. Due consideration shall be given to the durability against erosion by sand storms and blocking up of the services by trapped sand.

The building fabric shall ensure that environmental conditions within the buildings can be maintained within the prescribed limits with the minimum energy use to fully comply with building legislation.

Very high surface temperatures can be experienced on all faces of the buildings. Because of the high insulation value of the wall and roof construction which will not allow a high heat transfer to the inside of the building from the external surface of the panels, all wall and roof finishes shall be light coloured with high reflective values to minimize the build up of surface temperatures on the external face of the panels. The panel system proposed therefore shall have test certificates to prove that it has been tested to the maximum surface temperatures which are likely to be experienced at site without any delamination or deterioration affects on the panels or their joints over the required lifetime of the building.

The wall and roof cladding shall be designed and installed to comply with the manufacturers requirements to obtain a 30 year guarantee on the completed roofing and walling.

9.5.1.2 Metal wall cladding

Wall cladding shall consist of factory manufactured sandwich panels with a minimum 0.5 mm thick external sheet and a 0.4 mm thick inner sheet. The void between the sheets shall be fully filled as part of the manufacturing process with CFC free rigid polyurethane insulation fully bonded to the inner surfaces of the outer and inner sheets.

The panels to be used shall have a profile approved by the Owner/Engineer. The panels shall be manufactured to external and internal colours approved by the Owner/Engineer.

- 9.35 -


The external and internal panel finishes shall be selected to achieve the specified guaranteed life expectancy. All flashings, trims, cappings etc shall have the same finish as the panels. All cladding should be resistant to ultra-violet degradation and all colour coatings should have a high fade resistance.

The panels shall be of a design for secret fixing.

The inner face of the sandwich panels shall act as the vapour barrier. A full seal shall be provided between all panels in accordance with the manufacturers instructions to achieve continuity of the vapour barrier. The vapour barrier shall be integrated with, continuous, and sealed to the vapour barrier in the roof system, the plinth wall and all components built into the fabric of the building.

The wall cladding system shall achieve a ‘U’ value of 0.25 W/m2K or better, based on an aged thermal conductivity of 0.020 W/mK, and a minimum 80 mm thickness of insulation shall be used. The detailing of all junctions and interfaces shall ensure that there is continuity of the insulation value across the whole exterior of the building.

Allowance shall be made for the provision of spacers at fixing points to achieve a true line in the sandwich panels.

9.5.1.3 Metal roof cladding

Roof cladding shall consist of factory manufactured sandwich panels with a minimum 0.5 mm thick external sheet and a 0.4 mm thick inner sheet. The void between the sheets shall be fully filled as part of the manufacturing process with CFC free rigid polyurethane insulation fully bonded to the inner surfaces of the outer and inner sheets.

The panels to be used shall have a profile approved by the Owner/Engineer. The panels shall be manufactured to external and internal colours approved by the Owner/Engineer.

The external and internal panel finishes shall be selected to achieve the specified guaranteed life expectancy. All flashings, trims, cappings etc shall have the same finish as the panels. All roof cladding should be resistant to ultra-violet degradation and all colour coatings should have a high fade resistance.

The panels shall be of a design for secret fixing.

Wherever possible, the sandwich panel shall be in a single length from ridge to eaves except where interrupted by a roof ventilator or other penetration.

The inner face of the sandwich panels shall act as the vapour barrier, and require to be fully sealed between panels in accordance with the manufacturers instructions to achieve continuity of the vapour barrier. The vapour barrier shall be integrated with, continuous, and sealed to the vapour barrier in the wall system and all components built into the fabric of the building. Anti condensation tape shall be provided where recommended by the manufacturer.

The roof cladding system shall achieve a ‘U’ value of 0.25 W/m2K or better, based on an aged thermal conductivity of 0.020 W/mK, and a minimum 80 mm thickness of insulation shall be

- 9.36 -


used. The detailing of all junctions and interfaces shall ensure that there is continuity of the insulation value across the whole roof and its junctions with the walls and any built in components.

Where rainwater gutters form part of the roof covering, they shall be fully sealed and have the same U value as the remainder of the roof.

The design of the roof structure, finishes and accessories shall ensure that deposits of wind blown sand and dust, which can build up on roof areas behind parapets and projections through the roof, can be dealt with, and all rainwater pipe connections shall be easily accessible to allow them to be cleaned.

9.5.1.4 Support for cladding

Before the installation of roof and wall panels, the bearings shall be checked to ensure they are straight and to an even and correct line and gradient. Adjustment shall be made where necessary to ensure consistency of line and continuity of support, and spacers shall be utilized to ensure the correct alignment and bearing is achieved where adjustment of the main support cannot be achieved.

9.5.1.5 Fixings

The panels shall be fixed to steel support beams with high threaded type, grade 304 austenitic stainless steel, self tapping screws in a manner recommended by the manufacturer. The complete fixing screw shall be stainless steel.

All wall and roof panels shall have secret fixings. Fixings for flashings, trims etc. shall be complete with or shall have integral colour matched caps or heads.

Fixing of sheeting, flashings and cappings etc shall be by self drilling or self tapping stainless steel screws of size recommended by the manufacturer.

Fixing of brackets, straps etc to cappings shall be by stainless steel screws, with countersunk heads where appropriate.

Additional fixings, saddle washers and cover caps shall be provided if deemed necessary where high suction loads can be experienced.

The whole of the works shall be carried out in accordance with CP 143 Part 10: 1973 and shall provide a completely weathertight enclosure.

9.5.1.6 Flashings

All external flashings shall be formed from a minimum 0.7 mm thick metal, and shall be fully weather sealed at all edges. All flashing, trims and cills associated with wall and roof cladding shall be the same colour as the cladding to which they are fixed. All flashings, trims, cappings etc. shall have the same finish as the panels.

- 9.37 -


External flashings shall be detailed, installed and fully sealed to fully close off any potential air, noise or water transmission path. Internal flashings and trims shall be detailed and sealed to maintain the integrity of the vapour barrier.

Prior to the installation of the second side flashing or trim, the space between inner and outer flashings shall be fully filled with insulation to maintain the same insulation value as the walls and roof.

9.5.1.7 Caulking compound and sealing strip/gaskets

All sealants of whatever form shall be to the recommendations of the cladding manufacturer, and they shall be located and installed in accordance with their instructions.

Separation strips between panels and substrate shall be provided in accordance with the panel manufacturers recommendations.

9.5.1.8 Panel glazing

Glazing panels of the same profile as the sheeting may be incorporated into the wall and roof cladding. Where these are specified, they shall be double glazed and meet the requirement of Fire Codes, to ensure that the fire rating and structural requirements are maintained.

9.5.1.9 Windows

Windows incorporated into the external wall cladding shall be of a colour approved by the Owner/Engineer. They shall comply with BS 6375 Part 1 for an exposure category 1600. All window frames shall incorporate a thermal break and internal voids in the frames shall be filled with insulation to prevent heat transfer.

Windows shall be complete with all flashings and shall be fully sealed to substrate.

The vapour barrier shall be fully sealed to the windows.

All windows shall be glazed with solar reflective glass with a low heat transfer value in double glazed units.

9.5.1.10 Solar shading

All glazed areas which can be subject to direct sunlight at any time of the day throughout the year shall be provided with external shading. Areas of both horizontal and vertical shading shall be provided to cope with the angle of the sun anywhere on its path. Solar shading shall be formed by a fixed system.

9.5.1.11 Louvres

All external louvres built into the external cladding shall have an in-built sand trap, and the louvre frame shall be fully sealed to the surrounding construction.

- 9.38 -


9.5.1.12 Safety systems

Adequate means of access shall be provided to the roof of buildings for maintenance of any equipment located there. Where access is provided, either parapets or a full safety system shall be installed for the protection of maintenance personnel. Any safety system provided shall be fixed in such a way that it does not reduce the integrity of the roof finish.

9.5.1.13 Roof drainage

The roof drainage system shall be designed and detailed to cope with the calculated maximum rain requirement. Where rainwater gutters form part of the roof covering, they shall be fully sealed and have the same U value as the remainder of the roof. Supports for the rainwater gutter shall be fully integrated with the roof and wall cladding.

Rainwater pipes shall be aluminium or galvanized mild steel, medium gauge to BS 1387: 1967 suitable for screwing to BS 21 pipe threads. All rainwater pipes shall be routed internally. Pipes shall generally be straight and plumb fixed with brackets to structural steel columns. They shall be complete with suitable bends for connection to outlets and to drainage.

Jointing compound where required shall be to approval. Inspection covers shall be provided, suitably sealed, to all pipes immediately above ground floor level.

9.5.1.14 Movement

The design, detailing and fixing of the roof and wall cladding, and all trims, cappings and flashings shall make allowance for the calculated movement of the building and cladding due to wind loads and thermal expansion and contraction. Allowance shall be made for movement across the whole structure, fabric and finishes of the buildings to cope with the calculated maximum thermal movement of all the elements of the buildings. This shall also be considered in conjunction with the calculated maximum structural movement due to wind loading.

Allowance shall also be made for the movement of elements of the construction which will require joints at closer centres as required by the relevant codes of practice.

9.5.1.15 Standards

The panels shall have a Class 0 surface, in accordance with BS 476 Parts 5 and 6 1968 and Part 7 1971, and roof panels shall be rated AA when tested to BS 476: Part 3: 1975.

The roof and wall cladding systems shall be designed in accordance with CP3, CP143, BS 5427, BS 6399 and BRE Report 143. Calculations shall be provided to prove the adequacy of the roof and wall cladding, its complete support systems and all fixings.

9.5.1.16 Acoustic requirements

Specific requirements are stated for the maximum increase in noise levels from the completed buildings and these shall be taken into account in the design and detailing of the cladding and roof systems to ensure that the target noise levels are achieved.

- 9.39 -


9.5.1.17 Cutting

If hole cutting is required on site to accommodate penetrations, this shall be done using a motorized disc cutter and/or hole saw or nibbler. Acetylene cutting shall not be allowed. Suitable flashings of material and finish to match the main sheeting or, where appropriate, soaker sheets shall be provided incorporating welded upstands etc.

9.5.1.18 Verification of performance

The Contractor shall submit evidence and calculations demonstrating compliance of the design with performance requirements before commencing fabrication of any part of the cladding. All submitted information shall be based on approved laboratory testing or computer modelling.

9.5.1.19 Product delivery, storage and handling

All cladding components shall be protected, transported and handled in accordance with the manufacturer’s instructions, to avoid damage by distortion or by impact damage to finishes. Bundles shall be lifted using ropes or chains with slings positioned correctly to minimize pressure/distortion across or along the sheets. When removing individual sheets from bundles they shall be lifted directly and not dragged.

9.5.1.20 Detail drawings

The Contractor shall submit detail drawings of the work in this section for approval by the Owner/Engineer. These drawings shall include complete scale and full size details of all cladding components, showing the relationship to and integration with adjacent building elements, the points to which dimensions are taken and all fixing proposals.

9.5.2 Metal doors and frames

Fire resisting internal and external metal doors and frames shall be constructed from galvanized steel conforming to BS 476: Part 8: 1972 for test methods and criteria for the fire resistance of elements of building construction. The fire rating shall be 2 hours, and the Contractor shall provide evidence of this performance by test certificate or assessment by an approved authority to the Owner/Engineer before manufacture.

All external door frames shall incorporate a thermal break and internal voids in the frames shall be filled with insulation to prevent heat transfer across the frames.

All door frames shall also incorporate spacers at the fixing points to prevent distortion.

All doors shall be complete with ironmongery including stainless steel hinges, handles, bolts, closers, locking arrangements, and where appropriate emergency escape facilities. Locking shall adopt a Site Master Key system to be agreed with the Owner/Engineer.

Doors provided solely as a means of escape shall be fitted with panic bars and shall not be openable from the outside.

- 9.40 -


Reinforcement of the metal shall be provided at all fixing points for ironmongery on the doors and frames.

Personnel doors shall be to approval. Hinges shall be stainless steel.

Folding shutter doors shall be electrically operated with manual override, automatic stop facility and automatic closing facilities where fire resistance is required.

They shall be provided by an approved supplier.

All external doors shall achieve at least the same acoustic requirements as for the walls.

The junction of the door frames with the surrounding wall shall be detailed to eliminate any potential noise, vapour or fire path.

All exposed surfaces of doors, frames and trims shall be shop primed and painted on site.

The Contractor shall submit to the Owner/Engineer, for his approval before manufacture, copies of drawings showing construction of doors and frames and their junction with surrounding wall construction.

Doors and frames shall be protected from distortion during transit, handling and storage.

Doors and frames shall be provided with protective coverings which shall be retained in position for as long as possible.

9.5.3 Internal doors and frames

If agreed with the Owner/Engineer that internal doors and frames should not be metal, they shall be of an approved hardwood. Unless otherwise specified, the frames shall be screwed and pelleted to pallets or wedged and screwed and pelleted to grounds. Architraves and stops shall be hardwood with mitred joints. A seal shall be provided between the architrave and surrounding wall. The doors shall have fire resistance in accordance with International Building Code 2000.

Architraves shall not be fixed until after the wall finish has been formed unless otherwise specified.

Vision panels shall be incorporated into fire doors with hardwood beads detailed so as not to compromise the required level of fire rating. Glazing shall be to the requirements International Building Code 2000.

All doors and frames shall be to the approval of the Owner/Engineer. Where these are required to be fire resisting, the combined door/frame construction shall provide the necessary fire rating when tested to BS 476 Part 8(1) 1972. A certificate of compliance shall be provided by the manufacturer and submitted to the Owner/Engineer by the Contractor.

- 9.41 -


Fire resisting doorsets shall be installed in a manner to ensure continuity of the fire resistance between the frame and the surrounding fire wall. The junction of the door frames with the surrounding wall shall be detailed to eliminate any potential noise, vapour or fire path.

All doorsets shall be complete with ironmongery including stainless steel hinges, bolts, locking arrangements, closers, handles and where appropriate, emergency escape facilities. Locking shall accord with the Site Master Key system to be agreed with the Owner/Engineer.

All doors shall include blockings for the fixing of ironmongery.

Doorsets shall be kept under waterproof cover during transit and be stored on Site in dry protected conditions. They shall be handled and stacked carefully to avoid distortion or damage. Protective coverings shall be retained in position for as long as possible.

9.5.4 Internal vision panels

Vision panels in internal masonry walls shall be of a design to match the doorsets in the relevant room. Where appropriate the fire rating shall be the same as that of the wall in which they are situated and glazing shall comply with the requirements of Regulations for the location of the vision panel.

9.5.5 External walling

All buildings are to be constructed with an external plinth wall a minimum height of 2.1 metres above ground level. The exact height shall be determined to suit the external architectural treatment of the buildings, and the requirements of the plant layout internally.

The design of the wall shall incorporate insulation to achieve the same U value as the remainder of the external wall, and a vapour barrier shall be provided which is integral with the vapour barrier of the surrounding construction.

The wall must incorporate a damp proof course which is bonded to the damp proof membrane in the floor construction.

The plinth wall shall include all necessary stabilizing measures to satisfy structural requirements.

The external finish of the plinth wall shall be agreed and an appropriate specification shall be submitted for comment/approval by the Owner/Engineer.

The Contractor shall submit to the Owner/Engineer details of the proposed design of the walling and its junctions with all surrounding elements.

The design and detailing of the plinth wall shall take account of noise level requirements to ensure that the target noise levels are achieved.

- 9.42 -


9.5.6 Internal masonry walling

Internal masonry walls shall be constructed in dense concrete blocks. These shall be fairface blocks built fairface where exposed in final construction. The blockwork shall be finished with two coats plaster and painted, in all areas with suspended ceilings, and the remainder shall be fairfaced, sealed and painted.

Necessary measures shall to be taken to ensure structural stability of free standing masonry walls. Vision panels shall be provided in masonry walls where they are required to satisfy operational requirements.

In office areas, the blockwork shall be provided full height, or to minimum of 150 mm above the false ceiling where one is provided, on the external walls, and finished to match other internal walls in office areas. The complete construction of external walls shall have a ‘U’ value of 0.25 W/m2K or better.

The Contractor shall submit for approval all details of brickwork and blockwork to be used on the project.

9.5.7 Suspended ceilings

9.5.7.1 General

Suspended ceilings shall be installed to all circulation areas, toilets, control rooms, offices and the like, with recessed light fittings used in all such areas. The ceilings generally shall be a lay-in grid system, of a type and manufacturer approved by the Owner/Engineer. A plain thermal tile or equivalent approved shall be used in toilet areas.

9.5.7.2 Workmanship

All suspended ceilings shall be erected in accordance with the manufacturer’s instructions and, where applicable, in accordance with the requirements of CP 290:1973.

9.5.7.3 Storage and protection

All materials shall be transported and stored on a smooth flat base to prevent distortion and shall be kept dry.

All materials shall be stored in temperature and humidity conditions similar to those in areas where they are to be finally fixed.

All materials shall be protected from damage and soiling, with protective coverings retained in place for as long as possible.

9.5.7.4 Other trades

Allowance shall be made for the installation of light fittings, extract fans and any other ceiling penetrations by other trades as applicable.

Light fittings and ventilation ductwork shall be supported independently of the ceilings.

- 9.43 -


The Contractor shall plan the erection and method of ceiling suspension in conjunction with the layouts of electrical and other services in other sections of this Contract. The ‘first fix’ work on electrical services shall be completed before the suspended ceilings are erected.

Ceiling tiles, electrical and other components shall be entirely compatible in all respects.

9.5.8 Damp proofing

The design of the floor construction shall incorporate a damp proof membrane over the complete area. The damp proof membrane shall be fully lapped and sealed at all joints and at all penetrations through the membrane. The damp proof membrane shall be continuous round all pits, channels and downstands in the substructure.

The damp proof membrane shall be lapped and be fully bonded to a damp proof course in the plinth wall if this is not built from the top of the slab.

The design and installation of the damp proof membrane shall fully comply with the requirements of International Building Code. The Contractor shall submit proposals for the type and detailing of all damp proofing for comment/approval by the Owner/Engineer.

9.5.9 Stairs

Where the design of the buildings requires stairs to be provided, these shall comply with the requirements for means of escape for personnel, and the stairs and balustrading shall be designed to satisfy the detailed requirements of the applicable legislation.

The Contractor shall submit his proposals for the design of stairs and balustrading and/or handrails for comment/approval by the Owner/Engineer.

9.5.10 Sanitary ware

The detail design of the buildings shall allow for the provision of sanitary facilities to satisfy the appropriate standards for both male and female staff. The proposals for the detailed layout of the sanitary areas and the selection of fittings shall be submitted to the Owner/Engineer for approval/comment. In assessing the sanitary requirements, the Contractor shall assume a maximum on-site presence of approximately [15] personnel.

9.5.11 Finishes

9.5.11.1 General

All finishes for floors, ceilings, walls, skirtings, window cills, worktops, casings and fittings shall be appropriate for the area in which they are to be used.

The Contractor shall submit his specifications/proposals for all internal finishes and colours in all areas of each building for approval by the Owner/Engineer. The Contractor shall prepare sample boards to show his proposals for certain areas of the buildings to be selected in agreement with the Owner/Engineer.

- 9.44 -


9.5.11.2 Definitions of finishes

All paint finishes shall be such as to completely cover and obscure the base construction and priming coats such that additional coats of paint will not effect a significant improvement.

All paint finishes shall be consistent in colour and free from brush marks and all irregularities and defects in the paint surface.

Filling, stopping, knotting, grain filling and rubbing down between coats shall be carried out on surfaces as required.

All finishes shall be washable with warm water containing mild detergents without affecting the finish.

Drying times shall be such that dust contamination of the finished surface is kept to a minimum consistent with a good hard gloss finish.

All finishes shall be of the correct type to withstand the various conditions under which the painting system shall operate.

9.5.11.3 Schedules

Colour/finishes schedules shall be provided by the Contractor showing his proposals for all surface finishes, both site and factory applied, and submitted for comment/approval by the Owner/Engineer.

9.5.11.4 Painting - General

Paints for priming, undercoating and finishing shall be ready mixed paints. All paints shall be supplied by an approved manufacturer who shall certify that the paint is suitable for the intended purpose. All coats of paint to give the required full application shall be manufactured by the same manufacturer.

Knotting for the preparation of joinery for painting shall comply in all respects with current Standards.

The colours of paints shall be approved by the Owner/Engineer on submission of the colour/finishes schedules.

Any softwood timber shall be treated in accordance with either BS 4072, BS 5082, BS 5589 with approved preservatives. All untreated timber surfaces exposed by cutting the timber for fitting into the building shall be thoroughly treated by dipping, spraying or brushing those surfaces with the same type of preservative used for the original application, and as approved by the Owner/Engineer.

All work shall be properly cleaned and rubbed down between each coat in a way, and using materials, recommended by the manufacturers of the paints concerned. No coat shall be commenced until the previous coat is dry, hard and satisfactory. Each coat shall be of a distinct colour from the preceding one, and all colours shall be approved by the Owner/Engineer. All paint

- 9.45 -


shall be applied in accordance with the manufacturer’s recommendations and shall not contain more than the minimum quantity of thinners or dispersers necessary to permit the satisfactory application of the paint. Spray painting will not be permitted except for internal faces of walls and ceilings. All other paint shall be thoroughly brushed into, and completely cover, the surfaces.

9.5.11.5 To hardwood generally (including veneered doors)

Preparation shall include the removal of all traces of dirt, oil, grease or any other matter which may affect the painting process. Any holes, cracks or other surface defects shall be filled with an appropriate filler to obtain a smooth surface, knot, prime, stop, fill pores and re-sand to achieve a smooth surface ready for undercoating. Aluminium based primer shall be used.

Apply two undercoats alkyd based paint of approved manufacture, and finish with one coat alkyd based gloss finishing paint by the same manufacturer. Colours shall be from the BS 4800 range.

9.5.11.6 To hardwood thresholds

Preparation shall be as for other hardwoods to a smooth sanded finish and application of three coats approved polyurethane one pack flooring grade eggshell varnish rubbing down between coats.

9.5.11.7 To blockwork and plasterboard surfaces

Preparation shall be according to approved practice, and application of one sealing coat matt emulsion paint with fungicidal additive and two finishing coats of approved silk vinyl emulsion paint.

9.5.11.8 Removal of fittings and ironmongery

All fittings, door furniture, ironmongery, plates and labels shall be removed before painting, carefully labelled as to their exact location and replaced on completion in clean condition to the requirements of the Owner/Engineer.

9.5.11.9 Masking

Where spray painting is permitted, attention shall be given to taping and masking adjacent and related surfaces for protection.

9.5.12 Flat roof waterproofing systems (if required)

9.5.12.1 Roofing materials

The roof waterproofing system shall incorporate a vapour barrier, insulation to achieve a U value of 0.25.W/m2C or better and a waterproof membrane by an approved supplier.

The roofing system shall incorporate aluminium or galvanized mild steel bent plates, to parapet upstands, galvanized to BS 2989 : 1982, Grade G275.

- 9.46 -


9.5.12.2 Application

The greatest care shall be taken to avoid damage to roof coverings at all stages of the work and any damage caused thereto shall be made good to the entire satisfaction of the Owner/Engineer at the Contractor’s expense.

Before laying any part of the roof waterproofing system care shall be taken to ensure that the deck, vapour barrier, insulation and preceding layers are completely dry. No part of the system shall be laid in wet or otherwise unsuitable weather conditions and adequate measures shall be taken to prevent water penetration to the existing rooms during roofing operations.

All roof finishes shall be guaranteed for a minimum period of ten years, in respect of both necessary repairs to the roofing system and also resultant repairs to finishes and fabric caused by any failure of the roofing system as a result of either faulty workmanship and/or faulty or inappropriate materials. A written document to this effect shall be supplied to the Owner/Engineer prior to the acceptance.

All work shall be reviewed by the Owner/Engineer and samples of materials to be used shall be submitted for review, prior to roofing work commencing on Site.

On completion all surplus materials are to be removed and the whole area left in a neat and tidy condition.

9.6 Materials and workmanship

9.6.1 Codes and Standards

Civil construction activities shall be carried out to the relevant American Standards or British Standards and Codes of Practice, or any local Iraqi Standards found to be more applicable in terms of materials and workmanship.

The latest edition of such documents shall be used, including all current amendments and additions.

9.6.2 Materials

Samples, technical descriptions and sources of supply of materials shall be submitted where required by the Specification to the Owner/Engineer.

9.6.3 Certification of materials

Two copies, one to be submitted to the Owner/Engineer, of a certificate verifying that the materials meet the specified requirements shall be obtained by the Contractor with each delivery of materials together with the results of any tests on such materials that are required by the Specification and the relevant British Standards. The Contractor shall submit to the Owner/Engineer a statement detailing his test procedures and testing schedule for Site manufactured materials.

- 9.47 -


9.6.4 Storage of materials

Materials shall be stored to preserve their quality and condition in a manner which complies with the manufacturer’s particular requirements.

9.6.5 Plant and equipment

The Contractor shall provide details of plant and equipment to be used in the construction of the civil works including his proposed construction cranage strategy.

9.6.6 Concrete

9.6.6.1 General

The minimum requirements for concrete work are specified in this section. Notwithstanding these requirements the Contractor shall provide a durable concrete, fit for purpose in terms of strength and serviceability, and wholly adequate to protect concrete against the harsh soil conditions.

Durable concrete shall be defined as concrete that remains free from major maintenance and repair and which provides protection against reinforcement corrosion during the intended design life of the structure.

Concrete structures shall be designed for a minimum design life of 40 years.

The minimum compressive (cylinder) strength of structural concrete as defined in accordance with ACI 318 shall be 35 N/mm2.

The Contractor shall establish by Site Investigation the aggressive chemical environmental conditions for concrete exposure. Concentration levels of surface, airborne and below ground chloride and sulphate salts and any other aggressive chemical agents shall be determined. The chemical composition of below ground sulphate composition and concentrations shall be established to a degree of accuracy compatible with the limits specified in BS 5328.

The Contractor shall, as a minimum requirement, comply with the concrete mix design parameters specified below.

If it is deemed necessary by the Contractor to enhance the concrete mix design parameters in order to achieve the intended design life, then the Contractor shall specify additional protective measures over and above those specified. Additional protective measures include (but are not limited to) cement replacement/addition, reinforcement coatings, chemical admixtures, surface membranes and lining systems. The additional protective measures can be a combination of several provisions and the incorporation is mandatory in the contract. The cost of any such additional measures shall be deemed to be included in the Contractors offer. The Contractor shall demonstrate to the satisfaction of the Owner/Engineer that the intended design life can be fulfilled.

Compliance with the concrete mix design parameters specified below shall not relieve the Contractor of his responsibility to determine his own concrete mix design, to fulfil the contract requirements.

- 9.48 -


During the detailed design stage and following field trial analysis and subject to the agreement of the Owner/Engineer the Contractor may propose alternative concrete mix designs to satisfy the contract requirements.

The Contractor shall be responsible for ensuring that all constituent materials used for the concrete works (eg cement, aggregate, reinforcement, etc) comply with recognized international material standards and methods of testing and meet the requirements of this Specification. The use of proposed constituent materials shall be agreed with the Owner/Engineer prior to their use on the Project.

Trial concrete mixes shall be carried out prior to construction. Tests on fresh and hardened concrete shall be carried out to demonstrate trial mixes satisfy the requirements of this Specification. Concrete mix designs shall be agreed with the Owner/Engineer prior to construction.

During construction regular tests shall be carried out on the concrete mix constituents, fresh concrete and hardened concrete. Tests shall be carried out to meet the requirements of this Specification. The Contractors proposed testing schedules shall be submitted and agreed with the Owner/Engineer prior to construction.

Constituent materials, and test methods for materials, fresh concrete and hardened concrete shall comply with ASTMS, British BSI, or German DIN Standards.

9.6.6.2 Concrete mix design parameters for reinforced concrete

Cement 30 per cent/70 per cent combination of Portland cement and ground granulated blast furnace slag (ggbs)

Minimum ggbs/cement content

Silica fume as cement replacement

400 kg/m3 (120 kg/m3 OPC + 280 kg/m3 ggbs)

8 per cent minimum

Maximum water cement ratio 0.4

Durability enhancing admixture 10 litre/m3 of calcium nitrite corrosion inhibitor

9.6.6.3 Concrete mix design parameters for plain concrete

Cement Sulphate resisting cement (ASTM Type V)

Minimum cement content 400 kg/m3

Maximum water cement ratio 0.4

9.6.6.4 Cement

Cements shall comply with ASTM C150.

- 9.49 -


9.6.6.5 Cement Replacement

Cement replacement shall comply with:

a. GGBS (blast furnace slag) to ASTM C989 or BS 6699

b. Pulverized fuel (fly) ash to ASTM C618

c. Silica fume (microsilica) to ASTM C1240 (maximum 10 per cent replacement).

9.6.6.6 Aggregates

Aggregates shall comply with ASTI C33 except as modified below.

Maximum chloride content of aggregate should be limited to 0.02 per cent by dry weight.

The potential for alkali-aggregate reactivity shall be investigated in accordance with ASTM C277/C289.

9.6.6.7 Water

Water used in the concrete mix shall be potable and free from deleterious substances and shall comply with BS 3148 or similar American Standard. Furthermore, the water quality shall not exceed the following limits:

a. Iron shall not exceed 0.25 ppm

b. Sulphate and chloride content shall not exceed 300 ppm

c. Total dissolved solids shall not exceed 500 ppm.

9.6.6.8 Reinforcement

The characteristic strength of the reinforcement fy should be 60,000 psi (equivalent to 413 N/mm2).

Reinforcement should be deformed steel conforming to ASTM A615 and A615A, Grade 60.

Epoxy coating for corrosion protection should be fusion bonded in accordance with ASTM A774A/A775M-92.

9.6.6.9 Admixtures

Admixtures shall comply with ASTM C494.

9.6.6.10 Coatings

External coatings to concrete shall comply with ACI 515.1R.

- 9.50 -


9.6.6.11 Limits for total chloride and sulphate content

ASTM test method C1012 shall be used to evaluate the sulphate resistance of mixtures using combinations of cementitious materials.

Maximum chloride (Cl) content by percentage weight of cement shall be limited to 0.15 per cent.

Maximum sulphate (SO3) content by percentage weight of cement shall be limited to 4 per cent.

9.6.6.12 Formwork

Formwork shall comply with ACI 347R.

9.6.6.13 Transportation

Concrete shall be measured, mixed, transported and placed in accordance with ACI 304 and as follows.

Concrete placement temperature shall not exceed 32°C.

9.6.6.14 Curing

Water curing methods shall be adopted unless approved otherwise by the Owner/Engineer.

Curing shall also comply with the requirements of ACI 308 Standard Practice for Curing Concrete, ACI 308.1 Standard Specification for Curing Concrete and ACI 305R, Hot Weather Concreting.

Water curing shall be for a minimum of 10 days.

9.6.6.15 Concrete cover

The minimum cover to reinforcement in buried concrete, or concrete exposed to seawater, or spray, shall be 75 mm.

For other external conditions of exposure the minimum reinforcement cover shall be 60 mm.

For internal conditions of exposure minimum reinforcement cover shall be 40 mm.

Tolerance on concrete cover shall not exceeded 10 mm of the values quoted above.

9.6.6.16 Quality control

The execution of the concrete works, including the field quality control and performance testing should conform to all the requirements of ACI 301, Specifications for Structural Concrete for Buildings.

- 9.51 -


The recommendations of BS EN 206-1: 2000 should also be followed where found to be relevant to specifying good concrete practice for middle east concrete.

To ensure the durability of the concrete, samples shall be tested to meet the following criteria:

h. ASTM C642: Standard Test Method for Density, Absorption and Voids in Hardened Concrete

ii. Water absorption <4%

iii. Permeable voids <10%

i. DIN 1048: Testing Concrete:

iv. Water Penetration <15 mm

j. BS 1881, Part 122: Methods of Testing Concrete

v. Water absorption < 2% (<1% for structure in contact with sea water)

k. AASHTO T277/ASTM C1202: Standard Test Method for Electrical Indication of Concrete Ability to Resist Chloride Ion Penetration

i. Chloride permeability < 1000 coulombs.

9.6.7 Setting out and monitoring

All survey, setting out and levelling shall be carried out in accordance with BS 5964 using instruments and equipment which shall be regularly checked and calibrated.

Information regarding site datum levels and co-ordinates may be provided by the Owner/Engineer.

Setting out stations shall be accurately positioned at locations to be agreed with the Owner/Engineer and shall be adequately protected from damage during the construction of the Works.

The Contractor shall carry out an accurate survey of all setting out stations relative to the site datum and shall submit details of their co-ordinates and levels to the Owner/Engineer for agreement prior to commencing any setting out of the Works.

All subsequent survey and monitoring work shall be based upon the setting out stations and shall record details of the reference station used.

Monitoring for movements of ground or structures shall, if required by the Owner/Engineer, be carried out by the Contractor at locations and frequencies as instructed by the Owner/Engineer.

- 9.52 -


All surveys and setting out work shall be fully recorded and the details and results provided to the Owner/Engineer on completion of each section of the Works.

9.6.8 Earthworks, excavation and filling

Materials, workmanship and testing procedures shall be in accordance with the appropriate ASTM or AASHTO Standards and procedures. The Contractor shall submit a document outlining his proposed materials and field testing regime which shall be agreed with the Owner/Engineer prior to the commencement of works on site.

9.6.9 Roads, hardstandings, car parks and paths

All materials, workmanship and testing shall be in accordance with the appropriate ASTM Standards and procedures. The Contractor shall submit a document detailing his proposed materials and field testing regime which shall be agreed with the Owner/Engineer prior to commencement of works on site.

All areas of roads or hardstanding that could be subjected to a fuel, oil or chemical spillage shall be constructed in concrete.

9.6.10 Piling

9.6.10.1 General

All materials, workmanship and testing, including concrete manufactured for use in piling, shall be in accordance with the ‘Specification for Piling and Embedded Retaining Walls’ published by the Institution of Civil Engineers (ICE).

If piling is required the Contractor is advised that certain type of piling plant may be unacceptable. Plant which may cause excessive vibration, noise and may lead to settlement and/or damage of adjoining buildings and structures shall not be permitted.

The Contractor shall devise a static pile test programme for the approval of the Owner/Engineer.

9.6.10.2 Design

The Contractor shall be responsible for all matters relating to the design, construction, setting out, installation and testing of piles in conformance with the ICE Specification stated above.

A 40 year pile design life shall be assumed.

All piles shall be designed with a minimum factor of safety of 2.5 applied to the ultimate pile resistance in deriving allowable pile loads. This shall apply to vertical tension and compression loads and to horizontal loads.

Construction drawings, structural and geotechnical designs for all piles shall be submitted to the Owner/Engineer in duplicate for approval at least eight weeks before piling commences on Site.

- 9.53 -


Group effects and drawn down loads shall be allowed for in pile designs and authoritative references shall be used throughout the design process.

The design of piles may be based on appropriate driving formulae but minimum foundation requirements must be as calculated by soil mechanics methods using soil strength and compressibility parameters.

9.6.10.3 Pile acceptance criteria

Permissible pile settlements at proof load shall not exceed settlement criteria imposed by plant manufacturers or shall conform with the following, whichever is the most stringent:

Gas turbine

) )

8 mm total settlement, and 5 mm differential settlement

Other building/plant foundations )

) 15 mm total settlement, and 10 mm differential settlement

9.6.10.4 Pile testing

All pile testing shall be carried out in accordance with the above referenced “Specification for Piling”.

Preliminary test piles shall be required before installation of the working piles unless otherwise instructed by the Owner/Engineer. The location of the preliminary piles and anchorages shall be agreed with the Owner/Engineer prior to installation. On completion of the preliminary tests, piles shall be cut down a minimum of 2 m below ground level and backfilled with approved granular material.

An extended proof load test shall be carried out on two preliminary compression piles and on two preliminary tension piles unless otherwise agreed and instructed by the Owner/Engineer.

The Contractor shall also prove his pile designs by loading tests on selected working piles in respect of the settlement criteria specified above, under 1.5 times the design vertical load using the ‘Maintained Load’ test. Piles to be tested shall be nominated by the Owner/Engineer and a minimum of six proof load tests shall be allowed for.

Integrity tests shall be carried out on all piles installed on Site, using an approved testing system.

9.6.11 Structural steelwork

9.6.11.1 General

Materials shall be in accordance with AISC – Manual of Steel Construction – Allowable Stress Design – 9th edition. Workmanship and testing shall be in accordance with the National Structural Steelwork Specification for Building Construction published by The British Constructional

- 9.54 -


Steelwork Association Ltd unless more stringent requirements apply in the AISC “Manual of Construction” 9th edition.

Steel sections shall be new and of American, British, European or Japanese origin. A mixture of different national sections shall not be allowed. All structural steel sections shall be hot rolled with a minimum grade of A36 in accordance with AISC manual. Auto/manually fabricated welded sections shall only be permitted when a suitable rolled section does not exist i.e. when section required is greater than the largest section size available.

All bolts in elevated steelwork connections shall be minimum grade ASTM A325. All holding down bolts shall be minimum grade ASTM A 307. All bolts shall be supplied to site sheradized and site painted after erection is complete, or alternatively hot dip galvanized bolts may be used.

9.6.11.2 Testing and inspection

The Contractor shall give full access to the Owner/Engineer at all times to the place of fabrication and storage for the purpose of inspection and testing. Mill test certificates shall be provided when requested by the Owner/Engineer.

When so instructed by the Owner/Engineer, the Contractor shall provide samples of the steel to be used in the Works for tests to be carried out at an independent laboratory approved by the Owner/Engineer. The cost of these independent tests shall be paid for by the Contractor.

Should the works or any part thereof fail to pass any test or in the opinion of the Owner/Engineer fail to comply with the Specification, the Contractor shall immediately take such action as is necessary to ensure that the works comply with the Specification.

All defective material and workmanship will be rejected and shall be replaced and reconstructed at the Contractor’s expense.

No splice welding of members between connections shall be permitted without the prior approval of the Owner/Engineer.

The Contractor shall carry out non-destructive testing of all butt welds subject to tensile stresses. Testing shall be carried out in the fabrication shop or on Site as the case may be.

Unless otherwise approved, non-destructive testing shall be by radiographic examination. Alternative forms of testing, if approved, shall comply with the appropriate American Standard (or British Standard if no suitable American Standard exists).

Runway beams shall be tested in accordance with the requirements of BS 2853 and completed test certificates shall be supplied to the Owner/Engineer.

9.6.11.3 Shop drawings

The Contractor shall prepare fully detailed shop drawings with supporting calculations for submission to the Owner/Engineer for comment and approval prior to commencement of any fabrication.

- 9.55 -


Once approved, no changes or modifications shall be made without the Owner/Engineer permission. Approval by the Owner/Engineer shall not relieve the Contractor of his responsibility for the correctness of all measurements, detailing, fabrication, alignment and erection of the work.

9.6.11.4 Protection to steelwork

The preparation, protection and painting systems selected for ferrous surfaces shall provide a life to first maintenance of 20 years. BS EN 12944 – paints and varnishes – corrosion protection of steel structures by protective paint systems and BS EN ISO 1461: hot dip galvanized coatings on fabricated iron and steel articles – specifications and test methods shall be deemed to apply. The Owner/Engineer will select the finish colour.

The Contractor shall prepare and submit, to the Owner/Engineer, four copies of a complete protection and painting schedule covering each and every item to be coated and shall fully describe the systems to be used including surface preparation, type of coating/paint, application methods, number of coats and dry film thickness of each. The Contractor’s schedule, which will also identify the paint manufacturer and include representative colour samples, will be subject to review and acceptance by the Owner/Engineer. The Owner/Engineer will be at liberty to revise the Contractor’s schedule as he deems necessary to provide the degree of protection intended, at no additional cost to the Owner.

It shall be understood that the intent of the specification is to detail a protection against corrosion and other types of damage whilst being aesthetically pleasing. It shall be the Contractor’s responsibility to schedule and execute the painting and coating work to this end.

The following is indicative of the type of corrosion protection required for the various structural elements:

Access stairways, walkways, flooring, ladders, cladding rails and roof purlins, etc.

Hot dip galvanized to BS EN ISO 1461, fixed with spun galvanized or sheradized bolts. All external fixings to be hot dip galvanized. All galvanized internal stairways are to be degreased and finished with similar paint system to the main steelwork after suitable compatible etch primer has be applied.

Main steelwork framing Paint system to BS EN 12944 or hot dip galvanizing to BS EN ISO 1461, to give at least 20 years to first maintenance fixed with spun galvanized or sherardized bolts. Preparation – acid pickling or grit blast all surfaces to SA 2.5 SUS 955900 or both as appropriate.

Where fire protection is required this shall be an intumescent paint system in exposed

situations (subject to required fire rating being achievable), or, where concealed, a fire resistant board system will be acceptable.

All corrosion protection coatings shall be applied in accordance with the manufacturers written instructions. Unless specifically approved otherwise, all coats applied to a surface shall be products of the same manufacturer. Additionally, in so far as possible and practical, paint for the work as a whole shall be products of the same manufacturer.

- 9.56 -


Where any coats are damaged, all loose and damaged paint shall be removed down to the bare steel using a needle gun and/or rotary wire brush and adjacent sound paint which is to be overcoated shall be thoroughly abraded to ensure adhesion of touch-up paint, all to the satisfaction of the Owner/Engineer. Affected areas and adjacent sound paint shall be cleaned, degreased, washed down and dried and protection applied with primer overlapping abraded paint 20 mm and each succeeding coat overlapping by 20 mm.

All galvanized surfaces shall be degreased prior to coating with the approved primer and paint system.

Surfaces which are to receive an intumescent fire protective coating shall be delivered to Site with travel coatings applied and shall be suitably protected until immediately prior to the fire protective coatings or casings being applied. The latter shall be applied as late as possible in the construction programme subject to other trades and operations. Primer and travel coat shall be compatible with the fire protection coating.

9.6.11.5 Fire protection to steelwork

The fire protection to steelwork shall be an approved intumescent paint or board system to give 2 hour fire protection when tested in accordance with BS 476 Part 8.

Spray or paint coatings, where/if applicable shall be applied onto previously primed steelwork. Application to be made in strict accordance with product loading rates for base coat and top sealer specified for required fire resistance in manufacturer’s product application notes. Suitable mesh ‘reinforcement’ shall be incorporated in spray coatings to prevent loss of insulation when subject to mechanical damage. Boarding systems shall also be suitably reinforced at corners to prevent mechanical damage.

The coatings shall be applied by a specialist applicator strictly in accordance with the product manufacturer’s recommendations. The whole of the fire protection proposals and application shall be in accordance with the current Building Regulations and to the satisfaction of the Local Authority and the Fire Authority.

9.6.11.6 Erection

All steelwork shall be effectively stayed as necessary during the carrying out of the Works.

Finished structures shall be plumb, level and true to dimensions, within the tolerances specified in the National Structural Steelwork Specification for Building Construction.

Prior to the erection of permanent steelwork, the Contractor shall submit for the Owners/Engineers approval a detailed method statement with all supporting drawings and calculations setting out his sequence for erection, laydown areas, details of cranage etc. The Owners/Engineers approval shall not relieve the Contractor of his responsibilities under the Contract.

- 9.57 -


9.6.11.7 Despatch, handling and storage

All bolts, nuts, washers, plates etc shall be transported to Site in properly marked and sealed containers, suitably protected to prevent damage during transportation.

The Contractor shall unload and store all fabricated steel at the site. Any structural steel or accessories arriving at Site in a bent or distorted condition shall, when permitted, be properly straightened to the satisfaction of the Owner/Engineer. Any member that, in the opinion of the Owner/Engineer, has been damaged to the extent that its properties and performance in the Works are suspect shall be replaced by a new member at the Contractor’s expense.

Proper care shall be taken in storing and handling fabricated materials at Site to avoid damage to the member and painting. Stacking shall be carried out clear of the ground and in order of erection to reduce multiple handling.

9.6.11.8 Foundation bolts

The Contractor shall provide templates to enable all stanchion bolt assemblies to be cast into the concrete foundations with the correct alignments.

Holding down bolts, assemblies, templates, tubes and washers shall be delivered to the site in sufficient time to position and build them into the foundations. Boxing out for bolts shall not be permitted unless specifically requested by the plant suppliers. In such cases the boxes shall have flared bottom providing mechanical wedging. The projection of threaded portions of bolts above the foundation level shall be adequate to properly secure the nuts.

9.6.12 Surface water drainage and buried pressure pipelines

Materials, workmanship and testing shall be in accordance with the Civil Engineering Specification for the Water Industry 5th edition published by the Water Research Centre or similar American or Iraqi Specification. This document shall be supplemented by the construction and testing recommendations set down in BS EN 752 and BS EN 1610.

The drainage and pipeline systems shall be compatible, in all respects, with the liquids that have to be carried.

9.6.13 Building drainage

All materials, workmanship and testing shall be in accordance with the manufacturer’s recommendations and BS EN 12056 and BS EN 752 or similar American or Iraqi Standards.

The Contractor shall submit to the Owner/Engineer a statement detailing his test procedures and testing schedule.

9.6.14 Brickwork and blockwork

All materials, workmanship and testing shall be in accordance with BS 5628. Bricks for the construction of manholes, inspection chambers, catchpits etc, shall be Class B engineering bricks complying with BS 3921.

- 9.58 -


9.6.15 Builder’s work

All materials and tests shall be in accordance with the relevant British Standards. Workmanship shall be in accordance with BS 8000 ‘Workmanship on Building Sites’. Construction shall be to the tolerance specified in BS 5606 ‘Guide to Accuracy in Buildings’.

9.6.16 Access

Access to and exit from the site shall be determined by the Contractor but shall be subject to agreement with the Owner/Engineer. Height restrictions both on and of the site must be observed at all times.

9.6.17 Fencing

9.6.17.1 General

The Contractor shall inspect the existing boundary of the specified power station and check its condition, and shall submit a report of his findings to the Owner/Engineer who will agree the extent, and type, of replacement/repair works necessary to refurbish the perimeter fence to an acceptable condition, or if agreed the installation of a new fencing.

The Contractor shall also erect a new construction fence, 2.1 m high topped with three strands of barbed wire, around the perimeter of his work area. The location of this new fence shall be agreed with the Owner/Engineer. The aim of the new fence is to secure the Contractors work area for the new OCGT power station. The fence shall be provided with locked gates at agreed road crossing locations. The fencing shall be of the unclimbable, security or anti intruder type consisting of chain link mesh as specified below. It should be of robust design to deter outside intrusion.

A clear opening of at least 8 m, together with an adjacent personnel gate and an electrically operated balancing lifting barrier complete with skirt shall be provided. The gates shall be operable by push button at the gate and in the adjacent gatehouse. The entrance shall be remotely monitored by CCTV at a distance from the gate house with sufficient provision of cameras to view all sides and possibly the interior of any vehicle seeking entry, before allowing reaching the gate house.

The Contractor shall submit his proposals for new fencing works based upon the description of the works above and the requirements below. His submittal shall detail the fence materials proposed and should include, but not be limited to, the following:

a. Posts (materials, spacing, etc)

b. Fencing fabric (inclusive of coatings type and class)

c. Gates (vehicular an personnel access)

d. Barrier.

The entrance gate, posts, barrier and installation shall be robust enough to halt any forced entry from a motor vehicle. If warranted the Contractor shall provide anti-intrusion barrier/ramp so that no vehicle can enter the station site without lowering the anti-intrusion barrier.

- 9.59 -


9.6.17.2 Standards

The following Codes and Standards are to be used in the design and manufacture of fencing:

ASTM A121 Specification for Zinc Coated (Galvanized) Steel Barbed Wire

ASTM A393 Specification for Zinc Coated Steel Chain Link Fence Fabric

ASTM A491 Specification for Aluminium Coated Steel Chain Link Fence Fabric

ASTM A626 Fence Fittings

ASTM A1083 Pipe, Steel, Hot Dipped, Zinc Coated (Galvanized), Welded for Fence Structures

ASTM F668 Specification for Polyvinyl chloride (PVC) Coated Steel Chain Link Fence Fabric

ASTM F900 Industrial and Commercial Swing Gates

9.6.17.3 Excavation and grading

The Contractor shall clear a strip one metre wide of all growth on either side along the line of the fence and shall grade off this strip to remove local irregularities before erection of the fence commences. The Contractor shall excavate to the lines and levels required by the drawings. The base of the excavation shall be consolidated. Suitable material arising from the excavations shall be used for backfilling as needed. Surplus material shall be stored for subsequent use.

9.6.17.4 Concrete

Foundation to posts, struts, bases and anti-burrowing kerbs shall be in concrete of at least 20 N/mm2.

Foundations to posts shall be at least 400 mm in diameter and 1.4 m deep for line posts and 500 mm diameter and 1.6 m deep for terminal posts. Tops of foundations shall be crowned so as to shed water.

Embedded steelwork in concrete shall be galvanized.

9.6.17.5 Chain link fencing, posts, gates and fittings

Fence fabric shall be steel chain link (minimum 3.00 mm nominal diameter and maximum 50 mm mesh size) and either zinc coated to ASTM A 392 (minimum, Class 2) or aluminium coated to ASTM A491 (minimum 107 g/m2). PVC coating shall be to ASTM F668.

Barbed wire shall conform to ASTM A121. Size shall be 12.5 gauge. Minimum weight of coating shall be Class 3.

Top rails shall conform to ASTM F1083.

- 9.60 -


Posts shall be either precast concrete, or steel conforming to ASTM F1083. Fittings shall conform to ASTM F626. Post lengths shall be at least 1m longer than the fabric height.

Galvanized steel or aluminium arms shall accommodate three strands of barbed wire at 45 degrees outside of the fence line. Top strand of barbed wire shall be 300 mm above the fence fabric.

Gates shall be fabricated from steel of compatible shape to the fences. Gates shall conform to ASTM F900. Frames shall be connected at joints by specially designed joints to form an inflexible panel. Galvanized steel braces shall be installed where necessary to provide inflexibility. Gates shall be provided with pre-galvanized malleable iron hinges, latches and latch catch. Latches shall be able to accommodate a padlock fastened from either side. Hinges shall allow 180 degree swing. Double gates shall have a centre rest, iron bolt and hold open chains. Fabric shall be as specified for fencing.

Double gates shall be sized to suit the road widths or entrances for which the gates are being provided. Single personnel gates shall be the same height as the fence and shall be a 1 m wide minimum.

The fencing standard may be upgraded as per contract requirements to suit the location of the site and the above standard is only the minimum requirements.

9.6.17.6 Erection

Set all posts plumb and the fence line straight between corner posts and space posts uniformly. Maximum spacing between posts shall be 3 m. Straining posts shall be provided at all ends and corners of the fence, at changes in direction of acute variations in level and in straight lengths of fencing at intervals not exceeding 60 m. All posts shall be founded in concrete bases. The top of the base concrete shall be 50 mm above ground level.

Anti-burrowing kerbs shall be bedded on in situ concrete with the top 50 mm above ground level.

There shall be four rows of evenly spaced line wire. The top wire shall be doubled, making five line wires in all. The bottom wire shall not be more than 25 mm above the kerb. There shall be three rows of barbed wire at the top.

The bottom 50 mm of the chain link shall be embedded into the concrete kerb.

9.6.18 Landscaping

The layout of landscaped areas shall be agreed with the Owner/Engineer prior to commencement of work, including the selection of trees, plants, ground cover etc.

In areas where the new works adjoin existing hard and soft landscaping, good quality landscaping shall be provided to match in with the existing environment.

- 9.61 -


9.6.19 Laydown area

Laydown areas shall be established by the Contractor and shall be subject to approval by the Owner/Engineer. The Contractor shall allow for any necessary traffic management measures which are required to satisfy the local authority and highway regulations. On completion of the works, laydown areas shall be cleared of all debris, graded and laid to level and left in a tidy condition to the approval of the Owner/Engineer.

9.7 Electrical building services

9.7.1 Scope of works

The scope of works for the Electrical Building services shall include the following:

a. lighting systems

b. small power systems

c. distribution system

d. cables and Wiring

e. lightning protection system.

The Contractor shall be responsible for the complete design, detailed design calculations, equipment selection, installation, testing and commissioning and testing of the complete electrical building services systems subject to the approval of the Owner/Engineer.

Design calculations, system diagrams and construction drawings shall be submitted for approval. Design information shall be submitted with description of the system and all calculations as detailed in Section 9.8.2

The Contractor shall ensure that the equipment is provided suitable for the location it is to be installed in taking into account temperature and environmental conditions expected on site.

The Contractor shall include for providing all as constructed drawings, which shall be prepared as the works proceed. Completed sets of Operational and Maintenance Instructions including all test, commissioning and any other documentation required to maintain the works shall be submitted the Owner/Engineer for approval.

9.7.2 Lighting systems

9.7.2.1 Scope of works

Lighting systems shall be provided throughout the station for all areas, outbuildings and external areas to the levels required by this Specification.

The lighting system provided shall be in compliance with the Regulations, Codes and Standards and comprise normal, emergency (including operational security lighting) and external lighting systems that will include a fence security lighting system.

- 9.62 -


The mounting positions of all luminaries in all areas shall be arranged to allow maintenance to be carried out on each fitting with a minimum of labour and access equipment.

The design and installation of lighting and shall be based on the following Regulations/Standards:

a. Requirements for Electrical Installations, IEE wiring regulations BS 7671 as issued by the Institution of Electrical Engineers, London and British Standards, UK.

b. The Code for Lighting, Lighting Guides, as issued by the Chartered Institution of Building Services Engineers (CIBSE) London, UK.

All interior and exterior lighting designs shall be undertaken using computerized calculation and shall be presented using the point-by-point calculation method or flux distribution from luminaries reaching a grid of illuminance points spread across the working plane for all of the indoor and outdoor lighting.

Lighting design shall take into account efficiency, symmetry, application, operational plant, glare, glare that might affect the CCTV cameras, computer screen environments, maintainability and long life. The CIBSE definitions and recommendations for uniformity ratio, diversity, maintenance factor shall be applied. The Contractor shall state the assumptions applied for cleaning and re-lamping of luminaries and ensure that these are compatible with the normal practice being applied to the local environment. The Contractor shall design using the most economical method of achieving the maintained illuminance taking into account electricity costs and lamp replacement costs etc.

Lighting levels shall be graduated as required for comfort, safety and monitoring.

The lighting systems will consist of the following systems.

Normal lighting system 400/230 V ac serving approximately 75 per cent of the total lighting at a given area via the lighting distribution system.

The emergency lighting system 400/230V ac serving 25 per cent of the total load at a given area and connected via a lighting distribution board. Basic source of power shall be the diesel generator. The emergency lighting system shall also be capable of illuminating all exit signs, doors, stairways, corridors, other routes of exit and outside each fire exit together with other areas of specific risk. The emergency lighting system shall enable persons to make their way safely out of the area or premises without assistance.

Operational (high risk task area) lighting system 230 V ac connected via distribution boards for control rooms and walkways. Basic source of power shall be from an independent inverter system. For buildings remote from the inverter the exit signs and buildings shall be illuminated by self contained battery packs. This system shall be capable of 3-hour operation

Circuit design shall ensure that operation of a circuit protective device or failure of a circuit component shall result only in limited loss of illumination in a room or area.

- 9.63 -


9.7.2.2 Normal lighting

The lighting installation, shall under normal operating conditions and throughout the stations operational life be capable of providing the minimum service levels of illumination as listed below: These levels shall be based on measurements being taken after the lamps have operated for not less than 100 hours. The method of measurement is to be carried out in accordance with the International Commission of Illumination (CIE) Publication No 29. Measurements to be generally taken at floor level.

Areas typically

Description of activity

Standard maintained illuminance (lux)

Gas turbine area Operating floor 200

Substations Control areas/room 250-500

Black start/emergency Data printers 300

Diesel generator building Engineers/offices 300

Control and administration building Monitoring room 300

Chiller building Telecoms room 300

Workshop and stores Mess room 200

Water treat plant Metering room 200

Fire fighting pump house Switch room 200

Toilets 150

Access corridors 150

HV equipment floors 150

Marshalling room/stairwells 150

Cable floor/cable risers 50

Battery room 150

Entrance 150

Fuel oil plant room 150

Stairwells/corridors 150

Station unit switch room 200

Workshop/store 300

C&I equipment 300

Electronics room 300

Switchgear room 200

prayer room 250

Stores 200-300

Chemical laboratory 300

Kitchens 500

Conference rooms 300-500

Locker rooms 200

Cable tunnels 50

Transformer compounds 30

- 9.64 -


If there are areas that are not included in the above BS ISO 8995 should be used for guidance.

The lighting shall be designed to provide visual performance, safety and amenity. Visual performance shall be free of excessive stroboscopic effects and flicker from discharge type lighting.

The Contractor shall take into account the expected wall, floor and ceiling reflectance values when undertaking the design calculations. The lighting designs shall also take into account the proposed equipment locations.

The Contractor shall base his design calculations on fluorescent lamps of a white colour and a colour-rendering index of typically 95. Lamps shall be triphosphour or multi-phosphour type. High frequency ballasts shall be provided in all fluorescent luminaires.

The use of low energy/compact fluorescents will be considered wherever the location and purpose of the area is suitable. The design will incorporate energy saving systems and make possible use of local isolation, movement and presence detectors wherever such a system will provide potential energy savings.

The selected luminaire shall be suitable for its application.

All normal lighting shall have uniformity levels (ratio of average to minimum) no less than 0.8. The type and quantity of fixtures and their luminous intensity shall relate to the space being illuminated and shall take into account the effect of the architectural space concept and colour scheme. Local task lighting shall be provided as required to keep open area lighting to the minimum requirement.

The selection of luminaries and requirements of illumination for various areas shall be in accordance with the recommendations published by the Illuminating Engineering Society with consideration of the safety and working conditions on the Project. The Contractors design shall reduce to a minimum the different types and sizes of luminaries used on the project and shall use wherever possible linear fluorescent luminaries surface mounted in plant locations. The use of one standard length fluorescent tube is preferred but this does not exclude using other lengths if required for design considerations.

Luminaires shall be located as far as is reasonably practicable to allow maintenance to be carried out on each luminaire with a minimum of labour and access equipment

9.7.2.3 Emergency lighting

All emergency lighting schemes shall be arranged to provide the required illumination on interruption or failure of normal lighting supply, operation of a circuit breaker or fuse or manual acts such as accidental opening of a switch controlling normal lighting facilities. The Contractor shall design, supply, install, wire and connect up a complete emergency lighting installation with a minimum of 3-hour operation, which shall be carried out in accordance with the following:

- 9.65 -


a. BS 5266, Part 1, 1999 (Code of Practice for Emergency Lighting at Premises)

b. BS EN 1838, Lighting Application – Emergency Lighting.

This shall include the provision of a 230 V ac UPS system for the operational (high risk task area) lighting system areas. The Contractor shall design for dedicated UPS units that are to be for emergency lighting use only.

Emergency lighting including operational (high risk task area) lighting system shall be supplied to all areas.

The emergency lighting system shall consist of the following types of fittings:

a. non-maintained 230 V ac

b. maintained 230 V ac.

Emergency lighting (operational (high risk task area) lighting system) fed by the dedicated UPS system

- Fluorescent luminaires, operational areas

15 lux at floor level Non-maintained

- Fluorescent luminaires or high bay metal halide discharge luminaires with auxiliary lamp for instant illumination inside the electrical operational rooms.


- Fluorescent luminaires inside switchboard/electronics rooms to serve as standby lighting

100 lux at floor level Maintained

- Illuminated exit signs of all final exit doors (non UPS supply)

Maintained, self-contained bulkheads

- High bay metal halide discharge luminaires with auxiliary lamp for instant illumination

15 lux at operating floor level) Non-maintained

- Floodlight type units mounted on the turbine/generator house side walls area.


Emergency lighting on paths of egress at floor level shall have a maximum-to-minimum illumination uniformity ratio of 40 to 1, which shall not be exceeded. The emergency lighting for stairs and escalators shall emphasise illumination on the top and bottom landings and at all intermediate landings

The emergency lighting shall be arranged to come into operation automatically upon failure of the normal lighting sub-circuit failure. The UPS shall be sized to take 110 per cent of the full design load for three hours.

- 9.66 -


9.7.2.4 External lighting

The Contractor shall design supply, install wire and connect up a complete external lighting system for all areas of the development.

The detailed positioning of all lighting points to achieve the illumination levels shall be subject to the approval of the Engineer and must be in uniform and symmetrical arrangement.

All lighting shall be designed to meet the requirements of lighting guide LG06: 1992. For the outdoor environment issued by the Chartered Institution of Building Services Engineers. Illumination levels shall also be in accordance with the lux levels indicated below. Where these two contradict the more onerous shall take precedence. Where a range of average illuminances are recommended in the guide for a particular application, the Contractor shall design his lighting scheme to provide an illuminance not less than midway between the recommended upper and lower valves.

Transformer area 100 lux Fluorescent

Operating plant areas:

Machinery areas 200 lux Metal Halide

Platforms/ladders (active) 50 lux HP Sodium

Walkways 50 lux HP SODIUM

Road, platform/ladders (inactive), 30 lux HP Sodium

The security fence shall be continuously illuminated during hours of darkness by linear low-pressure sodium lighting to provide an even vertical illuminance of 25 lux on the face of the fence. These low mounted glare lights will allow the security patrol personnel to view the surveyed field, the area outside the fence is so that persons outside of the fence can not view a guard inside the project site boundary. This shall be undertaken utilizing luminaires installed on 3 m high hot dipped galvanized columns

When lighting columns are required, these shall be complete with luminaries’ mounted at suitable heights in accordance with design calculations and at suitable mounting locations.

All external doors of buildings shall have external luminaires installed adjacent to the doors to provide illumination immediately outside entrances. This is in addition to any other external or roadway lighting.

9.7.2.5 Related Standards

a. IEC 60364 Electrical Installations of Buildings

b. IEC 60064 Specification for tungsten filament lamps for general service (BS 161) (batch testing).

c. BS 5649 Steel columns for street lighting

- 9.67 -


d. BS EN 60598 Luminaires (BS 4533) Pt 1 General requirements and tests

Pt 2 Detail requirements

e. BSEN 60081 Tubular fluorescent lamps for general lighting service. (BS 1853)

f. BSEN 60921 Specification for ballast for tubular fluorescent lamps. (BS 2818)

g. IEC 60188 High-pressure mercury vapour lamps

h. BSEN 62035 (excluding Fluorescent Lamps) (BS 3677)

i. IEC 60662 High-pressure sodium lamps (BS 6193)

j. BS 3871 Miniature and moulded case circuit-breakers

k. BS 4782 Ballasts for discharge lamps (excluding ballasts for tubular fluorescent lamps)

l. IEC 60947 Low-voltage switchgear and control gear

m. Codes for Interior and exterior lighting (Chartered Institute of Building Services Engineers.)

9.7.2.6 Materials

Luminaires

A list of proposed luminaires is shown below. However, this list shall not be regarded as complete until the design stage is finalized. The luminaire specification shall be produced ensuring that the equipment ordered is of the latest design, quality and shall be suitable for its final location.

Luminaires used indoors shall be minimum IP 21 protection and for external use IP 65

The types of luminaires shall be as follows:

a. Recessed fluorescent luminaires with prismatic diffuser,

b. Single lamp, circular luminaire with opal diffuser,

c. Surface mounted fluorescent luminaires

d. Floodlight with mounting bracket,

e. Indoors area, high bay ceiling or pendant mounted light luminaire,

- 9.68 -


f. Weatherproof bulkhead fitting for SON lamp,

g. High bay metal halide discharge luminaire with c/w auxiliary lamp for instant illumination (200 lux).

h. Non-maintained 230 V ac twin floodlight type luminaires (15 lux).

i. Non-maintained bulkheads (15 lux).

j. Maintained, self-contained bulkheads (for EXIT illuminated signs). The final exit signs shall not be fed by the UPS system but from the normal lighting with un-switched conductors.

9.7.2.7 Switches

Switch types shall include single or multi-pole, one way, two-way and intermediate with or without pilot lamps, as may be required for each application.

All areas shall be individually switched with two way and intermediate switching provided where necessary if there is more than one method of access and for walkways and stairways. Luminaires installed on different floor levels or at different task locations to be controlled by their own switches. Light switches for indoor use shall be the quiet rocker-dolly type of thermoplastic material flash or surface mounting, with the degree of protection suitable to the environmental conditions of the specific area of the substation.

Where required by the design push buttons shall be provided for the control of large open area lighting installations. Push buttons shall be positive action, spring loaded having a ‘stay put' contact action with push to close and push to open action. Push buttons shall be 5 A rated at and shall have chromium plated steel cover plates.

All cover plates for lighting control switches shall be chromium-plated steel.

9.7.2.8 Lighting contactors

Contactors controlling outgoing circuits shall be located within the local distribution board and shall be rated for ‘continuous load' condition. Contactors located within the boards do not require a separate enclosure but the construction of the contactor shall be such that it is not possible to come into contact with any live parts. The operating coil shall be suitable for operation at 230 volts 50 Hz single phase.

9.7.2.9 Workmanship

The mounting height of luminaires shall not be lower than 2.4 m unless restricted by the available mounting height or if otherwise approved.

The Contractor shall include all the brackets, supports and fixings, which may be required. Where provided, supports and brackets shall be hot dip galvanized and given an additional coat of epoxy paint.

- 9.69 -


All fluorescent fittings are required to strike successfully at 85 per cent nominal volts and not to extinguish at 70 per cent nominal volts.

All discharge lamps shall have an operating power factor of not less than 0.85.

9.7.2.10 Lamps and tubes

Lamps and tubes installed in the luminaires shall be of approved manufacture and of the correct type, voltage and rating specified in accordance with the related standard.

Fluorescent lamps shall be cool daylight with a minimum life of 7500 hours.

High-pressure sodium discharge lamps shall be colour corrected deluxe white with a minimum lamp life of 24 000 hours operation with the required ballasts.

9.7.2.11 Lighting and control switches

Local switches shall generally control the lighting. Separate switches shall also be provided for local lighting for panels etc and comply with the related Standard. In the central control room the fluorescent lighting shall be provided with "dimming" control to give a graded reduction in lighting levels

In large, areas, such as the turbine house, luminaries for access and inspection lighting shall be switched by contactors controlled by a switch adjacent to the plant covered by a specific load centre.

The design of general and local lighting control shall comply with the following requirements:

a. Not more than ten lighting points to be connected to and final sub-circuit.

b. Two way switches with intermediate where necessary, to be provided for lighting in areas with more than one access, walkways and stairways.

c. Luminaires installed on different floor levels or at different task locations to be controlled by local switches.

Emergency lighting shall be automatically energized on failure of the electrical supply to normal lighting in the relevant area.

Lighting switches shall be selected in accordance with the ON/OFF control requirements of the lighting load and rated for 230 V ac single-phase operations with minimum capacity of 2500 W.

All switches shall be mounted at 1.5 metres above finished floor or platform levels. The switches shall be positioned such that they can be easily located and accessed for use.

The external lighting installation shall be contactor controlled using photoelectric cells.

- 9.70 -


9.7.3 Small power installation


The station and any ancillary areas shall be provided equipped with socket outlets, connection units and isolators to suit the purpose of each building or area. These outlets will be suitable for providing power supplies to all portable equipment, hand tools, portable lamps and fixed equipment required for operating and maintaining the systems

For office areas, equipment and control rooms, maintenance and testing areas or similar, the socket outlet layout shall be designed so as to effectively cover work areas with a 3 metre flexible cable. Socket layout design for all other areas shall give effective cover with a 15 metre portable extension. 110 V socket outlets shall be provided in plant areas to supply power for hand tools etc used for maintenance. The Contractor shall design supply and install a complete small power installation which shall comprise of 230 V/13 A socket outlets, 400 V/200 A oil filtration sockets, 400 V/63 A welding sockets, industrial outlets for plant areas 230 V/15 A (BS EN 60309) and 13 A fused connection units and isolators for various items of fixed appliances.

The 230 V sockets shall be wired as ring main circuits whilst 400 V sockets shall be wired as ring/radial circuits the 230 V switched 13 A socket outlets shall be flush mounted in offices and office type areas.

9.7.3.2 110 V power sockets

A 110 V switched socket outlet system shall be provided in plant areas to supply power for hand tools etc used for maintenance and shall give effective cover with a 15 metre portable extension. The plugs and outlets when in use shall be IP 44 splash proof complying with IEC 60309 and BSEN 60309

9.7.3.3 230V power sockets

A 13 A 230 V socket outlet system (2 pole plus earth) will be provided for offices areas, main plant areas, store areas, equipment and control rooms. This installation will be of the surface/concealed type and will be designed to provide to effective cover to all work areas with a 3 metre flexible cable. The Contract shall provide sufficient sockets for general purposes in all operational areas.

Single-phase socket outlets – 15 A. Single phase 230 V, 15 A socket outlets, connected to the normal power supply shall be of the two gang, 3-pin type in accordance with BS EN 60309. Socket outlet installations for plant room areas shall be surface mounted and shall be located to provide effective cover with a 15 metre portable extension lead. Socket outlets rated at 15 A, 230 V single phase shall be provided for all fixed items of equipment such as small local water heaters and extractor fans etc.

A RCBO rated to trip at 30 mA at the local distribution board shall protect each small powers ring main or radial circuits.

- 9.71 -


9.7.3.4 230V power accessories

Cooker control units shall be provided for kitchen cooking stoves consisting of a 45 amp, double pole main switch with pilot lamp and a connector unit complete with terminal blocks, cable clamps and cover plate.

Water heater switches shall be rated 15 amp, 20 amp or 45 amp depending on load requirements with red pilot lamp and switch plate engraved ‘Water Heater'.

Hand dryer switches shall be rated 15 amp with red pilot lamp and switch plate engraved ‘Hand Dryer'.

9.7.3.5 400 V socket outlets

Power socket outlets shall be rated at either 16 A, 32 A, 63 A or 200 A and shall have 4 pole connections and two earth connections.

The Contractor shall provide socket outlets in all oil filled transformers compounds for the connection of a mobile oil purification plant. The socket outlets shall be located so that the mobile oil purification plant can be positioned in front of each transformer bay using a maximum cable length of 20 metres.

The Contractor shall supply and install welding socket outlets complete with plugs at strategic points located on a nominal 50 metre grid so that all parts of the Plant can be reached using a maximum cable length of 35 metres. The socket outlets shall be 400 V, 63 A, three phase, neutral and earth to BS EN 60309. They shall incorporate an on-load disconnector, mcb rated to suit the switch and a residual current circuit device (RCBO) rated at 30 mA.


a. IEC 60364-5-54 Earthing arrangements and protective conductors for indoor installations up to 1000 V ac and 1500 V dc

b. BS 1363 13 A plugs, socket outlets, adapters and connection units switched and un-switched 13A socket outlets and boxes

c. BS 4343/IEC 309 Specification for industrial plugs socket outlets and couplers for ac and dc supplies.

d. BSEN 60309 Plug and socket outlets

e. IEC 60309 Plugs, socket-outlets and couplers for industrial purposes

f. BS 3871 Miniature and moulded case circuit-breakers.

9.7.3.7 Material

Socket outlets shall be metalclad to IP67, watertight and incorporate a spring-return flap cover. The plug and socket shall be interlocked such that the unit cannot be switched on until the matching plug is fully inserted, nor can the plug be withdrawn with the switch closed.

- 9.72 -


9.7.3.8 Workmanship

The mounting height of general-purpose socket outlets and power socket outlets shall be as follows:

General-purpose socket outlets mounted in walls of rooms such as offices and control room areas shall be 300 mm above finished floor. In all other maintenance type areas, equipment or station areas the mounting height shall be 600 mm above finished floor.

Power socket outlets shall be mounted 1.2 metres above finished floor.

The Owner/Engineer at site shall approve the position of all socket outlets before installation work is commenced

9.7.4 Distribution system


Sub distribution boards shall be provided for the lighting and small power supplies throughout the station. A unique code number shall designate to them and all drawings and diagrams.

The boards shall be 400/230 V ac 3 phase and neutral, generally grouped together where suitable, within a free standing floor mounted totally enclosed cellular cubicle type switchboard or as individual boards where required. Each board shall be equipped with main incomer and sub-main circuit breakers.

The design shall ensure that all equipment is provided that will take the expected symmetrical fault rating and shall be capable of breaking rated load current.

Lighting and small power final sub-circuits shall be supplied from ways protected by miniature circuit breakers. A minimum of 20 per cent of each type and rating of MCB/RCCD ways shall be provided as spares.


a. BS 5486 Pt 12 and 13 Miniature Circuit Breaker Boards.

b. IEC 60947 Distribution boards and all components.

c. BS 5419 and BS 3871 Air break switches, disconnector and MCCB's.

9.7.4.3 Material

Sub-main circuit breakers shall be of the moulded case plug-in and bolted type selected in accordance with the load served and to withstand the actual fault levels at the bus bars. Miniature circuit breakers of the residual current earth leakage type shall be used for socket outlet feeds and some small power supplies.

- 9.73 -


Sub-distribution boards combining lighting circuits and socket outlet circuits shall be electrically separated by the provision of separate bus bars and the socket outlet section shall be protected by RCBO.

The emergency lighting shall be operated (ie switched on due to ac failure) when the voltage of any one phase drops to 80 per cent of normal supply voltage.

The relay shall be able to detect when the 400 V ac supply voltage has fallen to 80 per cent for half a cycle and to energize the emergency lighting within 0.5 seconds. Upon restoration of normal ac supplies a suitable delay shall occur before the emergency lighting are switched off. A timer linked to the low voltage relay shall provide this function but shall not be included where fluorescent tubes are used for the ac lighting. The low voltage relay shall be equipped with a manual override to provide a lamp test facility for the emergency lighting or switch it on manually should the automatic system fail.

The 400/110 V ac power socket boards shall be fed from 4 kVA transformers for each group of 110 V ac socket outlets.

9.7.4.4 Workmanship

Distribution boards shall have an enclosure of zinc coated or galvanized steel of minimum thickness of 1.8 mm, having a hinged door with padlocking.

Enclosures shall have a degree of protection to IP 20 for office type rooms (indoor locations) IP 44 for indoor locations in plant areas and IP 65 for outdoors and damp situations.

Access doors shall open 120° without obstruction to give access for operation of switches for MCB and RCD’s. The local distribution boards shall be generally mounted at 1450 mm above ground level with a clear working space of 1000mmfor operation testing and maintenance.

Gland plates shall be fitted to both top and bottom for cable entries to incoming and outgoing circuits and allow for spare capacity

9.7.5 Cables and wiring


The supply and erection of all LV power cables; control cables and wiring, complete with accessories shall be provided.

Cable racks shall be installed within the power station for the incoming and outgoing feeder cables at sub-distribution boards. The cableways shall be designed to provide the best cable protection and minimize the risk of fire or damage in the event of fire. All cable routes and trays shall be numbered and registered on the relevant drawings.

The types of cables that can be used are in Section 7.16 Cabling.

Segregation of ac and dc cables should be in accordance with the related Codes and Standards.

- 9.74 -


The minimum cross section of cables to supply luminaires is 2.5 mm2 and for power

outlets circuits shall be 4.0 mm2 cables.

Cables shall be laid on galvanized metal trays or run in galvanized steel conduits.

9.7.5.2 Workmanship

Lighting suspension trunking shall be manufactured from heavy gauge sheet steel with a galvanized finish complying with the related Standard. Trunking shall be complete with all manufactured standard couplings, bends, tees, cable retainers, stirrup suspension, hangers and fixing brackets and all other accessories as required.

Self-tapping screws shall not be used in the trunking assembly and the inner surface of the trunking shall have a smooth finish.

All conduits terminating at the trunking shall be bonded together and to the trunking. The trunking shall not form part of the earth continuity conductor and separate earth conductor shall be provided in the trunking. Copper earth bonding links shall be fitted across all joints.

Lighting trunking shall be used exclusively for the purpose of lighting fitting suspension and the routing of directly related wiring.

9.7.5.3 Conduit

The conduits shall be continuous from outlet to outlet to distribution boards, junction or pull boxes and secured to all boxes so that each system is electrically continuous from service to outlet.

9.7.6 Lightning protection system


The Contractor shall provide and install a lightning protection system to provide the necessary protection to each building. Each building shall have its own air terminal network, down coming tapes and earth points.

The complete installation shall comply with the requirements of BS BS 6651 and components BS EN 50164

The Contractor shall connect together with a perimeter conductor all earth rods of each individual lightning system. From the nearest point of the perimeter conductor the Contractor shall provide a link to the power station earthing system as detailed in Section 7.15.

9.7.6.2 Workmanship

Joints between lightning protection conductors shall be accessible without disturbing the roof structure, no joints located below roof finish will be accepted.

- 9.75 -


At ground level the down conductor terminates shall terminate at a brass test clamp mounted at 1500 mm above finished floor level.

The earth electrode shall comprise as a minimum 4 No 1200 mm, 15 mm diameter, hard drawn solid copper ground rods, screw coupled. See Section 7.15 for ground testing requirements. Final connection to the electrode rod shall be by a pressure type clamp connection.

The complete installation shall be tested in accordance with the relevant Standards. The Contractor shall provide the Owner/Engineer with copies of the test certificate produced for the lightning protection system.

Surge arrestors to be fitted for protection against transient surge’s that occur during lightning strikes

9.7.6.3 Bonding

The Contractor shall include for bonding all items of exposed extraneous metalwork, ie masts, AHUs etc and louvres, to the lightning protection system.

A separate electronic earthing system shall be installed as per the latest Codes and Standards for all electronic and communication systems. This system shall be separate from the plant protective bonding system.

The Building Services systems shall all be bonded to the nearest earthing point distribution bar normally located within the electrical equipment rooms. The earthing arrangement and protective conductor system shall be in accordance with the BS 7671 Requirements for Electrical Installations

9.8 Mechanical Building Services

9.8.1 Scope of Works

The scope of work for the Mechanical Building Services shall include the following:

For piped services, the Service Water and Compressed Air Installations shall be extended into each building as required to provide wash down/maintenance facilities. The Contractor shall comply with the requirements of the Mechanical Specification in the provision of these services. Interface locations shall be agreed with the Plant Contractor, typically 1 metre from the building external wall.

The site potable water distribution system shall be extended into each building as required for domestic hot and cold water supplies. Interface locations shall be agreed with the Plant Contractor, typically at an external stop valve 1 metre from the building external wall. The domestic hot and cold water services shall comply with the requirements of BS 6700:1997 – “Design, installation, testing and maintenance of services supplying water for domestic use within buildings and their curtilages” - and with local Iraqi Codes. Plant areas and emergency washing/shower facilities are also to be supplied with potable water.

- 9.76 -


The heating, ventilation and air-conditioning (HVAC) systems shall be installed to provide the required inside conditions as indicated in the Specification below. Design, installation, testing and commissioning of systems shall comply with the latest applicable Codes and Standards, eg ASHRAE, NFPA, SMACNA, ARI.

The Contractor shall be responsible for the complete design, detailed calculations, equipment selection, construction, controls, testing and commissioning of the whole of the Mechanical Building Services, subject to the approval of the Owner/Engineer.

The above systems shall comply with the relevant sections of the Specifications. These shall include, but not be limited to, the following:

a. Potable water

b. Service water

c. Service (compressed) air

d. General mechanical plant

e. Thermal insulation

f. Fire detection

g. Fire suppression

h. Testing and commissioning

i. Handover, O&M manuals, record drawings.

9.8.2 Design information

Design calculations, system diagrams and construction drawings for all services and systems shall be submitted to the Owner/Engineer for approval, before procurement/construction is commenced. Design information shall be submitted with descriptions and calculations under the following headings.

a. Objective

b. Concept of system

c. Method of calculation

d. Design criteria

e. Calculations

f. Appendices.

Where computer produces calculations, the Contractor shall provide details of the hardware and software used. All computer programs shall be ASHRAE approved, industry Standard.

- 9.77 -


Reference Codes and Standards shall be noted in each section of the calculation where appropriate. The Contractor shall provide any further additional information called for by the Owner/Engineer in substantiation and for approval of his design.

9.8.3 Quality control

All equipment for the Mechanical Building Services shall be obtained from member firms of the relevant Trade Association(s).

The Contractor shall submit full details for approval, including samples where necessary, of the following components which he proposes to use.

a. Refrigeration plant and accessories

b. Air handling units

c. Fans (all types)

d. Air filters

e. Grilles and diffusers

f. Fire/Smoke dampers

g. Air cooling coils

h. Air heating coils

i. Control systems and BMS

j. Water storage tanks

k. Pipes and fittings for all systems.

All works shall be carried out by skilled operatives, fully conversant with the standards of workmanship required.

9.8.4 Domestic hot and cold water services

The domestic hot and cold water services within the buildings shall comply with the requirements of BS6700:1997 – “Design, installation, testing and maintenance of services supplying water for domestic use within buildings and their curtilages” – and /or in accordance with local Iraqi codes.

All buildings or areas shall be provided with a cold water storage tank of sufficient capacity to meet one day’s consumption for the building or area served. The tanks shall be of GRP insulated construction, locally manufactured, and where possible located within the building envelope to reduce heating in summer.

- 9.78 -


The hot water systems shall be served from local electrical water heaters, with central storage systems being provided only for large buildings with heavy demand for hot water.

In addition to domestic/sanitary water services, the Contractor shall include for potable water supplies to emergency wash-down and shower facilities in battery rooms and chemical areas, to HVAC humidifiers and to central/emergency water chilling systems.

The Contractor shall include for all necessary inspection, testing and commissioning, including disinfection, of the complete hot and cold water services installations.

9.8.5 HVAC systems

9.8.5.1 Design/systems requirements

The HVAC systems shall be designed, installed and commissioned in accordance with the latest applicable codes of the following:

a. ASHRAE. American Society of Heating, Refrigerating and Air Conditioning Engineers.

b. SMACNA. Sheet Metal and Air Conditioning Contractors National Association.

c. NFPA. National Fire Protection Association.

d. ARI. American Refrigeration Institute.

e. ANSI. American National Standards Institute.

f. AABC. Associated Air Balance Council.

All systems shall be designed and installed to provide acceptable environmental conditions for each area as specified below. The conditions of temperature, humidity, air movement and air filtration shall be controlled as required in the respective areas in summer and winter.

HVAC systems serving critical areas such as Control Rooms shall be provided with duty/standby air handling and mechanical cooling plant to ensure continuity of operation.

HVAC systems shall be arranged to shut down in the event of a fire alarm, seal supply and extract ducts as required for the application of clean agent fire suppression systems, and start up smoke control pressurization systems. Provision shall be made in all plant areas for the venting and clearance of smoke and fumes in the event of fire, by means of roof vents or extract fans.

All systems and components shall be suitable for the design life of the plant, and be designed for minimum life cycle cost and complexity, consistent with functionality, ease of maintenance and reliability

- 9.79 -


9.8.5.2 Ambient design conditions

For all general cases the HVAC systems the ambient design conditions shall be as follows.

[Summer 48°C d.b. 30°C w.b.]

[Winter 4.4°C d.b 1.7°C w.b]

[Site Altitude metres]

The HVAC conditions described here cover the majority of sites in Iraq but extreme temperature ranges, as stated in other parts of the Specification, are possible in small number of cases. Contractor shall, based on the general requirements described below, implement small adjustments to suit the local extreme condition which could be high temperature, low temperature or high altitude.

9.8.5.3 Internal design conditions

The HVAC systems shall be designed to obtain the internal conditions and system redundancy as indicated in the following table.

Area (s) Internal Condition Comment

Control rooms

Offices

Electronic rooms

Laboratories

Relay rooms

Summer:

26ºC db ± 1.5ºC

50% r.h ± 5%

Winter:

22ºC ± 1.5ºC

40% r.h minimum.

Central air conditioning systems with 2 x 100% air handling units and standby mechanical cooling.

Workshop/stores

Lecture rooms

Corridors.

Prayer rooms.

Summer:-

26ºC db ± 1.5ºC

50% r.h ± 5%

Winter:

22ºC db ± 1.5ºC

No humidity control.

Central air conditioning systems 2 x 50% air handling units. No standby mechanical cooling.

Corridors.

Stairs.

28C db max.

20C db min.

Pressurization systems for smoke control may be required in these areas.

Toilets 28C db max.

10C db min.

Extract ventilation (10 AC/h min.)

Rooms under negative pressure.

Mess rooms. 28C max.

15C min.

Extract ventilation (6 AC/h min.)

Rooms under negative pressure.

Excitation

Switchgear

Rectifier/inverter

[42ºC. max.]

[20ºC. min]

[No humidity control]

AC systems with 100% fresh air facility for free cooling.

2 x 50% air handling units.

- 9.80 -


Area (s) Internal Condition Comment

Battery rooms 35ºC max.

20C min.

100% exhaust with duty/standby fans. Max 1% hydrogen concentration. Rooms under negative pressure.

Standby diesel generator room

[55ºC max.[

[No winter heating.]

Supply/extract ventilation for “normal” operation (DG off) plus boost ventilation (DG running) to DG. Manufacturer’s requirements.

Chiller building (hall) [42ºC max.]


AC system with 100% fresh air facility for free cooling. 2 x 50% air handling units.

Water treatment building (hall)

[42ºC max.]

[15C min.]

AC system with 100% fresh air facility for free cooling. 2 x 50% air handling units.

Fire pumphouse

Fuel oil pumphouse

[42ºC max.]


AC system with 100% fresh air facility for free cooling. Smoke extract system for DG driven fire pump, with fresh air inlet.

9.8.5.4 Sound levels

The sound levels in plant and occupied areas shall not exceed the following, with HVAC systems only in operation.

Switchgear Rooms. Relay Rooms NC50

Control Rooms. Offices. Prayer Rooms NC30

Workshops, Mess Rooms. Toilets. Corridors NC45.

Sound attenuators shall be provided in duct systems, as required to achieve the above sound levels.

9.8.5.5 Fresh air requirements

Fresh air shall be supplied for the following purposes.

a. Fresh air for occupied areas, minimum 15 litres/second/per person

b. Free cooling during periods of low ambient temperatures

c. Make-up air for exhaust ventilation systems

d. Building pressurization to exclude dust. Minimum fresh air supply shall not be less than 5 per cent of supply air volume.

Fresh air supplies shall be obtained from areas not subject to contamination from fumes. Air intakes shall be located at maximum available height, to reduce dust load.

- 9.81 -


9.8.5.6 Air filtration

Fresh air intakes on large systems shall have inertial sand filters with bleed fans and access sections. Small systems with fixed amounts of fresh air shall be provided with sand louvers.

All supply systems shall have two-stage air filtration, comprising washable primary panel filters and secondary bag filters, efficiency as required for the areas served.

9.8.5.7 Mechanical cooling

Mechanical cooling requirements shall be met by a central chilled water plant serving all cooling loads on the project. [Direct-expansion refrigeration plant may be used for projects where cooling load is less than 500 kW, or for small cooling loads remote from the central plant] In all cases, standby plant shall be provided for critical areas, as detailed below.

[Water-cooled chillers shall be used on sites where adequate water supplies are available to support cooling tower operation, otherwise chillers shall be air-cooled.]

Cooling towers shall be matched to chillers, and sized for [32°C] ambient wet bulb temperature. Condenser water pumps shall be matched to cooling towers. Air-cooled condensers shall be rated for [50C] ambient dry bulb temperature.

Three chillers, each rated at 50 per cent of design maximum cooling load, shall be provided, for two duty, one standby operation. Chillers shall be open centrifugal or scroll compressor (dual circuit) type, with capacity control to provide stable operation down to 10 per cent of design cooling load. All chillers shall be of US or European manufacture, and shall comply with the requirements of ARI550/590 – Water Chilling Packages using the Vapour Compression Cycle.

Refrigerant shall be R134a or equivalent. HFCF refrigerants shall not be used. Refrigerant piping and components shall comply with ASME B31.5 – Refrigerant Piping – and UL 207 – Refrigerant containing Components and Accessories.

The units and complete installation shall comply with ASHRAE 15 – Safety Code for Mechanical Refrigeration – and ASHRAE Guideline 3 for Refrigerant Leaks, Recovery, Handling and Storage Requirements.

Primary and secondary chilled water circuits shall be provided for all central systems, with primary pumps for each water chiller and duty/standby pumps for each secondary circuit. Secondary circuits shall be provided to match the chilled water temperatures required for the various systems. Air conditioning systems cooling coils shall be designed to give high return water temperatures under all load conditions, to reduce pump/pipe sizes and pumping costs. Service trenches shall be provided for distribution pipework to the various buildings around the site.

Central chilled water systems shall be complete with all necessary ancillary plant and systems as follows.

a. Pressurization/expansion vessels and pumps

b. Water treatment plant

- 9.82 -


c. Refrigerant handling and storage

d. Refrigerant leak detection

e. Condenser ball cleaning system.

The above plant, along with water-cooled chillers, primary/secondary pumps, control equipment etc. shall be accommodated in the Chiller Hall.

[Direct expansion refrigeration plant shall be air cooled, with condensers rated for 50C ambient dry bulb. All systems shall be ARI rated, and use HFC refrigerants. HFCF refrigerants shall only be used for small systems, with the permission of the Owner/Engineer.]

9.8.5.8 Emergency chillers

For sites using central chilled water systems, critical air-conditioning systems requiring 100 per cent standby plant shall be provided with emergency chillers for use in the event of failure of the central system.

Emergency chillers shall be air-cooled units, with screw or scroll compressors (dual circuit) and capacity control down to 20 per cent. Units shall be capable of matching system requirements at 50°C ambient temperature. Standards shall be as for the central plant chillers.

HCFC refrigerants shall not be used.

The emergency chillers shall be complete with pressurization unit, duplicate circulating pumps and interconnecting pipework to the central chilled water systems. Interconnecting pipework shall be complete with automatic changeover valves.

[The emergency chillers and associated air handling plant shall be powered from maintained electricity supplies available during blackout conditions.]

9.8.5.9 HVAC systems – general requirements

Air-conditioning systems shall be provided to serve areas classified as low temperature (26°C) and medium temperature (35°C and above). Except where areas have separate exhaust ventilation (eg battery rooms), low and medium temperature areas shall not be served from a common system.

All systems shall be designed and installed to be robust and reliable in service, easily maintained and of minimum life cycle cost.

Low temperature systems shall employ recirculation air ductwork where possible to reduce fresh air cooling loads. Fresh air supply shall be in accordance with the requirements of Section 9.8.5.5.

Medium temperature systems shall employ return air ductwork for use in summer (mechanical cooling) and up to 100 per cent fresh air for use in winter (free cooling). Fresh air supply in summer to be to be 5 per cent minimum, as indicated in Section 9.8.5.5.

- 9.83 -


Dedicated exhaust air systems shall be provided for battery rooms, toilets (minimum 10 AC/h extract), kitchens and chemical areas. Systems for battery rooms and toilets shall include duty/standby fans, with automatic changeover for duty fan failure and duty sharing.

Provision shall be made in all recirculation systems for venting of smoke/fumes after a fire incident.

Pressurization systems shall be provided for stairwells and corridors (escape routes) as required by the Fire Codes. Fans shall be powered from maintained electricity supplies, and operated through the fire detection system.

Systems shall be complete in all respects, including all necessary components, pipe and duct insulation, drains, instrumentation, motors, cabling etc. The following clauses indicate specific requirements for systems and for various components.

9.8.5.10 Ductwork

Ductwork shall be fabricated, installed and tested in accordance with the latest SMACNA Standards. General supply and extract system ductwork shall be of galvanized sheet steel construction. Irrespective of pressure/velocity classification, ductwork at low level in plant rooms and in areas subject to mechanical damage shall be constructed (as a minimum) to medium pressure standard.

All duct systems shall be complete with dampers to facilitate balancing. Splitter dampers will not be accepted. Access doors shall be provided as required for inspection/maintenance of dampers, fire dampers, instruments etc. Final connections to ceiling-mounted supply and extract terminals may be carried out in insulated flexible ductwork.

Extract system ductwork from battery rooms and chemical areas shall be of PVC construction.

High pressure ductwork shall be pressure/leak tested. Low and medium pressure ductwork need not be tested, except where located outdoors.

The following ductwork shall be insulated in accordance with the requirements of Specification Section .

a. Fresh air ductwork

b. Low Temperature supply and extract ductwork.

c. Medium temperature supply ductwork.

d. [Ductwork in Electrical rooms, where subject to condensation.]

- 9.84 -


9.8.5.11 Air filtration

All fresh air intakes on large central systems shall be provided with inertial type sand filters, with access sections behind. Small systems employing fixed volumes of fresh air shall be provided with sand louvers .

Primary and fresh air filters on all systems shall be permanent metal panel washable type, [dust spot efficiency 20 per cent]. A complete set of spare cells shall be provided for cleaning, along with coating fluids. [Washing facilities shall be provided, with Service water being used for cleaning.]

Secondary air filters on medium temperature systems serving plant areas shall be replaceable bag filters, [dust spot efficiency 50 per cent]. Secondary air filters on low temperature systems serving offices/control rooms/electronic areas shall be replaceable bag filters, [dust spot efficiency 90 per cent].

All bag filters shall be supported in proprietary mounting frames for front or side withdrawal. [The Contractor shall supply a sufficient number of replacement cells to last during the test periods and during the defects liability period, with one complete set being provided at that the end of the Defects Liability period.]

9.8.5.12 Fresh air conditioning

Central air-conditioning systems having humidity control may be provided with air handling units for fresh air supply. These units shall be provided with cooling coils and steam humidifiers to handle the full dehumidification/humidification load for the central system, with dew point control. Fresh air cooling coils shall have 10 per cent margin on heat transfer surface to cater for periods of abnormally high humidity. Face air velocity shall not exceed 2.0 m/sec.

Humidification shall be by electric powered steam generators with proportional control and steam lance injection.

9.8.5.13 Fire/smoke dampers

Fire dampers to UL Standards and NFPA-90A shall be provided on ductwork systems passing through firewalls and floors, and as required for compartmentation of gas fire suppression systems.

Dampers shall be operated by fusible link and (re-settable) damper motor, suitable for actuation through the fire detection system and fire damper control panel. Smoke dampers for clean agent fire suppression systems shall be motor operated/solenoid actuated for closing and opening purposes. Damper status shall be indicated on the control panel mounted adjacent to the Fire Control panel.

9.8.5.14 HVAC controls

All HVAC units and systems shall be provided with local control panels for local manual/automatic control. Data gathering panels (DGP) shall be provided as required (typically one per plant room/area) to interface controls and status indicators/alarms to a BMS for remote control.

- 9.85 -


All system status, alarms, set point indication etc shall be available at the remote station as well as at the local control point.

The BMS control station shall be located in the Main Control Room.

9.8.5.15 Power supplies

The Contractor shall include for all power and control cabling, MCC and controls for the complete HVAC systems.

[Dual redundant power supplies (normal ac and safe ac) shall be provided for systems requiring 100 per cent standby plant, including mechanical cooling.]

9.8.5.16 Inspection, testing and commissioning

In conjunction with the Owner/Engineer, the Contractor shall carry out all necessary inspections as the work progresses, and rectify defects as they are identified.

All HVAC systems and components shall be tested and commissioned by an independent specialist firm of Commissioning Engineers, on behalf of the Contractor. Systems shall be completed and tested to comply with the timescale required for the main plant installation and testing. The results of tests shall be submitted to the Owner/Engineer for approval, and included in the Operating and Maintenance manuals to be prepared by the Contractor.

Operating and Maintenance manuals and ‘As constructed’ record drawings shall be prepared by the Contractor as work proceeds, and completed documents and record drawings shall be submitted to the Owner/Engineer for approval in the quantity specified.

9.9 Subcontractors

The Contractor when submitting his Tender shall provide details of the subcontractors, or as a minimum a shortlist of the subcontractors, he proposes to use for the detailed design and construction of the civil works, together with a summary of works of a similar nature for which they have had design and construction responsibility.

9.10 Functional requirements

The design and layout of the civil works shall be directed to providing sufficient working space for plant and personnel, high standards in safety and working conditions for plant and personnel and to ensuring that maintenance of the installation over the life of the plant is minimal. The climatic conditions and Site location shall be taken into account in the design to meet these requirements.

The Contractor shall also ensure in his designs that noise limits for operational plant shall not exceed those specified.

- 9.86 -


9.11 Record drawings

‘As constructed’ record drawings shall be prepared by the Contractor as work proceeds and completed record drawings shall be submitted to the Owner/Engineer for approval in the quantity specified. Design and construction drawings prepared by CAD shall be made available and updated as the ‘as-constructed’ drawings also in electronic form on CD or DVD disks together with any software and license necessary for viewing and processing them. Three sets of record drawings on Civil Works shall be provided.

- 10.1 -


10. QUALITY CONTROL, INSPECTION AND TESTING

10.1 General

The whole of plant covered by this Contract will be subject to inspection and test by the Engineer during manufacture, erection and on completion. The Contractor’s costs associated with all tests and inspection shall be borne by the Contractor.

The Contractor and appointed subcontractors and suppliers are required to comply with the minimum requirements for quality assurance and quality control (inspection and tests) to be applied to goods and services as detailed below.

The Contractor and his nominated subcontractors shall work to defined quality assurance programmes compliant with ISO 9001. The Contractor shall list the quality level(s) proposed for his own, his subcontractor's and suppliers’ scope of supply. The Contractor shall supply the results of any recent audits and approvals held.

The Contractor shall undertake in respect of his subcontractors, where no such acceptable information is available or where the subcontractor has not been subject to an acceptable external quality audit within the previous 12 months, the carrying out a quality audit of that subcontractor to ensure that completion of the work will be compliant with the Contract requirements.

The Contractor shall have sole responsibility for ensuring compliance with the overall quality requirements of the Works, and shall ensure that subcontractor’s implement those quality control activities that are appropriate to the extent and nature of their supply.

The information supplied in response to the Quality Assurance requirements shall be deemed as part of the quality assurance arrangement and when agreed and accepted by the Owner shall form an integral part of the Contract.

The Contractor shall where required by the contract or other regulatory requirements appoint an approved body to carry out an independent design, inspection and test audit.

The Contractor shall establish and maintain a documented inspection system capable of producing objective evidence that all materials; manufactured parts and assemblies comply with the quality requirements of the Contract.

The Contractor shall establish a written procedure to identify and disposition any deviations identified during the course of manufacture, inspection and test etc.

The Contractor and his nominated subcontractors may be subject to quality audit by the Engineer.

The Contractor shall give all necessary help and assistance to the Engineer in carrying out such a quality assurance review. Such audits may take place during the tender evaluation period.

- 10.2 -


10.2 Extent of work

The Tenderer shall define in the Schedule the items within his extent of work; those items to be sub-contracted and propose the quality level attributed to each together with all items for which quality plans (inspection and test plans) will be submitted. The Tenderer shall identify the names and locations of the suppliers of all materials, equipment and services including the locations of companies within his own group of companies.

a. The Contractor's quality system shall include as a minimum, procedures used for controlling the following functions.

b. Inclusion on purchase orders of the necessary technical inspection and test details to meet the specified requirements and of the Engineer's right of involvement at the Contractor’s, subcontractors’ and suppliers’ works.

c. Availability at inspection points of applicable drawings, instructions, etc, and prompt removal of superseded documents.

d. Maintenance and calibration of suitable inspection and test equipment.

e. Incoming, in process and final inspection and inspection of packing and marking.

f. Means of identifying inspection status throughout manufacture.

g. Means of identifying and isolating raw materials and components not conforming to the Contract.

h. Provision of a written procedure to identify and disposition any requested deviations to the applicable national standards and specifications mentioned in the contract specification. All such items shall be reported to the Engineer via a non-conformance report.

i. Provision of complete inspection and test records.

10.3 Document submission

The Contractor shall submit for review, within 30 days of the Contract award a quality plan (inspection and test plans) defining the programme of quality control and inspection activities which he or his subcontractors/suppliers will perform in order to ensure that the procurement, manufacture and completion of the materials, equipment and plant complies with the specified requirements.

All submitted documents shall clearly identify the manufacturer and the item/sub-item of plant to which they apply.

The quality plan may be of any form to suit the Contractor's system, but it shall as a minimum:

a. Indicate each inspection and test point and its relative location in the production cycle including incoming, packing and site inspections.

- 10.3 -


j. Indicate where subcontractors' services will be employed (eg subcontractor NDT or heat treatment).

k. Identify the characteristics to be inspected, examined, and tested at each point and reference drawings, procedures and acceptance criteria to be used.

l. Indicate the inspection, test and hold points established by the supplier, subcontractor and Contractor, which require verification of selected characteristics of a document, item or process before this work can proceed.

m. Allow for witness, hold and review points to be established by the Engineer, which require his verification of selected characteristics of a document, item or process before this work can proceed.

n. Define or refer to sampling plans if proposed and where they will be used.

o. Where applicable, specify where lots or batches will be used.

p. Relevant acceptance criteria.

The Engineer will indicate the inspection requirements on the agreed inspection programme in accordance with the following:

i. Hold point – requires a mandatory inspection by the Engineer. This inspection or test shall be witnessed by the Engineer and further progress in manufacture shall not be made until the plant is approved by the Engineer.

ii. Witness point – inspection or test of material may be carried out by the Engineer at his discretion.

iii. Document review – certification of material and functional test shall be approved by the Engineer before despatch from the works.

Independently, the requirements of the Third Party Inspectorate shall be indicated in a similar manner prior to the submission of the Inspection Plan to the Engineer, for his approval.

The Contractor shall forward for review within 60 days of contract award for applicable items of equipment identified within quality plans, duplicate copies of:

A. Special process procedures covering the welding, heat treatment and non-destructive examinations of all pressure retaining and loading bearing fabrication welds and major castings including repair procedures. Procedures must include qualification records and acceptance criteria where applicable.

B. Inspection procedures for components and test procedures for sub-assemblies and complete assembly of the turbine shall be submitted to the Engineer for approval before assembly commences.

C. Test procedures for the witness testing of generators, excitation system, transformers, motors, frequency converters, HV and MV cables, HV, MV, and LV

- 10.4 -


switchgear, UPS and DC systems, protection equipment and circuit breakers and frequency converters.

D. Test procedures for the witness testing central and local control panels, SCADA and DCS equipment

E. Test procedures for the witness testing pumps, compressors and automated valves.

F. Purchase orders (unpriced) complete with technical specification and data sheets.

10.4 Inspection notification and right of access

In order to verify compliance with engineering procurement, manufacturing requirements and programmes, the Engineer shall have access at all reasonable times, to all places where materials or equipment are being prepared or manufactured and tested, including the works of the Contractor, subcontractors or suppliers of raw materials.

The Contractor shall advise the Engineer of the readiness of inspection at least 10 working days prior to a nominated witness or hold point. Work shall not proceed beyond a hold point without the written agreement of the Owner or his nominated representative. A common form of notification will be developed and agreed for general use on the contract.

Before giving such notice the Contractor is required to have completed all his internal controls, including that relative to the notification point and to have available documentation to that effect for the Engineer to review.

Request for waiver from contract quality requirements shall be made by the Contractor to the Engineer, as soon as it is established that an item of equipment as designed, or in manufacture, cannot be made to comply with a particular specified requirement. The subject item of equipment shall not be offered for final inspection until such waiver requests have been approved by the Engineer.

10.5 Inspection and tests

Inspection of materials or equipment may be made by the Engineer and could include the following activities:

b. Evaluation of the Contractor's system and approval of the quality plans.

c. Periodic monitoring to confirm the effectiveness of and the Contractor's, subcontractors’ and suppliers’ compliance with the established quality system procedures, inspection and test plans and inspection and test instructions.

d. Witnessing of inspections and tests and/or verification of inspection records to be carried out at the Engineer's discretion covering:

e. Compliance of raw material with specified requirements.

- 10.5 -


f. Compliance of manufactured parts, assemblies and final items with Specifications, drawings; standards and good engineering practice.

g. Periodic inspection of Contractor's design, manufacturing, installation work and the production of progress reports.

h. Witnessing of inspections and tests.

i. Packing for shipment including check for completeness of shipment, handling requirements, and case markings and identification.

The Contractor shall keep the Engineer informed in advance of the time of starting and of the progress of the work in its various stages so that arrangements can be made for inspection and for test. The Contractor shall plan the performance of inspection and tests so as to avoid the delaying of the work.

All of the required inspections and tests shall be made at the Contractor's expense, including the cost of all samples used. The Contractor shall be responsible for any additional costs incurred by the Engineer arising from the postponement, re-inspection or additional inspections or visits attributable to the Contractor, subcontractors or suppliers’ performance. The Contractor shall also provide, without charge, all reasonable facilities and assistance for the safety and convenience of the Engineer in the performance of his duties.

If the plant or any portion thereof fails under test to give the required performance, such further tests which are considered necessary by the Engineer shall be carried out by the Contractor and the whole cost of the repeated tests shall be borne by the Contractor. This also applies to tests carried out at subcontractor’s works.

10.6 Non-conformances

Non-conformances identified by the Engineer shall be notified to the Contractor by issue of the Engineer’s Non-Conformance Report. The Contractor shall receive and action all non-conformance reports and re-inspection shall not be notified until the completed non-conformance report, together with any applicable re-work or concession application, have been accepted by the Engineer.

Where applicable, rejection of materials, equipment and/or components will be made as promptly as practicable following any inspection or test involvement by the Engineer. Failure to inspect and or reject materials, equipment and/or components shall neither relieve the Contractor from responsibility for such items which may not be in accordance with the specified requirements, nor impose liability for them on the Engineer.

The Contractor and subcontractors quality assurance programme shall identify and isolate raw materials and components not conforming to the Design Book. All such items shall be reported to the Owner via a non-conformance report.

Approval of a concession application is the prerogative of the Engineer and approval of a particular case shall not set precedent.

- 10.6 -


The Engineer shall have complete authority to accept or reject any equipment or part thereof considered unsatisfactory and/or not in accordance with the contract requirements.

The witness of any inspection and tests by the Engineer of any components or lots thereof does not relieve the Contractor of any responsibility whatever regarding defects or other failures which may be found before the end of the warranty period.

10.7 Quality control records, certificates and certificates of conformance

At the end of each visit to a manufacturer to carry out quality control activity, the Engineer’s Representative will complete a Quality Control Record and hand one copy to a responsible representative of the Manufacturer.

The Quality Control Record (QCR) will identify the item inspected, the stage of manufacture, and the nature of the QC carried out, and will list all points which require remedial action by the manufacturer, before the subject item can be released.

When each item of equipment is ready for despatch from the place of manufacture and the Engineer has verified compliance with specified requirements up to that point, a Quality Control Certificate will be issued to the Contractor.

The Quality Control Certificate (QCC) will identify the item to which it applies and will release that item from the Engineer’s control only. The QCC does not constitute any form of acceptance of the item by either the Engineer or the Owner.

The Contractor shall provide a Certificate of Conformance confirming compliance with the Contract requirements and as detailed in the manufacturing record data book.

Sets of all test records, test certificates and performance curves, whether or not they have been witnessed by the Engineer, shall be supplied for all tests carried out in accordance with the provisions of this Contract.

Sets of all test certificates shall be endorsed with sufficient information to identify the material or equipment to which the certificates refer, and shall carry in the top right hand corner the following reference:

Owner’s name Project title Engineer’s reference number.

All test documentation shall be in the English language.

No materials or equipment shall be shipped to the Site until all tests, analysis and inspections have been made and the Contractor's Certificate of Conformance has been reviewed and released by the Engineer; or unless otherwise agreed by the Engineer.

- 10.7 -


10.8 Specific tests and inspections

Refer to Schedule G for details of specific tests and inspections.

- 11.1 -


11. COMMISSIONING, START-UP AND TESTS ON COMPLETION

11.1 General

This section describes general conditions for commissioning, start-up and testing of the plant for operation on fuel gas with fuel oil as back-up.

The Contractor shall be responsible for functional testing, commissioning, performance testing and reliability testing of the complete plant. The reliability test shall be carried out after the Performance Guarantee Tests.

The Contractor shall be responsible for providing all the necessary permanent and temporary equipment, materials, consumables (excluding fuel) and services to meet his commitments with regard to this phase of the work.

To the maximum extent possible, the tests will make use of the permanently installed instrumentation. Where possible this same instrumentation shall be suitable for use for the performance tests. The permanently installed instrumentation shall be suitable for gas turbine performance benchmark tests. The installed instrumentation shall have accuracy levels to meet the requirements of the relevant performance Codes and Standards.

11.2 Commissioning

11.2.1 Commissioning procedures

[6] months prior to the start of commissioning, the Contractor shall submit for review a site commissioning record system that provides for all commissioning procedures and activities that shall be performed during the works to be identified and readily traceable.

Each commissioning procedure shall include the following information as a minimum:

a. Objective and procedure

b. Scope of procedure

c. Reference documents, P&IDs and drawings

d. Prerequisites to the commissioning

e. List of relevant check sheets with date completed and signing off procedure

f. Check sheets with sections for signing off by construction, commissioning, and Engineer personnel.

Where check sheets include items such as checking of alignment, vibration etc then the reference documents shall clearly indicate the criteria against which these parameters can be accepted. Vendors documentation is acceptable for this purpose but must be adequately referenced on the check sheet and available.

A specific check sheet shall be provided for each component to be commissioned.

- 11.2 -


Packages of documentation shall be issued for each system of the work as they become mechanically complete.

The records shall be sufficiently detailed to show all checks performed on systems, items of plant, instrumentation and controls, and protection. It is envisaged they will cover all checks carried out prior to equipment and systems being put into service and all functionality test thereafter.

The Contractor shall prepare maintain and update a “Punch list” of all items which are incomplete or defective and which require remedial action.

The Contractor shall prepare a detailed test and commissioning programme for issue to appropriate parties on a regular basis to illustrate commissioning progress against planned complete dates.

The Contractor shall establish a safety and permit-to-work system for the Site to ensure that the plant is placed into and taken out of service in a safe and controlled manner so that the integrity of adjacent construction work can be undertaken in a safe manner.

11.2.2 Precommissioning

The Contractor shall be responsible for performing mechanical testing and functional testing of all plant to confirm compliance with design basis and operating criteria. During this period the Contractor shall undertake all installation checks, preliminary mechanical and electrical checks, pressure testing, flushing and cleaning of equipment and pipework, proving the integrity of all connections (mechanical and electrical), safety systems and verification that all plant is functionally complete. These tests shall include, but are not limited to, open and short circuit testing of the generator, verification and checking of all protection settings, checking of plant inter-tripping circuits (including GT trips, and GT fired shutdown) and inter-tripping circuits between the plant and the grid equipment.

Where plant components form part of a system, then each component comprising that system shall be similarly inspected and tested prior to placing the system into service. Static tests to demonstrate interactive operation of components within the system shall also be completed prior to charging or energizing the system for the first time.

The Contractor shall also be responsible for producing a Quality Plan to detail all testing requirements for the plant.

The Engineer shall be given the opportunity to witness all such testing and inspection.

All checks, inspections and test activities and results shall be logged by the Contractor on suitable pro formas and shall be available for inspection by the Engineer at all times during the course of the Project. Copies of this documentation shall be passed to the Engineer on completion of the Project.

The Contractor shall provide the Engineer with a list of all items which are incomplete and/or not fit for purpose and for which remedial action has to be taken.

- 11.3 -


11.2.3 Commissioning

The Contractor shall be responsible for carrying out all the commissioning work associated with bringing the plant to a condition where it is ready to undergo its reliability and performance tests.

Prior to the start of commissioning, the Contractor shall ensure that the Engineer has been provided with the latest edition of all relevant documents and drawings.

Once the component or system is charged, energized or otherwise made live, the Contractor shall conduct further tests to demonstrate that the system and its constituent components function collectively as designed, that individual components operate at varying loads under steady state conditions within their stated operating parameters, and that the components and system respond correctly to transient conditions. The Contractor shall undertake whatever adjustments are necessary to achieve the best level of plant reliability, capacity and performance.

In addition to the above, the following tests shall be carried out:

a. Fuel systems

All fuel supply systems shall be tested to demonstrate satisfactory fuel pressure and flow control under all operating conditions including start-up, shutdown and full load rejection. This applies to both the fuel gas and fuel oil systems.

b. Control function tests

When the Contractor has completed all commissioning of all the local and remote/supervisory control functions, every function shall be demonstrated to have been commissioned, calibrated and loop tested. Tests to verify the correct and safe operation of the plant will also be conducted to a protocol agreed between the Contractor and the Engineer.

c. Overspeed tests

Overspeed tests shall be made on the gas turbine, to the turbine manufacturer's standard procedure.

d. Load rejection test

It shall be demonstrated that the instantaneous rejection of full load from the gas turbine will not cause an overspeed trip of the unit.

11.2.4 Tests on completion

The object of these tests is to demonstrate the fitness for purpose of the plant prior to take-over by the Owner. The scope of tests shall include the following and any other tests the Engineer may reasonably require to demonstrate the fitness for purpose of the plant:

- 11.4 -


a. demonstration of starting, shutdown and transient characteristics under both hot and cold conditions. This shall include a successful demonstration of the ‘one push button’ start up and shutdown of the plant

b. performance of the governing system and protective devices

c. grid compliance testing including MVAr capability, frequency response and AVR testing

d. unit load control tests.

The Contractor shall carry out the Tests on Completion. The plant shall be operated by the Owner under the supervision of the Contractor. The Tests on Completion shall be satisfactorily passed prior to commencement of the Performance Tests.

11.2.5 Start up guarantee tests

The GT units shall be started both independently and simultaneously from their cold, warm or hot condition and shall be shut down in a simultaneous sequence. The time elapsed from start initiation to base load for each gas turbine and for the complete block shall be recorded and compared with the guaranteed maximum start times provided by the Contractor.

11.3 Guarantee and performance tests

The Works will not be taken over by the Owner until satisfactory completion of all tests. The Performance Tests shall be satisfactorily passed prior to commencement of the Reliability Test. The Noise Test and the Environmental Tests may be undertaken in conjunction with the Performance Test. However, the emission tests shall be performed at the same time as the Performance Tests. The Performance Tests and Reliability Test shall be undertaken with operable and calibrated CEMS equipment. Failure of the CEMS will invalidate a Performance Test or Reliability Test.

The scope of guarantee and performance tests shall include the following:

a. performance guarantee tests (output, heat rate and environmental).

b. reliability test run.

11.3.1 Output and heat rate performance guarantee tests

11.3.1.1 General

The Contractor shall carry out performance tests to demonstrate that the plant complies with the contractual performance guarantees. The reliability test shall be carried out after the Performance Guarantee Tests.

Power output and heat rate of the overall power plant shall be determined in accordance with ASME PTC 22 or ISO 2314.

The Contractor shall formulate the testing procedure for carrying out performance tests on the plant with regard to identifying scope of tests, references and definitions, guiding principles,

- 11.5 -


preparation for tests, operating conditions for tests, instruments and methods of measurements, computation of results and test report.

The precise nature of the tests together with testing procedures and programmes, accuracy of measurement etc shall be provided by the Contractor and shall be agreed between Contractor and Engineer prior to execution of the Contract to facilitate agreement between the Contractor and the Engineer at an early stage in the contract programme.

Whilst the performance tests shall be carried out on the plant as a whole and not individual plant items, this shall not preclude the Contractor from the responsibility of undertaking the necessary demonstration performance tests on major individual items of plant to either verify satisfactory operation or identify any shortfall in individual plant performance.

Unless otherwise agreed each individual guarantee performance test shall be carried out for a period of 1 continuous hour, divided into three consecutive 20 minute evaluation periods.

The performance guarantee tests will consist of output and heat rate tests at full load on both fuel gas and fuel oil. The performance guarantee tests will be performed after completion of commissioning tests but before the reliability test as described in later in this section.

11.3.1.2 Conditions of test

During the contractual guarantee performance test the plant mode of operation shall be:

a. the plant shall be operated at full load

b. all standby auxiliaries shall be operational

c. variations exceeding steady state conditions shall invalidate the test run and shall be repeated

d. emissions shall be maintained within guaranteed criterion, as measured by the calibrated CEMS equipment, throughout the performance tests.

The facility shall be operated in a normal mode which is representative of a long term operating configuration with all equipment operating as designed and within specification and alarm limits consistent with good power generation industry practice. No normally operating systems should be taken out of service including by passing or suppressing of alarms unless specifically allowed in the test procedure.

11.3.1.3 Correction curves

The tests results recorded during the Performance Test shall be corrected, as applicable, to those which would have been achieved had the test been carried out at the guarantee basis conditions by using agreed correction curves. Formulae describing the correction curves shall also be provided.

- 11.6 -


These correction curves and formulae shall be limited to:

a. correction for ambient temperature

b. correction for humidity

c. correction for barometric pressure

d. correction for fuel calorific value and C/H ratio

e. correction for power factor

f. correction for grid frequency.

The correction curves and formulae shall be provided in the Performance Test Procedure, and included with the Tender.

11.3.1.4 Metering

The net OCGT plant output for the performance guarantee tests shall be measured using the tariff meters. The meters shall be capable of displaying kilowatt hours for the duration of the test.

All auxiliary loads that would normally be operating at the Guarantee Point shall be in operation during the tests. A list of auxiliary loads shall be provided with the Tender documents and in the Test Procedure.

The fuel meters provided shall be of suitable accuracy for performance testing according to the appropriate test code.

Procedures for measurement of other parameters such as ambient temperature, barometric pressure, relative humidity etc shall be fully detailed in the Performance Test Procedure.

No test-measuring orifice plates, nozzles or venturi tubes shall be installed without the approval of, and witnessing by, the Owner.

11.3.1.5 Fuel analysis

The Contractor shall ensure that an analysis of the fuel before, during and after the test is performed and that this data shall be submitted with other relevant test information in the final test report. The Contractor shall supply the necessary apparatus for taking and containing the fuel samples. Three separate samples shall be taken at each of the three sampling periods. One of each set of three samples shall be analysed by an independent authority and the costs of these analyses shall be borne by the Contractor. One sample of each set of three shall be properly labelled and handed over to the Owner. One set shall be maintained by the Engineer in case of dispute of the results.

11.3.1.6 Instrument test measurement uncertainty

Just prior to the Performance Test every test instrument required for the measurement of test data shall be checked and recalibrated if necessary.

- 11.7 -


All instruments used in the Performance Test shall be of the standard, quality, and accuracy suitable for performance testing as detailed in the Performance Test Procedure.

A pre-test uncertainty analysis shall be carried out to confirm that the selected instruments and test design shall provide test uncertainties on corrected heat rate and power no greater than those given in the Test Code. A post-test uncertainty analysis shall also be carried out to validate the test, the results of which shall be included in the test report. The details and results of the pre-test and uncertainty analyses shall be included in the test procedure.

Instruments for critical measurements shall be calibrated using standard reference sources or shall have been previously calibrated and certified by independent nationally or internationally approved calibration authorities.

Calibration certificates shall be provided for the test instruments at the time of test. The costs involved in preparation of calibration certificates will be to the Contractor's account.

The corrected test result of net heat rate and net power output shall have no measurement uncertainty correction applied. The Contractor's guaranteed performance figures shall be quoted accordingly.

11.3.1.7 Performance tolerances

The corrected test result of net heat rate and net power output shall have no tolerance correction applied. The Contractor's guaranteed performance figures shall be quoted accordingly.

11.3.1.8 Performance testing procedure

A Performance Test Procedure document shall be prepared by the Contractor for approval by the Owner and shall be submitted to the Owner in its final form not less than six months prior to the programmed Test Date.

The Performance Test Procedure shall be a full and detailed procedure based on ASME PTC 22 or ISO 2314 and in accordance with the procedures, scope and details contained in this Specification. Curves and correction factors to be used for the Performance Tests shall be based on the equipment vendor's standard correction curves. The curves used shall be those included in the Contract.

The Performance Testing Procedure shall be in accordance with the pre-Contract Performance Test Procedure and will be mutually agreed between the Contractor and the Owner or Owner's representative at an early stage in the contract programme. The Performance Test Procedure shall include all calculations showing the use of all correction curves and factors for each parameter. The Performance Tests shall be witnessed by the Owner and the evaluated test results submitted to the Owner for approval. The format for the Performance Testing Procedure will generally be as follows:

a. Scope of tests

- 11.8 -


b. Guiding principles

i. test dates and timetable

ii. preparation for tests

iii. method of tests

iv. plant mode of operation

c. Testing conditions

v. operating conditions

vi. constancy of test conditions

vii. maximum permissible variations in plant operating conditions

viii. duration of tests

d. Instruments and method of measurement

ix. define plant test parameters

x. list of test instruments

xi. calibration of test instruments (class of accuracy)

xii. instrument test measurement uncertainty

xiii. commercial panel instruments

e. Computation of test results

i. data acquisition system log sheets

ii. commercial panel instrument log sheets

iii. frequency of readings

iv. observers and labour

v. specified requirements and guarantees

vi. fuel calculations

vii. correction curves and data

viii. instrument list and diagram of test measuring points

ix. diagram of electrical test measuring equipment

- 11.9 -


x. instrumentation for electrical output

xi. current and voltage transformers.

11.3.2 Environmental performance guarantee tests

During the output and heat rate performance tests and the reliability test, the Contractor shall undertake witnessed emission tests to prove that the plant meets all relevant environmental requirements/planning consents. During the reliability test, the Contractor shall undertake witnessed noise tests to prove that the plant meets all relevant noise requirements.

The emissions compliance test will be conducted by an approved firm, experienced with such testing. The CEM system shall be calibrated against the test results. The duration of the emissions test shall be a minimum of 4 hours. Normal plant start up and operating procedures should be used in operating the unit during the tests. All plant systems will be in automatic control. The gas turbines shall be operated at base load, with tests to be carried out on fuel gas and fuel oil.

Measurement of noise levels at the site boundaries shall be measured in accordance with the approach defined in ISO 6190:1999 “Acoustics - measurement of sound pressure levels of gas turbine installations for evaluating environmental noise - survey method”.

Prior to testing a measure shall be made of the background noise levels without the power plant operating. Measurements shall preferably be made at night in a period of low background noise levels from other sources and minimum off-site vehicle movement.

The measurement equipment shall comply with ANSI S1.4 precision standards. The test method shall be in accordance with BS 4142:1007 or equivalent.

For work area noise acceptance tests, equivalent continuous levels shall be obtained at a minimum distance of 1 m from the surface of equipment, acoustic enclosures, or room boundaries.

The results of the tests shall be fully reported together with operating conditions of the equipment, meteorological conditions, noise measurements, instrument locations and instrument details.

Any increase in noise levels above that allowed in the Contract shall be investigated and should these be shown to be because of noise emanating from new plant, then the Contractor shall remedy same at his own cost by the installation of sound attenuation measures. Repeat tests shall then be carried out to demonstrate that the remedial works have been successful in eliminating the noise problem.

Tests shall be undertaken on effluent and gaseous emission levels to ensure compliance with the stipulated planning consents.

11.3.3 Reliability test

The reliability of the plant, complete with all ancillary plant, equipment and services required for the full, safe and efficient operation, shall be proved by starting fully automatically and by operating within the limits of output specified, and either continuously or intermittently as may be more

- 11.10 -


convenient for the working of the station without interruption of any kind for a period of 7 consecutive days (168 hours), operating on fuel gas.

The Contractor will be permitted to make any minor adjustments, which may be necessary, provided that such adjustments do not in any way, interfere with or prevent the commercial use of the plant by the Owner, or result in reducing the output, decreasing the efficiency or exceeding the environmental limits.

Should any interruption occur in any portion of the Plant, due to or arising from faulty design, material or workmanship, a new reliability test period of 7 days shall commence after the Contractor has remedied the defect.

An interruption is defined as:

a. Any plant failure resulting in a reduction in generation capacity from the requested power output.

b. Any deviation from the requested power output at of more than ± 2.5 per cent of requested output

c. Operation of equipment in manual mode which normally is operated in automatic mode

d. Switching over to the redundant auxiliary system because of failure

e. Failure of plant to start.

If for reasons beyond the control of the Contractor, the reliability test is interrupted, the test shall resume as if the interruption had not occurred.

11.4 Test records

The Contractor shall be responsible for supplying to the Owner two copies of all test documentation for precommissioning, commissioning, performance and reliability tests for the complete plant.

The Contractor shall promptly prepare and submit a detailed test report to the Owner/Engineer within 5 business days of completion of any test. The test report shall include the test procedure, description of any deviations from the test procedure of unusual event(s), which occurred during the test, copies of test data sheets, calculated results, copies of lab analyses, and copies of instrument calibration records.


GAS TURBINE POWER STATION VOLUME 2 TECHNICAL SCHEDULES AUGUST 2004

- 1 -

LIST OF REVISIONS

Current Rev.

Date Page affected

Prepared by


Checked by (quality

assurance)

Approved by

A

Aug 2004

All


J SAMS S WATT

J LIDDLE

MA MITCHELL

J LIDDLE

Original

Aug 2004

All

REVISION DETAILS


A

Aug 2004

All

Final issue as Document No. 62010/IPA/000001 Rev A


(i)

CONTENTS

Page

LIST OF ABBREVIATIONS

SCHEDULE A SITE PARTICULARS A1-A5

SCHEDULE B DATES OF DESPATCH, DELIVERY TO SITE AND COMPLETION B1

SCHEDULE C1 MANUFACTURERS GUARANTEE PARTICULARS C1.1-C1.8

SCHEDULE C2 MECHANICAL SCHEDULES C2.1-C2.44

SCHEDULE C3 ELECTRICAL TECHNICAL SCHEDULES C3.1-C3.14

SCHEDULE C4 CONTROL AND INSTRUMENTATION TECHNICAL SCHEDULES C4.1-C4.14

SCHEDULE C5 CIVIL SCHEDULES C5.1-C5.5

SCHEDULE D SUPPLIERS OF MATERIALS, MANUFACTURERS, PLACES OF MANUFACTURE TESTING AND INSPECTION D1-D5

SCHEDULE E DRAWINGS AND DOCUMENTATION E1-E14

SCHEDULE F VARIATIONS FROM SPECIFICATION F1

SCHEDULE G TESTS AND INSPECTIONS G1-G17

SCHEDULE H LIST OF SPARE PARTS AND CONSUMABLES H1-H2

SCHEDULE J LIST OF SPECIAL TOOLS AND EQUIPMENT J1

____________________________


- 1 -

LIST OF ABBREVIATIONS % percent °C degrees Celsius A ampere ac alternating current AGI above ground installation AVR automatic voltage regulator barg bar gauge BMS Building Management System BoP balance of plant BS British Standards C&I control and instrumentation CCGT combined cycle gas turbine CCR central control room CCTV closed circuit television CO carbon monoxide CT current transformer dB decibel dc direct current DCS distributed control system DGP data gathering panels EHV extra high voltage EMC electromagnetic compatibility EN Euro Norme EPA Environment Public Authority EPC engineer, procure, construct EPR ethylene propylene rubber EWS engineer’s workstation GIS gas insulated switchgear GMT Greenwich mean time GPS global positioning system GRP glass reinforced plastic GT gas turbine HCFC single hydrochlorofluorocarbon compound HMI human machine interface HRSG heat recovery steam generator HV high voltage HVAC heating ventilation and air-conditioning Hz hertz I/O input/output IEC International Electrotechnical Commission IEEE Institute of Electrical and Electronics Engineers IP International Protection IPB isolated phase busbar ISDN integrated service digital network ISO International Standards Organisation kg kilogram km kilometre kV kilovolt LSF low smoke and fume LV low voltage m metre mA milliampere mb millibar MCB miniature circuit breaker MCC motor control centre mg milligram MICC mineral insulated copper cable mm millimetre


- 2 -

mm2 millimetre squared MV medium voltage MVA megavolt ampere MVAr megavolt-ampere reactive MW megawatt MWe megawatts electrical NCC National Control Centre Nm3 normal metres cubed NOx oxides of nitrogen O2 oxygen OCGT open cycle gas turbine ONAF oil natural air forced ONAN oil natural air natural PA public address PABX private automatic branch exchange PCS plant control system PSTN public switched telephone network PTZ pan-tilt-zoom PVC polyvinyl chloride RH relative humidity rms root mean square RSO recurrent surge oscillogram RTD resistance thermometer detector SF6 sulphur hexafluoride SFC static frequency converter SMACNA Sheet Metal and Air Conditioning Contractors National Association SO2 sulphur dioxide SOE sequence of events SPN single phase neutral TEWAC totally enclosed water cooled TPN three phase neutral TV television UHF ultra high frequency UPS uninterruptible power supply UV ultra violet V volt VCR video cassette recorder VDE Verband Der Elektrotechnik Elektronik Informationstechnik e.V VDU visual display unit VOC volatile organic compounds VT voltage transformer WB World Bank WTP water treatment plant XLPE cross linked polyethylene XLPE cross linked polyethylene


- A1 -

SCHEDULE A SITE PARTICULARS

Item No

Description Particulars

1. SITE AMBIENT DATA

1.1 Site location

1.2 Site elevation (above sea level) m

Design ambient conditions (Site rating):

1.3 Design ambient pressure mbar

1.4 Design ambient temperature (dry bulb)

1.5 Design relative humidity %

Ambient temperature (dry bulb):

1.6 Highest maximum (recorded) °C

1.7 Maximum yearly average °C

1.8 Maximum daily average °C

1.9 Design maximum temperature °C

1.10 Max. metal temperature under the sun °C

1.11 Lowest minimum (recorded) °C

1.12 Design minimum temperature °C

Relative humidity:

1.13 Maximum (recorded at 40°C) %

1.14 Minimum %

1.15 Yearly average %

Precipitation:

1.16 Mean annual rainfall mm

1.17 24 hour rainfall (once in 30 years) mm

Wind speed:

1.18 Average wind speed m/s

1.19 Design wind speed (3 second gust) m/s

Document No. 62010/IPA/000001 Rev A 0654S110_SCHEDA/S1/5/PMO

- A2 -

Item No


Air quality:

1.20 Air pollution

Seismic:

1.21 Seismic Zone Classification

2. FUEL GAS DATA

2.1 Fuel gas type/designation

2.2 Supply Conditions: Min Max Design

2.3 Supply pressure barg

2.4 Supply temperature °C

2.5 Density at NTP kg/m3

2.6 Specific heat (Cp) at supply temp. J/kg/K

2.7 Lower Heating Value (LHV) kJ/kg

2.8 Higher heating Value (HHV) kJ/kg

2.9 Water dew point °C

2.10 Dust (content and particle size) % wt/µ

2.11 Sodium and potassium ppm(wt)

2.12 Vanadium ppm(wt)

2.13 Argon mole %

2.14 Helium mole %

2.15 Hydrogen mole %

2.16 Oxygen mole %

2.17 Water mole %

2.18 Hydrogen sulphide mole %

2.19 Nitrogen mole %

2.20 Carbon monoxide mole %

2.21 Carbon dioxide mole %

2.22 Methane mole %

2.23 Ethane mole %


- A3 -

Item No


2.24 Propane mole %

2.25 Iso-butane mole %

2.26 Normal butane mole %

2.27 Iso-pentane mole %

2.28 Normal pentane mole %

2.29 Hexane mole %

2.30 Heptane mole %

2.31 Nonane mole %

2.32 Decanes + mole %

2.33 Ethylelne mole %

2.34 Propylene mole %

2.35 Butylene mole %

2.36 Pentene mole %

2.37 Benzene mole %

2.38 Toluene mole %

2.39 Xylenes mole %

3. FUEL OIL DATA

3.1 Fuel oil type/designation

3.2 Codes/standards

Supply conditions: Min Max Design

3.3 Supply pressure barg

3.4 Supply temperature °C

3.5 Density at 15°C kg/m3

3.6 Kinematic viscosity at 40°C m2/s

3.7 Pour point °C

3.8 Flash point (Pensky Martin closed) °C

3.9 Lower heating value kJ/kg


- A4 -

Item No


3.10 Sulphur % wt

3.11 Carbon residue (Ramsbottom on 10% residue)

% wt

3.12 Water content % wt

3.13 Sediment (filterable) % wt

3.14 Ash ppm(wt)

3.15 Sodium plus potassium ppm(wt)

3.16 Vanadium ppm(wt)

3.17 Lead ppm(wt)

3.18 Calcium ppm(wt)

4. WATER SUPPLY DATA

4.1 Raw water source

4.2 Raw water type/designation

Raw water analysis Min Max Design

4.3 Neutral electricity conductivity micro ohms @ 20°C

4.4 Calculated TDS based on 0.60 ppm/microhm

4.5 pH

4.6 Free causticity as NaOH mg/kg

4.7 Total causticity as NaOH mg/kg

4.8 Equivalent mineral acidity as CaCO3 mg/kg

4.9 Total alkalinity as CaCO3 mg/kg

4.10 Total hardness as CaCO3 mg/kg

4.11 Calcium hardness as CaCO3 mg/kg

4.12 Magnesium hardness as CaCO3 mg/kg

4.13 Sodium as CaCO3 mg/kg

4.14 Potassium as CaCO3 mg/kg

4.15 Sulphate as CaCO3 mg/kg


- A5 -

Item No


4.16 Chloride as CaCO3 mg/kg

4.17 Nitrate as CaCO3 mg/kg

4.18 Iron as Fe mg/kg

4.19 Aluminium as Al mg/kg

4.20 Barium as Ba mg/kg

4.21 Ammonia as NH3 mg/kg

4.22 Permanganate value as KMnO4 mg/kg

4.23 Total organic carbon as C mg/kg

4.24 Reactive silica as SiO2 mg/kg

4.25 Non-reactive silica as SiO2 mg/kg

4.26 Suspended solids mg/kg

4.27 Detergents mg/kg

4.28 Phosphates as Na3PO4 mg/kg

4.29 Total ammoniacal nitrogen (free and saline) as NH3

mg/kg

5. ELECTRICAL SYSTEM PARAMETERS

5.1 Transmission system:

5.2 Nominal voltage V

5.3 Voltage variation %

5.4 Nominal frequency Hz

5.5 Frequency variation %

5.6 Maximum fault infeed from grid

5.7 Minimum fault infeed from grid

5.8 Generator transformer vector group


- B1 -

SCHEDULE B DATES OF DESPATCH, DELIVERY TO SITE AND COMPLETION

1. Times from date of Contract award Calendar months

2. Within which first materials will be ready for inspection and testing

3. Within which the Contractor will require access to site

4. Within which the first materials will be delivered to site

5. Within which the open cycle GT generator unit will be delivered to site

a. GT1

b. GT2

6. Within which the Black Start diesel will be delivered to site

7. Within which the connection to the gas system is required

8. Within which the connection to the grid system is required

9. Achievement of:

a. First fire GT1

b. First fire GT2

10. Within which the Works will be completed, tested and ready for take over

Document No. 62010/IPA/000001 Rev A 0654S120_SCHEDB.DOC/S1/1/PMO

- C1.1 -

SCHEDULE C1 MANUFACTURERS GUARANTEE PARTICULARS

C1.1 Plant performance guarantees

The Tenderer is required to complete the following schedules associated with [ ] Power Station, under the conditions as stated in the Specification and based on the following:

C1.1.1 Plant output and heat rate guarantees

The Contractor guarantees that when the plant is operated and tested in accordance with the requirements of the Contract and the conditions as defined below, the following guarantee parameters shall be met:

Fuel gas Operation Fuel oil operation

Base load Net plant output [NPO] (kW)

Base Load Net plant heat rate [NPHR] (kJ/kWh) [based on LHV of the fuel]

Firing temperature at which the above guarantees will be met * °C

* During the performance test and prior to Taking Over, the gas turbine firing temperature shall be verified by the Contractor.

Net plant output is measured at the tariff meter on the HV side of the main transformers.

The net plant heat rate is defined as:

kWhkJNPO

ctLHVmNPHR pff /

]*)15([3600 15 −+⋅

⋅=

where

cp = average specific heat capacity of fuel in the temperature range 15°C to tf (kJ/kg°C)

LHV15 = lower heating value of fuel at 15°C, (for gas, calculated according to ISO 6976 (kJ/kg))

mf = mass flow of fuel (kg/s)

tf = fuel temperature at delivery point (°C)

Document No. 62010/IPA/000001 Rev A 0654s131_SchedC1.doc/S1/8/PMO

- C1.2 -

C1.1.2 Table of base reference conditions (site rating) – To be completed by the Engineer

The guarantee performance shall be based on the following base reference conditions :

Item No

Parameter Value

1. Ambient conditions

1.1 Site Datum Elevation* m [ ]

1.2 Barometric pressure mbar [ ]

1.3 Air dry bulb temperature °C [ ]

1.4 Relative humidity % [ ]

2. Fuel oil

2.1 Fuel analysis Schedule A

2.2 Calorific value (LHV) MJ/kg [ ]

2.3 Supply temperature °C [ ]

3. Fuel gas

3.1 Fuel analysis Schedule A

3.2 Calorific value (LHV) MJ/kg [ ]

3.3 Supply temperature °C [ ]

3.4 Pressure (at site boundary) barg [ ]

4. Electrical conditions

4.1 Frequency Hz [ ]

4.2 Power factor [lagging] [ ]

* m Refers to level above Admiralty Chart Datum.

C1.1.3 Test conduct

For requirements regarding conduct of performance tests, refer to Section 11 of this Specification.

C1.1.4 Correction curves

The Contractor shall submit for approval, curves indicating the variation in Net Plant Output and Net Plant Heat rate with the above conditions. The approved versions of these curves will be used to correct the acceptance test results from test to guarantee conditions.

The Contractor shall confirm that the correction curves shall, as a minimum be valid for the range of conditions as defined in Schedule A.


- C1.3 -

C1.2 Emissions guarantees

C1.2.1 Gaseous emissions

The Contractor guarantees the following data relating to maximum gaseous emission levels.

Parameter Unit Gas Fuel Liquid Fuel

Outlet NOx * mg/Nm3

Sulphur dioxide * mg/Nm3

Particulate matter mg/Nm3

Water injection rate kg/s N/A

Guaranteed gas turbine load range at which the above emission levels can be maintained

%

* at 15% oxygen, dry, 0°C, 1 atm

C1.2.2 Aqueous emissions

The Contractor guarantees the following maximum aqueous emission levels at the point of discharge from the Works, with the plant operating at base load conditions.

Parameter Unit Value

pH range

total suspended solids mg/l

oil and grease mg/l

total residual chlorine mg/l

Chromium, copper/iron/zinc mg/l

Temperature rise ** °C

** The difference in temperature between the inflow and outflow points of water.


- C1.4 -

C1.2.3 Noise emissions

The Contractor guarantees the following maximum Sound Pressure Levels (SPL) for all operating and shutdown conditions of the Plant.


Equipment noise level (measured at 1 metre from source)

dB(A)

Far field noise level (site boundary) dB(A)


- C1.5 -

C1.3 Water treatment plant performance

C1.3.1 Potable Water

The Contractor guarantees that the following potable water parameters will be met under all operating conditions:

Parameter Unit Maximum value

Sodium as Na mg/l

Potassium as K mg/l

Calcium as Ca mg/l

Magnesium as Mg mg/l

Chloride as Cl mg/l

Sulphate as SO4 mg/l

Copper as Cu mg/l

Iron as Fe mg/l

TDS mg/l

pH range

The Contractor guarantees the following treatment plant performance parameters:


Continuous capacity (net) m3/day

Auxiliary power consumption

kW


- C1.6 -

C1.3.2 Demineralization unit

The Contractor guarantees that the demineralized water product at the outlet of the water treatment plant will be met under all operating conditions:

Parameter Unit Maximum value

Specific conductivity @ 25°C

µS/cm

Sodium as Na mg/l

Chloride as Cl mg/l

Sulphate as SO4 mg/l

Silica as Si mg/l

Copper as Cu mg/l

The Contractor guarantees the following demineralized water plant performance (based

on the design input water):


Net throughput to service between regenerations

m3

Minimum net throughput to service

m3/day


- C1.7 -

C1.4 Start-up time guarantee

C1.4.1 Gas turbine start up (to be completed by Tenderer)

Operation on fuel gas Operation on fuel oil

Start up time (mins) Normal start

Fast start

Normal start

Fast start

Time from start to 100 % Gas turbine load

Time from start to 100% GT Block load

‘Start up’ is defined as beginning with all auxiliary plant shut down, and shall include any

preparation/purging time.

During the normal start up, the plant shall not be operated outside its normal operating envelope.

‘100% Gas turbine load’ is defined as Gas Turbine operating at maximum output.

‘100% GT Block load’ is defined as when the OCGT block (two gas turbines) reaches maximum output.

The Contractor shall submit start-up/shut-down curves for the above operating conditions.


- C1.8 -

C1.5 Guaranteed time for completion

The Contractor guarantees that the Works shall be complete and ready for Taking Over within a period of:

………. months (from Award of Contract)


- C2.1 -

SCHEDULE C2 MECHANICAL SCHEDULES

C2.1 Gas turbines

Item No


1. General information

1.1 Normal fuel

1.2 Standby fuel

1.3 Type of gas turbine

1.4 Model number

1.5 Manufacturer

1.6 Number of units

1.7 Mass of heaviest component for maintenance

tonnes

2. Compressor

2.1 Number of compressor stages

2.2 Compression pressure ratio

2.3 Blow-off valve (stage stages)

2.4 Variable angle blades (stage stages)

2.5 Rotor construction detail

3. Turbine

3.1 Number of turbine stages

3.2 Rotor construction details

4. Combustion chamber Fuel gas Fuel oil

4.1 Number, type and arrangement of combustion chambers

4.2 Number of flame nozzles

4.3 Burner type

4.4 Number of burners per chamber

4.5 Number and type of igniters

Document No. 62010/IPA/000001 Rev A 0654S132_SCHEDC2.DOC/S1/29/PMO

- C2.2 -

Item No


Fuel gas Fuel oil

4.6 Type of flame monitoring equipment

4.7 Number of flame monitors per chamber

4.8 Type of NOx reduction system

5. Bearings and seals

5.1 Number, type and location of bearings

5.2 Thrust bearing type/location

5.3 Type of compressor seals

5.4 Type of turbine seals

6. Turbine temperatures

6.1 Maximum metal temperature (each stage):

a. Moving blades

b. Fixed blades

6.2 Maximum cooling air flow

6.3 Method of injecting cooling air

7. Critical speeds and vibration

7.1 Operating speed rpm

7.2 Overspeed limit rpm

7.3 Gas turbine generator critical speeds:

a. Mode 1 torsional/lateral rpm

b. Mode 2 torsional/lateral rpm

c. Mode 3 torsional/lateral rpm

7.4 Operating/critical speed margin %

7.5 Vibration standard/level

8. Materials

8.1 Rotor shaft material

8.2 Compressor disc material

8.3 Turbine disc material


- C2.3 -

Item No


8.4 Compressor blades stage(s)

fixed

rotating

8.5 Compressor blade coating stage(s)

fixed

rotating

8.6 Turbine blading stage(s)

fixed

rotating

8.7 Turbine blading coating stage(s)

fixed

rotating

8.8 Combustion chamber:

a. Casing material

b. Lining method/material

8.9 Interconnecting crossfire tubes

8.10 Compressor casing

8.11 Turbine casing

8.12 Lubricating oil piping

8.13 Fuel piping:

a. Distillate fuel

b. Gas fuel

8.14 Insulation details

9. Couplings

9.1 Type

9.2 Rating


- C2.4 -

Item No


10. Blade cleaning

10.1 Injection system scope

10.2 Cleaning agent

10.3 Detergent tank capacity

10.4 Injection pump capacity/rating

10.5 Drain valve actuation type

10.6 Waste piping size/material

10.7 Waste water storage tank capacity m3

11. GT starting system

11.1 Type

11.2 Power rating kW

11.3 Type of drive interface unit

11.4 Max time from standstill to self-sustaining speed

sec

11.5 Number of permissible consecutive starts

12. GT barring and drive gear

12.1 GT barring/turning gear

a. Type

b. Turbine rotor barring speed rpm

c. Required duration after shutdown min

d. Inching facility

e. Manual barring facility

12.2 GT Auxiliary drive gear

a. Type

b. Manufacturer

c. Operating/rated power kW

d. Service factor (AGMA)

e. Input/output shaft speeds rpm


- C2.5 -

Item No


f. Mechanical efficiency %

13. GT Lubricating system

13.1 Grade of oil

13.2 Storage tank capacity m3

13.3 Retention time s

13.4 System capacity (refill) m3

Lubricating oil pumps Main Auxiliary Emergency

13.5 Number and capacity of pumps N x %

13.6 Drive type

13.7 Pump discharge conditions

a. Pressure bar a

b. Temperature °C

c. Flow rate kg/s

13.8 Absorbed power kW

14. Oil coolers

14.1 Type

14.2 Number and rating

14.3 Heat load kW

14.4 Lubricating oil temperature (inlet) °C

14.5 Lubricating oil temperature (outlet) °C

14.6 Cooling medium temperature (inlet) °C

14.7 Cooling medium temperature (outlet) °C

14.8 Cooling medium flow kg/s

15. Lub. oil Filters

15.1 Number and type of filter

15.2 Maximum capacity m3

15.3 Maximum pressure differential bar


- C2.6 -

Item No


15.4 Design pressure bar a

15.5 Degree of filtration microns

15.6 Filter element material

15.7 Method of cleaning filter

16. Lub oil Purifier

16.1 Type

16.2 Capacity m3/h

16.3 Temperature set point °C

Heater rating kW

17. Jacking oil system

17.1 Number and location of bearings with facility

17.2 Design pressure bar a

17.3 Number and type of pumps

17.4 Pump discharge conditions:

a. Pressure bar a

b. Temperature °C

c. Flow rate kg/s

17.5 Absorbed power kW

18. GT Air intake system

18.1 Manufacturer

18.2 Type of air filter

18.3 Material of filter medium

18.4 Design air flow m3/s

18.5 Maximum intake velocity m/s

18.6 Weather protection

18.7 Trash/bird screen

18.8 Number of filter modules


- C2.7 -

Item No


18.9 Number of filter elements per module

18.10 Differential pressure instrument type

18.11 Total pressure drop to compression inlet:

Clean/replace/trip mbar

18.12 Type of silencer

18.13 Material of silencer

18.14 Elevation of base of air inlet m

18.15 Access and lifting facilities

18.16 Filter operational life (guaranteed) hours

18.17 Pulse air supply system

18.18 Pulse air compressors

18.19 Compressor type

18.20 No. and rating N x %

18.21 Provision for air drying

18.22 Anti-icing system type

18.23 Dust removal system

19. GT Exhaust system

19.1 Ducting material

19.2 Thickness mm

19.3 Flow area m2

19.4 Gas velocity max/mean m/s /

19.5 Gas temperature, max °C

19.6 External or internal insulation

19.7 Cladding/insulation materials /

19.8 Cladding/insulation thickness’ mm/mm /

19.9 Method of attaching insulation

19.10 Max. external surface temperature °C


- C2.8 -

Item No


20. Expansion joints

20.1 Manufacturer

20.2 Type

20.3 Material:

a. Inner temperature shield

b. Outer cover

21. Exhaust Silencer

21.1 Type/location

21.2 Enclosure material

21.3 Enclosure material thickness

21.4 Heat insulation material/thickness mm

21.5 Acoustic material/thickness mm

21.6 Attenuator element material

GT Fuel Skids

22. GT fuel gas skid (one per GT)

22.1 GT Fuel gas filters

a. Type/material

b. Number and rating (per skid) N x %

c. Degree of filtration micron

22.2 Fuel gas flow meter

a. Type


c. Capacity Nm3/h

d. Accuracy %

22.3 Fuel gas stop/control valves

a. Number per skid

b. Type

c. Actuation


- C2.9 -

Item No


23. GT fuel oil skid (one per GT)

23.1 Fuel oil pumps

a. Type


c. Rated capacity m3/h

d. Discharge pressure bar

23.2 Fuel oil filters

a. Type/material


c. Degree of filtration micron

23.3 Fuel oil flow meter

a. Type


c. Capacity m3/h

d. Accuracy %

23.4 Fuel oil accumulators

Number and capacity

24. GT NOx water injection skid (if required)

24.1 NOx water injection pumps

c. Type

d. Number and rating (per skid) N x %

e. Rated capacity m3/h

f. Discharge pressure bar

24.2 NOx water filters

a. Type/material


c. Degree of filtration


- C2.10 -

Item No


24.3 NOx water flow meter

a. Type


c. Capacity m3/h

d. Accuracy %

25. GT ignition system

a. Ignition fuel type

b. System scope

26. GT fuel purge system

a. Purge system type

b. System scope


- C2.11 -

C2.2 GT exhaust stack/CEMS equipment

Item No


1. GT exhaust stack

1.1 Manufacturer

1.2 Design Code

1.3 Stack height m

1.4 Stack internal diameter m

1.5 Velocity at stack exit m/s

1.6 Min/max gas temperature for stack design (fuel oil)

°C

1.7 Min/max gas temperature for stack design (fuel gas)

°C

1.8 Stack material

1.9 Plate thickness mm

1.10 Corrosion allowance mm

1.11 Stack insulation

a. Location/type

b. Insulation material

c. Insulation thickness mm

d. Cladding/lining material

e. Cladding/lining thickness mm

2. Stack silencer

a. Type

b. Enclosure material/thickness mm

c. Heat insulation material/thickness mm

d. Acoustic material

e. Thickness of acoustic material mm

f. Attenuator element material


- C2.12 -

Item No


3. Continuous Emission monitoring (CEMS)

Manufacturer

Model/type

Probe/tapping point location

Flue gas temperature °C

Number analysers per GT/total

4. Probe/analyser details Type/model Manufacturer

Flue gas sampling probe

Flue gas SO2

Flue gas CO

Flue gas NOx

Flue gas O2

Flue gas moisture content

5. CEMS control equipment

Programming/operator workstation

a. Manufacturer

b. Model/processor

c. Communications

d. Serial data links to PCS

e. Serial data links (external)

6. Local panels (details of all panels)

a. Power requirements

b. Serial data links to PCS

7. PLC and microprocessor-based control system (specify and provide details of system)

a. Manufacturer

b. Model


- C2.13 -

C2.3 Fuel supply systems

C2.3.1 Fuel gas supply

Item No


1. Fuel gas supply system:

1.1 Design Code

1.2 System Design Flow Rate (DFR) (flow to two GTs)

kg/s

1.3 Piping design code

1.4 Below ground piping:

a. Pipe material

b. External protection

1.5 Above ground piping:

a. Pipe material


1.6 Allowable gas pressure range at supply TP (min/max)

bar a

1.7 System design pressure bar g

1.8 Allowable gas temperature range at supply TP (min/max)

°C

1.9 System Design Temperature °C

2. Emergency shutdown valve station:

2.1 No. of slam shut

2.2 Valve type and manufacturer

2.3 Actuator type and manufacturer

2.4 Size of valve mm

2.5 Time to close from receipt of signal

3. Fuel Gas Metering Station

3.1 Fiscal quality metering

3.2 No off meters

3.3 Type


- C2.14 -

Item No


3.4 Manufacturer

3.5 Capacity Nm3/s

3.6 Accuracy %

3.7 Turn down capability

3.8 Gas Chromatograph

a. Type/model

b. Accuracy %

c. Range

4. Separator/filter station Gas scrubbers Gas filters

4.1 Manufacturer

4.2 No off streams and rating N x %

4.3 Capacity Nm3/s

4.4 Separation efficiency: (% / particle size)

a. Solid particles % / µ

b. Aerosols/liquids % / µ

4.5 Pressure drop at design flow (clean/dirty) mbar

4.6 Flow turndown

4.7 Casing material

4.8 Filter material

5. Gas condensate tank

5.1 No. off

5.2 Capacity m3

5.3 Drain pump capacity m3/h

6. Gas dew point heating station (if required)

6.1 No off heaters and rating N x %

6.2 Type

6.3 Manufacturer


- C2.15 -

Item No


6.4 Capacity kg/s

6.5 Thermal input kW

6.6 Thermal efficiency of heater %

6.7 Gas inlet/outlet temperature °C

6.8 Type of control system

7. Gas compressor plant (if required)

7.1 Number off and rating N x %

7.2 Manufacturer

7.3 Type

7.4 Model number

7.5 Capacity Nm3/day

7.6 Discharge temperature °C

7.7 Discharge pressure bar(a)

7.8 Speed rpm

7.9 Critical speeds rpm

7.10 Compressor rating kW

7.11 Motor power requirement:

7.12 Minimum inlet pressure kW

7.13 Average inlet pressure kW

7.14 Maximum inlet pressure kW

7.15 Lubricated/non-lubricated

7.16 Cooling water system

8. Pressure regulating valve station

8.1 No off streams and rating N x %

8.2 Manufacturer

8.3 Valve type and manufacture

8.4 Actuator type and manufacture

8.5 Fuel gas inlet pressure (min/max.) bar a


- C2.16 -

Item No


8.6 Fuel gas inlet temperature (min. / max.) °C

8.7 Fuel gas outlet pressure (min.) bar a

8.8 Pressure drop bar

8.9 Size of valve mm

8.10 Method of control


- C2.17 -

C2.3.2 Fuel oil supply system

Item No


1. Fuel oil supply system:

1.1 Design Code

1.2 System Design Flow Rate (DFR) (flow to two GTs)

kg/s

1.3 Piping design code

1.4 Below ground piping:

a. Pipe material


1.5 Above ground piping:

a. Pipe material


1.6 Allowable pressure range at supply TP (min/max)

bar a

1.7 System design pressure bar g

1.8 Allowable temperature range at supply TP (min/max)

°C

1.9 System design temperature °C

2. Supply line metering/sampling station

a. Number of meters and rating

b. Meter type

c. Meter range

d. Accuracy

e. Sampler type


- C2.18 -

Item No


Fuel oil bulk storage tank

Fuel oil day tank

3. Fuel oil storage tanks

3.1 Manufacturer

3.2 Type of construction

3.3 Material

3.4 Number off

3.5 Design code

3.6 Internal diameter m

3.7 Height on straight m

3.8 Plate thickness:

a. Base mm

b. Shell mm

c. Roof mm

3.9 Corrosion allowance mm

3.10 Internal treatment

3.11 Capacity (nett) m3

3.12 Capacity (gross) m3

3.13 Weight of tank empty tonnes

3.14 Weight of tank full tonnes

3.15 Test pressure bar

3.16 Contents gauge

a. Make

b. Type

c. Range

3.17 Alarm indicators

a. Make

b. Type


- C2.19 -

Item No


Fuel oil bulk storage tank

Fuel oil day tank

4. Distillate fuel oil pumps

4.1 Number provided and rating N x %

4.2 Type

4.3 Manufacturer

4.4 Capacity l/s

4.5 Nett positive suction head at rated capacity m

4.6 Maximum power absorbed by pump kW

4.7 Discharge pressure at rated output bar

4.8 Speed rpm

4.9 Pump inlet connection diameter mm

4.10 Pump discharge connection diameter mm

4.11 Weight kg

4.12 Type of coupling

4.13 Casing material

4.14 Impeller material

4.15 Shaft material

4.16 Shaft sleeves material

4.17 Type of bearings

4.18 Pump control panel

a. Type

b. Make

c. Type of enclosure


- C2.20 -

Item No


Transfer pump suction

Forwarding pump suction

5. Strainers duty/service

5.1 Make

5.2 Type

5.3 Number off

5.4 Filtration level micron

5.5 Materials:

a. Strainer body

b. Strainer screen

6. Fuel treatment (if required)

6.1 Type

6.2 Manufacturer

6.3 Number of streams and % duty

6.4 Capacity per stream kg/s

6.5 Inlet condition:

a. Temperature °C

b. Water content %

c. Solids content %

d. Sodium and potassium content ppm

6.6 Outlet condition:

a. Maximum solids content ppm

b. Maximum particle size micron

c. Maximum sodium and potassium content

ppm

6.7 Power absorbed kW

6.8 Wash water:

a. Wash water quality

b. Wash water demand kg/s


- C2.21 -

Item No


6.9 Instrument air demand Nm3/h

7. Road tanker unloading station (if required)

7.1 Unloading/buffer tank

a. Tank capacity litres

b. Tank material

7.2 Unloading pumps

a. Number and % rating of pumps N x %

b. Capacity l/s

c. Drive rating kW

7.3 Filter station

a. Number off and rating N x %

b. Type

c. Capacity l/s

d. Filtration level

e. Changeover/cleaning method

f. Filter body material

g. Strainer material

7.4 Metering/sampling station

a. Number of meters and rating

b. Meter type

c. Meter range l/s


- C2.22 -

C2.4 Water supply and waste water systems

C2.4.1 Water demand

Item No


1. Raw water demand

1.1 Peak water demand (define) m3/h

1.2 System design flow rate m3/h

1.3 Basis of design flow

2. Service water demand




2.4 Demineralised water




2.8 Potable water





- C2.23 -

C2.4.2 Raw water treatment

Item No


1. Raw water treatment plant

1.1 Treatment type

1.2 Manufacturer

1.3 Number of streams and duty N x %

1.4 Net capacity m3/h

2. Design water analysis Raw water Service water

2.1 Neutral electricity conductivity micro ohms @ 20°C

2.2 Calculated TDS based on 0.60 ppm/microhm

2.3 pH

2.4 Free causticity as NaOH mg/kg

2.5 Total causticity as NaOH mg/kg

2.6 Equivalent mineral acidity as CaCO3 mg/kg

2.7 Total alkalinity as CaCO3 mg/kg

2.8 Total hardness as CaCO3 mg/kg

2.9 Calcium hardness as CaCO3 mg/kg

2.10 Magnesium hardness as CaCO3 mg/kg

2.11 Sodium as CaCO3 mg/kg

2.12 Potassium as CaCO3 mg/kg

2.13 Sulphate as CaCO3 mg/kg

2.14 Chloride as CaCO3 mg/kg

2.15 Nitrate as CaCO3 mg/kg

2.16 Iron as Fe mg/kg

2.17 Aluminium as Al mg/kg

2.18 Barium as Ba mg/kg

2.19 Ammonia as NH3 mg/kg

2.20 Permanganate value as KMnO4 mg/kg


- C2.24 -

Item No


2.21 Total organic carbon as C mg/kg

2.22 Reactive silica as SiO2 mg/kg

2.23 Non-reactive silica as SiO2 mg/kg

2.24 Suspended solids mg/kg

2.25 Detergents mg/kg

2.26 Phosphates as Na3PO4 mg/kg

2.27 Total ammoniacal nitrogen (free and saline) as NH3

mg/kg


- C2.25 -

C2.4.3 Demineralized water treatment plant

Item No


1. Demin. water treatment Plant

1.1 Treatment type

1.2 Manufacturer


1.4 Net capacity to service m3/h

1.5 Throughput rate m3/h

1.6 Design net output between regeneration m3

1.7 Service period between regeneration cycles h

1.8 Total waste water per regeneration m3

1.9 Waste water per m3 treated water to service m3/m3

1.10 Weight of 100% sulphuric acid for effluent neutralization per regeneration kg

1.11 Weight of 100% caustic soda for effluent neutralization per regeneration kg

1.12 Maximum flow rate to drain m3/h

1.13 Regenerant concentration (acid/caustic) %

1.14 Heaviest weight to be lifted

1.15 Air compressor capacity


- C2.26 -

C2.4.3.1 Demin water treatment plant - ion exchange units

As specified Item No Type of unit

Cation Anion Mixed bed

Alternatives

1. Number of units

2. Material

3. Thickness mm

4. Internal treatment

5. Thickness of internal treatment

mm

6. Diameter m

7. Height of straight m

8. Normal throughput/unit m3/h

9. Maximum throughput/unit m3/h

10. Maximum design pressure bar g

11. Net output/regeneration/unit m3

12. Volume of Ion Exchange Material

13. Cation m3

14. Anion m3

15. Freeboard m

16. Gross weight in operation (tonnes)

Approx

17. Regenerant/regeneration (100% H2SO4 100% NaOH)

kg

18. Regenerant concentration %

19. Weight of regenerant/volume of resin kg/m3

20. Exchange capacity of resin kg/m3

21. Capacity of unit per regeneration

kg CaCO3


- C2.27 -

C2.4.3.2 Demin water treatment plant - product water analysis

Item No Description Inlet water Outlet cation

Outlet anion

Outlet MB

1. Ph

2. Total cations (mg/l as CaCO3)

3. Alkalinity (mg/l as CaCO3)

4. EMA (mg/l as CaCO3)

5. Silica (mg/l as CaCO3)

6. Carbon dioxide (mg/l as CaCO3)

C2.4.3.3 Ion exchange material

Mixed Bed

Item No

Description Cation Anion Cation Anion

1. Name of Manufacturer

2. Place of Manufacturer

3. Manufacturer’s Code Name, Letter or Number

4. Life of Material (years)

5. Cost of Replacement Resin £ /m3

C2.4.3.4 Resin guarantees

(Resin is assumed to require replacement after 30 per cent loss of initial capacity).

% Reduction in replacement costs Item No Replacement after

Cation resin Anion resin

1. 1 year

2. 2 years

3. 3 years

4. 4 years

5. 5 years


- C2.28 -

C2.4.3.5 Activated carbon filters (if required)

Item No


1. Type of filter

2. Backwash sequence:

a. drain down for min

b. idle for min

c. air scour for min

d. idle for min

e. refill for min

f. backwash for min

3. Number of filters

4. Maximum throughput, per filter m3/h

5. Normal throughput, per filter m3/h


- C2.29 -


C2.4.4 Potable water treatment

Item No

Description

Particulars

1. Potable water treatment

1.1 Treatment type

1.2 Manufacturer


1.4 Net capacity to service m3/h

2. Design potable water analysis

2.1 Sodium (as Na)

2.2 Potassium (as K)

2.3 Calcium (as Ca)

2.4 Magnesium (as Mg) mg/kg

2.5 Chloride (as Cl) mg/kg

2.6 Sulphate (as SO4) mg/kg

2.7 Copper (as Cu) mg/kg

2.8 Iron (as Fe) mg/kg

2.9 TDS mg/kg

2.10 pH range mg/kg

mg/kg

- C

2.30 -

Docum

ent No. 62010/IP

A/000001 R

ev A

0654S132_S

CH

ED

C2.D

OC

/S2/3/P

MO

C2.4.5 Water supply system - storage tanks

Item No

Description Raw water (ifrequired)

Service/Fire water

Demineralized water

Potable water Chemical tanks (list)

1. Type of construction

2. Number off

3. Design code

4. Internal diameter m

5. Height on straight m

6. Capacity (net) m3

7. Capacity (gross) m3

8. Mass of tank (empty) kg

9. Mass of tank (full) kg

10. Design pressure bar(g)

11. Design temperature °C

12. Test pressure bar(g)

13. Test temperature °C

14. Material base/shell/roof

15. Plate thickness base/shell/roof mm

16. Painting/coating – internal/external

- C

2.31 -

Docum

ent No. 62010/IP

A/000001 R

ev A

0654S132_S

CH

ED

C2.D

OC

/S2/3/P

MO

C2.4.6 Water supply system – pumps

Item No

Description Raw water pumps

Service water pumps

Potable water pumps

Demin water forwarding

pumps

Chemical pumps (list)

Effluent mixing/

discharge pumps

Manufacturer

1.2 Type

1.3 Number off and per cent rating

1.4 Capacity l/s

1.5 Rated head bar

1.6 Duty power kW

1.7 Materials:

a. Impeller

b. Shaft

c. Shaft sleeves

d. Pump casing

e. Wearing rings

1.8 Suction strainer

1.9 Number off

1.10 Type

1.11 Manufacturer

1.12 Materials

- C2.32 -

Item no

Service

Piping design code

Material and grade

Internal coating/ lining

External coating/ painting

Pipe outside diameter

mm

Pipe wall thickness

mm

1. Raw water

a. below ground

b. above ground

2. Service water

a. below ground

b. above ground

3. Demineralized water

4. a. below ground

5. b. above ground

6. Potable water

a. below ground

b. above ground

7. Water treatment chemicals:

8. Acid regenerant

9. Caustic regenerant

10. Concentrated acid

11. Concentrated caustic

12. Other services

C2.4.7 Water supply system - pipework materials

Docum

ent No. 62010/IP

A/000001 R

ev A

0654S132_S

CH

ED

C2.D

OC

/S2/3/P

MO

- C2.33 -

C2.5 Closed circuit cooling water system

Item No


1. CCCW Pumps

1.1 Number of pumps and duty (eg 2 × 100%)

1.2 Normal flow of water for which each circulating water pump is designed m3/s

1.3 Corresponding power required to drive pump m3/s

1.4 Corresponding power taken by motor from source of supply kW

1.5 Speed rpm

1.6 Head generated at zero flow m

1.7 Type of bearings

1.8 Water temperature °C

1.9 Masses

1.10 Heaviest part of pump to be handled kg

1.11 Pump materials

a. Casings

b. Impellers

c. Shafts

d. Wear rings

2. Heat exchangers (fin/fan cooler)

2.1 Heat exchanger type/model

2.2 Design codes (thermal/structural)

2.3 Manufacturer

2.4 Number off per gas turbine and rating N x %

2.5 Number of fans per cooler pcs

2.6 No. of redundant fans per cooler pcs

2.7 Heat exchanger design ambient air temperature °C

2.8 Heat exchanger design heat load kW


- C2.34 -

Item No


2.9 Tube side fluid composition

2.10 Fluid inlet/outlet temperature °C

2.11 Tube side surface area m2

2.12 Excess tube side surface area for fouling %

2.13 Air inlet/outlet temperature °C

2.14 Air side surface m2

2.15 Excess air side surface area for fouling %

2.16 Sound power level dBA

2.17 Noise attenuation features

2.18 Tube material

2.19 Tube size (OD x thickness) mm

2.20 Tube pitch mm

2.21 Number of rows/passes

2.22 Fin material/coating

2.23 Fin pitch/thickness mm

2.24 Header material

2.25 Tube/header connection

2.26 Heat exchanger support frame material/protection

2.27 Fan Data

2.28 Number and rating per cooler N x %

2.29 Manufacturer

2.30 Type

2.31 Fan impeller/blade material

2.32 Blade angle adjustable

2.33 Fan drive

2.34 Belt tensioning

2.35 Air flowrate total Nm3/h


- C2.35 -

Item No


2.36 Air flow per fan Nm3/h

2.37 Motor

2.38 Manufacturer

2.39 Type

2.40 Rated motor power kW

2.41 Rated speed rpm

2.42 Total absorbed power (per cooler unit) kW

2.43 Rated voltage/frequency

3. CCW piping

3.1 Design code

3.2 Pipe material/grade


- C2.36 -


C2.6 Fire detection and protection

C2.6.1 General

Item No


General

1. Design codes/standards

2. All equipment FM/UL approved

3. Largest fire risk (identify)

4. Total water flow to feed largest risk area l/min

Fire pumps

5. Manufacturer

6. Type

7. Capacity l/mm

8. Pump developed head m

9. Number of electric driven pumps

10. Number of diesel driven pumps

11. Number of jockey pumps

12. Drive motor capacity kW

Water storage

13. Capacity of dedicated storage m3

14. Type of tank construction

Portable fire extinguishers

15. Number of dry powder type provided

16. Number of foam type provided

17. Number of carbon dioxide type provided

Fire alarm system

18. Manufacturer

19. Model

20. Number of fully equipped zones

Pipework

21. Size of ring main pipework for largest risk mm

22. System operating pressure barg

23. Spacing between external fire hydrants provided

m

- C

2.37 -

Docum

ent No. 62010/IP

A/000001 R

ev A

0654S132_S

CH

ED

C2.D

OC

/S4/2/P

MO

C2.6.2 Water/foam fire fighting systems

Item no.

Description Dimensionstaken

(m)

Envelopedareas

(m2)

Type ofdetector system wet/dry

Number of

detectors per unit

Number and type

of projectors

per unit

Minimum pressure at each

projector

(bar)

Discharge rate of

projector at

minimum pressure

(l/s)

Theoretical water

quantity per unit

(l/s)

Installation water

quantity per unit

(l/s)

1. Automatic high velocity water spray protection:

1.1 GT Generator transformer

1.2 Auxiliary transformer

1.3 Cable floors

1.4 Black start/emergency dieselgenerator

1.5 Others

2. Automatic wet pipe sprinkler:

2.1 Workshop and stores

2.2 Others

3. Automatic foam/water spray deluge:

3.1 Fuel oil pumphouse

3.2 Diesel engine fire pump

- C2.38 -

Item no.

Description Dimensionstaken

(m)

Envelopedareas

(m2)

Type ofdetector system wet/dry

Number of

detectors per unit

Number and type

of projectors

per unit

Minimum pressure at each

projector

(bar)

Discharge rate of

projector at

minimum pressure

(l/s)

Theoretical water

quantity per unit

(l/s)

Installation water

quantity per unit

(l/s)

4. Remote/manual water spray protection

4.1 Fuel oil storage tanks

5. Remote/manual foam injection system:

5.1 Fuel oil storage tanks

5.2 Others

6. Site fire hydrant system:

6.1 Site buildings and equipment

7. Hose reel protection

7.1 Administration building

7.2 Other buildings

Docum

ent No. 62010/IP

A/000001 R

ev A

0654S132_S

CH

ED

C2.D

OC

/S4/2/P

MO

- C2.39 -

C2.6.3 Foam injection equipment

Item No


1. Manufacturer

2. Overall size of skid m

3. Total weight of skid

4. Tank full/empty weight tonnetonne

5. Tank material

6. Pump capacity l/s

7. Minimum running water pressure required for operation bar

8. Type of foam

9. Foam concentrate pipework material

10. Foam application rate l/s

11. System duration at maximum rate of operation

mins

Contractor to give details of the fire protection system to be provided for the GT enclosures

C2.6.4 Operation

Item no


1. Normal pressure in water pipework bar

2. Pressure at which pressure maintaining device starts bar

3. Pressure at which first pump starts bar

4. Pressure at which second pump starts bar

5. Time delay between pumps sec


- C2.40 -

C2.6.5 Portable equipment

Item No


1. Capacity of dry powder extinguishers kg

2. Capacity of foam extinguishers litre

3. Capacity of carbon dioxide extinguishers kg

4. Capacity of water extinguishers litre

C2.6.6 Local and remote alarms facilities

Item No

Location No of local

audible fire

alarms

No of initiating

devices for remote fire

alarms

1. Automatic high velocity water spray system

2. Automatic medium velocity water spray system

3. Fire pumps

4. OCGT enclosures

5. Break glass units

6. Other alarms

Total


- C2.41 -

C2.7 Compressed air systems

Item No


Service air Instrument air

1. Compressed air design capacity m3/h

2. Basis of design (define)

3. Air compressors

3.1 Type

3.2 Number off/rating N x %

3.3 Capacity m3/s

3.4 Discharge temperature °C

3.5 Discharge pressure bar g

3.6 Compressor rating kW

3.7 Motor power requirement kW

3.8 Lubricated/non-lubricated

4. Air compressor motors

4.1 Type

4.2 Number off

4.3 Voltage V

4.4 Performance standard

4.5 Rated output kW

5. Aftercoolers

5.1 Type

5.2 Design

5.3 Cooling fluid

5.4 Heat load kW

6. Air receiver

6.1 Number off

6.2 Capacity/retention time m3/s


- C2.42 -

Item No


6.3 Design code

6.4 Design pressure bar(g)

6.5 Normal working pressure bar(g)

Com

pres

sor

inle

ts

Pre

-filte

r

Coa

lesc

ing

filte

r

Afte

r-fil

ter

7. Filters

7.1 Type/number off/rating %

7.2 Maximum capacity m3/h

7.3 Maximum differential pressure bar

7.4 Filtering efficiency/mesh size %/microns

7.5 Method of cleaning

8. Dryers

8.1 Manufacturer

8.2 Number and rating N × %

8.3 Type (eg Dessicant/refrigerant)

8.4 Design pressure bar(g)

8.5 Power consumption kW

8.6 Dew point temperature °C

9. Distribution piping

9.1 Instrument air main pipe size mm

9.2 Instrument air pipe material

9.3 Service air main pipe size mm

9.4 Service air pipe material


- C2.43 -

C2.8 Cranes (To be completed for each type of crane supplied)

Item No


1. Number of cranes provided

2. Location

3. Manufacturer

4. Type and classification to BS 466

5. Safe working loads:

a. Main hoist - slow speed tonne

b. Main hoist - fast speed tonne

c. Auxiliary hoist - slow speed tonne

d. Auxiliary hoist - fast speed tonne

6. Working speeds:

a. Hoist (creep speed/fast speed): m/min

b. Travelling (creep speed/fast speed) m/min

c. Traversing (creep speed/fast speed) m/min

d. Auxiliary hoist - fast m/min

7. Span (centre to centre of rails) m

8. Height of lift available m

9. Type of control

10. Power supply

11. Heaviest component to be lifted (eg turbine rotor)

Weight kg

Controller type/standard


- C2.44 -

C2.9 Cathodic protection plant - details of anodes and monitoring half cells

Item No Plant Anodes

No off

Length mm

Diametermm

Platinized length

mm

Design currentamps

Design current density Description

1. Fuel gas pipe

2. Fuel oil pipe

3. Raw water pipe

4. Service water pipe

5. Fire water pipe

6. Demin. water pipe

7. Potable water pipe

8. Effluent water pipe

9. Fuel oil tanks

10. Water storage tanks

11. Other


- C 3.1 -

SCHEDULE C3 ELECTRICAL SCHEDULES

C3.1 Generator

Item No

Description

Particulars

1. Apparent power (based on °C cold gas) MVA

2. Power factor (cos φ)

3. Power (Pn) MW

4. Voltage (Un) kV

5. Voltage regulation range +/- %

6. Current (In) kA

7. Frequency (Fn) Hz

8. Speed (Nn) r/min

9. Field current (Ifn) A

10. Field voltage (Ufn) V

11. Short circuit ratio (Kc)

12. Direct axis synchronous reactance (Xd) pu

13. Direct axis transient reactance unsaturated (X’di)

pu

14. Direct axis subtransient reactance unsaturated (X”di)

pu

15. Direct axis subtransient reactance saturated (X”dv)

pu

16. Negative phase sequence reactance at rated current (X2)

pu

17. Zero phase sequence reactance at rated current (Xo)

pu

18. Permissible negative phase sequence current

a. Continuous 12/IN pu

b. I2 2t sec

19. Direct axis short circuit transient time constant (T’d)

s


- C 3.2 -

Item No

Description

Particulars

20. Direct axis short circuit subtransient time constant (T”d)

s

21. Short circuit armature time constant (Ta) s

22. Direct axis open circuit transient time constant (T’do) s

23. Type of cooling

24. Method of cooling (direct/indirect):

Rotor winding

Stator winding

25. Type of insulation system

26. Thermal classification

27. Temperature rise:

Rotor winding K

Stator winding K

28. Temperature difference between cooled air/hydrogen and inlet cooling water with the generator operating at rated output K

29. Efficiency at rated power factor:

100% load %

75% load %

50% load %

25% load %


- C 3.3 -

C3.2 Excitation system

Item No

Description

Particulars

Requirements for excitation at operating temperatures

1. Response time for 2% step change in error signal S

2. Time for generator voltage to be restored within 2 per cent of nominal preset value following rejection of generator rated output s

Excitation transformer

3. Rated power kVA

4. Cooling method

5. Vector group

6. Rated current (secondary) A

7. Rated voltage (primary/secondary) V/V

8. Short circuit voltage %

Thyristor rectifier

9. Rated output voltage V

10. Rated output current A

11. Ceiling output voltage V

12. Ceiling output current A

13. Permitted duration of ceiling excitation s

14. Number of cooling fan units

15. Number of stand-by units

AVR

16. Type of AVR analogue/digital

17. Number of auto channels


- C 3.4 -

C3.3 Generator transformer

Item No

Description

Particulars

1. Manufacturer

2. Rated power MVA

3. Rated voltages

HV kV

LV kV

4. Vector group reference

5. Type of cooling

6. Maximum hot spot temperature rise above ambient at rated power

7. Impedance voltage at each end of tapping range at rated power %

8. Tappings

a. Size of steps as percentage of winding rated voltage %

b. Number of steps

9. Total mass of complete transformer tonnes

10. Overall dimensions m x m x m

11. Mass as arranged for transport tonnes

12. Dimensions as arranged for transport m x m x m

13. Quantity of oil l


- C 3.5 -

C3.4 Unit transformer

Item No

Description

Particulars

1. Manufacturer

2. Rated power MVA

3. Rated voltages

HV kV

LV kV


5. Type of cooling


7. Impedance voltage at rated voltage and power %

8. Tappings

Size of steps as percentage of winding rated voltage %

Number of steps




12. Dimensions arranged for transport m x m x m

13. Quantity of oil dB(A)


- C 3.6 -

C3.5 Auxiliary/emergency transformer (to be completed for each unit)

Item No

Description

Particulars

1. Manufacturer

2. Rated power MVA

3. Rated voltages

a. HV kV

b. LV kV


5. Type of cooling


7. Impedance voltage at rated voltage and power %

8. Tappings

a. Size of steps as percentage of winding rated voltage %

b. Number of steps




12. Dimensions arranged for transport m x m x m

13. Quantity of oil (if applicable) dB(A)


- C 3.7 -

C3.6 Main connections and neutral earthing equipment

Item No

Description

Particulars

MAIN CONNECTIONS

1. Manufacturer

2. Rated voltage kV

3. Rated insulation level kV

4. Rated normal current A

5. Rated short time withstand current kA

6. Rated peak withstand current kA

7. Nominal cross sectional area of conductors mm2

8. Temperature rise when carrying continuous maximum rated current K

NEUTRAL EARTHING

9. Manufacturer

10. Type

11. Fault rating kA

12. Resistor:

Resistance Ω

Fault rating/duration kA/sec


- C 3.8 -

C3.7 Generator switchgear

Item No

Description

Particulars

1. Manufacturer

2. Type

3. Rated voltage kV



6. Rated short circuit breaking current kA

7. Rated short circuit making current kA

8. Rated operating sequence

9. Mechanical performance

a. Opening time ms

b. Closing time at rated current ms

10. Weight of largest withdrawable unit kg

11. Overall dimensions L x H x D m x m x m

12. Overall weight kg

13. Dimensions of largest section for despatch L x H x D

m x m x m

14. Weight of largest section for despatch kg


- C 3.9 -

C3.8 MV switchgear

Item No

Description

Particulars

1. Manufacturer

2. Type

3. Rated voltage kV



6. Rated short circuit breaking current kA

7. Rated short circuit making current kA

8. Rated operating sequence

9. Mechanical performance

a. Opening time ms

b. Closing time at rated current ms



- C 3.10 -

C3.9 LV switchgear

Item No

Description

Particulars

1. Manufacturer

2. Type designation

3. Type

4. Rated voltage kV


6. 1 or 3 second short time current (as appropriate)

KA/sec

7. Fault rating kA

8. Operating duty



- C 3.11 -

C3.10 Black start/emergency diesel generator

Item No

Description

Particulars

Diesel engine

1. Manufacturer

2. Type

3. kW rating kW

4. Speed rev/min

5. Method of starting

6. Starting time on auto control sec

7. Capacity of fuel day tank l

Generator

8. Manufacturer

9. Rated power kVA/kW

10. Voltage V

11. Rated power factor cos φ

12. Frequency Hz

13. Weight of diesel generator complete kg

14. Dimensions of diesel generator m x m x m

15. Dimensions of fuel oil tank and support structure

m x m x m


- C 3.12 -

C3.11 Battery

Item No

Description

Particulars

1. Manufacturer

2. Type

3. Nominal voltage V

4. Number of cells for battery

5. Capacity of battery Ah

6. Voltage during float charge

Minimum V

Maximum V


- C 3.13 -

C3.12 MV motors (To be completed for each application)

Item No

Description

Particulars

1. Type of motor

2. Degree of protection

3. Cooling classification

4. Frame number

5. Class of insulation

6. Number of motors required for each generating set or for station

7. Voltage of supply V

8. Performance standard

9. Rated output kW

10. At rated output:-

Speed r/min

Efficiency %

Power factor

Line current A

11. Starting current at rated voltage A

12. Maximum permissible stalled time at rated voltage

s

13. Type of bearings

14. Manufacturer of motor


- C 3.14 -

C3.13 Cables (Proposed manufacturers catalogue information shall be provided for each the following types of cable)

Item No

Description

Particulars

1. MV cables

2. LV cables

3. Multicore cables

4. Telephone cables

5. High temperature cables

6. Mineral insulated cables

7. Thermocouple and compensating cables

8. Optical fibre cables

9. Coaxial cables

10. Network cables


- C 4.1 -

SCHEDULE C4 CONTROL AND INSTRUMENTATION SCHEDULES

C4.1 Control and instrumentation systems

Item No

Description

Particulars

PLANT CONTROL SYSTEM

1. General

1.1 Manufacturer

1.2 System type

1.3 Operating system software

1.4 Version

1.5 System availability MTBF/(MTBF + MTTR)

%

1.6 Give the configuration diagram which is specific to the tender and full technical details of:

a. Transmission media

b. Gateways/multiplexes/servers

c. Communications protocols

d. Data rates

1.7 Give full technical details of communications links to other computer systems

a. Hardware (modems, cabling)

b. Software (band rates, protocol, error connection etc)

1.8 Long term data storage (for each form of storage)

a. Selection criteria for storage medium

b. Manufacturer/Model No

c. Type/medium of storage

d. Capacity


- C 4.2 -

Item No

Description

Particulars

2. PCS configuration software packages

2.1 Give full technical details of all packages and licences supplied with the PCS.

3. PCS application software packages

3.1 Give full technical details of all packages and licences supplied with the PCS

3.2 Is all software guaranteed to be unaffected by date-related applications?

4. Response times

Give full technical details of the PCS response times

a. Time for change at input to display on Operator workstation

b. Time for change at operator workstation to output actuation

c. Resolution of time tagging of inputs

5. Display software

5.1 Number/ type of mimic diagrams

5.2 Number/ type of alarm displays

5.3 Number/ type of trend displays

5.4 Number of operation configurable displays

5.5 Number/type of reports

5.6 Number of operation configurable reports

6. Plant event management

6.1 Resolution of scan cycle

6.2 Resolution of time stamping

7. Sequence of events

7.1 Manufacturer/Type

7.2 Integrated with the PCS Yes/No

7.3 Resolution of time stamping ms

7.4 Resolution of scan cycle ms


- C 4.3 -

Item No

Description

Particulars

7.5 Storage capacity/medium

8. Operator workstations


8.2 No of workstations

8.3 No of monitors per workstation

8.4 Type of monitors

8.5 Type of cursor device

8.6 Type of keyboard

8.7 Size of usable screen mm x mm

8.8 Pixel resolution No. x No.

8.9 Operating system

8.10 Details of hardwire controls

9. Engineering workstations







9.7 Size of useable screen mm x mm



10. Diagnostic workstation

10.1 Manufacture/Type






- C 4.4 -

Item No

Description

Particulars


10.7 Size of useable screen mm × mm

10.8 Pixel resolution No × No


11. Printers

11.1 No of printers/types

11.2 Manufacturer

11.3 Printing technology

11.4 Resolution

11.5 Sound level dBA

12. Process stations

12.1 Number provided

12.2 Operating temperature range °C

12.3 Operating relative humidity range %

12.4 Degree of ingress protection (IP No) of cubicles

13. Estimated I/O count

13.1 Digital I/P

13.2 Digital O/P

13.3 Analogue I/P

13.4 Analogue O/P

14. Redundancy

14.1 Servers Yes/No

14.2 Data Networks Yes/No

14.3 I/O hardware Yes/No

14.4 Process Controllers Yes/No

14.5 Power Supplies Yes/No


- C 4.5 -

Item No

Description

Particulars

15. Station clock system


15.2 Number of clocks

16. List consumables to be supplied for two years operation


- C 4.6 -

Item No

Description

Particulars

CONTROL AND INSTRUMENTATION SYSTEMS

17. Gas turbine generator C&I package

17.1 Manufacturer/supplier

17.2 Control systems - type and redundancy

17.3 Protection systems - type and redundancy

17.4 Interfaces with PCS

a. Hardwired

b. Serial link (level of redundancy)

17.5 Vibration detection system

a. Manufacturer/Type

b. Detector types

17.6 Local operator interface

a. Manufacture/type

b. Type of monitor

c. Type of cursor device

d. Type of keyboard

e. Size of usable screen mm x mm

f. Pixel resolution No. x No.

g. Operating system

18. Generator C&I packages

18.1 Manufacturer/supplier

18.2 Control systems - type and redundancy

18.3 Protection systems - type and redundancy

18.4 Interfaces with PCS

a. Hardwired

b. Serial link (level of redundancy)

18.5 Vibration detection system

a. Manufacturer/Type


- C 4.7 -

Item No

Description

Particulars

b. Detector types

19. Electrical distribution system

19.1 Give full technical details of interfacing signals between distribution boards and PCS for

a. Gas turbine generator

b. Balance of plant

20. Gas analyser equipment

20.1 Manufacturer

20.2 Model

20.3 Analyser details

20.4 Type of interface to PCS

21. Fire detection equipment

21.1 Manufacturer

21.2 Model

21.3 Smoke detector type/model

21.4 Heat detector type/model


22. Gas detection equipment

22.1 Manufacturer

22.2 Model

22.3 Gas detector type/model

22.4 Number of gas detectors

22.5 Areas covered


23. Heating and ventilation system

23.1 Manufacturer

23.2 Model



- C 4.8 -

Item No

Description

Particulars

24. Black start diesel generators

24.1 Manufacturer

24.2 Model


25. Emergency diesel generators

25.1 Manufacturer

25.2 Model


26. Telephone system

26.1 Manufacturer

26.2 Model

26.3 Number of equipped extension lines

27. Closed circuit television

27.1 Manufacturer/type

27.2 Number of cameras and location

27.3 Number of monitors and location

27.4 Size of monitors

27.5 Storage device

28. Weather station

28.1 Manufacturer

28.2 Model

28.3 Parameters monitored and displayed on the PCS

a. Ambient temperature Yes/No

b. Humidity Yes/No

c. Wind speed Yes/No

d. Wind direction Yes/No

e. Barometric pressure Yes/No

f. Rainfall Yes/No


- C 4.9 -

Item No

Description

Particulars


29. Waste water discharge

29.1 Manufacturer

29.2 Model

29.3 Parameters monitored and displayed on the PCS

a. Waste water halogen residuals Yes/No

b. Waste water halogen residuals Yes/No


30. Service/Instrument air compressor system

30.1 Manufacturer

30.2 Model


31. Tariff metering instrumentation

31.1 Manufacturer

31.2 Model

31.3 Give details of the model and accuracy of

a. Exported and imported MWh and MWArh

b. Exported and imported MW and MWAr

c. Gas flow

Type of interfaces to PCS

32. PLC and microprocessor-based control systems (Specify and provide details of each system included)

32.1 Manufacturer/Model

32.2 Programming/operators workstation type

32.3 Data connection to PCS (description)

32.4 Redundancy

a. Processor

b. Communications


- C 4.10 -

Item No

Description

Particulars

c. Power supply

d. Data highway to PCS

33. UPS system


33.2 Guaranteed duration of supply Hours

33.3 Loads connected to supply under normal conditions

kVA

33.4 Nominal supply voltage of system V

33.5 Batteries Manufacturer/model

a. Number of cells per battery

b. Ampere hour capacity Ah

33.6 Battery charger Manufacturer/model

33.7 Static inverters Manufacturer/model

a. Number provided

b. Input voltage range V

c. Output voltage range V

d. Output frequency Hz


- C 4.11 -

Item No

Description

Particulars

CONDITION MONITORING SYSTEM

34. General


34.2 Provide a system description

34.3 Provide configuration diagram

34.4 Number and type of transducers

34.5 Interface with PCS

35. Software

35.1 Type

35.2 Version

36. Workstation type

36.1 No of monitors


36.3 Size of usable screen mm × mm


37. Printer

37.1 Printer type


37.3 Resolution



- C 4.12 -

Item No

Description

Particulars

PLANT PERFORMANCE MONITORING SYSTEM

38. General


38.2 Provide a system description

38.3 Provide configuration diagram

38.4 Interface with PCS

39. Software

39.1 Type

39.2 Version

40. Workstation type

40.1 No of monitors


40.3 Size of usable screen mm × mm


41. Printer

41.1 Printer type


41.3 Resolution



- C 4.13 -

Item No

Description

Particulars

PCS/CONTROL ROOM FURNITURE

42. Control desks

42.1 Manufacturer


42.3 Finish and material of working surfaces.

42.4 Area of free working surfaces

42.5 Method of mounting VDUs


42.7 Chairs

42.8 Manufacturer


42.10 Type of upholstery



- C5.1 -

SCHEDULE C5 CIVIL SCHEDULES

C5.1 HVAC systems

The Tenderer shall indicate below the design intent for all HVAC system proposed for this contract. The Tenderer shall also indicate any deviations from the specified systems and shall support this section by the submission of suitable catalogues to illustrate the quality of the equipment included.

Item No

Description

Particulars

1. Central chiller plant

1.1 Manufacturer

1.2 Chiller model

1.3 Number off (3 × 50%)

1.4 Capacity kW

2. Air handling units

2.1 Manufacturer

2.2 Capacity range m3/s

2.3 Number off

3. Axial fans

3.1 Manufacturer


3.3 Number off

4. Centrifugal fans

4.1 Manufacturer


4.3 Number off

5. Control systems

5.1 Manufacturer


- C5.2 -

C5.2 Details of buildings – structures and external finishes

The Tenderer shall describe fully below his proposals for foundations, structures and external finishes for every building.

Item No

Description

Particulars

1. Membrane (below ground)

1.1 Description

2. Structure

2.1 Piled foundation Type and size

2.2 Spread foundation

2.3 Steelwork superstructure

2.4 Concrete superstructure

3. External finishes

3.1 Wall cladding Type

3.2 Roof decking Type

3.3 Brickwork walls

3.4 Concrete roof

3.5 Waterproofing membrane (above ground)

3.6 Blockwork dado wall 2.4 m high

3.7 Render

3.8 Rough cast finish

3.9 Fair face concrete

3.10 Other

4. Building services

4.1 Potable water and domestic services

4.2 Building drainage

4.3 Lighting and small power


- C5.3 -

Item No

Description

Particulars

5. Doors , windows, etc

5.1 External doors – access Type

5.2 External doors – personnel Type

5.3 Internal doors Type

5.4 Windows Type

5.5 Louvres Type

6. Lightning protection

6.1 Please provide details

7. Tenderer shall provide a general description of the finish schedules of each building provided


- C5.4 -

C5.3 Superimposed loading for design

The Tenderer shall fully detail below the superimposed loads to be used for the design of all buildings and major areas within and around main buildings (including wheel axle loads for road design).

Building Area of building Superimposed loading for design kN/m2


- C5.5 -

C5.4 Site investigation

The Tenderer shall describe fully the site investigations he proposed to carry out prior to and/or during the design and construction of the Works.


- D1 -

SCHEDULE D SUPPLIERS OF MATERIALS, MANUFACTURERS, PLACES OF MANUFACTURE

TESTING AND INSPECTION

No Item Name of manufacturer

Place of manufacture

Place of test and

inspection

1. Gas turbine

1.1 Gas turbine/compressor

1.2 Gas turbine air inlet system

1.3 Gas turbine gearbox

1.4 Exhaust stack

1.5 Control equipment

2. Generator

2.1 Generator

2.2 Exciter system

2.3 Generator circuit breakers

2.4 Main connections

2.5 Generator neutral earthing equipment

2.6 Generator protection equipment

3. Fuel gas plant

3.1 Gas compressor

3.2 Filters

3.3 Coalescing filters

3.4 Pressure control valve

3.5 Heaters

3.6 Metering

3.7 Gas chromatograph

3.8 Gas receiver

3.9 Pipework

3.10 Cathodic protection

Document No. 62010/IPA/000001 Rev A 0654S140_SCHEDD.DOC/S1/5/PMO

- D2 -



Place of test and

inspection

4. Fuel oil plant

4.1 Tanks

4.2 Fuel treatment

4.3 Fuel oil pumps

4.4 Filters

4.5 Accumulators

4.6 Pipework

4.7 Metering


5. Compressed air system

5.1 Compressors

5.2 Dryers

5.3 Air receivers

5.4 Pipework


6. Fire protection

6.1 Fire water tank

6.2 Fire pumps

a. Motor driven

b. Engine driven

6.3 Detectors

6.4 Pipework

6.5 Foam system

6.6 Valves


7. Gas detection

7.1 Detectors



- D3 -



Place of test and

inspection

8. Closed cooling water equipment

8.1 Cooling water pumps

8.2 Heat exchangers (air blast)

8.3 Expansion tank

9. Water treatment plant

9.1 Process designer

9.2 Vessels

9.3 Pumps

9.4 Storage tanks


10. Heating, ventilation and air-conditioning plant

10.1 Chillers

10.2 Fans

11. Switchgear equipment

11.1 GIS switchgear

11.2 MV switchgear

11.3 LV switchgear

12. Motors

12.1 MV

12.2 LV

12.3 DC

13. Transformers

13.1 Generator transformer

13.2 Unit transformer

13.3 Station transformer

13.4 Excitation transformer

14. Battery equipment


- D4 -



Place of test and

inspection

14.1 Batteries

14.2 Chargers

14.3 Rectifiers

14.4 Instruments

15. Metering equipment

15.1 Integrating meters

15.2 Transducers

15.3 Selector relays

16. Cabling

16.1 Distribution boards

16.2 Power cables

a. HV

b. MV

c. LV

16.3 Multicore control cables

16.4 Telephone type cables

16.5 Fibre optic cables

17. Instrument transformer

17.1 Current transformers

17.2 Voltage transformers

18. Emergency and standby supplies

18.1 Emergency diesel generator

18.2 Standby diesel generator

19. Control, instrumentation and communications

19.1 PCS system software

19.2 VDUs

19.3 Printers


- D5 -



Place of test and

inspection

19.4 UPS

19.5 Telephone equipment

19.6 Public address equipment

20. Valves

20.1 Control valves

20.2 Valve actuators

21. CCTV

21.1 Cameras

22. Emission monitoring equipment

22.1 Analysers


23. Storage tanks

23.1 Service/fire water tank

23.1 Demineralisation water tank

23.2 Potable water tank


- E1 -

SCHEDULE E DRAWINGS AND DOCUMENTATION

E1 Drawings and documents included within the specification

To assist in preparation of the Tender, drawings have been prepared by the Engineer to illustrate the scope of the plant and interfaces with the existing power station systems and equipment ; these documents are contained in Volume 3 of this Specification.

In addition, a number of documents and reports which provide information on the site conditions and existing studies are included in Volume 4 of this Specification.

The Tenderer is advised that the above referenced documents and drawings are provided for information only and do not relieve the Tenderer of their obligation to fully assess the existing plant and provide functioning systems that comply with all requirements detailed in the Contract.

E2 Drawings and documents to be submitted with the tender

The Tenderer shall, as a minimum provide with his Tender the schedules fully completed in addition to the information and drawings as defined in the following list. The Tenderer shall submit with his proposal [5] complete sets of drawings, catalogues, etc. which shall serve to fully describe the scope of his Offer. These drawings shall include but not be limited to, general and dimensioned equipment arrangement drawings, narratives, sketches, material details, heat balance diagrams, process system flow diagrams, electrical one-line diagrams, power requirement diagrams, characteristic curves and any other details required to completely describe the proposal and enable evaluation by the Engineer.

The Tenderer may also support their proposal with manufacturer's catalogues where such catalogues illustrate operational features that cannot easily be depicted on drawings or narrative text. System descriptions should however be specific to the equipment offered and the wholesale use of generic catalogue information is not acceptable.

Item No Description

1. General documents (applicable to all plant)

1.1 Contract Management Documents (Refer also to Section 1 of the Specification)

a. Tender Programme

b. Quality/Inspection and Test Programme

c. Spares/special tool lists

d. Painting Specification

e. Reliability data and planned outage schedule

1.2 Plant operation and performance (distillate fuel and gas fuel)

a. OCGT plant operating philosophy

Document No. 62010/IPA/000001 Rev A 0654s150_SchedE.doc/S1/1/PMO

- E2 -

Item No Description

b. Heat and mass balance diagrams for the full range of operating cases

c. OCGT power output and efficiency correction curves.

d. OCGT power output and efficiency degradation curve vs operating hours (recovery after each overhaul shall be shown).

e. OCGT start up/shut down curves for hot, warm and cold starts, including cumulative fuel consumption and cumulative MWh generated/imported for each type of start and shutdown.

f. Emissions data (NOx and CO curves vs OCGT load and for OCGT start-up/shutdown, noise data etc.)

2. Mechanical plant and systems (Refer also to Volume 1, Section 6 of the Specification)

a. General Arrangement drawings, schematic diagrams (P&IDs), operating/performance data and descriptions of Gas Turbine and generator and auxiliary systems, including , air intake and exhaust, lub/jacking oil, fuel gas, fuel oil, NOx water, GT washing and drains, and GT cooling systems

b. Design concept, including schematic diagrams (P&IDs), operating/performance data and descriptions for auxiliary systems, including:

• Distillate fuel oil supply (unloading, storage, treatment and pumping)

• Fuel gas supply

• Emissions monitoring

• Cooling water system

• Water supply ; raw, service, potable and demin. water systems

• Water balance

• Sampling and dosing systems

• Waste water systems

• Fire detection and protection system

• Compressed air systems (Service and Instrument air)

• HVAC systems

c. Sizing calculations/criteria, operating/performance data & curves and arrangement drawings for auxiliary equipment, including :

• Potable and demineralized water treatment plant

• Fire water pumps, cooling water Pumps, fuel oil forwarding and NOx water pumps, Instrument air compressor, etc

• Heat exchangers : fin/fan coolers and CCW heat exchangers


- E3 -

Item No Description

• Tanks/vessels : design data for distillate fuel oil, raw/fire water, potable water and demineralized water storage tanks

• Valves : fuel gas pressure control

• Cranes/lifting equipment

3. Electrical Systems and Equipment (Refer also to Volume1, Section 7 of the Specification)

a. Single line diagrams

b. Schematics and technical information on. generator excitation and synchronization scheme.

c. Protection single line diagrams for main circuits.

d. Cabling concept .

e. Generator characteristic/capability curves and curves showing respective capabilities of turbine, generator and associated generator transformer over the specified CW/ambient temperature range.

f. Arrangement of generator internal cooling system.

g. Generator rotor withdrawal and insertion procedures and space required.

h. Descriptions of generator stator and rotor insulation systems and field lead assembly.

i. Descriptive technical information on generator switchgear and main connections including information to demonstrate suitability for application.

j. General arrangement of generator transformers.

k. Descriptive technical information on generator and other auxiliary transformers.

l. Descriptive technical information on essential supplies systems equipment.

m. Descriptive technical information on MV

n. Auxiliary load list including start up, operation and emergency shut down

o. Schedule of hazardous areas.

4. Control and Instrumentation (refer also to Volume 1, Section 8 of the Specification)

a. PCS Configuration concept/drawing

b. Control system protection concept

c. C&I cabling and earthing concept

d. Fire detection and alarm concept

e. Experience list for similar applications


- E4 -

Item No Description

f. Gas detection and alarm concept

g. Central control room layout drawing

h. Local control layout drawings

i. Gas turbine controller descriptions

5. Civil/Buildings (refer also to Volume 1, Section 9 of the Specification)

a. Site layout, showing the position of all buildings and major plant items

b. Contractors proposed laydown/working areas and site establishment

c. Architectural Concept Statement

d. Architectural elevations, sections and general arrangement of the site and main buildings.

e. Preliminary piling and foundation concept

f. Design basis statement for building services and site services

g. Civil and structural general arrangement drawings, including all major plant items of:

• Gas turbine area, including transformers and auxiliary plant

• Fuel gas supply system, including AGI and compressor station

• Fuel oil supply system, including fuel oil unloading, storage tank, treatment and pumping areas

• Cooling water system, including fin/fan coolers

• Water supply system, including WTP building area and raw, potable and demineralized water storage and pumping areas

• Waste water drainage system

• Service routing concept, including pipe and cables

h. Any other submissions required by Volume 1, Section 9 of the Specification.

E3 Drawings and documents to be submitted during the contract

E3.1 General requirements

Drawings and information shall be submitted in accordance with Section 4 of the Specification and the requirements as defined below.

All drawings shall be to scale and fully detailed. All important dimensions shall be given and the material of which each principal part is to be constructed shall be indicated. Drawings shall not exceed A0 standard dimensions and shall bear approved contract references.


- E5 -

E3.2 Control

For all work to be performed under the Contract, the Contractor shall establish and maintain a comprehensive computer based document control system ensuring that the identification, revision, status and location, at all phases of the Work, can be determined. The Contractor’s system shall include all sub-contractors’ and vendors’ documents.

E3.3 Organization of documentation

All documentation shall be organized in a logical manner and all contents shall be properly indexed. A revision status record sheet at the front of each document shall facilitate recording of amendments in a logical manner. All changes shall be clearly marked on the new revised drawings. Revision indication and issue dates shall also appear on each amended sheet. The cover shall identify the contents.

E3.4 Quality

Documentation shall be suitable for long term storage.

E4 Extent of drawings and documents to be submitted for approval/review and for information

The Contractor shall submit to the Engineer a detailed schedule and programme detailing all drawings and documents that will be submitted for approval and or review and for information to the Engineer, based on the list as given in the table below. This list will include all schematic diagrams, general arrangement drawings, terminal point drawings, foundation drawings and electrical single line diagrams necessary to give a full understanding of the equipment offered and demonstrate full Contract compliance.

The drawing/document submission schedule shall be maintained and issued monthly by the Contractor with the Progress Report.

Copies of each drawing, calculation and data sheet shall be submitted in accordance with the submission programme and distribution list included later in this section .

As a minimum, the following documents and drawings shall be submitted to the Engineer for approval:

a. Contract Programme (first issue) – thereafter for review

b. Inspection and Test Programme

c. Performance Test Procedures

d. Process schematics, P&IDs and system descriptions

e. Site layout drawings and arrangement drawings for main plant

f. Plant Performance Test Procedure and Records.

No drawing will be accepted by the Engineer unless it is stamped or marked as checked and approved by the Contractor.


- E6 -

The Owner may at their discretion request additional drawings where the Contractor has provided insufficient information to assess any item of plant or equipment. As a minimum the Contractor shall provide the following drawings:

Item No Description

1 General documents (applicable to all plant)

1.1 Contract Management Documents (refer also to Volume 1, Section 1 of the Specification)

a. Contract Programme

b. Quality/Inspection and Test Programme

c. Quality Plans

d. Inspection and testing procedures/reports

e. Spares lists - Major/strategic spares list and recommended spare parts/consumables lists

f. Special tools list

g. Plant referencing and labelling details

h. Painting Specification

i. List of applicable Codes and Standards

j. Hazardous area classification drawings

k. Hazid/hazan/hazop studies and reports

l. Terminal point schedules and drawings

m. Certification of pressure systems and lifting equipment

n. Site testing, commissioning procedures and records

o. Preventative maintenance schedules

p. Operating and maintenance manuals

q. As-built/record copy drawings and documents

1.2 Plant operation/performance (distillate fuel and gas fuel)

a. Performance Test Procedure and Test Records

b. Heat and mass balance diagrams for the full range of operating cases

c. Auxiliary power listing

d. OCGT power output and efficiency correction curves.

e. OCGT power output and efficiency degradation curve vs operating hours


- E7 -

Item No Description

(recovery after each overhaul shall be shown).

f. OCGT start up/shut down curves for hot, warm and cold starts. These must include cumulative fuel consumption and cumulative MWh generated/imported for each type of start and shutdown.

g. NOx and CO curves -vs- OCGT load

h. NOx and CO curves during each type of OCGT start-up/shutdown.

i. Noise data and test procedure

2 OCGT plant and systems (refer also to Volume 1, Section 6 of the Specification)

2.1 Gas turbine

a. Technical specification and description of GT and auxiliary systems,

b. General arrangement drawings and sections of main equipment and auxiliary systems, including fuel oil/gas and NOx water blocks

c. Schematic diagrams (P&IDs),descriptions and data for GT systems (fuel oil/gas supply, air/gas, lub. oil, drains etc.)

2.4 General mechanical

a. Equipment list

b. Valve list

c. Termination point schedules and drawings

d. Pipework schedules and layouts

2.5 Auxiliary systems and equipment:

System descriptions and diagrams (P&IDs), terminal point schedules and drawings, operating/performance data and arrangement drawings for the following systems and equipment:

a. Fuel gas supply system, including treatment, metering and pressure control equipment

b. Fuel oil supply (unloading, storage, treatment and pumping), including storage tank data and drawings, fuel oil treatment equipment data and drawings, fuel oil pump station data and drawings, and fuel oil drainage system concept.

c. Water supply system (potable, service and demineralized water ), including water balance, interfaces and arrangement of water treatment plant, raw, potable and demin. water storage tank data and drawings, NOx water transfer pump station data and arrangement drawings.

d. Closed cooling (CCCW) system fin/fan heat exchanger data and drawings, circulating pump curves and drawings.

e. Waste water system, including emissions monitoring concept.


- E8 -

Item No Description

f. Sampling systems data, equipment specifications and drawings

g. Emission monitoring system data, equipment specifications and drawings

h. Fire detection and protection system data, equipment specifications and drawings

i. Service air system data, equipment specifications and drawings, including interfaces with the existing systems

j. Instrument air system, including compressor operating/performance data and arrangement

k. HVAC system data, equipment specifications and drawings, including interfaces with the existing systems

l. Cranes and Lifting equipment, including crane

3 Electrical systems and equipment (refer also to Volume 2, Section 3 of the Specification)

a. General arrangement and sections for generator and exciter.

b. Protection diagram for complete installation, general arrangement of equipment.

c. Generator excitation schematic diagrams, general arrangement of equipment and interfaces with plant control system. .

d. Characteristic and capability curves for generator.

e. Capability curves for transformers.

f. General arrangement of generator switchgear.

g. General arrangement of generator transformer and auxiliary transformers.

h. General arrangement of MV and LV switchboards.

i. Descriptive technical information on protective relays.

j. Single line diagrams for all ac and dc systems, and protection single line diagrams for all main circuits.

k. Schedule of electrical equipment for hazardous areas.

l. Schematic diagram of synchronizing scheme.

m. Design, calculations, schedules and drawings, including connection and termination drawings of the cabling system..

n. Design, calculations and drawings of the earthing and lightning protection systems.

o. Short circuit and voltage drop calculations.

p. Calculations to confirm nominal ratio and tapping range of transformers.


- E9 -

Item No Description

q. Insulation co-ordination study.

r. Phasing diagram including transformer vector groups.

s. Instrument transformer calculations.

t. Control and interlocking logic for MV and LV switchgear.

u. Protective relaying co-ordination.

v. Design, calculations and drawings of lighting and small power installations.

w. Operating and maintenance instructions for all electrical equipment.

4 C&I systems (refer also to Volume 1, Section 8 of the Specification)

a. Design and operation philosophy

b. Functional design specification

c. Graphics functional design specification

d. Alarm philosophy

e. Tripping/shutdown philosophy

f. PCS description and configured logic diagrams.

g. GT governor and load control description and logic diagrams.

h. AVR and PSS description, block control diagram.

i. PCS thermodynamic model.

j. Details of plant conditioning monitoring system.

k. Aqueous and gaseous emission monitoring philosophy and equipment details.

l. Technical descriptions and data sheets

m. Gas detection system data, equipment specifications and drawings

n. Instrument data sheets

o. Instrument schedule

p. Alarm schedule (including data logging/information inputs) and alarm management philosophy

q. Input/output schedule (including serial data)

r. General arrangement drawings

s. Equipment layout drawings

t. Installation drawings


- E10 -

Item No Description

u. Wiring diagrams and schematics

v. Cable connection/termination drawings

w. Interface diagrams

x. Software listings

y. Commissioning procedures

z. Functional test procedures

aa. Performance test procedures

bb. Hardware test specification

cc. Software test specification

dd. Factory acceptance test procedures

4.1 Microprocessor based systems

a. Operation and control philosophy

b. Control and protection system details

c. Menu guide to control system facilities

d. Description of all sequences in a structured step-by-step format

e. Printed error message guide

f. Alarm message guide

g. Brief description of any hardware back-up features

h. Process parameter values under normal operating regimes

i. Hardware trouble-shooting guide

j. Instructions for changeover from remote to local control and vice-versa

k. Plant configuration and database listing

l. Plant operating system listing

m. User-configurable software listing

n. System error messages listing

o. Trouble-shooting guidelines

p. On and off-line diagnostic software

q. Communications network management software


- E11 -

Item No Description

r. Hardware list and system diagrams

s. Start-up instructions for all hardware

t. Listing of system error messages

u. Description of links or interface hardware between vendor control packages and PCS

v. I/O card listing identifying location and function

5 Plant layout/Civil (refer also to Volume 1, Section 9 of the Specification)

a. Site layout drawings, showing the position of all buildings and major plant items

b. Contractors proposed laydown/working areas and site establishment

c. Civil and structural design basis statements

d. Detailed design and construction programme

e. Site investigation proposals and reports

f. Setting out station details

g. Working drawings and all supporting calculations for all buildings and structures, including:

• Gas turbine foundations including analysis for dynamic effects

• Stack superstructure and foundations

• Transformer foundations

• Ancillary buildings superstructure and foundations

• Road layout and details

• Drainage systems and outfalls

• Building permit approvals

• Method statements for items of construction (submitted to Site Management Team)

Notwithstanding the above all other drawings and documents shall be submitted to the

Engineer for information.

E5 Document submission programme

The following list is intended to summarize the key dates when documents are to be submitted under the Contract. The list is not exhaustive and does not prevent the Engineer from requesting additional documents as and when required.


- E12 -

It is the responsibility of the Contractor to prepare and maintain a detailed schedule covering all document and drawing submissions throughout the Contract, based on the outline requirements as stated in Volume 1 of the specification, and as defined below :

Document description Submission period

Contract Programme Within 30 days of Letter of Acceptance. Thereafter monthly no later than 1 week from effective date

Design Schedule Within 30 days of Letter of Acceptance. To be integrated into the Contract Programme

Drawings and Document Submission Schedule

Within 30 days of Letter of Acceptance. To be integrated into the Contract Programme

Procurement and Manufacturing Schedule Within 30 days of Letter of Acceptance. To be integrated into the Contract Programme

Construction Schedule and Resource Schedule

Within 60 days of Letter of Acceptance. To be integrated into the Contract Programme

Commissioning Schedule 12 months prior to the start of any commissioning activities to be approved no later than 6 months before the start of any commissioning activities. To be integrated into the Contract Programme

Performance Test Procedure 6 months prior to programme test date (final form)

Progress Reports Monthly

Quality Assurance

Project Quality Plan Within 30 days of Letter of Acceptance

Works inspection and Test Records In accordance with Quality Plan

Site inspection and Test Records In accordance with Quality Plan

Method Statements for Construction In accordance with Construction Schedule

Developed Health & Safety Plan 60 days prior to commencing work on site

Formal Performance Test Procedure and Records

6 months prior to commencement of testing

Design Information

Design Calculations In accordance with Document Submission Schedule and Design Schedule

Drawings for review In accordance with Document Submission Schedule and Design Schedule

‘As Built’ Drawings Within 60 days of take-over date


- E13 -

Document description Submission period

Sub contract information

Purchase Orders Within 7 days of Purchase Order issue

Operation and Maintenance Manuals

Draft Operation and Maintenance Manuals 6 months prior to commencement of commissioning

Final Operation and Maintenance Manuals 4 months after Taking Over certificate

E6 Document distribution

All documents, drawing, etc. shall be submitted and distributed as shown hereunder. The table indicates number of copies. In addition one transparency and one electronic copy of all documents shall be submitted via the project information and control system to Engineer’s head office and Owner’s head office.

Head Office Site Office Total Documents

Owner Eng Owner Eng

Contract Monthly Progress Report 2 2 1

Site weekly progress report 2 2

Site daily progress report 2 2

Contract Programme 2 2 1

Commissioning Schedule 2 2 1

Performance Test Procedure 2 2 1

Quality Assurance :

Project Quality Plan (Inspection & Test plan)

2 2 1

Inspection & test Procedures (welding, NDE, works test etc)

2 2 1

Works inspection and Test Records 2 2 1

Site inspection and Test Records 2 2 1

Method Statements for Construction 2 1

Construction & Design & Management Rules

2 2 1

Developed Health & Safety Plan 2 2 1


- E14 -

Head Office Site Office Total Documents

Owner Eng Owner Eng

Formal Performance Test Procedure and Records

2 2 1

Test Certificates/test reports 2 2 1

Design Documents/Drawings : 2 2 1

Design Calculations 2 3 1

Docs/Drawings for review/approval 2 3 1

Docs/Drawings for information 2 2 1

‘As Built’ Drawings 2 2 1

Purchase Orders/Sub-orders 1 2 1

Shipping documents (per contract general conditions)

1 1 1

O&M Manuals :

Draft O&M manuals 3 4 2

Final O&M manuals 6 1 1

Other Documents :

Miscellaneous documents 2 2 1

Codes and standards (alternative code)

2 2 1

Original codes and standards 2 1 1

Note: 1) In addition to the above indicated submittals and distribution of drawings, the Contractor shall submit to the Engineer the documents as stipulated in the Volume 1 of this Specification.

2) Where possible, electronic copies of documents to be submitted at the same time as the hard copies. Unless specified otherwise, electronic files shall be compatible with Microsoft office programmes.

3) O&M manuals complete with drawings to be submitted in electronic format.


- F1 -

SCHEDULE F VARIATIONS FROM SPECIFICATION

(to be completed by the Tenderer as applicable)

Notes :

1. Unless a specific Variations detailed in this Schedule F, the Tenderer shall be deemed to comply fully with the requirements of the Specification.

2. The Tenderer shall use the Clarification/Deviation format included on the CD ROM which is enclosed with the Enquiry Specification.

3. Each Clarification or Deviation shall be uniquely numbered using the Ref. No. in Column A of the sheet.

4. Each Clarification or Deviation shall refer to the Volume/Section and Page of the Enquiry Specification, and include a relevant extract from the Enquiry Specification.

Specification / Ref.

Specification Requirement Ty

pe

Tenderer Comment Ref

No. Vol. Section Page C/D

001

002

003

004

005

006

007

008

009

010

011

012

013

014

015

016

017

018

019

020

Document No. 62010/IPA/000001 Rev A 0654S160_SCHEDF.DOC/S1/1/PMO

- G1 -

SCHEDULE G TESTS AND INSPECTIONS

G1 GENERAL TESTS AND INSPECTIONS

G1.1 General requirements

Tests and inspections shall include electrical, mechanical, hydraulic or any other tests to ensure that the plant being supplied complies with the requirements of the Specification and with the standards as applicable to the plant.

Tests shall be conducted in accordance with the specified standards. For equipment not covered by such test standards nor specifically mentioned in the specification, the test procedure shall be agreed between the Engineer and the Contractor.

All important forgings are to be jointly examined at the manufacturer’s factory by the Engineer and by representatives of the manufacturer during forging and heat treatment.

An approved method of radiographic or other non-destructive testing is to be used for proving all welding associated with pressure vessels. The Contractor shall supply suitable test pieces of all materials as required by the Engineer.

Control, instrumentation and plant control system will be subject to Factory Acceptance Tests (FAT), which will be carried out at the Contractor’s works. These tests will be carried out after the Contractor has completed all his integrated system testing in the Works and consists of General System Testing and Performance Testing.

In addition to particular inspections and tests specified herein, the Engineer reserves the right to carry out any such other inspections and tests as he may deem necessary to ensure that the works complies with the requirements of the specification.

G1.2 Materials

All materials must be supplied in accordance with the EN Group of Standards and Specifications or equivalent with written agreement of the Engineer. The Contractor shall indicate the generic material type(s) being processed ie 1 per cent Cr steel, 2¼ per cent Cr. steel, 9 per cent Cr. steel, stainless steel, etc, and the nature of the work, ie forging, casting, fabrication work, etc.

The Contractor shall provide test pieces as required by the Engineer to enable him to confirm the quality of the material supplied under the Contract. Such test pieces shall be prepared and supplied free of charge and any cost of the tests shall be borne by the Contractor.

If any test piece fails to comply with the requirements of the appropriate specifications for the material in question, the Engineer may reject the whole of the material represented by that test piece; the Contractor’s or subcontractor’s designers and metallurgists will be consulted before any material is so rejected.

Document No. 62010/IPA/000001 Rev A 0654S170_SchedG.doc/S1/17/PMO

- G2 -

If the Engineer is furnished with certified particulars of tests which have been carried out for the Contractor by the suppliers of material, he may, at his own discretion, dispense with the previously mentioned tests.

G1.3 Castings

Castings where defined below for specific components or equipment shall be examined by Magnetic Testing (or penetrant testing for non-magnetic castings) and Ultrasonic Testing using established procedures and acceptance standards which have been approved by the contractor and submitted.

Weld repairs may be made at the foundry prior to final heat treatment without the permission of the Engineer but records and maps showing the excavation sizes and defect types shall be submitted prior to commencement of repairs. Major repairs are defined as excavations >20 per cent of the wall thickness or >25 mm deep, or >65 cm2, or which result in leakage on hydrostatic test. All other repairs are classed as minor repairs.

Major weld repairs shall not be made after rough machining without the prior written agreement of the Engineer. Requests to repair after rough machining shall be accompanied by the weld repair procedure, the supporting procedure qualification report and a map indicating the defect types and the dimensions of the excavations. Minor repairs after rough machining shall be reported to the Engineer.

G1.4 Forgings

Forgings shall be supplied in compliance with the applicable standards and specifications except where modified elsewhere in this document.

Forgings as defined below for specific components or equipment shall be examined by ultrasonic testing after rough machining. Bores, fillets and changes of section shall be examined by magnetic testing (penetrant testing for non-magnetic materials).

G1.5 Welding

All fabrication welding and, where agreed in writing by the Engineer, repair welding must be carried out using written and qualified procedures, welders and operators except where modified and agreed in writing with the Engineer.

At least 8 weeks prior to commencing fabrication the Contractor shall, except where otherwise agreed by the Engineer, submit for review four copies in the English language of:

• Welding procedures together with the relevant procedure qualification records.

• Non destructive testing procedures.

• Heat treatment procedures.

Welding procedures and welders' qualifications shall be in accordance with the latest revision of BS EN 288 and BS EN 287 respectively or equivalent ASME Standards.


- G3 -

The welding procedures submitted shall include all of the details required by BS EN 288, both essential and non-essential variables for the particular welding process(es) together with a detailed sketch of the weld joint.

The Contractor shall maintain for review, or if requested shall submit to the Engineer documentary evidence of the competency of all welders employed on the Contract. Where documentary evidence does not exist welders' qualification tests will be required by the Engineer. If in the opinion of the Engineer the welders are not carrying out the work in a suitable manner the Engineer reserves the right to call for samples of welding for examination and test. The Contractor shall bear all costs for carrying out such tests.

For the purposes of identification, the welders name and/or check number shall be retained by the Contractor as part of the Quality Assurance System. These documents shall be made available for review by the Engineer.

In no case whatsoever will stamping or hammering of alloy material be allowed.

Welding consumables eg electrodes, filler wires, flux and shielding gas shall deposit weld metal that has mechanical properties at least equal to the minimum values required for the parent material.

All consumables shall deposit weld metal of similar composition as used in the procedure and welders' qualification tests.

The Contractors welding plant and ancillary equipment shall be in accordance with the appropriate parts of EN 60974 and shall be maintained in good working order.

Permanent backing rings are not permitted and temporary backing rings shall only be used as allowed by the relevant approved welding procedure.

All surfaces for welding shall be clean and free from paint, oil, grease, rust, scale or other material detrimental to welding. All butt weld preparations shall be completed by machining, grinding, machine or manual flame cutting with subsequent grinding.

The use of temporary attachments welded to components shall be avoided where possible. If used, the attachments shall be removed flush with the base metal after they have served their purpose and the area of attachment shall be examined by the method specified for permanent fillet welds in the system.

The carbon contents shall not exceed 0.25 per cent for carbon and carbon-manganese steels which are to be welded unless otherwise approved in writing by the Engineer.

Where post weld heat treatment is required by the fabrication specification the heat treatment charts showing temperature time shall be retained by the Contractor. The charts shall indicate the heating and cooling rates, holding temperature and time and shall clearly identify the component(s) or weld(s) heat treated.


- G4 -

Sufficient thermocouples shall be in contact with the furnace load to ensure adequate heat treatment. Attachment shall be by capacitor discharge method unless otherwise agreed by the Engineer.

Welding in the fabrication shop or at Site shall be done under the supervision of a qualified welding engineer.

G1.6 Non-destructive testing

NDT of castings, wrought products and weldments shall be carried out in accordance with the appropriate Euro Norme except where otherwise specified by the Engineer.

The techniques of ultrasonic, radiographic, magnetic particle, liquid penetrant and leak detection methods applicable to all the principle items of plant shall be to the approval of the Engineer.

Dye penetrant examination shall not be used on ferritic materials.

NDT operators shall be qualified in accordance with an agreed nationally accredited scheme such as the Personnel Certification in Non-destructive testing (PCN) scheme and shall be certificated to level II or higher of that system. Alternative NDT qualifications equivalent to NDT level II may be submitted to the Engineer for approval. Where in-house qualification systems are employed these will be subject to quality audit by the Engineer.

The Contractor shall submit a document relating the weld procedure, weld finish, acceptable criteria and the extent and method of non-destructive testing for each weld or group of welds.

The Contractor shall institute and maintain a record of all approved non-destructive tests and these records shall be readily available for verification by the Engineer.

Where requested the welding, heat treatment and manufacturing procedures shall be submitted.

G2 TESTS IN MANUFACTURER’S WORKS

G2.1 Tests on mechanical systems and equipment

G2.1.1 General

The tests shall be arranged to represent working conditions as closely as possible.

Type tests when called for shall be made on equipment which has previously passed its routine tests.

Where type tests have been carried out under previous contracts on equipment similar in all essential respects to the equipment included in the Contract, the Engineer may waive the type tests on production of complete test records relating to the equipment concerned.


- G5 -

G2.1.2 Gas turbines and auxiliary equipment

Each gas turbine shall be tested separately at the manufacturer’s works in accordance with the manufacturer’s standard test procedures. The tests shall be carried out to ensure smooth and satisfactory operating of the unit.

Detailed test procedures shall be submitted by the Contractor and shall be subject to the Owner’s approval.

Insulation tests shall be carried out on all control panels. Prior to test, electronic instruments and similar items shall be isolated to prevent damage. The insulation resistance of the remainder of the equipment shall be measured at a minimum of 500 V during manufacture. After reconnection of all equipment the circuits shall be checked.

Function/sequence tests shall be carried out which simulate as far as practicable the performance of the turbines. These shall include all automatic sequencing, protective gear and alarms.

G2.1.3 Pipework

The supply, fabrication and erection of all pipework shall comply with the requirements of EN 13480 or ANSI B31.1.

All butt welds shall be full penetration welds with complete fusion between weld runs and base metal.

The following tests shall be carried out on welds (both shop and Site).

a. 100 per cent visual examination of all welds to the requirements of the application standard.

b. At least 10 per cent ultrasonic or radiographic and surface flow examination on all pipe butt welds and branch welds to the acceptance criteria of the applicable standard.

c. At least 10 per cent magnetic particle examination of all fillet welds.

d. Hydrostatic test to the requirements of the applicable code.

Weld defect acceptance levels shall be in accordance with the applicable standard except that lack of root fusion or incomplete root penetrant will not be permitted.

G2.1.4 Structural steelwork

Welding and inspection in both shop and site shall be in accordance with Section 5 of BCSA publication No 203/93 - National Structural Steelwork Specification for Building Construction, or AWS D1.1 except as modified by Section 9 of the Contract Specification.


- G6 -

Where only partial inspection is required the location of the joints selected for testing shall be agreed by the Engineer.

Should any of these welds prove to be defective on inspection, the number of welds to be tested in that system shall be twice that originally required. Should any of the second increment welds prove to be defective, then all the welds in that system shall be tested.

Weld defect acceptance levels shall be in accordance with Table 2 of BCSA document No 203/94 or AWS D1.1 as appropriate.

G2.1.5 Vertical site welded storage tanks

The storage tanks and associated valves and pipework shall be designed, manufactured and tested in compliance with API 650 and associated specifications. The Contractor shall recognize during material selection and testing the limitations imposed by site and service conditions. Welding process during shop and site fabrication and erection shall be limited to MMA (SMAW), SAW, TIG (GTAW), MIG (GMAW) (excluding short-circuiting mode), and FCAW (excluding self-shielded). For the purposes of welding this component weld procedures, welders, weld operators and non-destructive test operators may be qualified in accordance with ASME/ASTM Codes.

Where required by Code, surface crack detection shall be made by magnetic testing on ferritic materials. All branch welds including reinforcement plates and load bearing fillet welds shall be examined by magnetic testing. Penetrant testing may be applied to non-magnetic materials only.

Spot radiographic examination may be applied in accordance with the Code subject to, as a minimum, all intersections of welds shall be included with a minimum weld length of 75 mm from the intersection and are in addition to the requirements specified in Figure 6.1 for vertical and horizontal joints. In addition where circular openings and reinforcement plates are located within the allowable dimensions specified in the Code the weld joint seam shall be subject to 100 radiographic examination for a distance of 1.5 times the opening diameter from each point of intersection.

The Engineer may determine the locations for spot welds and shall select from welds completed by all welders equally. Radiographs shall be produced, interpreted and presented to the Engineer within 24 hours of completing the weld. The Engineer reserves the right to request additional radiographs at no additional cost.

On completion of erection the tank shall be subject to a water test to a static head determined by the design.

G2.1.6 Castings, forgings and wrought products

All castings, forgings and wrought products shall be subjected by the manufacturer to chemical analysis, material tests and inspections in accordance with the appropriate BS except where otherwise agreed by the Engineer. Inspection should be scheduled in order to detect defects as early as possible, to avoid unnecessary delay in manufacture and delivery of the plant. In case of a rejection influencing the delivery time, written and certified notice must be given in due time to the Engineer.


- G7 -

The Engineer reserves the right to examine and witness acceptance tests, prior to and following weld repairs and subsequent post weld heat treatment, mechanical tests etc, at the material suppliers works.

Weld repair procedures are subject to approval of the Engineer.

G2.1.7 Pressure vessels

All pressure vessels shall be designed, fabricated and tested in accordance with PD 5500 or ASME section VIII. The Engineer reserves the right to verify or witness any activity required by the Specification.

G2.1.8 Valves

All castings and forgings shall comply with the requirements of this Specification and BS 759 or BS 6759 as applicable to the service of the valves. All valves shall be subject to hydraulic test at 1.5 times the PN rating of the valve. In addition valves supplied with butt weld ends shall be subject to radiographic or ultrasonic examination for a length of 75 mm from the prepared weld tip and magnetic particle examination of the weld tip profile.

G2.1.9 Pumps

All castings and forgings shall comply with the requirements of this Specification. In addition the radii, changes in section and butt weld ends of the castings shall be subject to magnetic particle and radiographic or ultrasonic examination unless otherwise agreed by the Engineer. Castings shall be subject to hydraulic test at 1.5 times the design pressure.

Pump rotors shall be subject to ultrasonic examination in the rough machined condition and magnetic particle or dye penetrating examination in the final machined condition unless otherwise agreed by the Engineer.

Dynamic balance shall be carried out on the completed rotor and performance tests carried out on the completed pumps to the requirements of BS EN ISO 9906 and BS EN ISO 5198 as appropriate.

Pumps shall be factory tested with their contact motors.

G2.1.10 Motor driven auxiliaries

All motor driven auxiliaries shall be run at 20 per cent overspeed for two minutes.

G2.1.11 Cranes

Electric overhead travelling cranes shall be designed, manufactured and tested in accordance with BS 466 and BS 2573 or equivalent internationally recognized standards.

Electrical tests on the cranes in manufacturer's works shall include:

a. thyristor and rectifier assembly


- G8 -

a. control gear and wiring

b. contactors

c. motors.

G2.2 Electrical systems and equipment

G2.2.1 General

The equipment provided is subject to inspection and tests by the Engineer during the course of manufacture and on completion in order to ensure compliance with this Specification. The Contractor shall give the Engineer at least 7 days notice of materials for inspection or test. For tests of long duration at least one months notice shall be given.

The Contractor shall provide to the Engineer as soon as practicable after tests have been witnessed three copies of the relevant test certificates. These shall contain details of each test performed. Records, results and calculations of all electrical tests shall be provided.

All tests shall be carried out in the presence of the Engineer unless otherwise agreed in writing. All instruments used shall have valid calibration certificates, and calibration data shall be made available to the Engineer on demand. All the inspection, measuring and test equipment required for inspections and tests shall be provided by the Contractor.

The Contractor shall provide type test certificates for identical or essentially similar equipment which satisfies the Engineer. Such certified results shall be presented to the Engineer for consideration no later than six months after the Contract date.

Six copies of test certificates detailing all the works tests performed shall be issued by the Contractor to the Engineer within two months of completion of works tests on each item of plant or equipment.

G2.2.2 Generator

G2.2.2.1 Inspection and testing during manufacture

The following tests shall be performed, as applicable, during the course of manufacture:

a. Rotor forging and rotor end winding retaining rings. An approved series of non destructive tests.

b. Overspeed. At 1.2 pu rated speed for 2 minutes on complete rotor in hot state. Vibrations of shaft and bearings shall be measured before, during and after the overspeed test.

c. Oil coolers and other fluid/water coolers. Hydraulic pressure test of 1.5 x working pressure applied to both sides of each cooler.

d. Cooler tubes. Hydraulic pressure test of 1.5 x working pressure applied to each individual tube.


- G9 -

e. Rotor winding. High voltage tests as and RSO tests to be carried out as appropriate to the stage of manufacture.

f. Stator core. An approved test at approximately rated flux at rated frequency on the core before winding to give an indication of core loss, to verify the efficacy of the interlaminar insulation and correct assembly.

g. Stator winding. Tests in accordance with IEC 60894 including random sample test.

G2.2.2.2 Routine tests

The following tests shall be carried out on each generator complete with associated excitation, cooling, control and auxiliary equipments:-

a. Winding resistances. The stator and rotor winding resistances and relevant cold state temperatures shall be measured.

b. Phase sequence. The phase sequence shall be checked and permanently marked.

c. No-load saturation characteristic. The no-load saturation characteristic shall be measured in accordance with IEC 60034-4.

d. No-load heat run. The stabilized temperature rises, temperatures and losses at rated voltage and rated speed shall be measured.

e. Short circuit characteristic. The sustained three-phase short circuit characteristic shall be measured in accordance with IEC 60034-4.

The direct-axis synchronous reactance and the short circuit ratio shall be determined from the results of the no-load saturation and sustained three-phase short circuit tests.

f. Short circuit heat runs. The stabilized temperature rises, temperatures and losses at rated current and rated speed shall be measured.

g. Unexcited run. The stabilized temperature rises, temperatures and losses with the generator unexcited at rated speed shall be measured.

h. Temperature rises and temperatures. The temperature rises and temperatures at rated output of the generator shall be predicted from the results of the no-load and short-circuit heat runs and the unexcited run by an approved method.

i. Vibration. Vibration of all bearings shall be measured during the running tests.

j. High voltage tests. The stator shall be tested, with the rotor in position, in accordance with IEC 60034-1. The rotor shall be tested both at standstill and at rated speed in accordance with IEC 60034-1.


- G10 -

k. Insulation resistance. The insulation resistance of both the stator and rotor windings shall be measured before and after the respective high voltage tests.

l. Rotor impedance. The rotor impedance to an alternating voltage shall be measured before and after the running tests.

m. Dielectric measurements. The dielectric loss angle (tan delta), capacitance to earth and dielectric loss energy characteristics shall be measured for each phase of the stator windings.

G2.2.3 Excitation equipment

G2.2.3.1 Thyristor rectifier routine tests

Routine tests in accordance with IEC 60146 shall be performed on each rectifier equipment.

The insulation test voltage shall not be less than the test voltage applied to the generator field winding insulation.

Test details and methods shall be agreed with, and approved by the Engineer.

G2.2.3.2 Excitation transformer routine tests

Transformers for the thyristor rectifier equipment shall be subjected to routine tests in accordance with IEC 60076 and IEC 60146. Test details and test methods shall be agreed with, and approved by the Engineer.

G2.2.4 Generator switchgear

Tests shall be carried out generally in accordance with the requirements of IEEE C37.013 and with an X/R ratio appropriate to generator switching duties.

G2.2.5 Generator transformers

Testing shall be carried out generally in accordance with the requirements of IEC 60076. No load current at 70 per cent, 100 per cent and 110 per cent shall also be measured.

G2.2.6 DC supplies equipment

Performance tests. One battery shall be subjected to the emergency discharge and recharge time requirements of the Specification. Voltage/time, current/time and specific gravity/time curves shall be plotted throughout the recharge period.

The automatic and manual voltage control system and alarm and indication functions of the chargers shall be demonstrated to the satisfaction of the Engineer.

G2.2.7 Protection equipment

All relays shall be subjected to routine tests at the manufacturer's works to confirm that they comply with the claimed performance and design limits.


- G11 -

For measuring relays (ie relays which have a defined setting of the input and/or characteristic quantity subjected to accuracy requirements, eg current, time, etc) these routine tests shall include as a minimum the following:

a. Measurement of the assigned error(s) under reference conditions, ie measuring accuracy and operating time characteristics.

b. Measurement of the resetting ratios.

c. Dielectric tests as specified in Clause 6 of IEC 60255-5, the test voltage being 2 kV rms. All normally open output contacts of all relays shall withstand a test voltage of 1 kV rms.

For all-or-nothing relays, the routine tests shall include a check of relay operation and resetting, together with the dielectric tests described above.

Unless otherwise agreed with the Engineer, all unit protection schemes using either biased differential, current balance or voltage balance principles shall be subjected to heavy current conjunctive tests using the actual current transformer windings which will be used in service. Tests shall be made to prove operating sensitivity, time of operation and to demonstrate stability of the protection under the worst transient external fault conditions. Tests will only be waived if the manufacturer is able to produce type test results for an identical scheme. In this case it will be sufficient to prove that individual component characteristics are identical, eg current transformers are of the same design, have the same magnetization characteristics, knee-point voltage and secondary resistance.

Each circulating current protection scheme designed in accordance with Section G3.12.3 must fulfil the following routine testing requirements:

a. Each current transformer, which must be of the low reactance type, shall be individually tested for turns ratio, secondary winding resistance and excitation characteristic up to a secondary voltage equal to 120 per cent of the “knee-point” voltage.

b. The VA consumption at operation of current operated relays shall be measured and shall not exceed the maximum value declared by the manufacturer.

c. The operating current of voltage relays shall be measured and shall not exceed the maximum value declared by the manufacturer.

G2.2.8 Gas turbine, PCS and auxiliary stand-alone control systems

For each separate control system, the correct operation of all inputs, outputs, control functions, monitoring functions, operator display systems, printing systems and all associated systems shall be tested to a test specification which shall be approved by the Engineer in advance of the factory acceptance testing. The factory acceptance testing shall be witnessed by the Engineer.


- G12 -

G3 SITE TESTS

G3.1 Open cycle plant

The Contractor shall carry out performance tests on completion on the open cycle plant to prove compliance with the contractual performance guarantee of electrical output and overall heat rate. In accordance with the requirements of Section 11 of the Technical Specification.

G3.2 Switchgear and ancillary equipment

Tests before completion. These shall comprise Site testing to demonstrate complete satisfactory operation of the equipment after transport and installation generally in line with the routine tests in the manufacturer's works.

Commissioning and setting to work. This shall include the following:

a. The checking of all connections, and conductivity testing of busbar joints.

b. The checking and ringing through of all small wiring and multicore cables connected to the equipment.

c. Dielectric testing of all primary circuits on the equipment.

d. Insulation resistance measurement of all secondary circuits on the equipment.

e. Primary injection of all protective and metering circuits to check satisfactory operation.

f. The checking for satisfactory adjustment and operation of all circuit breakers, switches, and mechanical and electrical interlocks.

g. Secondary injection tests on relays and instruments to check operating characteristics.

h. Tests to check the magnetism curve, polarity and resistance of current transformers.

i. Final setting of all protection.

j. Secondary injection of voltage transformer circuits.

k. Phasing tests prior to making live.

l. On-load checks of protection, indicating and metering circuits.

G3.3 Transformers

Tests before completion. These shall measure:

a. Insulation resistance of core and windings at not less than 2000 V dc.


- G13 -

b. Insulation resistance of auxiliary wiring.

c. Proving of manual and electrical operation of each device.

d. Operation of equipment in accordance with the overall control scheme.

Commissioning and setting to work. This shall include:

e. Ratio and no-load current at reduced voltages on all tappings. Vector relationship at reduced voltage.

G3.4 Battery equipment

Tests before completion. After erection of the batteries/chargers and switchboards the following tests shall be carried out:

a. The checking of all connections.

b. 500 V insulation testing of all primary and secondary circuits.

c. Primary injection of all protection and indication circuits.

d. The checking for satisfactory adjustment and operation of all circuit breakers, switches and mechanical and electrical interlocks.

Commissioning and setting to work. Upon completion of the above tests, the system performance shall be checked as follows:

a. The charging equipments shall be used to charge the batteries.

b. The performance of the automatic control equipment shall be noted.

c. The voltage/time curve shall be plotted.

d. Each battery in turn shall be floated on total load as stated in Schedule D and the performance of the voltage/current control shall be noted as the load current is varied over the limits stated in Schedule D.

e. The operation of the manual control shall be demonstrated and recorded over the entire range of each charger.

Dummy loads if required for testing shall be provided by the Contractor.

G3.5 Cabling

Routine insulation tests shall be made and recorded on all cables, joints and sealing ends etc.

HV dc tests at 4Uo shall be made between conductors and between conductors and sheath on cables operating between 3.3 kV and 33 kV.


- G14 -

1000 V insulation tests shall similarly be made on LV power cables and dc power supplies cables.

500 V insulation tests shall be applied between all cores and earth on all multicore cables.

On terminations with insulated glands (single core cables) a 1000 V insulation test shall be carried out between armour and/or sheath and earth

G3.6 Test equipment

The Contractor shall provide all the necessary instrumentation, vibration and balancing equipment, recorders, sensors etc with experienced test engineers and staff to carry out these tests.

Six copies of test certificates for all the site tests shall be issued by the Contractor to the Engineer.

The Contractor shall submit his Site test proposals and programme to the Engineer for approval 3 months before site tests are due to commence. The following tests shall be included in the tests to be carried out.

Continuity tests shall be carried out on all earthing systems to ensure that the resistance to earth of all earthed equipment does not exceed 2 ohms.

G3.7 Generator

Dry out. Before any electrical tests take place the insulation polarization index and insulation resistance of the stator winding shall be measured, and if deemed necessary the generator shall be dried out.

Rotor impedance. The rotor impedance to an alternating voltage shall be measured before and after running tests.

Winding resistances. Cold stator and rotor winding resistances and corresponding temperatures shall be measured. The rotor winding resistance shall be measured before and after running tests.

Characteristic curves. Generator open circuit and short circuit curves shall be measured and plotted.

Temperature rise. Temperature rise tests shall be carried out at rated output. The test shall be run until steady temperatures are obtained. These tests can be combined with the overall efficiency tests.

G3.8 Excitation system

Tests shall be carried out on each machine to demonstrate that the equipment performs correctly and as specified, and that stability margins are adequate.


- G15 -

A commissioning test programme for the completely assembled excitation equipment shall be agreed with and approved by the Engineer and shall at least include the following:

a. verify trigger pulse sequences, triggering current magnitude and rate of rise applied to thyristors;

b. demonstrate that phase currents to thyristor rectifier are balanced over operating range and that parallel connected thyristors share current adequately;

c. determine settings for automatic regulator adjustable controls for test performance with generator on open circuit, and demonstrate, for example by step response or harmonic response tests, the stability margin over the full operating range of generator terminal voltage and frequency;

d. demonstrate start up and shut down sequences;

e. demonstrate operation of limiters and set at required operating point;

f. demonstrate generator steady state performance and verify margin between underexcitation limiter setting and theoretical steady state stability limit;

g. demonstrate operation of power system stabilizer;

h. demonstrate VAr sharing between generators;

i. demonstrate performance on full load rejection;

j. demonstrate transfer between automatic and manual control by simulated fault and by deliberate selection, and transfer between manual and automatic control;

k. demonstrate operation in manual control;

l. demonstrate all control functions, alarms and protection circuits, and

m. temperature rise test at rated generator load, over-excited to verify cooling conditions for the exciters are adequate.

G3.9 Control and instrumentation

Installation and commissioning shall be generally in accordance with BS 6739.

Test documents shall be produced and shall include check lists to be witnessed by the Engineer. These test documents shall contain agreed acceptance criteria.

The Contractor shall record the results of all calibration checks and loop tests on suitable check sheets such as those examples given in BS 6739.


- G16 -

Commissioning will in general be achieved in the following stages:

a. Calibration and performance tests prior to operation.

This shall include:

i. Calibration of total loop where possible.

ii. Performance check using simulated input/output conditions.

iii. Sequence and interlock equipment proving.

iv. Control loop functions using simulated conditions.

v. Software testing.

vi. Redundancy tests.

vii. Data communications checks.

b. Cold plant interface tests:

These shall be carried out with equipment connected to the main plant and shall as far as possible demonstrate that plant may be controlled safely and to specification.

c. Hot plant performance tests:

These shall be carried out in conjunction with the main plant in operation. They shall include on-line tests to demonstrate that all control and plant monitoring equipment are within specification in an operating environment. Tests may also involve co-operation during any required plant performance guarantee testing.

G3.10 Main connections

After erection at Site the main connections shall be subject to dielectric, conductivity and temperature rise tests to prove compliance with the specified requirements.

G3.11 Earthing and lightning protection systems

Each electrode shall be tested before being connected to the underground copper grid earthing system. Continuity tests shall be carried out on all earthing systems and lightning protection systems to ensure that the resistance to earth of all equipment and terminations does not exceed the design value.

G3.12 Lighting and small power

After completion and before being energized the installation shall be inspected and tested. All tests required by Part 7 of BS 7671.shall be carried out.


- G17 -

After energization, the operation of all lighting and small power circuits and devices shall be demonstrated, including any emergency circuits.

Illumination levels for all normal and emergency systems shall be measured.

The Electrical Installation Certificate in Appendix 6 of BS 7671 shall be completed in its entirety and issued to the Owner.


- H1 -

SCHEDULE H LIST OF SPARE PARTS AND CONSUMABLES

H1 List of recommended and optional spare parts (Tenderer to give details)

Part Quantity Price*

Document No. 62010/IPA/000001 Rev A 0654S180_SCHEDH.DOC/S1/2/PMO

- H2 -

H2 List of recommended consumables (Tenderer to give details)

Part Quantity Price

Document No. 62010/IPA/000001 Rev A 0654S180_SCHEDH.DOC/S1/2/PMO

- J1 -

SCHEDULE J LIST OF SPECIAL TOOLS AND EQUIPMENT

(Tenderer to give details)

Part Quantity

Document No. 62010/IPA/000001 Rev A 0654S200_SCHEDJ.DOC/S1/1/PMO


GAS TURBINE POWER STATION VOLUME 3 ENQUIRY DRAWINGS AUGUST 2004

- 1 -

LIST OF REVISIONS

Current Rev.

Date Page affected

Prepared by


Checked by (quality

assurance)

Approved by

A

Aug 2004

All


J SAMS S WATT

J LIDDLE

MA MITCHELL

J LIDDLE

Original

Aug 2004

All

REVISION DETAILS


A

Aug 2004

All



(i)

CONTENTS

Page ENQUIRY DRAWINGS

____________________________


- 1 -

GENERAL

Section 4 and Schedule E of the Specification shall be read in conjunction with the Enquiry drawings, as listed in this Volume.

The Tenderer is advised that these drawings are provided for information only and do not relieve the Tenderer of their obligation to fully assess the plant and provide functioning systems that comply with all requirements detailed in the Contract.

Drawing No Title

62010/IPA/M000001 Fuel oil supply system flow diagram

62010/IPA/M000002 Fuel gas supply system flow diagram

62010/IPA/M000003 Instrument/Service air flow diagram

62010/IPA/M000004 Water services flow diagram

62010/IPA/M000005 Fire fighting system flow diagram

62010/IPA/M000006 Unitised cooling water flow diagram

62010/IPA/E000001 Single line diagram

62010/IPA/I 000001 Indicative PCS configuration diagram



GAS TURBINE POWER STATION VOLUME 4 APPENDICES AUGUST 2004

- 1 -

LIST OF REVISIONS

Current Rev.

Date Page affected

Prepared by


Checked by (quality

assurance)

Approved by

A

Aug 2004

All


J SAMS S WATT

J LIDDLE

MA MITCHELL

J LIDDLE

Original

Aug 2004

All

REVISION DETAILS


A

Aug 2004

All



- i -

CONTENTS

Appendix A [Ground Investigation Report]

Appendix B [Ground Pollution Report]

Appendix C [Seismic Study]

Appendix D [Environmental Report]

____________________________


Spec Power Plant TGG Ciclo Aberto Iraque

Documents

Transcript of Spec Power Plant TGG Ciclo Aberto Iraque