medium Voltage Composite Insulators

R1-082:2007

CEB STANDARD

33kV- COMPOSITE INSULATOR FOR COASTAL AREAS

CEYLON ELECTRICITY BOARD SRI LANKA

Specification for

33kV- COMPOSITE INSULATOR FOR COASTAL AREAS CEB Standard R1-082:2007 CEYLON ELECTRICITY BOARD No. 50, Sir Chittampalam A. Gardener Mawatha, Colombo 2. Sri Lanka Telephone: 94-1-430471, 421720 Facsimile: 94-1-430473 E-mail : [email protected]

CEB STANDARD R1-082:2007

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CONTENTS PAGE 1. Scope 2 2. System Parameters 2 3. Service Conditions 2 4. Applicable Standard 2 5. Basic Features 3 6. Quality Assurance 5 7. Additional Requirements 5 8. Information to be Supplied with the Offer 6 9. Sample Study 8 10. Inspection and Testing 8


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SPECIFICATION FOR MEDIUM VOLTAGE COMPOSITE INSULATORS

1.0 SCOPE This specification covers the general requirements of the design, manufacture, testing

supply and delivery of medium voltage composite insulators complete with hardware for 33kV overhead distribution lines in the coastal area.

The composite insulators shall be of the following types a) Long Rod Insulators for conductor tension and suspension application b) Pin Insulators for intermediate point application 2.0 SYSTEM PARAMETERS a) Nominal Voltage - 33kV b) System highest voltage - 36kV c) System frequency - 50Hz d) Number of phases - 03 e) Method of earthing - Non effectively earthed f) System fault level - 13.1 kA 3.0 SERVICE CONDITIONS (a) Annual average ambient temperature - 30°C (b) Maximum ambient temperature - 40°C (c) Maximum relative humidity - 90%

d) Operational Altitude - From MSLto 900 m above MSL e) Isokeraunic (Thunder day) level - 90 days. f) Environmental condition

i) Humid and heavily polluted with deposits of sand, dust and salt from the sea,

industrial and agricultural pollution ii) Maximum temperature difference form day to night 250C. iii) Prolonged periods without rain (up to 10 months) iv) Long summer periods with lots of sunshine.

4.0 APPLICABLE STANDARDS

The composite insulators shall be designed, manufactured and tested in accordance with

the requirements of the latest published edition of the standards specified below and amendments thereof

a) IEC 61109; 1992 - Composite insulators for A.C. overhead lines with a

nominal voltage greater than 1000V.

b) IEC 60383 : 1980 - Insulators for overhead lines with a nominal voltage above 1000V.

All aspects, tests, etc. not covered by the above IEC standards shall be executed

according to this standard to the fullest satisfaction of the purchaser.


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5.0 BASIC FEATURES 5.1 Design and Construction The composite insulator shall have a core and insulating housing & whether shed housing

both manufactured by the same manufacturer and steel / aluminium hardware components for attaching it to the support and conductor.

5.1.1 Core The insulator core shall be made of brittle fracture-resistant electrical grade epoxy / vinyl

ester / Isopolyester based fiberglass rod to achieve maximum failing load. The core shall be mechanically and electrically sound, free from voids, foreign substances and manufacturing flaws.

Also the design shall be such as to ensure that the core is totally encapsulated and fully sealed, from the live to the earthed ends, by the insulating material from the environment, in order to avoid ingress of moisture. If any tacky substances are used as sealers, they shall not be exposed to environmental influence.

5.1.2 Housing and Weathersheds The housing and Weathersheds shall be made of silicone rubber material in order to maintain their hydrophobicity during long term service in critical environments. A minimum thick sheath of 3.0 mm of Silicone Rubber shall be extruded or injection moulded on the reinforced fiberglass rod. The polymer sleeve and weathershed insulating material shall have a chemical structure of 100 percent silicone rubber before fillers are added. The silicone rubber shall be firmly bonded to the rod, be seamless, smooth and free from imperfections. The strength of the silicone rubber to rod interface shall be greater than the tearing strength of the silicone rubber. The weathersheds shall be firmly bonded to the sheath, vulcanized to the sheath or moulded as part of the sheath and be seamless smooth and free from imperfections. The strength of the silicone rubber weathershed to sheath interface shall be greater than the tearing strength of the silicone rubber. Weathersheds shall be at intervals to provide optimum electrical performance and the weathershed designs should provide a protected bottom surface that tends to keep dry in wet conditions. The insulator shall be capable of withstanding high pressure power washing. A power wash test shall be performed on polymer insulators to demonstrate that the units can be power washed. This test shall be a water spray at a shed seam approximately 3 meter from the insulators. The spray shall be a solid stream through a 6mm diameter nozzle at 3.79Mpa for a period of ten minutes. There shall be no signs of water entering through or under the outside weathershed into the core or at the polymer hardware interface into the core.

The gap between hardware base and housing shall be sealed by an elastomer with permanent elasticity. The sealing shall stick permanently to the surface of the material as well as to the housing.

The base should be attached to insure a uniform distribution of the mechanical load to the rod.


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5.1.3 Hardware The hardware components for clamping conductors shall be of the following types i) Bolted type tension clamp ii) Crimp type tension clamp iii) Suspension clamp The bolted type tension clamp shall be of the 3 bolt type, made of aluminium alloy, suitable for accommodating raccoon conductor as shown in the drawing no. DS&S/2007/82A-R1 The compression type tension clamp for Elm conductor shall be of single part fitting made of aluminium alloy and for Lynx conductor it shall be of two part fitting made of steel and aluminium alloy with jumper socket as shown in the drawing no. DS&S/2007/82B-R1 and as requested in the schedule of prices. The suspension clamp shall be made of aluminium alloy suitable for accommodating Elm / Lynx conductors as shown in the drawing no DS&S / 2007/ 82C-R1. as requested in the schedule of prices.

The hardware component required for mounting the insulator to the cross arm shall be U shackle for long rod insulator and stud for line post insulator as shown in the relevant drawings. All the steel hardware component shall be galvanized to protect them against corrosion. 5.2 Long Rod Insulators

The long rod insulator shall be of type A as per IEC 60383 and as shown in the drawing No. DS&S/2007/82A,B,C-R1 with hardware for fixing the conductor tension (bolted type / crimp type) /suspension clamps on one and U shackle shall be provided on other end (for mounting the insulator to the cross arm) shall be provided..

The long rod insulators shall be supplied complete with necessary hardware such as galvanized steel U shackle / tension clamp (bolted type / crimp type) / suspension clamp as shown in the drawing and as requested in the schedule of prices. 5.3 Pin Insulator

The Pin insulator shall be of type A as per IEC 60383 and as shown in the drawing No.DS&S / 2007 / 82D-R1. The conductor grove of 16 mm radius shall be provided on the top (head) of the pin insulator for accommodating conductors as indicated in the Clause 5.5 - Technical requirements and as requested in the schedule of prices.

The pin insulators shall be supplied complete with necessary hardware such as galvanized steel pin with nut spring washer and a lock nut for mounting the insulator to the channel iron cross arms as shown in the drawing. 5.4 Galvanizing

All steel hardware components shall be galvanized after their machined bent or worked operations of any manner. The zinc coating shall adhere tightly to the surface of the base metal. The zinc coated parts shall not have any un-coated spots.


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The coating shall be uniform and free from blisters, flux, black spots, dross, tear drop edges, flaking zinc, rough appearance and in general shall be smooth, clean and unscarred when received. The minimum thickness of the coating of the steel or iron base will be 80 micron. 5.5 Technical Requirements a) Rated Voltage kV - 36 b) Minimum Creepage Distance mm - 1000 c) Mechanical failing load (min.) i) Long rod Insulator (tensile load) KN - 70/80/100 ii) Line post Insulator (cantilever load) KN - 12 d) Dry lightning withstand voltage (peak) kV - 170 e) Wet power frequency withstand voltage kV/min - 70/1 Duration - 1

f) Radio Interference level at 22kV - 30db

g) Conductor applicable - Raccoon - Lynx - Elm 6.0 QUALITY ASSURANCE Manufacturer shall possess ISO 9001 quality assurance certificate for manufacture of FRP

core rod and composite insulators of 36kV rating and above at the plant where the manufacture is done. Certified copy of the ISO certificate as true copy of original by the manufacturer shall be furnished.

7.0 ADDITIONAL REQUIREMENTS 7.1 MARKING Each insulator shall be moulded with the name or trade marked of the manufacturer, the

year and week of manufacture and the specified mechanical load. The marking shall be legible and indelible.

7.2 Routine Tests

The following routine test according to IEC 61109 and IEC 60383 shall be carried out on all insulators and the routine test report shall be made available for the observation of the CEB inspector at the time of inspection.

i) Identification of the composite insulators ii) Visual examination iii) Mechanical routine test 7.3 Packing All insulators shall be packaged in individual weatherproof containers to protect the

weathersheds against damage during shipping. The containers should be weatherproof and designed to be removable by hand without cutting.

Each shipping container shall have a packing list and in addition, shall be marked with the

following information.


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a) Descriptive name b) Rated voltage c) Quantity packed in container d) Contract and lot number e) Gross weight of container f) Volume of container g) Applicable standard 7.4 Guarantee The insulator manufacturer shall have a minimum of 15 years experience in the field of

manufacturing FRP core rod and composite insulators. The supplier shall submit to the purchase a letter of guarantee that all materials used in the

manufacturing of the insulators will be durable and able to withstand under specified service and Climatic conditions for at least 20 years.

8.0 INFORMATION TO BE SUPPLIED WITH THE OFFER

The bidder shall submit the following together with the offer. a) The catalogues indicating the model No. and technical literature b) General outline and cross-section drawing of the insulator (All data and descriptive material shall be in English and all dimensions shall be in metric units.) c) Quality assurance certificate conforming to ISO 9001 d) Completed and filled-in schedule of guaranteed technical particulars e) Reference list including quantity of the supplied insulators. f) Test Certificates as per Clause 8.1 and 8.2 8.1 Design Tests The following Design Test Certificates conforming to IEC 1109 shall be furnished as applicable i) Tests on interface and connection of metal fittings. ii) Assembled core load-time tests iii) Tests of housing: tracking and erosion Test iv) Tests for core material 8.2 Type Tests The following Type Test Certificates conforming to IEC 61109 shall be furnished as applicable i) Dry lightning impulse withstand voltage tests. ii) Wet power frequency withstand voltage test iii) Mechanical load - time tests

All electrical tests for the insulators supplied under this specification - design, type, sample and routine, shall be performed and evaluated in accordance with IEC Standard 1109, unless stipulated otherwise in this specification.

The test of housing (design test) will include min 5000 hours aging test under operating voltage, acc to Annexure C of the above standard. The mechanical tests shall be performed and evaluated in accordance with IEC 60383.

8.3 Supply Record


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Supply Record indicating the sales of composite insulators for last 15 years shall be furnished indicating quantities and year of sale. The manufacturer shall have supplied composite insulators to a minimum of ten utilities outside the country of manufacture Test Certificates furnished shall be based on the Type Tests conforming to the relevant standard. The Test Certificates shall clearly identify the equipment showing the manufacturer's identity, Type No. and basic technical parameters, and shall be from a recognized Independent Testing Authority acceptable to the Purchaser.

Offers of Bidders who fail to furnish the above particulars and sample as requested in clause 9.0 will be rejected. 9.0 SAMPLE STUDY

One sample of the make and model of the item quoted shall accompany the tender to facilitate analysis and evaluation of the Bid. While analysing samples, the Purchaser reserves the right to check dimensions, inspect workmanship and perform essential tests as prescribed in relevant standards.

10.0 INSPECTION AND TESTING 10.1 Inspection The selected Bidder shall make necessary arrangements for Engineers of the CEB to inspect

manufacturing processes and testing facilities available with the manufacturer and also to witness acceptance /sample tests on the composite insulator offered.

10.2 Acceptance/Sample Tests Following acceptance shall be witnessed by the CEB Inspector.

i) Mechanical failing load test ii) Dielectric test iii) Electro mechanical load test iv) Power Wash Test – Certifying that there shall be no signs of water penetration

through the housing or Weathersheds to the insulator core as per clause 5.12- para 6

11.1 Annex Annex A – 1 Dr. No DS&S / 2007/ 82A- R1-Composite tension insulator set 70kN Annex A – 2 Dr. No DS&S / 2007/ 82B- R1-Composite tension insulator set 100kN Annex A – 3 Dr. No DS&S / 2007/ 82C- R1-Composite suspension insulator set 70kN Annex A – 4 Dr. No DS&S / 2007/ 82D- R1-Composite post insulator Annex B – Schedule of particulars to be filled by the manufacturer


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ANNEX A

SCHEDULE OF GUARANTEED TECHNICAL PARTICULARS FOR MEDIUM VOLTAGE COMPOSITE INSULATORS

(To be filled by the Bidder)

Pin Tension Suspecsion

1) Name of Manufacturer & country of origin of - a) Core Rod - b) Housing/Whethershed - c) Composite insulator - 2) Model/Reference/Catalogue number - 3) Applicable Standards - 4) Specified mechanical load(Tensile/cantilever) kN - 5) Dry lightning impulse withstand voltage (peak) kV - 6) Wet 1 min. power frequency withstand voltage kV - 7) Material

a) Core material - b) Housing and weathersheds material - c) Sealing material - d) End fittings material - i) Bolted type Conductor Tension clamp - ii) Compression type conductor tension clamp - iii) Conductor suspension clamp - iv) Anchor Shackle - v) Cotter, Split Pin - e) Average coating thickness of fittings -

8) Nominal length mm - 9) Creepage distance mm - 10) Net weight kg - 11) Whether the Dimensional Drawings furnished Yes/No- 12) Whether the quality assurance certificates furnished Yes/No- 13) Whether the type & design test certificates issued by

recognized Independent testing authority furnished Yes/No- 14) Whether the supply record for last 15 years

indicating utilities outside the country of manufacture is furnished Yes/No -

15) Whether the Acceptance Test will be carried Yes/No - 16) If Yes, then place of testing of Accepting tests 17) Standard package

a) Weight of crate kg - b) Package volume m3 -

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SEAL AND SIGNATURE OF THE MANUFACTURER /

DATE------------------- ibm/thaya/emcompo

medium Voltage Composite Insulators

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