Industrial Book 1 - Seridamai• Cathodic protection cable - XLPE/PVC, HMWPE, HALAR, Armoured,...

INTRODUCTION

INTRODUCTION

Wilson Taylor Asia Pacific4Page 1

WILSON TAYLOR COMPANY PROFILE

Wilson Taylor Asia Pacific (WTAP) is a Cathodic Protection company based in Singapore and was formed in 1997. The owners and managers together have many years experience in cathodic protection. WTAP also has a subsidiary company based in Hong Kong and Shanghai respectively called Wilson Taylor Far East Limited (WTFE) and Wilson Taylor Trading (Shanghai) Limited.

WTAP operates a foundry in Singapore (certified ISO 9001:2008) located near to the shipyards to produce sacrificial anodes for the marine, industrial and offshore markets. The companies also have foundry arrangements in China at Shanghai and Qing Dao which is approximately 1,000 km north of Shanghai.

The region covered by the two above companies includes China, India, Indonesia, Hong Kong, Japan, Korea, Malaysia, Philippines, Singapore, Thailand, Taiwan, Vietnam and Middle East and stocks of sacrificial anodes are carried at a number of the above locations.

In addition to sacrificial anodes, the companies also sales and service of impressed current cathodic protection systems and anti-fouling systems as well as offering throughout the region industrial cathodic protection covering consultancy, feasibility studies, comprehensive site surveys, design, specification and drawing services, turnkey design, supply, installation and commissioning, training of customers’ personnel and materials supply.

For the marine sector, the companies work with Associates in many parts of the world in recognition that ship owners, shipbuilders and ship repairers are all situated in different global locations. This unique network covers the supply of anodes from strategically placed foundries in Malaysia, Greece, Middle East, China, USA and all are certified ISO 9001:2008.

WILSON TAYLORASIA PACIFIC

QUALITY SERVICES WORLDWIDE•Turn Key Projects Engineering & Design Corrosion Surveys Consulting Testing & Commisioning Material Supply• • • • •

Key Benefits for Structures (Marine,Offshore & Industrial) protected byCathodic Protection Systems

Key Benefits for Water Intakepipelines protected by Anti-fouling Systems

• Reduce maintenance costs

• Lower costs on using high standards coatings

• Increases life of the structures

• Only solution to corrosion of inaccessible areas of

steel such as the base of storage tanks

• Reduces likelihood of leakage from buried and

submarine pipeline caused by corrosion

• Reduce repair bills for vessels

• Longer intervals between dry dockings

• Higher resale value

• Prevent fouling built-up

• Protect pipeline against corrosion

• Kills Sulphur Reducing Bacteria (SRB)

• Full Automatic control

• Lowers maintenance costs

Page 24Wilson Taylor Asia Pacific

OUR PRODUCTS


INDUSTRIAL PLANT PROTECTION

SHIP’S HULL & BALLAST PROTECTION

OFFSHORE STRUCTURE PROTECTION

ANTI-FOULING SYSTEM

Pier, jetty, tidal gates and any other structures in contact withWater (salt & fresh) or Pipelines, Piles, or storage tanks incontact with soil, sand or concrete.

Any area of steel, either in the ballast tank or ship’s hull thatis immersed in sea-water.

Submarine pipelines and structures of drilling rigs &platforms submerged in sea-water.

Customized design suitable for Marine, Offshore and Industrial plants.Highly effective equipment for controlling anti-fouling for pipelines,

sea-chest, water-boxes exposed to seawater.

Corrosion costs money - money that otherwise would be profit to the owners and investors.

Wilson Taylor Asia Pacific is the major company specializing in Cathodic Protection - the most effective means of controlling corrosion of steel immersed in sea-water, fresh-water or buried in soil, sand or concrete.

Wilson Taylor Asia Pacific undertakes design and consultancy assignments and has world wide capability for the manufacture, installation and servicing of cathodic protection equipments.

Wilson Taylor Asia Pacific is the leader in all three sectors, namely Industrial, Marine and Offshore forcorrosion control utilizing Cathodic Protection.

Wilson Taylor Asia Pacific

PRINCIPAL ACTIVITIES

The principal activities of Wilson Taylor Asia Pacific can be split into four primary divisions; MarineAnodes, Marine Equipment, Industrial, and Offshore.

Cathodic Protection Engineering

Our team of CP specialist, managers, and engineers provide turn-key projects for the protection of structures, either buried underground or immersed in sea water including:

Pipelines, jetties and submerged structures, refineries, process and water treatment plants, storage tank bottoms and internals, buried LPG or Fuels vessels, power station intakes, screens, pumps and concrete structures, sheet steel piling and foundations.

The service encompasses everything from initial consultancy that may include plant site surveys, costevaluation and project design through installation, testing and commissioning, including regular inspection/maintenance checks. In addition to our full-time staff, we utilize independent laboratories for specialist investigations and reports.

Cathodic Protection Materials and Equipment Manufacture and Supply

Wilson Taylor Asia Pacific’s cathodic protection equipments and materials are manufactured andsupplied from our Singapore foundry. We also have exclusive arrangements with major manufacturers worldwide such as for magnesium anodes and other items. Our manufacturing and assembly capability worldwide includes:-

• Blastomatic (Descaling system)

• BioChloromatic (Industrial Anti-fouling)

• Magnesium Block and Ribbons anodes (bare and packaged)

• Silicon Iron (Si-Fe-Cr) anodes (solid and tubular, cabled and canistered)

• Graphite anodes

• Mixed Metal Oxide Titanium anodes (Tubular, Rod, cabled or bare)

• Platinum Titanium/Niobium anodes

• Cathodic protection cable - XLPE/PVC, HMWPE, HALAR, Armoured, Non-armoured etc.

• Zinc earthing electrodes and reference electrodes

• Aluminium and Zinc anodes

• Copper/copper sulphate (perm. and portable) and silver/silver chloride electrodes

• Vessel’s impressed current system “HULLMATIC”.

• Vessel’s Anti-fouling system (MGPS) “INTAKEMATIC”

• Transformer rectifiers, Junction boxes and Test posts – customized, standard

• Monolithic isolating joints, pipeline, insulators and end seals

• Coke breeze and petroleum backfills and earthing materials.

• Anti-corrosion tapes (VISCOTAQ), heat shrinkage sleeves/tubing

• UV Cured GRP coating system (SOLARTECH)

• AC Mitigation Probes & Data Loggers.

INTRODUCTION TOCATHODIC PROTECTION


Cathodic Protection

All immersed metals are susceptible to corrosion if they are not in a state of equilibrium with their environment. The corrosion is electrochemical in nature and occurs in natural or salt water with all but noble metals.

Such corrosion can, however, be suppressed if the metallic surfaces can be lowered to a state of electrochemical stability. This can be achieved either by enveloping the material beneath a stable passive protection film or by reducing the metalermo-dynamic activity to a level at which the energy is insufficient for the corrosion reaction to proceed.

In the latter case protection can be achieved either by means of galvanic action or by the influence of impressed direct current.

Suppression of corrosion by such means is termed Cathodic Protection.

The two electrodes, anode and cathode, and the electrolyte form a cell in which the anode is the corroding electrode and the cathode the protecting electrode. In a cell which has iron (or carbon steel) electrodes and a dilute solution of common salt (or seawater) as the electrolyte the reactions would be -

Electrochemical Theory of Corrosion

The corrosion of a piece of metal may be summarised as the change from the metal to the metalion or the loss of one or more electrons from the metallic atom, viz.

Potential Series

If two pieces of different metals, say iron and copper, are immersed in a salt solution containing ions of both metals, then an electrical difference will exist between them and if they are connected electrically, current will flow between them. Each piece metal in the electrolyte will corrode on its surface and the metal will go into solution as positively charged ions and leave the remainder of the metal negatively charged. The negatively charged metal will attract the positively charged ions and so reduce the tendency for further corrosion of the metal. A balance will be reached when the metal has sufficient negative charge to attract as many positive ions back to its surface as are naturally formed by the metal corroding.

The two metals immersed in the salt solution will come to equilibrium most probably at different electrical potentials when they can be potentiometrically measured. By this method an electrochemical series of metals and alloys can be established; those metals or alloys having a more negative potential are considered to be anodic whilst those having a more positive potential are considered to be cathodic. When any two metals are joined together in an electrolyte, the metal more negative will be the anode and hence corrode: also, the further the metals are from each other in the series, the greater will be the degree of corrosion of the anodic metal ignoring geometrical and size differences of anode and cathode; the other factor to be considered is the resistivity of the electrolyte, where low resistivity enhances the rate of corrosion whilst high resistivity retards it, as, for example, in high purity water. This helps to explain why corrosion occurs more readily in seawater and protective measures (such as cathodic protection) are necessary, whereas in river water, generally, they are not.

If a piece of iron is placed in water, the metallic iron goes into solution as ferrousions and the metal assumes a negative charge from the excess electrons that remain it. The passage of the metallic atom into the solution as an ion is thus equivalent to a flow of electric current from the metal into the solution.

The piece of metal or electrode at which current flows from the metal into the solution or electrolyte, is called the anode and the metal electrode where the current flows the electrolyte into the metal, is called the cathode.

Therefore, in the electrolyte, current flows from the anode to the cathode, whilst in the electrical circuit it flows (or is made to flow) from the cathode to the anode.

The Corrosion Process

Conditions Under Which CorrosionOccurs

Cathodic Protection

Cathodic Protection MethodsThe Nature of Corrosion Attack

Corrosion takes many forms depending on the nature of the metal, the homogeneity of its structure, the nature of the corrosive medium, the galvanic effects between dissimilar metals, possible stray currents from external sources and many other factors. Where possible, the likelihood of corrosion attack and subsequent plant failure is avoided by the correct selection of materials for a particular service. However, in many instances, economics and strength dictate that steel be used for the construction material, especially in the case of large ships, offshore platforms and pipelines. Steel, of all the common construction materials, is one of the most susceptible to corrosion attack under many conditions and, if adequate precautions are not taken, failures due to severe corrosion can result in interruptions or loss of plant operations and in extreme cases, loss of life.

The amount of metal consumed during the corrosion process is generally dependant on the amount of current flowing between the anode and cathode, and the type of metal suffering from corrosion attack. Using steel as an example, one ampere of current discharging from an anodic area will result in consumption (corrosion) of approximately 9 kilograms of steel in one year. If the anodic area of the steel was very small in relation to the cathodic area, this would result in extremely severe localised corrosion and deep penetration of the steel

For a metal to suffer from galvanic corrosion, certain conditions must be met. These are:

1) There must be an anode and a cathode.2) An electrical potential difference must exist

between the anode and the cathode. (Thispotential can result from a variety of conditionssuch as non-uniform distribution on elementswithin structural steels, or through the proximityof dissimilar metals).

3) There must be an electrical continuity betweenthe anode and the cathode. (This can be the struc-tural steel itself, or direct contact betweendissimilar metals).

4) The anode and the cathode must be immersed inan electrically conductive electrolyte such as wateror soil. For corrosion to occur, this immersionneed not be continuous.

Once the above conditions are met, an electric current will flow between anode and cathode and metal will be consumed at the anode.

within a very short period. Fortunately, corrosion currents of this magnitude are seldom encountered. However, even a very low corrosion current of say I milliamp, if restricted to a very small anodic area, could result in severe pitting and deep penetration of the steel over a number of years. Conversely, if the anodic area is very large in relation to the cathodic area, the current flow from the anode is very low in terms of current density per unit area, and any corrosion that occurs will be lower as consumption of the steel will be evenly distributed over the whole of the anodic area.

As corrosion occurs where current flows from the metal, and does not occur where the current is collected or flows into the metal, it follows that if current is caused to flow onto the entire metal surface then corrosion will cease. This is the basis of Cathodic Protection.

The necessary current required to prevent corrosion be provided by one of the two methods. The first method is to provide a metal of more negative value in the galvanic series than the metal to be protected. This additional metal will become the anode in the corrosion cell and will be consumed whilst flowing current into the cathode (this is the whole of the metal being protected). Metals used in this way are normally referred to as sacrificial anodes. Typical metals used as sacrificial anodes are alloys of zinc, aluminium and magnesium.


ANODIC AREA

CATHODICAREA

ELECTROLYTE


The second means of providing cathodic protection is by the impressed current method where an external source of d.c. current is used to pass current through anodes manufactured from materials such as platinum, high silicon iron and others. The anode materials normally utilised for impressed current systems have a very low consumption rate for a given current output compared to sacrificial anode materials, and systems designed to provide long service lives only require anodes of relatively small dimensions.

Cathodic Protection and Coatings

Choice of Cathodic ProtectionSystem

Cathodic protection can be utilised as the sole means of preventing corrosion on a buried or submerged steel structure, or alternatively can be used in conjunction with a suitable protective coating to provide a combined anti-corrosion system. In a combined system, the main corrosion protection is provided by the applied coating and cathodic protection is used to prevent corrosion of the structure in areas of coating damage (and defect), and to counteract the gradual deterioration of the coating system over a period of time.

Generally, sacrificial anode cathodic protection systems are preferred where current and life requirements are fairly low, or for larger systems where maintenance of the system during its operational life would be difficult or impractical. Impressed current cathodic protection systems tend to provide a more economic solution to corrosion problems where current and life requirements are high and where maintenance requirements for this type of system do not present problems. Additionally, because the current to the anodes is provided from an external power source, it is possible to achieve finer control of the system output to suit any changes in the operational environment.

ANODE CATHODE

ELECTROLYTE

ANODE CATHODE

ELECTROLYTE

APPLICATION OFCATHODIC PROTECTION

Application of Cathodic Protectionto Industries

Cathodic Protection is an economical and highly effective means of controlling corrosion for a wide variety of land-based industries.

Whereas steel immersed in sea-water creates the most common corrosion problem for cathodic protection techniques to handle, there are other electrolytes such as saline mud and soil that will cause corrosion of steel in a similar way.

Applications

Design Criteria

Wilson Taylor Asia Pacific offer an expert design service to ensure that the system installed will do the job expected of it in the most cost-effective manner possible.

This process is especially important with existing structures where some deterioration of the steelwork and original protective paint coating may already have occurred. The factors considered before recommending a system include.

The surface area of steel structure in contact with an electrolyte.The extent, type and condition of any protective coatingapplied to the structure.The resistivity of the electrolyte.The required operational life of the cathodic protectionsystem.The availability of a suitable AC electrical power supply (inthe event that an impressed current system is required).The extent of electrical continuity between or within thestructure to be protected.The possibility of interference with, or current drainage from,the installed system due to the proximity of any adjacentburied or submerged.

This analysis defines the job to be done. The next process is todecide whether an impressed current or sacrificial anodes systemis preferable.

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Cathodic Protection is an ideal means of inhibiting corrosion of steel structures such as jetties, pipelines, power stations, sea water cooling systems, storage tanks, foundation piling and reinforcing bars in concrete.

Paint or other coatings are seldom sufficient protection on their own as they are always vulnerable to mechanical damage or imperfections at the time of application. Cathodic Protection systems can be used alone or in conjunction with coatings of various types.


System Choice

There are many factors effecting the choice between an impressed current system and a sacrifical system. Although an impressed current approach can provide the most economical solution, the requirement for regular servicing and maintenance means that a more expensive sacrificial anode system is preferable, especially if suitable on-site staff are not available to carry out the servicing procedures.

As a general rule, economics is the key determining factor, with sacrificial anodes often being more suitable for smaller systems while impressed current systems may be more suited to larger installations.

There is then the question of which of the many anode materials available to use for the system. The Cathodic Protection Engineer will, prior to specifying any particular anode material, conduct a full analysis of the environment conditions prevailing for the project. Material selection will be based on the results of this study.

EQUIPMENT LIST


Silicon Iron Anodes

Silicon iron provides a low cost anode material for impressed current systems in a wide variety of industrial applications. It is a material that corrodes relatively slowly, is very stable and offer a long life at an economical price.

Characteristics

For use in sea-water, the performances of silicon iron is improved by the addition of chromium.

For on-shore installations where the anode is placed directly in the ground and saturated, a low resistance carbonaceous backfill is installed around the anode.

Two different alloy formulations are available to suit differing applications. Both are based on internationally recognized specifications, in accordance with BS 1591:1975. High Silicon iron is composed of silicon, manganese, carbon, sulphur phosphorus and iron. Silicon iron chrome has the same composition but with the addition of chrome.

Materials

Silicon Iron Anodes for ImpressedCathodic Protection

Wilson Taylor Asia Pacific silicon anodes are available with or without chromium additions and in a standard range of sizes and types to suit most applications.

Normal Anodes

These anodes are manufactured without any chromium and are suitable for the majority of land based cathodic protection installations where high chloride environments will not occur.

These anodes were developed for use in areas of high chloride concentration such as sea water and saline mud, and for applications where temperatures exceed 50 ºC.

Chromium Anodes

Nominal anode composition

Nominal anode composition

Anodes with Cable Tails

Anode Composition

Anode blanks are available, on fittings, in single ended and double ended form over the complete Wilson Taylor Asia Pacific range. The standard cable to anode connection is of the tube and taper pin type, but other connection methods can be provided on request.

Wilson Taylor Asia Pacific tubular, centre connected anodes are supplied with a special compression connection which provides excellent mechanical strength and electrical continuity.

Wilson Taylor Asia Pacific silicon iron anodes can be provided in any of the following forms to suit client and project requirements:

Wilson Taylor Asia Pacific can provide all types of silicon iron anodes with factory connected cable tails.

2The standard cable tail is a 5 metre long 25mm stranded copper conductor with XLPE insulation and PVC sheath for all single and double ended anodes. The tubular anodes do not have standard cable tails, but will be supplied with attached cables to suit clients requirements. Alternative cable tails such as Kynar can be provided on request.

SiliconManganeseCarbonChromiumIron

(Si)(Mn)(C)(Cr)-

14.5% approx.0.75% approx.0.95% approx.4.5%Remainder

SiliconManganeseCarbonIron

(Si)(Mn)(C)(Fe)

14.5% approx.0.75% approx.0.95% approx.Remainder

IMPRESSED CURRENT ANODES


SILICON IRON ANODE

The complete range of Wilson Taylor Asia Pacific silicon iron anodes are available as pre-packed units for ease of installation surrounded by low-resistivity compacted carbonaceous backfill within a sturdy steel canister.

Pre-packed canister anodes are less likely to be damaged in transit, and are easily installed on site. Wilson Taylor Asia Pacific canister anodes can be provided with standard or special cable tails to suit your requirements, and may be installed in the ground vertically or horizontally.

Pre-packed canister anodes

Where the standard range of Wilson Taylor Asia Pacific silicon iron anodes are not suitable for a particular project, a range of special anodes can be provided for applications such as service ducts, condensors, heat exchangers and reinforcement bars in concrete, details are available up on request.

Wilson Taylor Asia Pacific Silicon IronAnodes for Special Applications

Standard Anode Range

Applications

Silicon iron anodes are suitable for a wide variety of industrial applications. In particular, pipelines, storage tanks, sea-water cooling systems and jetties.

Alternative sizes can be supplied on request.



Wilson Taylor Asia Pacific PlatinisedTitanium Anodes for ImpressedCurrent Cathodic Protection

Wilson Taylor Asia Pacific platinised titanium anodes are available in a wide range of sizes, shapes and types to suit the majority of marine and onshore applications, and are specially designed and manufactured for each project to ensure suitable output and life characteristics.

Titanium, which is used as the substrate or carrier for the platinum coating, is a good conductor of electricity but will not readily emit current due to the electrically insulating natural protective film of oxide that is formed on its exposed surface. The extremely thin electroplated coating of platinum, deposited on the titanium substrate, overcomes this problem because any passivation film that forms on the platinum is electrically very conductive and readily emits current into the electrolyte.

Anode Characteristics

During operation of a platinised titanium anode, the platinum is consumed. The actual consumption rate of the platinum is dependant on many factors, including the nature of the electrolyte and the current density at which the anode is operating.

To permit flexibility of anode design, the platinum coating can be electro deposited onto the titanium at different thicknesses during manufacture. The most common thicknesses being 2.5 microns, 5 microns and 7.5 microns, although thicker coatings can be provided for particularly severe applications.

Anode Consumption Rate

Standard Anode Elements

Wilson Taylor Asia Pacific platinised titanium anodes are normally supplied as complete assemblies with cable tails and mounting arrangements. These assemblies incorporate elements in rod, tube and sheet form.

Wilson Taylor Anode Assemblies

Using these standard elements, Wilson Taylor Asia Pacific will supply suitable anode assemblies ready for installations. The anode assemblies are complete with a factory connected cable tail of suitable length and

current carrying capacity. The cable tail insulation is XLPE/PVC as standard, but alternative insulation types such as KYNAR can be provided up on request.

The cable connection to the anode element is carried out within a purpose-made PVC unit and is fully encapsulated with a waterproof epoxy resin to prevent failure in service. This type of connection/encapsulation unit has been destructively tested after 10 years operation in sea water and it was found that no water ingress had occurred and that the connection was mechanically and electrically perfect.

Wilson Taylor Asia Pacific produce a wide range of anode mounting units for various applications. Brief details of the various types are listed below:

The type of mounting required is dependant on the type of structure being protected, the life of the cathodic protection system, and the environmental conditions existing on site. The most common forms of mounting are:

With this type of mounting, the anode assembly is suspended from the underside of the structure deck using polypropylene ropes, or similar, on multi-point fixings to limit anode movement, or alternatively with single point fixing and sea bed anchors.

Suspended mounting is most suited to temporary booster cathodic protection systems or for systems with a maximum service life of between 10-15 years with regular maintenance.

Wilson Taylor Asia Pacific AnodeMounting Supports

For Jetties, Piers and OffshoreStructures

Suspension Mounting


Rigid Mounting On Structures

Wilson Taylor Asia Pacific PlatinisedAnodes for Special Applications

With this type of mounting the anode is rigidly mounted on a fabricated framework which maintains the anode at a position remote from the structure.

Pl atinised tit anium a nodes a re n ot suitable for operation at higher than approx. 8.0 volts at the anode in clean sea water. Operation at higher voltage can exceed the anodic breakdown voltage of the titanium oxide film at any exposed area of the titanium substrate. This should not cause failure of anodes during the later years of operational life unless the platinum coating has been unevenly consumed, or at an earlier time if damage to the platinum coating has occurred.

In circumstances where high anode operating voltages are necessary, such as fresh water, or where space limitations require the use of small high output anodes, Wilson Taylor Asia Pacific would recommend the use of platinised niobium anodes where an anode/cathode voltage of up to 100 volts is possible.

Platinised niobium anodes are available in most of the same standard forms as the platinised titanium anodes, but are considerably more expensive due to the high cost of niobium.

The framework is attached to the structure using either pre-welded brackets or suitable clamps. This is a more permanent anode mounting for systems with a long service life and although less maintenance is required compared to a suspended anode it is more expensive both in terms of prime and installation costs. Wilson Taylor Asia Pacific design and manufacture suitable rigid mountings for each particular project.

Anodes for this application are always designed and manufactured for a specific project because of the many variations between systems. A wide range of cantilever, tubular and continuous anode mountings are available together with fabricated rigid mountings.

A range of pre-packaged M.M.O. anodes is available, the anode assembly being contained within a steel canister surrounded by a suitable low resistivity carbonaceous backfill ready for immediate installation. Alternatively, anodes and backfill can be supplied separately.

Use of this type of mounting is generally restricted to structures requiring a large current capacity where the use of suspended or rigid mounted anodes would not be economical, and where the following conditions are also satisfied.

No future dredging of the sea bed in the vicinityof the anode unit and associated cabling will be carried out.Water depth and configuration of the structureallow positioning of the anode units in suitableareas where current drainage and/or interferenceto other structures will be minimal.

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Sea Bed Mounting

For Cooling Water Systems andScreens

For Onshore Applications


Wilson Taylor Asia Pacific CP Anodes

The substrate, usually titanium is chemically resistent and mechanically robust. The substrate is activated by the MMO coating. The MMO coating has excellent electrocatalytic properties. The evolution of oxygen and chlorine and/or mixtures of the two gases is therefore achieved at a low stable anode potential.

The coating is a mixed metal oxide type which includes precious group metal oxides. The oxide composition has been extensively developed for optimized electrochemical and long lifetime in the different cathodic protection environments.

Composition

Manufacture

The MMO coating is produced by applying solutions containing the precursor materials to the specially treated titanium substrate. It is then thermally treated at elevated temperatures to convert the precursor materials to their oxides. These paint and stove processes are repeated many times until the desired total loading of the MMO coating is obtained. The process achieves very good adhesion properties between the coating and the titanium substrate through mechanical and chemical bonding. Strict Quality Control procedures are adhered to throughout the MMO anode manufacturing process.

The resulting mixed metal oxide - MMO coating - shows extremely good electrochemical and low wear rate (long lifetime) characteristics.

Durability and Service Life

MMO anodes have been especially developed to withstand the simultaneous production of chlorine and oxygen, a condition known to be very severe for anodes. Simultaneous anodic generation of chlorine and oxygen occurs in low salinity brackish/fresh waters. Hydrogen ions co-generated with oxygen gas, particularly in stagnant electrolyte flow, result in very acidic conditions at the coating electrolyte interface.

The MMO anodes are designed to resist acidic conditions and the coating to titanium interface is protected from anodic and chemical attack. The mixed metal oxide MMO coating has a very low wear rate in the range 0.5 to 4mg/Ayr., depending upon the particular cathodic protection application conditions. The long lifetimes are a function only of low electro-chemical wear of the coating providing for stable low anodic operating potential. The MMO anodes are designed for a lifetime of 10 to 20 years or even longer depending upon the application and customer requirement.

Current Outputs

The MMO anodes have high current outputs. The recommended maximum current density depends upon the resistivity and composition of the electrolyte. As with all anode systems the lifetime is a function of the current density.The recommended maximum current output are:

2sea water, 750A/m ;

2brackish/fresh water, 150A/m

2soil (carbonaceous backfill), 100A/m ;

2muds, 50A/m

inside protection of tanks, condensers, pipelines and heat exchangers;outside protection of shiphulls, platforms, piles, dams offshore structures and power station inlets;buried structures (used with carbonaceous backfill)tank bottom protection.

Types of MMO Anodes

MMO anodes are available in all shapes and forms including the following:

Rods, wires, tubes, discs, sheet, expanded mesh, strip and are specially designed and made to the customer application and requirements.

Applications

MMO anodes are recommended for use in a wide variety of cathodic protection applications as for example:



WILSON TAYLOR ASIA PACIFIC MMO AnodesPlatinised Titanium/Niobium Anodes

Specially design for the Cathodic Protection Industry


WILSON TAYLOR ASIA PACIFIC MMO AnodesPlatinised Titanium/Niobium Anodes

Tubular Anodes: Diam. 16, 19, 25, 32, 38, 51 mmto suit clients requirement in the Cathodic

Protection Industry.

Single Tubular AnodesTubular anodes can be supplied with:

Tubular String AnodesTubular anodes mounted to feeder cable for groundbed applications.

- both ends open- one or both ends with welded thread- one or both ends closed with welded cap- one end with welded hook

The following cables are available upon request.XLPE/PVC, KYNAR, HMWPE, EPR, CSP and armoured cables.


TRANSFORMER RECTIFIER UNITS

To ensure complete suitability of equipment for each particular project, Wilson Taylor Asia Pacific do not manufacture a standard range of transformer rectifier units. Each transformer rectifier unit will be designed and manufactured specifically for the application for which it is intended and will incorporate all necessary control and safety features required by the specification.

Wilson Taylor Asia PacificTransformer Rectifier Unitsfor Impressed Current Protection

Industrial Impressed CurrentSystems

Wilson Taylor Asia Pacific can provide a wide range of transformer rectifier units of the following types:

Indoor, air-cooledOutdoor, weatherproof, air-cooledIndoor, oil-cooledOutdoor, weatherproof, oil-cooledOutdoor, weatherproof, oil-cooled, intrinsicallysafe (explosion proof)Plinth or wall/pole mounted dependant on sizeManual or automatic control of outputSingle phase or three phase a.c. power input (dependant on rating)

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Type of Unit Available

Wilson Taylor Asia Wilson Taylor Asia Pacific manually controlled transformer rectifier units can be provided with two alternative modes of output control to suit the project requirements or clients preference. Type I control employs on load tapping switches to provide stepped output adjustment from 10% to 100% of output rating, whilst Type 2 control employs a variable transformer to control stepless output control from 0-100% of the units reacted output. For information purposes, a specification for a typical three phase, oil-cooled transformer rectifier is given below:

The transformer rectifier unit will be of oil-cooled, weatherproof construction suitable for plinth mounting outdoors in a non-hazardous area. The unit will be manufactured for operation from the clients three phase 50 hertz a.c. supply and will be suitable for use in an ambient temperature of up to 50ºC

The transformer rectifier tank will be fabricated from

Typical specification for Wilson TaylorAsia Pacific Transformer Rectifier

Typical specification for Wilson TaylorAsia Pacific Transformer Rectifier

heavy gauge sheet of welded construction and will be fitted with a heavy duty steel skid underbase suitable for plinth mounting. A separate housing will be provided to contain all output terminals, controls and meters, and will be fitted with a hinged, and lockable door with meter viewing.

A.C. Input: 3 phase 50 hertz (voltage to be specified)D.C. Output: amps & volts.Rating: continuousExternal coating: The external tank surface willbe sand blasted. zinc sprayed, primed and undercoated prior to application of the finishing coat of dark grey gloss shade.(Alternative surface preparation and coating specifications can be provided if required)

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The transformer rectifier will be supplied complete with the following fittings and major components:

I a.c. supply circuit breaker or switch fuseI removable gland plate for incoming supplyI incoming supply pilot lightI three phase transformerI three phase silicon diode rectifier with surge protection circuits, or a selenium rectifier stackType I or Type 2 output adjustment control as requiredI set of fused positive d.c. terminalsI set of unfused negative d.c. terminalsI d.c. moving coil voltmeter to indicate output voltageI voltmeter protection fuse.I d.c. moving coil ammeter to indicate total output current

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Technical Information

Major Components and Accessories


Alternative Power Sources

The d.c. meters, terminals, fuses and output control switches will be above oil level.

advantage of an automatically controlled transformer rectifier unit is that it always operates at the lowest possible output required to maintain full protection of the structure and therefore does not use unecessary a.c. power; and will not cause damage to any structure coating by over protection. Manually controlled systems must be adjusted regularly to avoid these problem, plus the equal problems of under-protection.

In areas where suitable a.c. power supplies are not available, but where impressed current cathodic protection is required, Wilson Taylor Asia Pacific is able to provide various alternative power sources. The various options available are listed below, and Wilson Taylor Asia Pacific can provide further information on request.

In addition, the unit will be supplied complete with the first filling of transformer oil and one set of spare fuses and pilot bulbs suitable for two years operation.

In addition to the typical accessories shown above, Wilson Taylor Asia Pacific can provide optional parts to suit the clients own requirements. Typical accessories previously requested are:

In addition to the range of manually controlled options, Wilson Taylor Asia Pacific can supply transformer rectifier units with automatically controlled output facilities. These units must be used in conjunction with a permanent reference electrode mounted on the structure. The permanent electrode monitors the degree of protection being achieved on the structure and this information is relayed to the control circuits within the transformer rectifier unit. The signal from the reference electrode is compared with a preset signal within the control circuits, and the output of the transformer rectifier is automatically increased or decreased as necessary to maintain the potential signal measured by the electrode(s) within -+20mV of the preset signal. The preset signal is adjustable and will be set to the desired level by Wilson Taylor Asia Pacific engineer during commissioning.

Automatically controlled unitsare ideally suited to applications where the environment and electrolyte resistivity are constantly changing, as with sea-going vessels, or in situations where workloads do not allow the clients personnel time to carry out regular potential testing and adjustment of system output. One further

The following accessories will be fitted to the external tank surface.

I thermometer pocket or dial type thermometerI oil filling plugI oil level sight gaugeI oil drain plug or stop cockI silica-gel breather assemblyI d.c. cable gland plate with glandsI rating and identification plate

abcdefg

Optional Accessories

Sun shadesOn-off timersAdditional switching and shunts to allowmeasurement of individual output circuit currentsYale type locks, instead of padlockAdditional smoothing circuits and lightning protectiondevices

Wilson Taylor Asia Pacific transformer rectifier withdiesel generator power supplyThermo-electric generator sets for cathodicprotectionSolar panel cathodic protection power sources

1

2

3

Automatic Output ControlHullmatic



Wilson Taylor Asia Pacific magnesium anodes are cast in two types of alloy, high potential (HP) and low potential (LP), and are available in a wide range. The electrical characteristics of the two alloys supplied by Wilson Taylor Asia Pacific are as follows:

These alloys are generally utilised for the following applications:

abc

abc

Capacity: 1230 amp. hrs/kgConsumption: 7.12kg/amp. yearPotential: -1.70 volts with reference to a silver/ silver chloride (Ag/AgCl) half cell

Capacity: 1230 amp. hrs/kgConsumption: 7.12kg/amp. yearPotential: 1.50 volts with reference to a silver/silver chloride (Ag/AgCl) half cell

Wilson Taylor Asia Pacific MagnesiumAnodes for Cathodic Protection

High Potential Alloy

Low Potential Alloy

Low Potential Alloy (LP)

This alloy is suitable for the temporary protection of ships hulls during fitting out or laying up periods in sea water, estuary water and river waters.

Low potential alloy can also be utilized for protection of buried pipelines, storage tanks and other buried steel structures in high resistivity environments. This alloy is a general purpose type and can be used for the protection of steel structures where the electrolyte resistivity is between 25 to 4000 ohm centimeters.

High Potential Alloy (LP)

This alloy can be used for the same applications as the low potential alloy, but due to its higher potential (driving voltage) will provide a higher current output for a specific anode size.

The higher output capability of this alloy makes it more suitable than the LP alloy in very high electrolyte resistivities and for applications where higher current output is required from anodes of restricted dimensions.

The HP alloy can be utilized for applications when the electrolyte resistivity exceeds 4,000 ohm centimeters.

When enquiring about, or ordering magnesium anodes, please specify the type of alloy required in addition to the Wilson Taylor Asia Pacific anode reference number.

Where magnesium anodes are used for the protection of structures buried in soil it is normal to position the anode within a column of low resistivity, rapid wetting backfill to retain moisture and reduce the resistance between the anode and the soil. For ease of handling and installation, anodes for use in soil can be provided as packaged units within a permeable cloth bag containing a suitable gypsum bentonite backfill of the following composition.

Where magnesium anodes are supplied as part of a complete Wilson Taylor Asia Pacific cathodic protection system, the most suitable of the two alloys will be specified by our engineers.

Pre-Packaged Anodes

All magnesium pipeline anodes are supplied complete with factory connected and sealed cable tails 3 meters

2long 2.5mm PVC insulated stranded copper conductors. Alternative cable sizes and types can be provided on request.

Anode Cable Tails

Wilson Taylor Asia Pacific magnesium anodes are available in the following standard sizes and types. Should the desired anodes not be shown here, Wilson Taylor Asia Pacific may be able to supply alternative configurations in accordance with your requirements dependant on the size and quantity of anodes required.

Standard Anode Range

Power Gypsum 75%Granular Bentonite 20%Sodium Sulphate 5%

MAGNESIUM ANODES

Wilson Taylor Asia Pacific is able to supply magnesium ribbon anodes which are magnesium extruded around a continuous steel core. This type of anode is semi-flexible and is capable of providing a current output of between 3-7 times greater than a cast magnesium anode of the same weight. The magnesium ribbon is available in only a high potential alloy and its characteristics are as follows:

Magnesium Ribbon

Electrical Characteristics

Capacity: 1230 amp. hrs/kg

Consumption: 7.12 kg/amp. year

Potential: -1.70 volts with reference to a silver/silver chloride (Ag/AgCI) half cell

a

b

c

This material has many applications including the descaling of ships ballast tanks and the protection of steel structures buried or immersed in high resistivity electrolytes. Magnesium ribbon provides even current distribution to the structure and in certain cases can be buried in the same trench with the pipeline it is protecting.

Other characteristics of Magnesium Ribbon:

In addition to the standard range of magnesium anodes shown in the preceeding page, Wilson Taylor Asia Pacific is able to supply certain types of anodes for special applications. The most common of these special anodes are listed below:

Other Magnesium Anodes

Type WTM330

Type WTM445

Nominal weight per metre: 0.28kg.Capacity per metre:app. 340 amp. hrsCore diameter: 3mm approx.

Nominal weight per metre: 0.37kg.Capacity per metre:app. 450 amp. hrsCore diameter: 3mm approx.

Storage tank anodes

Domestic hot water tank anodes

Gas pipeline anodes

Condenser water box anodes

These anodes are available with various steel care configurations or fixing clamps.


ALUMINIUM ALLOY ANODE ALALLOY III & WILSON TAYLOR ALLOY III

Characteristics

Materials

Product Range

Alalloy anodes are suitable for a wide variety of applications including the hulls and tanks of ships, fixed off-shore structure, semi submersible, pipelines and jetties.

The standard range of Alalloy anodes is listed overleaf. However, Wilson Taylor Asia Pacific specializes in designing and producing anodes to meet any individual requirement and make their own moulds to do so.Thereby they ensure both the optimum solution to each problem and total control over the quality of the finished anodes.

Alloy anodes are cast from special aluminium alloys developed by Wilson Taylor Asia Pacific. Suitably formulated for specific application, they are characterized by light weight, smooth corrosion pattern, high electrical capacity and stability. Fewer anodes may be used for a given installation compared with other materials and a substantially lower cost per installed system is achieved. Flexible Alalloy anode is extruded onto a mild steel core wire from a special patented aluminium alloy. The flexibility and light weight of this extruded anode, together with the method of clamping, permits its use in applications where the use of cast block anodes may be difficult or uneconomic.

Different alloy formulations are available specially designed for different applications. Alalloy anodes are cast in alloys of aluminium and indium plus additions and have been developed specially for use in sea-water. The materials are very stable in driving potential and efficiency even in electrolytes of varying conductivity and temperature. In normal sea-water, having receptivity of about 25 ohm cm, approximately 2700 ampere hours of current are provided by each kilogram of alloy which will maintain a potential of 1100mV when measured against a silver/silver chloride reference half cell.

Applications

WILSON TAYLOR ASIA PACIFICALALLOY ALUMINIUM


( WILSON TAYLOR ANODES ARE QUALIFIED ACCORDING TODNV-RP-B401 LONG TERM TESTING BY DNV NORWAY)

WILSON TAYLOR ASIA PACIFIC IN-HOUSE QA/QC CAPABILITY


Zinc Alloy Anode (Zincalloy)

Characteristics

Zincalloy anodes are cast to U.S. Military specifications U.S. MIL A-18001K and yield 780 amphere hours per kilogram of alloy with a solution potential of - 1050 m V as measured against a silver/silver chloride reference cell.

Zincalloy anodes are cast from high grade zincalloy to ensure an even corrosion pattern, reliable electrical efficiency and long working life.

Materials

The standard Wilson Taylor Asia Pacific range of zincalloy anodes is listed overleaf. However has the facility of designing and producing anodes to meet any individual requirement and make their own moulds to do so. Thereby, they ensure both the optimum solution to any particular problem and total control over the quality of the finished anodes.


Zincalloy anodes are particularly suitable for ballast tanks and hull of ships, jetties and subsea pipeline applications in bracelet configuration. Zincalloy anode is not suitable in high temperature environment of 50ºC and above.

Product Range

Applications

ChemicalComposition

ElectrochemicalProperties

The specification demands stringent analytical control and Wilson Taylor Asia Pacific, with number of casting facilities throughout the world, use the very latest analysis and quality control techniques to produce products of a consistently high standard.

Nominal Potential:-1.05 V,Ag/AgCI

Nominal Capacity: 780 Amphere hours per kg

ZINC “ZINCALLOY” ANODES


ENGINEERING SERVICES &CONSULTANCY

Engineering Services

Wilson Taylor Asia Pacific can provide all necessary field services required in respect of cathodic protection. These include the following:

Wilson Taylor Asia Pacific and associates are able to provide the following services either as part of a turnkey project, or separately to suit clients requirements. These services are provided using Wilson Taylor Asia Pacific experienced engineers and technicians and are available worldwide.

Field Surveys

Wilson Taylor Asia Pacific will undertake all necessary design and consultancy responsibilities for any cathodic protection project. The extent of these services can be adapted to suit clients requirements. For example:

Design Consultancy

Wilson Taylor Asia Pacific can provide skilled teams of personnel to carry out all necessary cathodic protection installation and maintenance work. Full details of these services can only be provided on receipt of clients requirements, but typical examples would be:

Installation and Maintenance

Where it is intended that all necessary testing, adjustment and maintenance of a cathodic protection system be carried out by the clients' own personnel on site, Wilson Taylor Asia Pacific can provide comprehensive training in all these vital functions to ensure satisfactory continued operation of the system after handover or system repair by Wilson Taylor Asia Pacific .

Wilson Taylor Asia Pacific cathodic protection systems are provided with sets of system log sheet after completion by clients personnel on site. These log sheets have columns for potential voltage readings, transformer rectifier output voltages and currents, transformer rectifier control positions and other useful information. These logs should be compiled on a regular basis and a copy returned to Wilson Taylor Asia Pacific office for analysis and comment regarding any necessary adjustments or additional testing required. This service is provided on a free of charge basis where Wilson Taylor Asia Pacific have supplied and installed a complete cathodic protection system but can also be extended to cover systems where Wilson Taylor Asia Pacific have carried out major repair or reinstatement, or where maintenance or training services have been provided.

In addition to complete turnkey services covering design, supply, installation, testing and commissioning of cathodic protection systems, and the provision of equipment to clients specifications, Wilson Taylor Asia Pacific has the ability to provide assistance in respect of other cathodic protection problems. If clients requirements are not covered, please send details to Wilson Taylor Asia Pacific office for assistance.

Training of Clients Personnel

Analysis of System Performance

Other Services

Site surveys to determine soil of other electrolyteresistivities and to assess the elements effectingthe design of a cathodic protection system fora new project.Site surveys to carry out current drainage testsand to assess any other factors effecting design ofa cathodic protection system for an existingstructure.Site surveys to assess the performance of existingcathodic protection systems and determine anynecessary repairs, improvements and maintenancerequired to ensure continued satisfactoryoperation.

a

b

c

Design and consultancy services for a cathodicprotection scheme including all necessary fieldsurveys and preparation of drawings andspecifications for issue to tenderers.Assessment of tenders, assuring conformity ofproposed equipment with specifications anddrawings, and providing supervision of installation,testing and commissioning on site.Engineering consultancy for assessment of design,conformity to specifications and drawings,supervisory services on site.As independent inspector representing owners,inspection of equipment supplied by others.

a

b

c

d

Installation of sacrificial anodes or otherreplacement cathodic protection equipment andmaterial.

a

Annual maintenance of cathodic protectionsystems including all necessary testing, adjustmentand maintenance and provision of major repairs andrecommendations.

c

Provision of all necessary plant, labour, equipmentmarine transportation and supervisory services tocarry out major repairs and reinstatement of existingcathodic protection systems.

d

Installation of additional cathodic protectionequipment and material to expand an existingcathodic protection system.

b


To enable the corrosion engineer to design the most suitable cathodic protection system for a particular project. Our engineer must be present with adequate knowledge of the nature of the structure and the surrounding electrolyte. In addition he must take many other factors into consideration that will effect the system design parameters, such as the type and condition of any protective coating and required life of the cathodic protection system.

Design of Suitable CathodicProtection Systems

Without access to all relative information it is necessary for the engineer to make assumptions based on previous experience and the correctness of the design cannot be confirmed until the commissioning of the installed system. At this stage, any improvements to system performance might prove costly and difficult to accomplish. Obviously, with this knowledge in mind, it would be natural for the engineer to base all assumptions on the worst possible circumstances to ensure that the installed system will perform satisfactorily. This would result in a system with a much higher capacity, and probably more test and adjustment facilities than the engineer would have proposed had he been provided with sufficient information.

Wilson Taylor Asia Pacific will always provide the most suitable and economic cathodic protection system for any application. To achieve this aim it is necessary for their engineers to have access to all relevant available information.

Wilson Taylor Asia Pacific will be pleased to provide proposals in respect of complete cathodic protection systems.


CATHODIC PROTECTION SYSTEM AUDITS

Cathodic Protected pipelines require System Audit to evaluate the performance of the installed CP system. Wilson Taylor carried out CP System Audit in accordance to International Standard NACE, BS and DNV. Some of the methods offered by Wilson Taylor Asia Pacific as follows;

Pipeline Current Mapping (PCM) is relatively new technology in locating faults and poor coating that is draining CP Currents, resulting in pipelines not adequately protected by its CP system.

The PCM advantage over traditional DCVG Survey is mainly on its ability to conduct survey for pipelines buried under Concrete and Road Surface. It detects accurately the location of faults when conducted by highly trained operators. The PCM machine also comes with A-Frame which can be used to perform CIPS Survey.

Close Interval Potential Survey (CIPS) is a survey technique that provides a detailed continuous pipe to soil potential profile. In normal operation, Pipe to Soil Potentials measured only at test points. When measuring a potential at one location (test point), the amount of pipe sampled in the measurement is considered the length of the pipe encompassed by a 120° arc entered on the reference electrode. To determine the potential over the entire pipeline surface require that the reference electrode be moved along the centerline of the pipe route and place at regular intervals (@ every 2m). The purpose of a Close Interval Potential Survey (CIPS) is to evaluate the criteria of the cathodic protection, to identi fy local deficiencies in a cathodic protection system, to assist in identifying the causes of such deficiencies, and to aid in determining the requirements to enhance the level of cathodic protection to the structure.

PIPELINE CURRENT MAPPING (PCM)

CLOSE INTERVAL POTENTIAL SURVEY (CIPS)



Direct Current Voltage Gradient (DCVG) Survey is a survey technique to evaluate the coating condition on buried pipelines. The principle of this technique involves detecting a voltage difference on the earth surface just above the buried pipeline by using two or more portable reference electrodes separated by a short distance. In a DCVG Survey, a DC Signal is typically created by interrupting the pipeline's Cathodic Protection current, and the voltage gradient in the soil above the pipeline is measured. Voltage gradients arise as a result of current pickup/discharge at coating defect locations.

Soil resistivity influences the degree of corrosion of buried metals and also partly determines the design configurations of cathodic corrosion protection system.

Soil resistivity measurement is normally conducted using Wenner 4-pin Method. Developed by American National Bureau of Standards, this specify insertion of four pins into the ground at even spacing and in a straight line. The two outer pins are current electrodes and the two inner pins are potential electrodes, which measure the potential drop due to the resistance of the soil path when an alternating current is passed between the outer pins.

The resistance can be measured and the resistivity calculated according to the formula. It should be noted that measurements made in this manner indicate average resistivity over a depth of soil corresponding to the spacing between adjacent pins

DIRECT CURRENT VOLTAGE GRADIENT (DCVG) SURVEY

SOIL RESISTIVITY SURVEY

Wilson Taylor Asia Pacific has the capability and experienced NACE Certified CP Engineers to perform FEED works in relation to new projects and rehabilitation to meet client's specifications.

Stray Alternating Current (AC) on buried pipeline structures is a safety concern, and at high AC current densities, corrosion can also be a concern. Any person coming in contact with a structure that may have a hazardous AC voltage must be aware of these hazards and the safety precautions that need to be taken care off.

There are three couplings termed “Capacitive”, “Inductive” and “Conductive” which can cause an AC induced voltage on the buried pipeline which is in parallel/crossing with the high transmission electric power line. These problems can be investigated, studied and mitigated.

FEED – FRONT END ENGINEERING DESIGN

AC MITIGATION SURVEY


CATHODIC PROTECTION MATERIALS

Wilson Taylor Asia Pacific is able to provide an extensive range of accessories for the installation, testing and commissioning of cathodic protection systems.

These accessories can be supplied separately, or are incorporated into complete Wilson Taylor Asia Pacific systems.

Wilson Taylor Asia Pacific Accessoriesfor Cathodic Protection Systems

Backfill is high quality calcined coke breeze with a maximum of 15% fine. This material has a bulk density of approx 725 kgs per cubic metre, and a maximum resistance of 50 ohm/cm. Suitable for shallow vertical and horizontal ground beds.

Grade A

Backfill is high quality calcined petroleum coke granules. This material has a bulk density of approx 1188 kgs per cubic metre and a resistance of 0.1 ohm.cm. Suitable for shallow vertical and horizontal ground beds and may also be used in deepwell ground beds.

Grade B

Wilson Taylor Asia Pacific can provide flange insulating gasket sets or monolithic insulating joints to suit all pipelines. Brief details are as follows:

Insulating Joints & Kits

These kits contain one flange insulating gasket together with insulating sleeves and washers for the flange bolts. Replacement insulating sleeves and washers can be provided separately if required.

For further information please contact Wilson Taylor Asia Pacific and advise the following details:

Flange Insulating Kits

Wilson Taylor Asia Pacific can supply a range of permanent reference cells for use with automatically controlled impressed current systems, or for ease of potential monitoring on manually controlled or sacrificial anode systems. The types available are:

Permanent Reference Electrodes

Portable Reference CellsFor use during testing, adjustment and commissioning

of impressed current and sacrificial anode cathodic protection systems, Wilson Taylor Asia Pacific is able to provide a range of standard portable reference cells.

Portable Silver/Silver Chloride HalfCell

These are prefabricated, non separable joints supplied ready for welding into the pipe. In the smaller diameters, alternative threaded joints are available for easier installation.

Monolithic Insulating Joints

The performance of monolithic isolating joints is superior to that of a flange isolating kit in that mechanical strength and high electrical resistance are retained throughout the life of the pipeline, without the need to carry out inspection and maintenance.

Additional information in respect of Wilson Taylor Asia Pacific permanent reference electrodes can be provided up on request.

Backfill is high quality pumping grade calcined petroleum coke granules with added carbon lubricants and wetting agents to assist fluidising. This material has a bulk density of 1188 kgs per cubic metre and a resistance of 0.1 ohm/cm. This grade is specifically for deepwell ground bed installations.

Grade C

Nominal pipe size and specification of flange(ASTM etc)Maximum operating pressure and temperature ofpipeProduct carried by pipe

a

b

c

a Silver/Silver Chloride (Ag/AgCI)Marine Reference Electrode

This type of cell is designed to provide accurate

b Zinc Marine Reference Electrode(Zn)

c Copper/Copper Sulphate(Cu/CuSO4)Onshore Reference Electrode

For permanent mounting, below water level, onall marine systems. Suitable mounting arrangementare available for all applications. The Wilson TaylorAsia Pacific permanent Ag/AgCI reference electrodeis fitted with a factory connected and encapsulatedcable tail.

For permanent mounting, below water level on allmarine systems. Suitable mounting arrangementsare available, and the reference electrode issupplied complete with factory connected andencapsulated cable tail.

This is the accepted standard cell for measurementof structure potentials on land installations and issuitable for permanent underground installation.Under most resistivity conditions the electrodecan be installed as supplied in its semi-permeablehousing, but for extreme high resistivity conditions,Wilson Taylor Asia Pacific supply an alternative cellcontained within a cloth bag surrounded by tworesistivity backfills.


Designed specifically to measure the potential of land based buried structures, this unit is used in conjunction with any high resistance voltmeter. Prior to use, the supplied copper sulphate crystals must be dissolved in distilled water until a saturated solution is obtained. Two versions of this cell are available, one with factory connected cable tail of your requested length and the second with simple connection point for use with any type of cable.

Portable Copper/Copper SulphateHalf Cell

A general purpose unit suitable for measurement of structural potentials in aqueous solutions or low resistivity soils. No preparation of this cell is required prior to use but readings must be referred to the supplied monogram if comparisons between equivalent Ag/AgCI and Cu/CuSO4 potentials are required for any given electrolyte resistivity.

Portable Zinc Reference Cell

Wilson Taylor Asia Pacific can supply a wide range of portable cathodic protection test equipment and other instruments either separately or as part of a complete system. Further information in respect of the following equipment is available up on request.

Portable Test Equipment andCorrosion Multimeters

measurement of structure potentials in aqueous environments when used in conjunction with a suitable high resistance voltmeter.

Wilson Taylor Asia Pacific can provide high quality accessories for the installations of impressed current cathodic protection systems. The following items are supplied as part of a complete Wilson Taylor Asia Pacific system but can be provided separately if required, by sending full details and specifications with your enquiry.

Ancillary Equipment for ImpressedCurrent Systems

Single or multi-sore cables with stranded copper conductors, available with a wide variety of insulations, sheath and armouring options. PE/PVC, Haler, HMWPE, AXPE/PVC and others upon request.

Cables

A wide range of boxes can be supplied including coated or galvanised steel and cast iron, die cast aluminium, stainless steel and non-metallic types. Suitable boxes and enclosures can be provided for installation in all areas ranging from non-hazardous to Division One classification and can be supplied with or without the necessary cable glands.

Junction Boxes & Enclosures

Wilson Taylor Asia Pacific will manufacture suitable current control and resistance bond boxes against your specifications and can supply these complete with all necessary components, instrumentation and controls, if required.

Current Control & Resistance BondBoxes

Suitable test stations are normally designed and manufactured specifically for each project, although standard concrete test posts are also available. For further informations please advise the quantity of terminals and functions together with the typical test station requirement eg above ground, surface mounting, etc.

Cathodic Protection Test Stations

A wide range of kits, containing plastic mould and encapsulation resin, is available for most cable joining and splicing applications. For further information please advise the quantity and sizes of cable to be joined/spliced and confirm if split bolt connectors are also required. For joining two sections of cable, Wilson Taylor Asia Pacific can supply compression ferrule connectors, in place of split bolts, if specified.

Cable Joint & Splicing Kits

Wilson Taylor Asia Pacific can provide all necessary thermit welding equipment including moulds, charges, flint guns and other tools, required for making connection to piipes, rails, rods and flat surfaces. Further details available on request.

Thermit Welding Equipment

If you require any item of cathodic protection equipment not listed in this catalogue, including ancillary parts such as cable glands, cable lugs, encapsulation resins, cable cleats, conduit etc., Wilson Taylor Asia Pacific would be pleased to offer suitable items on receipt of your detailed specifications and drawings where applicable.

Other Items of Equipment

The cell is supplied with a standard 10 meter length of cable, but can be provided with alternative lengths on request.

The cell must be soaked in saline water for 24 hours prior to use.

This reference cell can be used in conjunction with any high resistance voltmeter. Wilson Taylor Asia Pacific can provide further information on their portable reference cells upon request.

Digital & analogue potential voltmetersDigital & analogue corrosion multimetersSoil resistivity test sets (4 pin Wenner method)Conductivity cells for water resistivity measurementcurrent interruptersSoil resistivity metersPipe, cable and re-bar locators


ER Coupon for CP Verification

Specialised for the detection of corrosion influenced by AC/DC stray current

Date: Jan. 19th - Feb. 15th 2004

Description: Coupon B test post km 45.78

Technician: MetriCorr

0

50

100

150

200

250

300

350

15/01/2005 22/01/2005 29/01/2005 05/02/2005 12/02/2005 19/02/2005

Vco

rr-

mym

/yr

Corrosion Rate

ER View

Time - Date

To be buried along pipelines for control of catholic protection effectiveness.

Quantifies corrosion in addition to all traditional coupon measurements.

Continuous logging with MetriCorr automated coupon reader, or

Spotwise readings giving degree of accumulated corrosion.

Various shapes and size of artificial coating defects

Easy positioning in the soil.

The MetriCorr ER coupon must be electrically connected to the pipeline and placed in the desired depth and position - just like any other coupon.

Use it with MetriCorr ICL-02 or ACD-03 or an equivalent automated coupon reader to collect DC potential, AC voltage, AC and DC current density.

On top of this, the corrosion condition can be assessed by spotwise measurements, or the time stamped corrosion rate can be measured and correlated to the electrical fingerprints of the coupon collected with the MetriCorr Interference Corrosion Logger Dataloggers - see separate information sheets.

The coupon is designed as an electrical resistance (ER) probe with an exposed coupon element and a shielded reference element. The electrical resistance of the elements are measured, hence by simple mathematical algorithms the resistance data are correlated with element dimensions and it yields the residual thickness of the element.

Make use of the MetriCorr ER coupon either along with traditional spotwise multimeter measurements or make use of the MetriCorr dataloggers, which can be arranged in a test post. Communication with dataloggers are made either by the RS 232 interface of your PC or remotely.

SPECIALIZED PRODUCTS - ER PROBE


CHINAWilson Taylor Trading (Shanghai) Limited

Room 2002 Dragon Pearl Complex, 2123 Pudong Avenue, Shanghai 200135, China.

Tel: +86 (21) 5821 5157 Fax: +86 (21) 6853 8055E-mail: [email protected]

CHINAWilson Taylor Trading (Shanghai) Limited

Room 2002 Dragon Pearl Complex, 2123 Pudong Avenue, Shanghai 200135, China.

Tel: +86 (21) 5821 5157 Fax: +86 (21) 6853 8055E-mail: [email protected]

AGENT / DISTRIBUTOR :

HONG KONGWilson Taylor Far East Ltd

Room 601 Grand City Plaza Tsuen Wan New Territories, Hong Kong.

Tel: (852) 3118 6108 / 6128 Fax: (852) 3118 6111E-mail: [email protected]

SINGAPOREWilson Taylor Asia Pacific Pte Ltd

1, Jalan Samulun, Singapore 629119 Tel: (65) 6264 0388 Fax: (65) 6264 1806

E-mail: [email protected]: www.wilsontaylorasiapacific.com

INDONESIAWilson Taylor Asia Pacific Pte Ltd

Representative Office Jl. Raya Narogong Km 12,5 Pangkalan 4

Cikiwul RT.01/RW.06 No. 3, Bantar GebangBekasi 17310, Indonesia

INDONESIAWilson Taylor Asia Pacific Pte Ltd

Representative Office Jl. Raya Narogong Km 12,5 Pangkalan 4

Cikiwul RT.01/RW.06 No. 3, Bantar GebangBekasi 17310, Indonesia

Industrial Book 1 - Seridamai• Cathodic protection cable - XLPE/PVC, HMWPE, HALAR, Armoured,...

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Transcript of Industrial Book 1 - Seridamai• Cathodic protection cable - XLPE/PVC, HMWPE, HALAR, Armoured,...