Cte Ongc Spec

8/3/2019 Cte Ongc Spec

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SPECIFICATION FOR

COALTAR ENAMEL

COATING OF SUBMARINE

PIPELINE

SHEET NO.

1 OF 21

SPECIFICATION FOR

COALTAR ENAMEL COATING

OF SUBMARINE PIPELINES

OIL AND NATURAL GAS CORPORATION LTD.

INDIA

ISSUED FOR BID 21 0

BY APPROVED REMARKS NO. OF

PAGES

DATE REV.


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CONTENTS

SECTION TITLE

1.0 SCOPE

2.0 REFERENCE DOCUMENTS

3.0 GENERAL REQUIREMENTS

4.0 MATERIALS

5.0 SURFACE PREPARATION

6.0 PRIMING

7.0 HEATING OF ENAMEL

8.0 COATING OF PIPES

9.0 INSPECTION

10.0 REPAIRS

11.0 MEASUREMENT AND LOGGING

12.0 HANDLING AND HAULING OF PIPES

13.0 DOCUMENTATION


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1.0 SCOPE

This specification governs the minimum requirements of materials,

equipment, application, inspection, repair, handling and other aspects of

external corrosion protection coating of offshore pipelines using glass

fiber reinforced coal tar enamel coating system. The work includes the

furnishing of all labour, materials, tools and equipment and the

performance of all operations and incidentals necessary for the coating,

handling, storing and shipping of bare and coated pipes.

Contractor shall obtain Companys written approval for any deviations

from the requirements of this specification, and/or the standard referred

herein.

This document is not intended to be all inclusive, and the use of the

guidelines set forth does not relieve the Contractor of his responsibility to

supply a product capable of performing its intended service.

2.0 REFERENCE DOCUMENTS

The following documents (latest revision or as specified) are referred inthis specification and are a part of this specification. In case of conflict

between reference standards or specifications the more stringent shall

apply. In case of conflict between this specification and the reference

documents, this specification shall apply.

a. BS 4164-1987 : Coal Tar Based Hot Applied

Coating Materials for protecting

Iron and Steel including suitable

primer.

b. AWWA C 203-86 : Coal Tar Protective Coating

Pipelines - Enamel and Lining for

Steel Water Pipelines Enamel

and Tape Hot Applied.

c. SSPC-SP 1 : Structural Steel Painting Council

Solvent Cleaning.


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d. SSPC-SP 10 : Structural Steel Painting Council

Near White Blast Cleaning

e. API RP 5L 1 : Recommended Practice for Rail

Road Transportation of Line Pipe

f. API RP 5L 5 : Recommended Practice for Marine

Transportation of Line Pipe

g. SIS 055900 : Pictorial Surface Preparation

Standards for Painting Steel

Structures.

3.0 GENERAL REQUIREMENTS

3.1 The Contractor shall perform all work in accordance with this

specification and other requirements noted.

Contractor shall submit a detailed written description in the form of a

manual covering coating equipment, procedure, materials, inspection, testsand repair etc. for Company approval.

3.2 The Contractor shall provide the skilled personnel required for execution

of this work. The equipment required shall be in good operating

condition. Improvised equipment shall not be acceptable.

3.3 The Contractor shall supply all coating materials required by this

specification and shall carry out tests on one sample per batch of supply as

described subsequently in this specification in Section 4.0.

The tests shall be carried out by the Contractor at his yard and the results

shall be reported to the Company for approval and acceptance.

If the Contractor does not have adequate facilities at the yard to carry out

these tests, the same shall be got done at a Company approved

independent laboratory.


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3.4 The Contractor shall unload the pipes at the coating plant, tally, store and

provide security for the pipes during coating and storage. The Contractor

shall be responsible for placement of the bare and coated pipes in storage

in accordance with the reference specifications.

3.5 All coating and wrapping operations shall be performed under the

supervision of and performed by, personnel skilled in the application of

the coating system. Inspection of the coating and wrapping of the pipes

shall be performed by qualified inspectors. The qualification of the

inspectors shall be verified and approved by the Companys

Representative prior to the start of work. Final acceptance of all coating

works shall be determined by the Companys Representative.

3.6 The Contractor shall provide access, during all phases of work, to the

Company and Companys Representatives/inspectors. Any expense

caused by the Company inspector stopping the work because it is not

being carried out as per this specification shall be borne by Contractor.

3.7 All tools and equipment furnished by the Contractor shall be of good

quality, maintained in good operating condition and suitable for use to

apply materials as per this specification. All equipment shall be subject to

approval by the Company Representative.

All cleaning, priming and coating machines shall be equipped with rubber

or wheels overlaid with hard fiber to prevent marking or denting the pipe.

4.0 MATERIALS

4.1 The primer shall be fast drying synthetic primer for cold application

certified to meet British Standard BS 4164, Section 3.

4.2 Coal Tar Enamel

The coal tar enamel shall consist of a uniform mixture of a specially

modified coal tar and inert non-fibrous filler. The coal tar enamel shall be

Grade 120/5 and shall conform to British Standard BS 4164, Section 4,

except that penetration shall be between 7 and 9 mm when tested at 25

degree C. The material shall be certified by the manufacturer as being

suitable for use of the design temperature of the pipeline.


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4.3 Procurement

The coal tar enamel and Coal Tar Primer shall be obtained from the same

manufacturer. The manufacturer of primer and coal tar enamel shall be

approved by Company prior to procurement of the material.

4.4 Identification

The primer and coal tar enamel containers shall be legibly and

permanently marked as follows:

1. BS 4164 : 1987

2. Primer Description (for Primer Containers) and Grade 120/5 (for coal

tar enamel containers).

3. Manufacturers identity

4. Manufacturers batch number

4.5 Sampling and Testing

All sampling and testing of primer and enamel shall conform to BS 4164,Section 7. The manufacturers test certificates for each characteristic of

primer and coal tar enamel as per BS 4164 shall be furnished for each

batch of primer and coal tar enamel.

4.6 Wrapper

4.6.1 Inner Wrap

The inner wrap glass fiber reinforcement shall conform to AWWA C 203-

86, Appendix Section A.2, except that minimum thickness shall be 0.5

mm. The glass fiber reinforcement material shall be reinforced in thelongitudinal direction.

4.6.2 Outer Wrap

The outer wrap material shall be coal tar impregnated glass fiber wrap and

shall conform to the requirements of AWWA C 203-86, Section 2.10.


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4.7 White Wash

The white wash used as a final coat shall be manufactured in accordance

with the White Wash Formula as specified in AWWA C 203-86,

Section 2.11.

4.8 Approvals

4.8.1 Prior to start of work, Contractor shall submit manufacturers test

certificate of all raw materials for each batch as per applicable material

standard and this specification. In case of coal tar impregnated outer

wrap, the manufacturers test certificate shall also include the test

certificates of the base glass fiber wraps used for impregnation.

4.8.2 Contractor shall perform the following tests at his coating yard or in a

Company approved test laboratory, for each batch of the raw materials and

obtain Company approval prior to using these materials for coating

application:

4.8.2.1 Coal Tar Enamel

i. Softening point (Ring and ball test)

ii. Penetration

iii. Filler content by ignition

iv. Peel

v. Cathodic Disbondment (Frequency : one at start of production and one

in mid production)

vi. Impact Resistance (Frequency same as for (v) above)

4.8.2.2 Inner Wrap

i. Weight

ii. Thicknessiii. Elmandorf Tear Strength

iv. Breaking Strength

4.8.2.3 Outer Wrap

Coal tar impregnated glass fiber outer wrap


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i. Weight

ii. Thickness

iii. Breaking Strength

4.9 Storage and Handling of Coating Materials

Primer, rolls of inner and outer wrap shall be kept in the Contractors

warehouse and only the daily requirements withdrawn at one time. Primer

containers shall be kept closed in order to prevent entrance of dirt, water

or other contaminants or loss of solvent.

Coating and wrapping materials shall be handled in such manner as to

prevent injury to packages. All rolls of inner and outer wrap shall be

stored in a dry place, kept away from contact with concrete flooring and

protected from the weather.

All rolls or wrappers shall be carefully handled in order to prevent

contamination or distortion of rolls and damage to the edges which may

interfere with efficient application. Any such materials which in the

opinion of the Companys Representative show evidence of deteriorationshall be rejected and shall be replaced by the Contractor at his own

expenses.

5.0 SURFACE PREPARATION

5.1 The procedure for cleaning of pipes shall be approved by the Companys

Representative prior to being used.

5.2 All oil grease or other contaminants shall be removed by solvent cleaning

in accordance with SSPC SPI prior to shot/grit blasting. All exterior

surfaces of the pipe shall be blast cleaned to near white metal finish toSwedish Standard SIS 055900 Grade SA 2-1/2. Weld end bevels shall be

protected at all times during the entire coating operation.

5.3 The abrasive blast material shall be free of impurities, inclusions, water

and oil. All abrasives shall be removed by brush off, blast or vacuum type

cleaner prior to applying primer.


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5.4 The compressed air for blasting shall be free of water and oil. Separators

and traps shall be provided at the compressor and blasting station.

Separators and traps shall be checked daily for effective moisture and oil

removal during coating operations.

5.5 Blast cleaning operation shall not be conducted on surfaces that are less

than 3C above dew point or when the relative humidity is greater than 90

percent, unless preheating of the pipe is performed. Blast cleaning under

these conditions may be performed providing the pipe can be warmed to a

temperature (not exceeding 52C) sufficient to perform the blastingoperations.

5.6 Prior to primer application, the pipe shall be cleaned to remove any

wetness or other contamination.

5.7 Care shall be taken that no grit remains inside the pipe. Laminations or

other irregularities on the steel surface that become visible after blast

cleaning shall cause the pipe to be rejected unless in the opinion of the

Companys Representative, it can be accepted by grinding and reblasting.

Such repairs shall be carried out by Contractor at no extra cost to the

Company.

6.0 PRIMING

6.1 Primer shall be kept at a warehouse and only the daily requirements shall

be brought to the job site. Primer shall be thoroughly agitated in its

container before use. Only the amount of primer required for immediate

use shall be emptied from the drums into open containers. After obtaining

the quantity required, bungs shall be immediately replaced to prevent the

loss of solvents by evaporation. Primer which has become contaminated

with foreign matter or has thickened because of evaporation of solvents

shall not be used. The Primer shall be cold applied to a clean, dry surface,

immediately after surface preparation operation.

6.2 The primer shall be applied as received from the manufacturer unless, in

the opinion of Companys Representative, a thinner should be added to

speed up the drying time. The thinner, when used, shall be mixed with the

primer in the manner and proportions recommended by the manufacturer

of the primer.


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6.3 Primer shall be applied with pneumatic spray gun, at a rate recommended

by the manufacturer on new pipe in a uniformly thin film free from runs,

drips, bubbles, sags, dust, grease or foreign matter. Primer shall

completely cover the circumference of the pipe and all surfaces which are

to be coated.

All missed spots or areas covered with insufficient primer shall be touched

up immediately by hand brushing. Primer which has been applied too

heavily, such as at the base of welds, shall be brushed out before the

primer sets.

The priming coat shall not be applied when the pipe to be primed is wet or

moist.

6.4 During the application of the priming coat, the primer in the container

shall be stirred regularly.

6.5 The freshly primed pipe shall be permitted to dry on racks until it is no

longer wet, sticky or tacky.

Pipes on which the primer, after being applied, becomes contaminated by

dust before it is dry or which becomes dead, shall be reprimed, or if sodirected by the Companys Inspector, shall be recleaned and reprimed. In

no case shall a third application of primer be made without having

removed all the previous coats. The cost of recleaning and repriming shall

be borne by the Contractor.

Dead or crumbly primer can be evaluated by scraping a small quantity

of primer from the top and bottom of pipe and kneading it. Properly dried

primer is easily kneaded and rolled and does not adhere to the skin.

Insufficiently dried primer will stick to the skin and feel tacky. Over-dried

or dead primer will become powdery or crumbly.

6.6 Primer once used shall not be reused either by recycling or otherwise.Removal of primer from the primed pipe due to abrasion from any

metallic contact will be reprimed properly and allowed adequate curing

time before flood coating. The Primer coat shall be exposed for curing,

before flood coating, only within the time limits recommended by the

manufacturer.


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6.7 During or after drying of primer coat, the pipe shall be handled with care.

All reasonable precautions shall be taken to prevent excessive dust

depositing on the primed pipe or on pipe prior to priming by shielding the

pipe or by prohibiting movement of mobile equipment/by watering surface

from where the dust arises.

7.0 HEATING OF ENAMEL

7.1 Preparation

7.1.1 The enamel, prior to being cut, shall have its surface freed from all

contaminations of whatever nature and shall be cut into pieces weighing

approximately 10 kg., on a platform so constructed as to prevent the

introduction of any contaminations during the cutting process. In no case

shall enamel be cut on flattened enamel drums.

7.1.2 The supply of chopped enamel shall be covered with tarpaulin or other

suitable means when there is a danger of wetting or contaminations due to

local conditions.

7.1.3 Enamel shall be delivered to the heating kettles entirely free of allcontaminates including, but not limited to, pieces of metal, wood, grass,

leaves, dirt, sand or gravel.

7.2 Heating

7.2.1 The enamel shall be heated in clean approved kettles provided in sufficient

number to maintain a continuous supply of hot enamel. Kettles shall be of

the mechanically agitated type.

7.2.2 The kettles and patch-pots shall be equipped with fuel oil, kerosene or gas

burners.

7.2.3 Kettles and patch-pots from which enamel is drawn into the coating

machine shall be equipped with strainers (Wire mesh 1.5 mm size) which

will prevent the introduction of, and inclusion in the enamel applied to the

pipe of coke, filler deposits, or other undesirable matter which will

detrimentally affect the application or the properties of the coating. These

strainers shall be located where they can be easily cleaned.


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7.2.4 Each kettle shall be equipped with an accurate, dial type thermometer with

(90-300C) appropriate range. Patch-pots shall be equipped with a dial

thermometer. Thermometers shall be placed on the region of maximum

temperature. In addition, each kettle shall be provided with a temperature

recorder and records from each recorder should be presented to the

Company Representative at the end of each day. All thermometers shall

be checked periodically for accuracy with a long-stem mercury

thermometer or other thermometer of known accuracy.

7.2.5 All kettles and patch-pots shall be carefully cleaned before being charged

each time. All traces of old coatings, cooked deposits, oil and other

foreign matter shall be completely removed.

7.2.6 While heating, flames from the burners shall be kept low until the enamel

on the bottom of the kettle has melted and the agitators have been started.

The flames shall be increased gradually until about one-half of the charge

has been melted. Full heat shall then be applied until the optimum

application temperature has been reached. The burners shall then be

adjusted to maintain the optimum application temperature of the enamel.

Enamel in patch-pots shall be heated with the same care as describedabove.

During the entire time that the enamel is in a molten condition, it shall be

continuously agitated in the kettles or stirred every 15 minutes with steel

paddles in the case of patch-pots. The rate of agitation shall be such as to

prevent separation of filler and formation of coke. Wooden sticks or

paddles shall not be used for stirring.

7.2.7 Kettles lids shall be kept tightly closed at all times, as will patch-pots

lids when enamel is not being stirred.

7.2.8 Enamel heated to temperatures above the maximum specified by themanufacturer for more than 15 minutes or heated for prolonged periods

without agitation and/or with open lids, shall be condemned and dumped.

The cost of this shall be on the Contractors account.


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7.3 Interruption

7.3.1 In the event of an interruption of short shut-down due to weather

conditions or other unavoidable causes, the burner flames shall be

decreased immediately. The temperature of the charge shall be reduced to

approximately 100F less than the application temperature until operation

starts-up again. The kettle lids shall be kept tightly closed during the shut-

down period and the mechanical agitators kept in continuous operation.

Patch-pots not equipped with mechanical agitators shall be emptied.

Kettles and patch-pots shall be emptied at the end of each day or prior to a

long shut-down. The enamel may be drained into suitable containers.

7.3.2 Care shall be exercised to ensure that the enamel in the mechanically

agitated kettles or patch-pots is brought back to the optimum temperature

before application is resumed. Enamel which has been previously heated

to application temperature then drawn from the kettle or patch-pot may be

reheated provided it has been kept clean.

7.3.3 The previously heated enamel shall be chopped again and added to the

new charge with fresh enamel. The contents of the new charge shall not

be more than 10 parts of previously heated enamel to 90 parts of fresh

enamel. Fluxing will not be permitted.

7.3.4 All kettles or patch-pots shall be cleaned whenever coke or other deposits

form on the heating surface.

8.0 COATING OF PIPES

8.1 The coating system shall consist of applying over the primed pipe, a coat

of coal-tar enamel having a minimum thickness of 2.4 mm and one wrap

of glass-fiber mat, followed by a second coat of coal-tar enamel having a

minimum thickness of 2.4 mm and wrap of glass - fiber mat followed

immediately by an outer wrap of coal-tar impregnated glass fiber felt. Theminimum thickness of coating (without the outer wrap) shall be 4.7 mm +

0.5, -0. When the protrusion of weld seam interferes with this thickness,

the thickness of the coating above weld seam shall meet the thickness

specified.

8.2 Enamel shall be applied by pouring on the revolving pipe and spreading to

the specified thicknesses. Enamel shall be applied so that each spiral

resulting from the spreading operations shall overlap the preceding spiral


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producing a continuous unbroken film free from defects, skips or holidays.

Machine operators shall be required to make all necessary adjustment to

ensure a continuous film of enamel without undue loss of temperature of

point of application.

8.3 Defects such as bubbling or foaming caused by improper machine

adjustment shall be cause for shutting down operations until air pockets

have been removed from pumps and supply lines and required coating

shoe adjustment have been completed.

8.4 Coating shoes shall be kept evenly centered on the pipe and shall not be

allowed to drag or thin the enamel below specified thickness at any point

due to improper bridling. Shoes which are out of round or damaged shall

be immediately replaced. Thickness of the coating applied shall be

frequently tested with an approved pit gauge. The coating punctured by

the pit gauge shall be repaired.

8.5 Simultaneously with the first coat of coal tar enamel, glass-fiber mat shall

be mechanically applied in a continuous end-feed machine, or in a lathe

type machine, or by other suitable wrap application equipment. The roll

of glass-fiber mat shall be under tension sufficient to embed the mat in the

enamel before the latter sets or cools. The mat must be placed in the outerthird of the first coat of enamel and not be pulled through the hot enamel

to the metal surface. The second coat of hot coal tar enamel shall then be

applied simultaneously with the second layer of glass-fiber mat in a

manner similar to the one described above. The impregnated outer wrap

shall then be applied immediately behind the glass fiber reinforcement in a

tight uniform spiral. No wrinkles on the wrapping shall be allowed and

the outer wrap shall be completely bonded to enamel. All inner and outer

wrap shall be moisture free at all times prior to and during application.

8.6 The overlap at the edges of all wrappings shall not be less than 12 mm nor

more than 25 mm. The coating shall be continuous for the full length of

the pipe, except that a length of at least 250 mm but no more than 275 mmon each end of the pipe shall not be coated. The ends of the coating shall

be feathered over length of 25 mm.

8.7 All foreign substances, dirt, shots/sand and other debris shall be removed

from inside of pipe and uncoated length (cut back) on outside of the pipe

before stock piling/shipping. All primer and enamel from inside the pipe

shall be removed with solvents and wiped clean. The coated pipe shall be


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placed in such a manner that the enamel can set, cool and harden without

damage.

8.8 White Washing

The final or finish coat over the outer wrap shall be applied immediately

following final inspection and acceptance of the coating & wrapping.

The white-wash shall not contain any ingredients which may have any

adverse effects on the enamel coat applied (e.g. glue products).

The white-wash shall be reasonably resistant to water. The white-wash

can be applied by brushing, rolling or spraying. White-wash shall be left

off for a distance from the pipe ends on yard-coated pipes sufficient to

allow proper blending between the coating applied to the principal part of

the pipe as per clause 4.7 of this specification.

9.0 INSPECTION

9.1 General

9.1.1 The Companys Representative shall be permitted to test coating, and any

repairs subsequently made to it, in compliance with this specification in

whatever manner and as often as he thinks necessary, and at any time prior

to the coated pipes being transported from yard or prior to concrete weight

coating as the case may be. Such inspection by Company Representative

shall not relieve the Contractor of his responsibility to provide materials

and workmanship as per this specification.

9.1.2 Inspection activities will be coordinated with operations so as to avoid any

unreasonable delay or interference with them. However methods of

operation shall be changed, if necessary, to permit complete inspection

and adequate repair of imperfections and retesting of the latter.

No claims for extra compensation shall be allowed because of time

required for testing and inspection by the Companys Inspector.


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9.2 Holiday detector

9.2.1 All coated and wrapped pipes which have been supported on racks or

skids shall be subjected to a test with an electric holiday detector.

9.2.2 The holiday detector shall be supplied, transported, correctly operated and

always maintained in good working order by the Contractor, who shall

also keep an adequate supply of spare parts. The Company shall not bear

the cost of any delay caused by the incorrect functioning of the holiday

detector.

9.2.3 The holiday detector shall be of a type designed to operate satisfactorily

on coatings or wrappers which may be conductive to dampness or similar

causes.

9.2.4 The holiday detector shall be used to detect all coke particles and other

inclusions such as pinholes, voids, holidays, air bubbles, cracks and other

breaks. Any defective places shall be plainly marked by the Contractor

with chalk immediately after they are detected visually or by the holiday

detector. The holiday detector shall be readjusted as frequently as

necessary to maintain the optimum characteristics as decided by the

Companys Inspector but as a minimum as per AWWA C-203 Section2.14.12.3. At no time shall an employee of the Contractor reset or in any

way alter the holiday detector without the agreement of the Companys

Inspector.

9.2.5 The voltage of the detector shall be regulated to produce an arc which just

bridges an air gap equal to twice the total thickness of the coating,

including wrappers. The detector voltage shall be as per AWWA C-203-

86 Sections 2.14.12.3 and 2.14.12.4.

9.2.6 Movement speed of the holiday detector electrode shall not exceed 20

cm/sec.

9.2.7 Any pipe joint having three (3) or more holidays shall be rejected.

Similarly, any pipe joint having any one holiday bigger than 0.1 square

metre shall be rejected.

9.3 Measuring Coating Thickness

9.3.1 At least 10 (ten) daily checks shall be carried out on finished coating.


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9.3.2 The thickness shall be measured by pushing the point of an approved pit

depth gauge through the coating and wrappers until metal is reached. The

plate of the gauges shall then be lowered until it just touches the outer

surface of the outer wrap, always being placed parallel to the axis of the

pipe and kept normal to the surface. The thickness of any felt shall be

deducted from the figure indicated in order to obtain the thickness of the

enamel. After the checks, the holes made by the gauge shall be closed

again by pressing down the surrounding enamel.

9.3.3 The specified minimum thickness shall be present both at the pipe weld or

any other point.

9.4 Testing the Adhesion of the Coating

9.4.1 At least two tests a day shall be carried out on finished coating at least

after 6 hours from completion of coating. The test shall preferably be not

done at a temperature below 15C.

9.4.2 The adhesion of the coating is determined at three points of the coated

surface, one in the center and two at about 500 mm from the beveled ends.

After the coating has cooled sufficiently, two parallel incisions, at least 25mm apart, are made in the coating right down to the metal and two more

incisions at right angles to and intersecting the first two incisions. An

attempt shall then be made with the aid of a stopping knife or similar tool

to peel the coating off the pipe by applying a uniform force on the coating

directed away from the pipe. The adhesion is unsatisfactory if the layers

of coating part from the primer coat or if the primer coat parts from the

steel.

9.4.3 The areas where the coating has been removed for testing by the inspector

shall be repaired by the Contractor at his own expense.

9.4.4 All areas of coating which do not comply with the requirements of thisspecification and all coating damages and defects shall be repaired or

recoated as directed by the Companys Representative and to his

satisfaction and at no extra cost to the Company.


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10.0 REPAIRS

Repairs to the coating shall be performed by an experienced touch-up

crew.

10.1 All disbonded, delaminated or loose coatings or those in which wrappers

have not been satisfactorily applied shall be removed by scraping. If the

amount of pipe to be recoated is such that, in opinion of the Companys

Representative, it should be done by machine, it shall be done in

accordance with this specification. When the defective area exceeds two

square inches, the surfaces shall be cleaned to the bare metal by scraping

and wire brushing.

10.2 In all cases of repair or touch-up, the felt wrapper including white-wash,

shall be cut away for at least one inch around the area in question.

10.3 The bare metal shall then be reprimed and after the primer has dried

properly, a layer of enamel shall be applied similar to the thickness of the

pipe coating. This shall be followed by a pipe felt wrapper, firmly stuck

in position on the hot enamel.

Repriming of surfaces less than 2 inches square will not be required.

10.4 All areas of coating damaged by inspection shall be repaired by the

Contractor to the satisfaction of the Companys Inspector and at no extra

cost to the Company.

10.5 Any damage to the pipe such as dents, gauges, flattening or any other

damaged caused to the pipe bevels by Contractor shall be repaired or cut

off and rebeveled after obtaining approval from Company Representative.

The cost of such repairs and the cost of pipe lost due to repairs/cut off

shall be to Contractors account.

11.0 MEASUREMENT AND LOGGING

11.1 The Contractor shall prepare a special log book containing all the relevant

data of individual pipe and pipe coating including heat number, diameter,

length, wall thickness, defects, pipe number, batches of materials,

sampling, testing, damages, repairs, rejects and any other information that


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the Company considers to be relevant and required for all incoming bare

pipes and the Company approved outgoing coated pipes as applicable.

The identity of mills pipe number shall be maintained during all phases of

work and finally on the coated pipes.

11.2 The Contractor shall submit this information in the form of a report at

agreed intervals.

12.0 HANDLING AND HAULING OF PIPES

12.1 Contractor shall develop the method of stock piling and loading out bare

and coated pipes and shall receive approval from Companys

Representative prior to handling coated pipes.

12.2 The Contractor shall unload, load, stockpile and transport the bare pipes

using suitable means and in a manner to avoid damages to pipes. Pipe

shall not be allowed to drop or strike objects which will damage the pipe

but shall be lifted or lowered from one level to another by suitable

equipment, preferably by vacuum lifting equipments. Lifting hooks when

used, shall be equipped with a plate curved to fit the curvature of the pipe.

In loading pipe on trucks each length shall be lowered to position withoutdropping and each succeeding length shall rest on special supports on the

truck and shall be separated from the adjacent pipes. After loading,

suitable chains and padding shall be used to tie the load securely to each

bolster. Pipe, when stock piled, shall be placed on suitable skid to keep it

clear of the ground and flood water. Care shall be exercised in handling or

stock-piling pipes in order to avoid distortion, flattening, denting or other

damages. The Contractor shall provide all necessary timber or other

materials required for the stock-piling. While stacking, the number of

allowable layers of bare pipes shall be calculated as per API RP 5L 1 and

shall be agreed with the Company. The stacks must be properly secured

against sliding and shall consist of pipes of the same diameter and wall

thickness. Adjacent stacks of pipes having different dimensionalcharacteristics shall be clearly separated.

12.3 Contractor shall load out the coated pipes onto rail-car or trucks and

barges and shall furnish special loading spacers, bolsters and the like,

approved by the Companys Representative, to protect the pipe during

transport.


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12.4 Coated pipe shall be handled at times with wide non-abrasive or leather

belts or other equipment designed to prevent damage to the coating. All

such equipment shall be kept in proper working order so as to prevent

injury to the coating. The use of tongs, bare pinch bars, chain slings,

protruding rivets, pipe hooks without proper padding, or any other

handling equipment that may be injurious to the coating shall not be

permitted.

12.5 Yard coated pipe shall be raised or lowered to or from stock pile, ground,

barge, rail car or truck by means of brass lined or padded pipe end hooks

engaging the ends of the pipe and carried by wire rope on chain slings

with spreader bars between lifting lines. The bolster of the trailer, or

barge shall have a bearing surface not less than 300 mm wide to give

necessary support to the padding which protects the coating.

Sacks partly filled with sand or saw dust shall be placed on the bolster and

between the outside bottom pipes and bolster stacks. All chains, cables or

other equipment used for fastening shall be padded.

12.6 The maximum stack height for various types of coated pipes shall be

limited to such heights as will not cause damage to the pipe and coating.

The stacking shall conform to the requirements of API RP 5L 1 and APIRP 5L 5. Only coated pipes of same outside diameter and wall thickness

shall be nested together.

12.7 All pipes shall be tightly nested (laid parallel with full length in contact).

Corrosion coated pipes shall not be loaded, piled or nested with the

concrete coated pipes.

12.8 The handling and transportation of pipes shall also meet the minimum

requirements of AWWA C 203-86 Section 4.1.

13.0 DOCUMENTATION

The following documentation shall be submitted to Company for approval

prior to dispatch of coated pipes:

a. Certificates of line pipe received.

b. Test certificates of all raw materials as received from manufacturers

and as tested by Contractor.


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c. All material logging records.

d. Any other document as required by this specification.

All reports shall be marked with Contractors name, work, location,

purchase order no. and items and shall be considered valid only when

signed by Company Representative.

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