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OFFSHORE
DESIGN
MUMBAI
VOL-II REV. 1
SPEC No.
2012
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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VOL-II REV. 1
SPEC No.
2012
SPECIFICATION FOR
COALTAR ENAMEL
COATING OF SUBMARINE
PIPELINE
SHEET NO.
2 OF 21
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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SPECIFICATION FOR
COALTAR ENAMEL
COATING OF SUBMARINE
PIPELINE
SHEET NO.
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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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SPECIFICATION FOR
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COATING OF SUBMARINE
PIPELINE
SHEET NO.
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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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SPECIFICATION FOR
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PIPELINE
SHEET NO.
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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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COATING OF SUBMARINE
PIPELINE
SHEET NO.
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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.