Specification for External Pipeline Coatings

INDEX

1

PURPOSE POSE & SC SCOP OPE E ...................................................................................................................................4

2

INT NTRO RODU DUCT CTIO ION N..........................................................................................................................................4

3

DISTRIB DISTRIBUTIO UTION, N, INTENDE INTENDED D USE USE AND AND REGULATO REGULATORY RY CONSIDER CONSIDERATIO ATIONS NS ..................6

4

DEFI DE FINI NITI TION ONS S...............................................................................................................................................7

5

GENE GENERA RAL L REQU REQUIR IREM EMEN ENTS TS....................................................................................................................9

6.

QUALIF QUALIFICAT ICATION ION OF COATING COATING MATERIAL MATERIALS S ..............................................................................10 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8

7

EQUIREMENTS ..................................................................................................................10 GENERAL R EQUIREMENTS EQUIREMENTS FOR HIGH TEMPERATURE (>80 ADDITIONAL R EQUIREMENTS (>80°C) °C) COATINGS ...................11 CRITICAL P RE-QUALIFICATION T EST FOR PP AND PP HSS HSS ...................................................11 CRITICAL P RE-QUALIFICATION T EST FOR FBE AND LIQUID EPN .........................................11 EPOXY (FBE OR LIQUID EPN) PRIMER .........................................................................................12 PO A DHESIVE M ATERIAL...................................................................................................................13 PO T OPCOAT M ATERIAL ....................................................................................................................13 BATCH CERTIFICATE ...........................................................................................................................14

COATING COATING SYSTEM SYSTEM QUALIFI QUALIFICATI CATION ON (BY APPLICAT APPLICATOR) OR) ....................................................15 7.1 7.2 7.3 7.4

8.

GENERAL ................................................................................................................................................15 APPLICATION P ROCEDURE S PECIFICATION (APS) ....................................................................15 PROCEDURE QUALIFICATION T RIAL (PQT) .................................................................................16 INSPECTION AND T ESTING PLAN .....................................................................................................16

COATIN COATING G SYSTEM SYSTEM APPLI APPLICAT CATION ION ...................................................................................................17 8.1 8.2 8.3

9

SURFACE PREPARATION .....................................................................................................................17 COATING APPLICATION ......................................................................................................................18 CUTBACK ................................................................................................................................................19

QUAL QUALIT ITY Y CONT CONTRO ROL L .................................................................................................................................19 9.1 9.2 9.3.

GENERAL ................................................................................................................................................19 ACCEPTANCE OF F AILED P IPES ........................................................................................................19 TRACEABILITY OF P IPES AND COATING .........................................................................................19

10

COA COATIN TING REPA EPAIR ...............................................................................................................................22

11

MARKING .................................................................................................................................................22

11.1 11.2 12

HANDLI HANDLING NG,, STOR STORAGE AGE & TRA TRANS NSPOR PORT T OF OF BARE BARE & COAT COATED ED PIPE PIPE.............................22

12.1 12.2 12.3 13

GENERAL ................................................................................................................................................22 REQUIRED M ARKINGS ........................................................................................................................22

GENERAL ................................................................................................................................................22 HANDLING OF P IPES ..........................................................................................................................22 STORAGE & STOCKPILING OF P IPES .............................................................................................23 DOCUMENTATION .............................................................................................................................23

DOCUMENT TITLE:

Project No.: MASTER ADCO DOC. NO.ES 30.99.37.0017 REV. 1

EXTERNAL PIPELINE COATINGS

PAGE

DATE : July’14 2 of 37

14

INSP IN SPEC ECTI TION ON AND AND TE TEST ST METH METHOD ODS S ..........................................................................................24

14.1 14.2 14.3 14.4 14.5 14.6 14.7 14.8 14.9 14.10 14.11 14.12 14.13 14.14 14.15

COATING THICKNESS ..........................................................................................................................24 HOLIDAY TEST ......................................................................................................................................25 3LPO PEEL STRENGTH .......................................................................................................................25 IMPACT S TRENGTH ..............................................................................................................................27 INDENTATION .......................................................................................................................................28 THERMAL C RACKING FOR 3LPP .......................................................................................................28 THERMAL AGING TEST ........................................................................................................................29 CATHODIC DISBONDMENT T EST.......................................................................................................30 THERMAL ANALYSIS OF E POXY FILM .............................................................................................30 FLEXIBILITY TEST ..........................................................................................................................31 HOT WATER IMMERSION T EST ...................................................................................................32 LEANLINESS OF B LASTING ABRASIVE M ATERIAL................................................................32 CLEANLINESS MOISTURE C ONTENT OF FB FBE POWDER ....................................................................................33 HOT WATER SOAK .........................................................................................................................33 COATING ADHESION (NCA (NCA) ) TEST ............................................................................................34

15. 15.

FIEL FIELD D JOIN JOINT T COAT COATIN INGS GS .................................................................................................................34

16.

REHABI REHABILI LITAT TATIO ION N COATI COATING NGS S ......................................................................................................34

17.

REF REFEREN ERENCE CES S ..........................................................................................................................................35

18.

APPENDIX A...........................................................................................................................................37

REQUIREMENTS FOR NEW CONSTRUCTION PIPELINE COATINGS ......................................37

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1

PURPOSE & SCOPE

This ADCO Technical Specification (ATS) specifies the minimum requirements for plant and field applied external pipeline coatings of steel pipes, bends and fittings used for the construction of buried or submerged pipelines. It specifies the requirements for coating materials, coating application, inspection and testing, procedures for the qualification of coating materials, and prequalified coating systems. Its scope includes the main pipeline coating, field joint coating and repair/rehabilitation coating. It does not include internal pipeline coating.

2

INTRODUCTION

This ATS has been based on the Shell DEP 31.40.30.31-Gen and ISO 21809-1 for Three Layer Polyolefin (3LPO) external pipeline coatings. In case of any contradiction / conflict or where further details are required, referred shell DEP and ISO 21809 shall be applied with full consultation with the Principal and taking into consideration that the most stringent requirements shall be applied. For FBE coating & Field Joint Coating, related shell DEP and ISO 21809 shall be followed for material qualification, PQT and production testing. The following references shall be part of this Document: -

Shell Dep. 31.40.30.32-Gen “EXTERNAL FUSION-BONDED EPOXY POWDER COATING FOR LINE PIPE” Rev 36. ISO 21809-2 “Fusion-bonded epoxy coatings”2007 - Shell Dep. 31.40.30.37-Gen ““EXTERNAL FIELD JOINT AND REHABILITATION COATING SYSTEMS FOR LINE PIPE” Rev 36. ISO 21809-3 “Field joint coatings”2008 The main amendments to these standards are highlighted as follows; This specification is specially designed for ADCO. ADCO gas pipelines are buried in the sandy soils with high air porosity. Under this type of soil at high temperatures, 3-layer polypropylene (3LPP) and Fusion Bonded Epoxy (FBE)/Epoxy coatings suffer various degrees of thermooxidative degradation damages to reduce their mechanical properties and adhesion to steel substrates. Therefore, the coating systems which are qualified somewhere else in other types of soils may not work properly in Abu Dhabi. This specification includes the generic type of qualified coatings and new coating can be qualified by going through the qualification testing program. A continuously updated list of the qualified coatings with full commercial names will be held at the Technical Centre (Integrity & Operations) & Projects Quality Department in ADCO. However, for the specification, since continuous flow of new coating products and improvements to existing coatings are carried out by the manufacturers, the inclusion of all the latest qualified coatings at all times may not be possible.

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(1) Pre-Qualification Test (Thermo-oxidative Degradation of 3LPO and Epoxy)

In Abu Dhabi sandy soil, the air porosity is high (33 – 48%). Both polypropylene and epoxy suffer severe thermo-oxidative degradation at high temperatures. Commercial polypropylene will embrittle and crack under long term ultra violet (UV) radiation and/or thermo-oxidative aging. FBE and liquid Epoxy Phenol Novolac (EPN) also embrittle and lose adhesion to steel substrates. Therefore, candidate polypropylene, FBE and liquid EPN must go through several critical pre-qualification tests. (2) UV Protection for Topcoat

Epoxy and polypropylene (PP) do not have good UV resistance. Epoxy will chalk and PP will crack under long term UV exposure. UV stabilizers in PP shall not be expected to provide adequate long term UV resistance. For long term storage and/or service under the sun, UV resistant overcoat shall be applied. If PP topcoat has a long term UV exposure in the field, a UV resistant overcoat shall be monitored on a regular basis and be re-applied whenever it is necessary. (3) Strong Coating Inspection Program

There are three requirements for a successful pipeline coating work:  Good specification Good applicator  Strong inspection program  Contractor shall provide a CV for company approval of a highly experienced & certified inspector to conduct the coating inspection job. Inspector shall have a minimum 5 years of experience in pipeline coating and NACE level II certificate or equivalent. Subject to any particular terms and conditions as may be set forth in specific agreements with users, ADCO/ADNOC disclaim any liability of whatsoever nature for any damage (including injury or death) suffered by any company or person whomsoever as a result of or in connection with the use, application or implementation of any ATS, or any part thereof, even if it is wholly or partly caused by negligence on the part of ADCO/ADNOC or other Service Company. The benefit of this disclaimer shall inure in all respects to ADCO/ADNOC. The copyright of ATS vests in ADCO.

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3

DISTRIBUTION, INTENDED CONSIDERATIONS

USE

AND

REGULATORY

Unless otherwise authorised by ADCO/ADNOC, the distribution of this ATS is confined to companies forming part of the Abu Dhabi National Oil Company and to Contractors and Manufacturers/Suppliers nominated by them. This ATS is intended to be used by all involved in the design, procurement, manufacturing, coating and transport of FBE, polyethylene or polypropylene coated line pipe for oil and gas production. If national and/or local regulations exist in which some of the requirements may be more stringent than in this ATS the Contractor shall determine by careful scrutiny which of the requirements are the more stringent and which combination of requirements will be acceptable as regards safety, environmental, economic and legal aspects. In all cases the Contractor shall inform the Principal of any deviations from the requirements of this ATS which are considered to be necessary in order to comply with national and/or local regulations. The Principal may then negotiate with the authorities concerned with the object of obtaining agreement to follow this ATS.

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4

DEFINITIONS 4.1 GENERAL D EFINITIONS

The Contractor is the party that carries out all or part of the design, engineering, procurement, construction, commissioning or management of a project or operation of a facility. The Principal may undertake all or part of the duties of the Contractor. The Manufacturer/Supplier is the party that manufactures or supplies equipment and services to perform the duties specified by the Contractor. The Principal is the party that initiates the project and ultimately pays for its design and construction. The Principal will generally specify the technical requirements. The Principal may also include an agent or consultant authorised to act for, and on behalf of, the Principal. The word “shall” indicates a requirement. The word “should” indicates a recommendation.

4.2 SPECIFIC DEFINITIONS adhesive - an intermediate coating layer to improve adhesion between the primer and the topcoat(three layer system). application procedure specification (APS) – document describing procedures, methods, equipment and tools to be used for coating application applicator - the party that applies the coating to the line pipe in its coating plant. batch – the amount of materials produced within one uninterrupted production run of maximum 8 hours under constant production conditions. chemical pre-treatment - treatment of the blast cleaned pipe surface with a chemical solution before application of the primer to improve adhesion of the primer (Phosphoric acid, Chromate, Silane). cutback – length of pipe left uncoated at each end for joining purposes (e.g. welding). holiday - a defect penetrating through the coating to the steel pipe surface or thin film spots of such dimensions that it is detectable by means of the specified holiday detectors. inspector - the party appointed by the Principal to inspect the Applicator's quality control of coating materials and the coating process. pipeline – those facilities through which fluids are conveyed, including pipe, pig traps, components and appurtenances, up to and including the isolating valves. primer - a coating layer, applied directly onto the blast cleaned and pre-treated steel surface to provide primary corrosion protection. procedure qualification trial (PQT) – application of a coating and subsequent inspection/testing of its properties, to confirm that the application procedure specification (APS) is adequate to produce a coating with the specified properties, carried out prior to the start of production. shift – a set of pipes coated in one production run of which the beginning and end coincide with a change in personnel. In the context of the quality control procedures of this ATS, the maximum duration of a shift is 10 h.

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side extrusion - a coating process whereby hot extruded films of coating materials are wrapped around the pipe in layers. The pipes are moved past the extrusion head in a spiral motion. The extruded coating film is fused together to form a continuous adherent sheath around the pipe (This is the preferred application process to apply polyolefin topcoat in 3LPE/3LPP). three layer system - a pipe coating system consisting of three layers: primer, adhesive and outer topcoat layer. unit of production - unless otherwise specified, a set of pipes coated in one production run on the same coating line, using the same coating technique, having the same nominal diameter and wall thickness and coated with the same coating products. Breaks in production caused by equipment or plant breakdown, factory shutdown or any other interruption exceeding three days shall be the end of a production run. Subsequent start-up constitutes a new unit of production.

4.3

ABBREVIATIONS

APS ARO ATS CD DFT DN DSC EPN FBE FJC HSS PE PO PP PQT Tg UV 3LPO 3LPE 3LPP

Application Procedure Specification Abrasion Resistant Overlay ADCO Technical Specification Cathodic Disbondment Dry Film Thickness Diameter Nominal (mm) Differential Scanning Calorimeter Epoxy Phenol Novolac Fusion Bonded Epoxy Field Joint Coating Heat Shrinkable Sleeve Polyethylene Polyolefin Polypropylene Procedure Qualification Trial Glass Transition Temperature Ultraviolet light Three Layer Polyolefin (including PP and PE) Three Layer Polyethylene Three Layer Polypropylene

4.4 CROSS-R EFERENCES Where cross-references to other parts of this ATS are made, the referenced section number is shown in brackets. Other documents referenced in this ATS are listed in (15).

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4.5

PRE-JOB CONFERENCE AND INSPECTION P ROGRAM

The Principal shall be responsible to organize the pre-job conference to invite at least the following meeting participants: (1)

Contractor,

(2)

Coating Applicator,

(3)

Coating Inspector,

(4)

Coating Manufacturer(s).

5

GENERAL REQUIREMENTS 5.1

GENERAL

A list of coating systems in Appendix A have been developed, from which the Principal should select a coating system for a specific project.

5.2

COATING S YSTEM DESCRIPTION

5.2.1 3LPO Coating System The 3LPO coating system shall consist of three layers: Layer Coating Material Function Main corrosion protection layer with Primer FBE good oxygen barrier and bonding to steel functionalized polyethylene Thin adhesive layer to bond FBE Mid-coat or polypropylene primer and PO topcoat together polyethylene or Improve mechanical damage resistance Top-coat polypropylene and water penetration resistance. DFT of the 3LPO coating system is specified in Table 1 unless otherwise specified by the Principal. The DFT for all coating layers is the same for all pipe diameters. The coating thickness shall be measured in accordance with (14.1).

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TABLE 1

Minimum total coating system thickness polypropylene pipeline coating systems

for

polyethylene

and

Minimum Total Coating Thickness, mm

DN

Polyethylene

Polypropylene

≤ 100

2.5

1.8

> 100 and ≤ 250

2.7

2.0

≥ 250 and < 5000

2.9

2.2

≥ 500 and < 800

3.2

2.5

≥ 800

3.7

2.5

The minimum coating thickness for the FBE primer shall be 300 microns. The minimum coating thickness for the adhesive shall be 200 microns.

5.2.2 FBE Coating System Only 2LFBE shall be used for pipelines with service temperature range above 100 °C to 120 °C. The glass transition temperature (Tg2) of the first layer shall be at least 5 °C above the maximum pipeline design temperature 5.2.3 Liquid Epoxy Phenol Novolac (Phenolic Epoxy or Epoxy Novolac) Coating System Regular liquid epoxy coating has a low Tg with lower immersion service temperature (<65 °C). For higher service temperatures, epoxy phenol novolac coating is normally used. It is more brittle (<1% fracture strain) than FBE and can only be used as either rehabilitation coating to be applied in the field, or a repair coating for FBE.

6. 6.1

QUALIFICATION OF COATING MATERIALS GENERAL R EQUIREMENTS

The coating manufacturer shall carry out and report the coating material qualification for each type of coating materials in compliance with the requirements in this section of this ATS. The test report shall contain test results of the qualification tests in Table 6. The qualification shall be repeated in case of changes in the material composition, changes in the product manufacturing process which influence the material processing behaviour and change in production facility. Where the coating applicator is unable to perform any of the required tests at their facilities, they are required to employ an independent testing lab to perform these tests and notify ADCO to witness the tests if they require.

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6.2

ADDITIONAL R EQUIREMENTS FOR H IGH T EMPERATURE (>80°C) COATINGS

There are two types of new construction coating materials for ADCO external pipeline protection. These coatings can be either 3LPO or FBE. Pipeline coatings in Abu Dhabi sandy soil environment require special attention. The air porosity of the Abu Dhabi sandy soil is high (33 – 48%). Both polyolefin and epoxy resin suffer severe thermo-oxidative degradation at high temperatures. Particularly for polypropylene, the thermo-oxidative degradation is much worse than polyethylene due to its chemical nature. Polypropylene topcoat embrittles and cracks under long term UV radiation and/or thermo-oxidative aging. Normally a few percent of UV/thermal stabilizers are blended in the PP formulation to retard the degradation process. However, the thermal stabilizer package may not retard the degradation at the high temperature effectively. PP also has a high thermal expansion coefficient, which is 10x the one for carbon steel. High residual stresses are developed in PP when the pipeline experiences temperature cycles. PP topcoats crack as a result of the thermo-oxidative degradation and residual stresses when the 3LPP temperature drops. FBE also loses its ductility and adhesion to steel substrates under thermo-oxidation aging. So far, no thermal stabilizers have been developed in the industry to retard the thermo-oxidation of epoxy effectively. FBE’s resistance to thermo-oxidation has to depend on its chemical structure. Polyolefins are not good oxygen barriers and oxygen will permeate through to degrade FBE primer in a 3LPO coating system. Therefore, any candidate coating material, such as polypropylene, FBE and liquid epoxy phenol novolac must go through several critical prequalification tests. These critical pre-qualification tests for high service temperatures (>80°C) are (1) coating material stability, and (2) coating-steel interfacial adhesion durability after a hot air aging and hot water soak. A statement shall be provided by the suppliers of coating materials in compliance with the requirements of (6.3 and 6.4). 6.3

CRITICAL P RE-QUALIFICATION T EST FOR PP AND PP HSS

Since PP cracking under long term thermo-oxidative degradation is a very serious concern, the PP thermal cracking test is the critical pre-qualification test for PP and PP HSS. The PP prequalification test method is summarized in Table 2. A test certificate is the minimum requirement for these tests. Table 2 Thermal Cracking Test for 3LPP and PP HSS Sample Test Sample Size Acceptance Criterion Preparation Method Pipe shape preferred (1) 3LPP No cracking on any of the three pipe samples after aging 6”-12” OD FBE primer / PP as per below temp/time in the hot air oven. ¼-1/2” wall thickness adhesive mid-coat (14.6) Max Service T=100°C if no cracking for 13 wks* 8” in length + / PP topcoat Max Service T=110°C if no cracking for 26 wks* 3 samples minimum (2) HSS Max Service T=120°C if no cracking for 52 wks* *This duration may be reduced by The Principal

6.4 CRITICAL P RE-QUALIFICATION T EST FOR FBE AND LIQUID EPN The serious concern on epoxy is its material stability and loss of interfacial adhesion under high temperature thermo-oxidation aging. The critical pre-qualification tests are summarized in Table 3.

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Table 3 Pre-Qualification Test Protocol for FBE and Liquid EPN Coating Property

Aging Condition

Test Method

Adhesion durability in hot air

DI water immersion for 16 wks minimum* 3%wNaCl, -1.5 vDC, 28 days Hot DI water immersion for 0, 4, 8, 12, 16 wks min, 3 samples minimum for each test time Hot air aging for 0, 4, 8, 12, 16 wks min, 3 samples minimum for each test time

Material stability in hot air Material stability in hot water

Hot air aging for 0, 4, 8,12, 16 wks min, 3 samples minimum for each test time Hot DI water for 0, 4, 8,12, 16 wks min, 3 samples minimum for each test time

Hot water soak Cathodic disbondment Adhesion durability in hot water

(14.14) (14.8) (14.15)

(14.15) (14.10) (14.10)

Acceptance Criterion

No blister, no holidays, zero disbondment <10 mm Pull off test shall be carried out with min. 10 MPa acceptance value. Pull off test shall be carried out with min. 10 MPa acceptance value. “no cracking at 2° of PDL” “no cracking at 2° of PDL”

Note: The test temperature shall be the maximum operating temperature to be qualified.

*This duration may be reduced by The Principal

The coating manufacturer shall carry out and report the material qualification in accordance with the requirements of Table 4-6. The test report shall contain the results of the qualified tests and the test data required in Table 7. 6.5 EPOXY (FBE OR L IQUID EPN) PRIMER

The coating Manufacturer shall conduct the tests in Table 4 using the epoxy coating. The tests in Tables 4-6 are all short term and should be able to be completed in a week. These tests are part of the batch certificates and should come together with the batch of material delivered to the Applicators. Table 4— Requirements for Epoxy Materials Properties

Unit

Test Method

Requirements

Liquid Epoxy (regular) or Epoxy Phenol Novolac (high service temperature)

g/cm3

Density

ISO 2811

manufacturer’s specification  0.05

Solid content of base and curing % volume ISO 3251 agent

manufacturer’s specification

Glass transition temperature (Tg 2)

manufacturer’s specification

°C

(14.9)

FBE

Moisture content

% by mass (14.13)

≤ 0.6

Glass transition temperature (Tg 2)

C

(14.9)

Gel time at 205± 3 °C

seconds

NACE SP0394 or ISO 21809-1 Within 20% of manufacturer’s specification Annex J

Density

g/cm3

ISO 21809-1 Annex N

Manufacturer’s specification

manufacturer’s specification  0.05

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Flexibility test @ 23±2ºC

(14.10)

>2 ˚/PDL (pipe diameter length); No blisters, no holidays

(14.8)

Radial disbondment specification

Cathodic disbondment At 65 C for 24 h, -3.5 vDC (for mm quality control)

per

Manufacturer’s

Note: If a chemical pre-treatment is required for the FBE, it shall be included in the qualification test.

6.6

PO ADHESIVE MATERIAL

The coating Manufacturer shall provide the test data in Table 5 (part of batch certificate) to the Principal. Table 5— Requirements for the PO Adhesive (pellet or powder form) Properties

Unit

Test Method

Requirements

Elongation at break at 23 2C a

%

ISO 527

 400

Tensile yield strength at 23 2Ca

MPa

ISO 527

 12

Vicat softening temperature A/50 (9.8N)

°C

ISO 306

 110

Water content

%

ISO 15512

 0.1

a

2 mm thick compression moulded sheet, test specimen type according to ISO 527-2, strained at 50 mm/min (for PP based adhesives the specimen can be prepared also by injection moulding according to ISO 1873-2)

6.7

PO TOPCOAT MATERIAL

The coating Manufacturer shall provide the test data in Table 6 (part of batch certificate) to the Principal. Table 6— Minimum Requirements for PO Topcoat Properties

Unit

Test Method

Density

g/cm3

ISO 1183 or ASTM D792 Manufacturer specification or ASTM D1505

Elongation at break at 23 2  C a

%

ISO 527

Manufacturer specification

Tensile Yield strength at 23 2  C a

MPa

ISO 527


Drop Weight Impact Strength at 23 2  Cc

J

(14.4)


Vicat softening temperature A/50 (9.8N)

°C

ISO 306

≥110(PE), ≥ 130(PP)

Water content

%

ISO 15512

 0.05

Indentation @23±2ºC @max operating temperature

mm

(11.5)

Oxidation induction time (intercept in the min tangent method)

ISO 11357 D3895

Thermal stability

ISO 21809-1

%

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Requirements

 0.2  0.4

or

ASTM

 30

at 220 C

MFR  35



PAGE


a:Preparation of the test specimen according to ISO 1872-2 for PE and ISO 1873-2 for PP (2mm thickness), at 50mm/min crosshead speed.

6.8

BATCH C ERTIFICATE

Batch certificates shall be supplied by the coating Manufacturer of each layer material and shall contain the information given in Table 7. The batch certificate shall state test methods and acceptance criteria. Table 7— Batch certificate Coating Material Content

Liquid Epoxy

FBE

PO Adhesive

PO Topcoat

Identification of the manufacturer

x

x

x

x

Product name & material type

x

x

x

x

Batch identification

x

x

x

x

Date and place of manufacturing

x

x

x

x

Shelf life at storage temperature in months

x

x

x

x

Density

x

x

x

x

Viscosity of base and curing agent

x

Solid content (%v) & thinner product and max amount

x

Pot life

x

Melt flow rate

x

x

Application method (extrusion or powder)

x

Chemical pre-treatment (generic name and application procedure)

x

Gel time

x

Particle size

x

Moisture / water content

x

x

x

x

x

x

x

x

x

x

IR scan

x

Surface preheating temperature

x

Glass transition temperature, Tg

x

x

Melting point, T m Colour

x

Technical properties

Table 4

DOCUMENT TITLE:

x Table 4

Table 5



Table 6

PAGE


7 7.1

COATING SYSTEM QUALIFICATION (BY APPLICATOR) GENERAL

Each coating system shall be qualified by the Applicator. Qualification shall be carried out separately for each coating line. The Applicator shall carry out and report the coating qualification in accordance with the requirements of this ATS. The test report shall contain the test results of the qualification tests and data required in Table 9 and 10. The Applicator shall apply coating materials qualified in accordance with the requirements of (6). Qualification shall be repeated in case of modification to the coating line, coating materials or application procedures. Coating System Prequalification testing and inspection requirements for External Pipeline Coatings shall be held under the responsibility of TC (I&O) and Projects Quality Department to ensure that the 2-layer FBE coating shall be fit for the intended high temperature service. 7.2

APPLICATION P ROCEDURE SPECIFICATION (APS)

Prior to the start of coating production and any specified PQT (Procedure Qualification Trial), the Applicator shall prepare an APS, including: incoming inspection of pipes and pipe tracking; (1)

(2)

product data sheets for coating materials, including any materials to be used for coating repairs;

(3) (4)

product data sheets for abrasive blasting materials; certification, receipt, handling and storage of materials for coating and abrasive blasting;

(5)

procedure for cleaning of all application equipment;

(6)

preparation of the steel surface including control of environmental parameters, methods and tools for inspection, grinding of pipe surface defects and testing of surface preparation; coating application, including tools/equipment for control of process parameters essential for the quality of the coating;

(7) (8)

lay-out sketch or flow diagram for the coating plant;

(9)

methods and tools/equipment for inspection and testing of the applied coating;

(10)

repairs of coating defects and any associated inspection and testing;

(11)

stripping of defective coating;

(12)

preparation of coating cutback areas;

(13)

marking and traceability;

(14)

handling and storage of pipes;

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(15)

any special conditions for dispatch of coated pipes, including protection of pipe ends;

(16)

documentation on coating quality control inspection and testing.

The APS shall cover all items associated with quality control as defined in this ATS. It shall be available to the Principal on request at any time during production. The APS including any revisions shall be approved by the Principal prior to the start of production and any specified PQT. 7.3

PROCEDURE QUALIFICATION T RIAL (PQT)

The APS shall be verified by a PQT (1) All items shall be performed on the processes and inspection/tests in the APS from surface preparation to preparation of pipe ends. (2) The specific process parameters shall be selected to be used during the PQT so that the suitability of the ranges and combinations specified in the APS can be verified (e.g. a maximum value for one parameter may be applied in combination with a minimum value for another, if deemed critical). (3) Requirements for the frequency of testing and inspection, methods and acceptance criteria are contained in Table 9 and Table 10. (4) The results from the PQT shall be documented in a report, including the process parameters used, the APS and the coating material certificates. Any recommendations for revision of the APS that are to be applied for production shall be highlighted in the report. (5) PQT shall be carried out for shop coating, field joint coating and repair material of both shop & field.

7.4

INSPECTION AND TESTING P LAN

The Applicator shall prepare an inspection and test plan and a daily log to record all inspection and quality control data. Properties of the applied coating are listed in Table 8. Table 8 - Properties of the Applied Coating Properties

Test Method

Acceptance Criteria

Visual & free of defects and discontinuities, (14.2) delaminations, separations and holidays.

Appearance & holiday Drop weight Impact strength at 23± 3  C

(14.4)

>7J/mm (3LPE),

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 10J/mm

(3LPP)



PAGE


Indentation at 23± 3  C

(14.5)

at Max service temperature

≤ 0.2mm (PE), ≤0.1mm (PP), No test for Epoxy ≤ 0.4 mm for PE & PP, ≤10% DFTfor Epoxy

PO Elongation at break at 23  3  Ca

ISO 527≥ 400% 3

Peel strength b

(14.3)

Degree of cure of FBE

(14.9)

PO material stability during application of ISO topcoat process 1133 Average radius of cathodic disbondment at:23 3  C, -1.5 v, 28 days 65 °C/24h/-3.5v (QC test in production)



≥ 15 (PE), 25 (PP) N/mm at 23± 3 °C ≥ 3(PE), 4(PP) N/mm at max service temp  Tg

= -2C to + 3 C

≤ 20 ΔMFR for PE, ≤35 ΔMFR for PP ≤ 7 mm

(14.8)

≤ 7 mm ≤ 15 mm

Max service temp, -1.5 v, 28 days Flexibility of FBE at 23  3  C

(14.10)

> 2% pipe diameter length

3LPO delamination resistance test

(14.11)

Average ≤2mm and maximum ≤3mm

a

No single recorded value shall be lower than 30% of the requirements.

b

No interfacial adhesive failure between steel and FBE.

8 8.1

COATING SYSTEM APPLICATION SURFACE PREPARATION

8.1.1 Initial Preparation All dirt and contaminations, such as oil and grease shall be removed, by a suitable solvent or biodegradable detergent, prior to abrasive blasting in accordance with the requirements of SSPCSP1. All pipes shall be dry prior to entering the abrasive blast cleaning cabinet. Pipe surface temperature shall be at least 3C above the dew point prior to abrasive blast cleaning. 8.1.2 Abrasive Blast Cleaning The abrasives shall meet the requirements of ISO 11124. The abrasives shall be clean, dry and free from contaminates in accordance to SSPC-AB1, AB2 and AB3 or ASTM D4940. The pipe surface shall be cleaned of mill scale, rust and other foreign matter by an abrasive blast cleaning method to achieve a minimum surface cleanliness of Sa 2½. For stainless steel pipes, non-ferrous abrasives shall be used for blast cleaning. The surface profile shall be as specified by the epoxy coating Manufacturer. If not specified, the surface profile shall be 2-4 mil (50-100 μm) to be measured in accordance with the requirements of ISO 8503-4 (digital stylus profilomer, Rz, with a cut off length of 2.5 mm) in the coating plant and with ISO 8503-5 (Replica Tape) in the field. During blast cleaning the pipe surface temperature shall be simultaneously higher than 5 °C and more than 3 °C above the dew point. In the field operation, the relative humidity shall also be less than 85%.

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Immediately after blast cleaning, all remaining weld splatter, lamination and irregularities shall be removed from the pipe surface by grinding. The maximum allowable area of grinding shall be 10 cm2 per meter of pipe length or 0.5% of pipe surface area, whichever is lower. Any treated surface with an area larger than these limits shall be re-blasted to the cleanliness and roughness as specified above. 8.1.3 Surface Dust Contamination The dust level on the blast-cleaned surface shall be of Class 1 for both size and quantity in accordance with ISO 8502-3. 8.1.4 Surface Cleanliness and Pre-treatment The blast cleaned pipe surfaces shall be pre-treated with phosphoric acid in accordance with the specification of the manufacturer. Additional chemical treatment by chromate shall be optional taking into consideration local and international HSE regulations. The maximum residual chloride level on the blast-cleaned surface shall be 20 mg/m2, in accordance with ISO 8502-2, ISO 8502-9 or any other method approved by the Principal. 8.2

COATING A PPLICATION

8.2.1 General Before coating, the pipe surface shall be cleaned from all dust and foreign matter using clean dry compressed air or vacuum cleaning. Cleanliness of the compressed air shall be tested with a blotter test and shall be free of any trace of oil. Blast cleaned pipes shall be coated within 4 h and the surface cleanliness shall remain to be Sa 2½. Pipes whose coating is delayed beyond this period, or pipes showing any visible rust stains, shall be blast cleaned again. During coating, the beveled ends of the pipes and the pipe bore shall be protected against mechanical damage and against contamination with coating material. Uncoated pipe ends shall receive a temporary protective coating for transit. 8.2.2 FBE Application The application of the coating shall be strictly in accordance with the coating Manufacturer's application procedures. During the application of the coating system, the pipe preheating temperature shall be monitored and recorded using contact pyrometers. Temperature measuring Tempsticks may be used to measure temperature only if agreed upon by the Principal prior to coating, and shall be validated for temperature control during qualification and production of the coating system. The FBE DFT shall be in accordance with Appendix A. The FBE primer shall be cured and the degree of cure shall be in accordance with Table 8. 8.2.3 PO Adhesive Mid-coat Application For multi-layer systems, the temperature and time between subsequent layers shall be controlled to obtain sufficient interlayer adhesion. The mid-coat DFT shall be in accordance with Table 1. 8.2.4 PO Topcoat Application The applied PO topcoat shall be cooled to a temperature which prevents handling damage during finishing and final inspection. Batches of polymer shall be used in the same sequential order in which they were manufactured. The coating DFT shall be in accordance with Table 1.

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8.3

CUTBACK

At the pipe ends, the coating shall be cut back over a length of 150 ± 20 mm unless otherwise specified by the Principal. At the cutback, the coating edge shall be shaped to form a bevel angle of 30°or less. The FBE primer shall leave 2-5 mm long toe (extension). For stainless steel pipes, non-ferrous or stainless steel tools shall be used

9 9.1

QUALITY CONTROL GENERAL

During production application of the coating, the Applicator shall carry out all quality control activities needed to ensure that the coating is being applied in accordance with the approved coating application procedures and that the final product complies with the requirements of this ATS. The minimum quality control tests to be performed shall be as indicated in Table 9 & 10. 9.2

ACCEPTANCE OF F AILED PIPES

Pipes which fail to meet the requirements of Table 9 shall not be coated until the cause has been identified and corrected. Pipes which fail to meet the requirements of Table 10 shall be retested for the parameters found to be out of specification. If the retest also fails to meet the requirements in Table 10, two pipes in the coating sequence prior to the pipe which failed and two pipes in the sequence after that pipe shall be retested. If the results of all retested pipes are satisfactory, the coating shall be considered acceptable excluding the pipe that failed. If the test fails, the total production back to the last passed test shall be blocked and further testing shall be initiated by the Applicator and agreed with the Principal. In case of a confirmed failure, the coating shall be rejected. No pipes shall be dispatched from the coating yard before the Principal has approved the quality control results. The Principal retains the right to reject any shift's or day's production if the reject rate of that production is more than 10 % and/or if sample tests are found to be outside the specification in this ATS. In addition, the Applicator may be required to stop production and carry out a full investigation into the source of the problem; the Applicator shall submit the results to the Principal before receiving permission from the Principal to recommence production. 9.3.

TRACEABILITY OF P IPES AND COATING

The Applicator shall ensure that individual pipes are fully traceable during and after the coating process. If the serial number of the pipe as given in the pipe mill is removed or obliterated, it shall be reapplied. The Applicator's own serial number shall be indicated on the pipe and records shall be kept to identify the sequence and time of coating and the batch of materials used for each pipe.

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Table 9 Quality Control Requirements for Surface Preparation Properties

Test Method

Requirements

Frequency

Frequency

(Qualification)

(Production)

each pipe

each pipe

once

every 4 h

once

every 4 h

Surface condition before blasting

Visual inspection

Environmental conditions

Calculation

Pipe temperature before blasting

Contact Pyrometer

Size, shape and properties of abrasive

Visual + certification ISO 11124 (metallic) ISO 11126 (nonmetallic)

conformity to certificate, compliance to manufacturing/ working procedures

once

every day

Water soluble contamination of abrasives

Clause 14:12

Conductivity max. 50 µS/cm

once

every shift

Soluble salt after blasting,

Potassium ferricyanide and following conductive measurement, ISO 8502-9 and ISO 11127-6

salt content (as NaCl) 2 max. 20 mg/m

each pipe

every 4 h every 4 h if salt presence is indicated

Surface profile (Rz)

ISO 8503-4 or ISO 8503-5

50 to 100 μm

5 pipes

every 1 h

Cleanliness of blast cleaned surface

ISO 8501-1

Sa 2½

each pipe

each pipe

Presence of dust after dust removal

ISO 8502-3

Max. Level 1

5 pipe

every 1 h

Visual Inspection of pipe prior to introduction to coating line

visual

no rust

each pipe

each pipe

Temperature of extruded adhesive and polyolefin, °C

Non-contact Thermometer

compliance to APS

once

every 1 h

Preheating temperature before coating

Contact Pyrometer

compliance to APS

each pipe

every 0.5 h

free of contaminations as determined at time of measurement Minimum 3°C above the dew point

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Table 10

Quality Control Requirements for Applied Coatings

Properties

Unit

FBE DFT

μm

PO adhesive thickness

μm

Degree of cure

°C

Appearance & Holiday Total thickness of coating Impact resistance

Test Method ISO 2808 or ASTM D4138 ISO 2808 or ASTM D4138

mm

Frequency Qualificati on

Requirements

300-400

1st pipe

1/shift

150-250 (powder) 200-300 (extrusion)

1st pipe

1/shift

(14.9)

∆ Tg = -2C to + 3C

1st pipe

1st pipe and 1/shift

(14.2)

Table 8

each pipe

each pipe

(14.1)

Table 1

5 pipes

every 10 pipe

J/mm

(14.4)

Table 8

3 pipes

Peel strength

N/mm

(14.3)

Table 8

5 pipes

Indentation

mm

(14.5)

Table 8

once

Elongation at break

%

ISO 527-2 or 3

Table 8

once

Cathodic disbondment

mm

(14.8)

65C / 24h / -3.5V

3LPO delamination resistance test

mm

(14.11)

Flexibility

°/PDL

Frequency Production

one of 100 pipes (min. one pipe per shift) every 4 h one of 100 pipes (min. one pipe per shift) one of 100 pipes (min. one pipe per shift)

once

1/day

Table 8

once

1/day

(14.10)

Table 8

once

No test

Once

1st pipe per shift

In process degradation of PO

%

ISO 1133

ΔMFR: max. 35 for PP; max. 20 for PE between raw & applied material

Cutback

mm & degree

Measuri ng

8.3

each pipe

recorded 1/h

FBE toe @ cutback

mm

Measuri ng

2 – 5 mm

each pipe

each pipe

Visual (14.2)

No holidays

Once for validation

Each defect

Coating repairs

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10

COATING REPAIR

Defects in the finished coating caused by the application process, transportation, handling and storage in the coating plant or in the storage area as well as those which have been subjected to destructive testing shall be repaired. The defect area shall not exceed 10 cm 2 and the total number of defects being repaired shall not exceed one defect per meter length of pipe unless otherwise specified. If the size or number of defects exceeds these limits the affected pipe shall be stripped and recoated. The Applicator and/or Contractor shall submit detailed procedures for coating repairs for approval by the Principal. All pipes that have been repaired shall be fully re-examined in accordance with the quality control procedures (9). Records shall be kept of all repaired pipes and shall include the repair and re-test details.

11

MARKING

11.1 GENERAL

Coated pipe shall be marked in accordance with the requirements of 11.2 and with any additional markings specified in the purchase order. Additional markings as desired by the Applicator shall be by agreement. 11.2 R EQUIRED MARKINGS

The following markings shall be placed on the coating: 1) Mill Pipe No.; 2) Heat No.; 3) Length. Marking shall be carried out using a method such as stencil painting or printing, to ensure legible and indelible.

12

HANDLING, STORAGE & TRANSPORT OF BARE & COATED PIPE

12.1 GENERAL

The Contractor shall take receipt of the pipes delivered by the pipe Manufacturer/Supplier, and shall keep a record of the serial numbers of the delivered pipes. Upon receipt, the pipes shall be inspected for transport damage or other defects. Damaged pipes shall be separately stored and reported to the Principal. Repairs shall only be carried out after approval by the Principal. During the various stages of the complete coating process, the Contractor shall ensure that all pipes shall be handled, stored and transported in such a manner that no damage is caused to the pipes and the applied coating. Instructions by the pipe Manufacturer and/or coating Manufacturer shall be strictly followed. The following instructions shall also apply. 12.2 HANDLING OF P IPES

Bevel protectors and/or end caps as installed by the pipe Manufacturer shall always be reinstalled after coating and before handling of the pipes.

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Pipes shall only be lifted by means of slings, lifting hooks or vacuum lifters, fitted with suitable spreader bars. Hooks shall be padded with soft material to prevent damage to the bevelled ends. Wire ropes shall not be used to lift coated pipes; chains shall never be used to lift the pipes. Lifting trucks or front-end loaders shall have soft padded forks or grips to prevent damage to pipes or pipe coating. Coated pipes shall not be rolled or dragged over the ground. Pipes shall not be lifted in bundles without prior approval by the Principal. When more than one pipe is lifted, separate slings or hooks shall be used for each pipe and coated pipes shall be provided with soft padding between the pipes. For handling of stainless steel pipes, transport equipment and conveyor shall be padded to prevent contact with carbon steel. Pipes that are damaged during processing shall be repaired in accordance with the requirements of the applicable pipe specification or standard. Coating that is damaged after the holiday inspection shall be repaired in accordance with the requirements of (10) 12.3 STORAGE & STOCKPILING OF P IPES

Pipes shall be stored in designated areas. Pipes shall not be stored with other consignments or pipes for other contracts. Pipes shall be stacked only to such a height that no damage is caused to the pipes or their coating due to the weight of other pipes. Pipe supports shall be spaced such that no bending of pipes occurs. Pipe supports shall be made of soft padded wooden bolsters or sand rows, free of stones, covered with plastic sheets. The pipe surface shall not be in contact with the soil. Piles of pipe shall be secured by wooden wedges or ground pins, provided with adequate padding to prevent coating damage, and of sufficient size to prevent collapse of the piles. Coated pipes shall be stacked using soft separators such as rubber pads or tyre tread. When stored outdoors, pipes shall be placed at a small angle to allow drainage of any rainwater from the inside of the pipes.

13

DOCUMENTATION

The Contractor shall keep accurate records of all relevant data of the coating process. This documentation shall, as a minimum, consist of: copies of the coating system information as specified in (5); -

copies of qualification information as requested in (6);

-

copies of, or reference to, all procedures for coating of the pipes;

-

serial numbers of all pipes as given by the pipe Manufacturer (e.g. by copies of the pipe mill data sheets);

-

serial numbers as given by the coating Applicator (if applicable) correlated with the Manufacturer's serial numbers;

-

the order of coating, the day and shift of coating of each pipe;

-

the batch numbers of the coating materials, the day and time of loading of each batch;

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-

serial numbers of rejected pipes and the reason for rejection;

-

records of any repairs;

-

the results of all quality control testing (9);

-

records of temperatures during the coating process for each pipe, with the processing time of every tenth pipe marked on the temperature chart with the pipe number;

-

names and signatures of the responsible persons for the coating process and quality control.

This documentation shall be submitted to the Principal after completion of the coating work, together with the testing and inspection instruments’ calibration certificates.

14

INSPECTION AND TEST METHODS

14.1 COATING T HICKNESS

14.1.1 Equipment The coating thickness shall be measured by an electromagnetic thickness gauge, in accordance with ISO 2808, method 6A (magnetic induction principle) or 6B (permanent magnet pull-off principle). 14.1.2 Procedure The thickness gauge shall be calibrated at least once per shift in accordance with the instruction specified by the DFT gage manufacturer. The coating DFT shall be measured at three locations per pipe, equally spaced along the length of the pipe. At each location, the thickness shall be measured at four positions, equally spaced around the circumference of the pipe. At least 12 single readings in accordance with ISO 2808. The average of the 12 readings shall be within the specified DFT range (Appendix Table A1 and A2). The minimum reading shall be no less than the 80% of the lower DFT limit in Table A1 and A2. If the DFT reading is out of the specified range, the Applicator shall report to the Principal for resolution. The DFT reading at the weld crown may allow 10% lower than the one in smooth region. 14.1.3 Test Results and Reports The results shall consist of the calculated arithmetic mean of the all measurements. The test report shall at least include: (1) specimen identification, (2)

instrument used.

(3)

test method

(4)

test results

(5)

Specified DFT range in Appendix A.

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14.2 HOLIDAY TEST

14.2.1 Equipment A holiday test shall be carried out by means of an adjustable high voltage holiday tester having an audible and visual alarm. The scanning electrode shall consist of a metal brush or coil spring, fitting the diameter of the coated pipe. 14.2.2 Procedure The earth connection shall be made directly on the pipe. The test voltage for 3LPP/3LPE shall be 10 kV for each 1 mm of coating thickness with a maximum of 25 kV. The test voltage shall be checked at least once per shift by means of a certified voltmeter. In case of dual layer FBE the NACE 0490 formula shall be followed. When the holiday test is carried out the external pipe surface shall be free of water. The electrode shall be moved over the pipe surface at a speed of not more than 0.3 m/s. The entire pipe surface shall be covered by the test. When used in conjunction with the impact resistance test, a suitable metal brush shall be used to inspect the impacted surface. 14.2.3 Test Results and Reports The results shall consist of the number of holidays detected. Each holiday shall be marked for repair. The test report shall at least include: (1) identification of test specimens; (2)

voltage used

(3)

instrument used

(4)

number of holidays

14.3 3LPO PEEL S TRENGTH

14.3.1 General The 3LPO peel strength shall be determined by measuring the force required to peel a strip of coating from the pipe surface at a constant rate. Any method using a force gauge of spring balance type shall not be allowed. For testing at elevated temperatures, a sample of pipe shall be conditioned for at least one hour at the test temperature. The test shall be carried out under conditions that ensure that the temperature of the outer steel surface is maintained at the required test temperature. The surface temperature shall be monitored during the test and the results reported.

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14.3.2 Equipment The peel test equipment shall consist of (1) Cutting knife (2)

Tensile test machine with a load cell of capable of recording the peel force continuously at a pull rate of 10 mm/min, as in Figure 1 for small diameters or in Figure 2 for large diameters.

Figure1 Peel Strength Test Equipment for a Small Diameter Pipe

Figure 2 peel Strength Equipment for a Large Diameter Pipe 1-coated pipe, 2-coating -

14.3.3 Test Procedure A pipe ring of appropriate length shall be cut from the pipe. A strip of coating with a width between 20 mm and 50 mm shall be peeled off the pipe surface in the circumferential direction over the full pipe circumference or at least 160 mm length, by means of a tensile machine and the stripping arrangement shown in Figure 1 or 2. For small diameter pipes, the pipe ring shall be free to rotate about its axis, as shown in Figure 1. For large diameter pipes, the pipe shall be supported during the test to prevent movement. The cut end of the coating strip shall be secured to one of the gripping jaws of the test machine and peel perpendicular to the pipe axis. The coating shall be peeled at an angle of 90° to the pipe surface with a pulling rate of 10 mm/min. The force required for the peeling shall be continuously recorded. The peeling force shall be the mean value of this recording, disregarding the first and last 20 mm. The recording

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shall not show any section of more than 20 mm length having a peeling force less than 75 % of the mean value. The peel strength is calculated as: Error! Objects cannot be created from editing field codes. (N/mm) where:

Fm is the mean pulling force in N

W is the width of the strip in mm. The peel tests shall not be carried out on coating over welds, coating overlaps or within 1.5  DN or 300 mm, whichever is smaller, from the edge of the coating. The test strips shall be at least 50 mm apart.

14.3.4 Test Result and Report The test result shall be calculated by dividing the peel force data for 140 mm of peeling into seven intervals of 20 mm and the first and last intervals discarded. The peel strength shell be calculated from the remaining data. The average peel strength shall be the arithmetic mean over the 100 mm length. The average peel strength shall meet the requirements of Table 8 and no single recorded peeling value shall be more than 30% below the specified value. The test report shall at least include: (1) Identification of test specimens; (2)

Procedure used’

(3)

Test instruments used;

(4)

Test results.

14.4 IMPACT STRENGTH

14.4.1 Equipment The impact test shall be performed by means of a commercial falling weight impact testing machine as described in ASTM G14. The falling weight shall have a smooth hemispherical head with a diameter of 25 mm. 14.4.2 Procedure The Impact Test shall be carried out at a temperature of 23  3C Before the test, a holiday detection test shall be conducted to identify the defective points and to avoid making impact at these locations. The pipe sample shall be placed horizontally on a rigid and stable support to reduce its elastic response. Each test shall comprise a series of ten impacts, using a combination of weight and height corresponding to the predetermined impact energy. The impacts shall not be on pipe welds, coating overlaps or within 1.5  DN from the edge of the coating. The impacts shall be at least 50 mm apart. After the impacts have been made, each point of impact shall be tested for the presence of a holiday in accordance with (14.2). The number of holidays shall be noted.

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14.4.3 Test Result and Report (1) identification of test specimens; (2) instrument used; (3) procedure used; (4) test result. 14.5 INDENTATION

14.5.1 Equipment (1) Penetrometer comprised of (a) cylindrical indenter with a diameter of 1.8 mm (cross section area 2.5 mm2) on the top of which is mounted with a weight. The total weight (indenter plus weight) shall be 25 ± 0.5 N. (b) A dial gauge of appropriate scale; (2) A circulated oven or a hot plate, thermostatically controlled to ± 2 C to heat the test sample to the designated temperature. 14.5.2 Procedure The test shall be performed on a coupon cut from the pipe or on strips of polyolefin removed from the pipe surface. The test sample shall reach the test temperature before testing. A total weight of 25 N shall be loaded on the sample. The test will last until the displacement reading stabilized without change. It may take 1-2 days to reach the steady state. 14.5.3 Test Results and Report The test report shall at least include: (1) identification of test specimens; (2)

instruments uses;

(3)

procedure used;

(4)

test results.

Test Temperature shall be as per table 7d of shell DEP 31.40.30.31-Gen. Test shall be carried out at (23 +/- 2) °C and maximum operating temperature 14.6 THERMAL C RACKING FOR 3LPP

14.6.1 Equipment An air circulated oven with a temperature range to 200 C should be sufficient.

14.6.2 Procedure (1) Test Samples – Only 3LPP pipe and PP heat shrinkable sleeve samples shall be used. Three pieces of pipe samples of less than 300 mm diameter and 200 mm length are preferred. If only bigger pipe size is available, the large size pipe can be cut into the three samples of 300mm x 200mm.

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(2) Oven aging - Maintain the air oven at 150 ± 2 ˚C and leave three PP samples in the oven for 8 weeks continuously. After 8 weeks, take samples out of the oven to cool to room temperature for 2-4 hours. Examine the samples for cracking. If any of the three samples shows a visible crack. Stop the test and record the oven aging time. If no cracking, put the samples back to oven. Take the samples out once a week to room temperature to check for cracking. The test repeats until any sample cracks. (3) PP Cracking Estimation If none of the three pipe coating specimens cracks over 13 weeks test period, the 3LPP is qualified for 100 C service temperature. If no cracking for over 26 weeks, the 3LPP is qualified for 110C. If no cracking for over 52 weeks, the 3LPP is qualified for 120 C.

14.6.3 Test Results and Report (1) identification of test samples; (2) type of air oven used; (3) aging time to crack; 14.7 THERMAL A GING T EST

14.7.1 Equipment (1) Air circulation oven, temperature controlled at a test temperature within ±3°C. (2) Melt flow tester 14.7.2 Procedure (1) Test temperature and duration – Test Material Test Duration, hour Test Temperature, °C PE 4800 100 ±3°C 240 150 ±3 °C PP, service temperature ≤80°C PP, service temperature (T) (T-70) x 24 150±3 °C >80°C (2)Three melt flow rate measurements shall be undertaken on the test sample in accordance with ISO 1133. (3) The MFR shall be calculated as the arithmetic mean of the three measurements. (4)

The melt flow rate MFR 0 shall be calculated in accordance with ISO 1133 on a test sample of identical shape which has not been placed in the oven aging.

14.7.3 Test Results and Report The result shall be expressed as the percentage variation of the melt flow rate (ΔMFR) after exposure using the following equation: Error! Objects cannot be created from editing field codes.Error! Objects cannot be created from editing field codes. Where MFR 0 = the melt flow rate measured before exposure MFR 1= the melt flow rate measured after exposure

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The test report shall at least include: (1) Identification of test samples; (2) Instrument uses; (3) Test results. 14.8

CATHODIC DISBONDMENT TEST

(1)

14.9

CD Test shall be carried out in accordance with ISO 21809-1:2011 and 21809-2: 2011. THERMAL A NALYSIS OF E POXY FILM

Testing of production coating shall also require the pipe number or identification.

14.9.1 Equipment (1) Differential scanning calorimeter with cooling accessory; (2) Balance, accurate to 0.1 mg; (3) Aluminum pans; (4) Nitrogen gas, dry analytical grade. 14.9.2 Procedure (1) The degree of cure of the FBE shall be measured by means of differential scanning calorimetry in accordance with ASTM D 3418, to determine the glass transition temperature (Tg) of the FBE. (2) For qualification test of FBE powders, run the following heating cycles, starting with run (a) as the conditioning run for FBE powder only. Run (a) – Heat the sample from 25°C ± 5°C to 70°C ± 5°C at a rate of 20°C/min, then immediately cool the sample to 25°C ± 5°C Run (b) – Heat the sample from 25°C ± 5°C to 275°C ± 5°C at a rate of 20°C/min, then immediately cool the sample to 25°C ± 5°C, Keep for 3 minutes at 25°C ± 5°C Run (c) – Heat the sample from 25°C ± 5°C to Tg + 40°C at a rate of 20°C/min, then immediately cool the sample to 25°C ± 5 °C (3) For 3LPO coating system qualification, run the following heating cycles, starting with run (a) as the conditioning run for the FBE samples removed from the 3LPO coating system,. Run (a) – Heat the sample from 25°C ± 5°C to 110°C ± 5°C at a rate of 20°C/min and hold for 1,5 min, then cool the sample to 25 °C ± 5°C. Run (b) – Heat the sample from 25°C ± 5°C to 275 °C ± 5°C at a rate of 20°C/min, then cool the sample to 25°C ± 5 °C. Wait 3 min at 25 °C ± 5°C. Run (c) – Heat the sample from 25°C ± 5°C to Tg + 40°C at a rate of 20°C/min, then cool the sample to 25°C ± 5°C. The glass transition temperature is Tg1 for the run (b) and Tg 2 for run (c). The degree of cure is related to the difference between Tg1 and Tg 2, which shall be determined as: ΔTg = Tg2- Tg1 The required cure characteristics are: Tg = -2 C to + 3 C

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When the FBE film samples are taken from the 3LPO coating system, care should be taken to remove samples to avoid the inclusion of steel debris, adhesive, or PP. For certain epoxy powders a different heating cycle may be necessary in accordance with the epoxy manufacturer technical data.

14.9.3. Test results and report Record the following information on uncured and cured material: ⎯ Type of material and batch number; ⎯ Date of test; ⎯ Type of DSC equipment; ⎯ For the epoxy powder: T g1, T g2, Δ H ; ⎯ For the epoxy liquids: T g2, Δ H ; ⎯ For the cured coating film: T g3, T g4, ΔT g, Δ H 1 and C . 14.10

FLEXIBILITY TEST

14.10.1 Equipment (1) Fixed radii mandrel bending machine; (2) Stereo microscope; (3) Wet sponge holiday detector. 14.10.2 Procedure (1) It is applicable to both FBE qualification and 3LPO coating system qualification. For the latter, only the FBE primer of the 3LPP coating system shall be tested. (2) Coated samples (200 mm x 25 mm x thickness of pipe wall) taken from a FBE coated pipe joint. (3) The bare face of the test specimen shall be bent over the fixed-radius steel mandrel. The deformed coating surface shall be examined for signs of cracking using a stereo microscope and a low-voltage holiday detector. If no cracking is detected, the test specimen shall be bent over a mandrel with a smaller radius. The process shall be repeated until cracking is detected. The flexure strain of the coating material shall be calculated using the following equation. Error! Objects cannot be created from editing field codes. Where

t = steel panel thickness (mm or in.) c = coating system thickness (mm or in.) R = mandrel radius (mm or in.) Because discrete bending radii are used, the true flexure strain is actually somewhere between two consecutive mandrel radii. For practical purposes, the flexure strain of the coating system shall be reported as the average of these two values.

14.10.3 Test Results and Report The test report shall at least include: (1) identification of test samples; (2) instruments used; (3) procedure used; (4) sample DFT and steel thickness (5) test results for FBE or epoxy flexural stain in % and °/PDL. DOCUMENT TITLE:



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14.11

HOT WATER I MMERSION T EST

High residual stresses in 3LPO may cause FBE-Steel interfacial delamination. delamination resistance test is to evaluate the resistance to delamination.

The

14.11.1 Equipment (1) Hot water bath (2) Pocket or utility knife 14.11.2 Procedure (1) For small diameter 3LPO pipes (<75 mm), the plant applied test pipe samples should be cut into 150 mm pipe rings. For larger pipes, test samples should be cut into 150 mm x 100 mm segments. The cut surfaces shall be wet grinding with 120 grit abrasive paper. Three samples shall be prepared for each test. (2) The specimens shall be immersed in the hot water bath. The water temperature shall be 80 °C for 3LPE and 95 °C for 3LPP. The test time shall be at least 48 hours. The bear metal may be sealed with water resistant paint to reduce rusting. (3) After the conditioning period the samples shall be removed from the bath, dried with paper towel for examination under a stereo microscope with a knife. Press the blade into the interface and rotate it on the longitudinal axis to lift off any of the loose coating. (4) The maximum and average depth of adhesion loss, expressed in millimeters, of the threelayer Polyolefin coating system in the disbonded area shall be measured. 14.11.3 Results and Test Report (1) Identification of test samples; (2) Test temperature and apparatus used; (3) Test results. 14.12

CLEANLINESS OF B LASTING A BRASIVE MATERIAL

This method describes the procedure for monitoring the cleanliness of the blasting abrasives. An increased conductivity level may indicate that an ionic contaminant has been introduced into the blasting material from the pipe surface.

14.12.1 Equipment (1) glass vial (200 -300 ml) (2) conductivity meter 14.12.2 Procedure (1) Measure a 100 ml volume of blasting abrasive material in a glass bottle; (2) add 100 ml deionized or distilled water; (3) cap the bottle and shake for 1 min; (4) see any oil sheen floating on water surface;

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(5) Measure and record the conductivity of the water. The conductivity of the aqueous solution shall be less than 50 μS/cm. If not, the abrasives shall be replaced. If oil sheen on water surface is detected, the abrasives shall also be replaced.

14.12.3 Results and test report (1) Identification of test samples (2) Test apparatus used; (3) Test results. 14.13

MOISTURE CONTENT OF FBE POWDER

14.13.1 Equipment (1) Oven (2) Balance, accurate to 1 mg; (3) Desicator; (4) Sample container 14.13.2 Procedure (1) Weigh the sample container to the nearest mg. Transfer approximately 10 g of FBE powder into the sample container. Weigh the sample container and FBE powder to the nearest mg. (2) Place the sample container with the FBE powder into the oven for 2 h at 105 °C ± 3 °C. (3) Remove the container from the oven, and place it in the desiccators to cool. Weigh the sample container when it has cooled to 20 °C ± 3 °C, and then return it to the desiccators; repeat at intervals of 60 min ± 10 min until two consecutive mass determinations are within 1 mg. (4) Calculate the percentage of moisture using the following formula: Error! Objects cannot be created from editing field codes.

Where wH2O is the percentage moisture, mSI is the initial mass of sample container and FBE powder (g) mSF is the final mass of sample container and FBE powder (g) mC is the mass of sample container (g) The moisture content of the FBE powder can also be determined by using a machine that automatically determines moisture content by mass loss.

14.13.3 Results and test report (1) Identification of test samples; (2) Test procedure; (3) Instrument used; (4) Test results. 14.14

HOT WATER S OAK

The hot water soak test is a good test method to screen candidate FBE and Epoxy coatings.

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14.14.1 Equipment (1) Hot water bath for test temperature <100C, (2) Autoclave for test temperature > 100 C. (3) Pocket knife. 14.14.2 Procedure (1) Prepare three test samples for each coating material. The test samples should be 4”x4”x1/4” to be abrasive blast cleaned to ISO Sa3 cleanliness and all sides are coated without any holiday. All edges and corners are rounded. (2) A 6mm diameter holiday shall be drilled for each of the three samples on the 4”x4” surface only. (3) Immerse the samples in DI water for 20 weeks and take out to examine for any blister and/or holiday formation. If any blister or holiday shows up, the coating is disqualified. (4) Use a knife to peel the coating at the edge of the 6 mm holiday to see any disbondment. If any disbondment can be measured, it is disqualified. 14.14.3 Results and Test Report (1) Identification of the test samples; (2) Test equipment; (3) Test temperature; (4) Any blister and/or holiday formation; (5) Any disbondment; (6) Test report 14.15

COATING A DHESION (NCA) TEST

Pull-off test in accordance with ASTM D4541 or equivalent shall be applied. The popular ASTM D4541 tensile pull-off adhesion test has be used successfully on liquid cured epoxy coatings. For ASTM D4541 test samples, the steel panel size shall be minimum 4” x 4” x1/4” with all edges and corners rounded and abrasive blast cleaned to ISO Sa 3 cleanliness. However, its success on FBE is limited. The new FBE is normally has extremely high interfacial adhesion and the glue failure is the common failure mode for a tensile puff-off test. For water immersed FBE samples, the glue failure is also a common failure mode because of damp surface. Under both conditions, the pull-off adhesion test cannot be used to measure the interfacial adhesion successfully.

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FIELD JOINT COATINGS

For selection of Field joint coatings the Shell DEP 31.40.30.37 “External Field Joint and Rehabilitation Coating Systems for Line Pipe (Amendments/Supplements to ISO 21809-3:2008) is to be use. A list of approved field joint coatings is held at the Technical Centre (Integrity & Operations) and also at Projects Quality Dept. in ADCO.

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REHABILITATION COATINGS

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For selection of Rehabilitation coatings the Shell DEP 31.40.30.37 “External Field Joint and Rehabilitation Coating Systems for Line Pipe (Amendments/Supplements to ISO 21809-3:2008) is to be used for qualification testing of candidate systems. A list of approved rehabilitation coatings is held at the Technical Centre (Integrity & Operations) and also at Projects Quality Department in ADCO.

17

REFERENCES

NOTES: Unless specifically designated by date, the latest edition of each publication shall be used, together with any amendments/supplements/revisions thereto.

SHELL STANDARDS

External Fusion Bonded Epoixy Powder Technical specification or external polypropylene and polyethylene coating for linepipe External Field Joint and Rehabilitation Coating Systems for Line Pipe (Amendments/Supplements to ISO 21809-3:2008) AMERICAN STANDARDS

DEP 31.40.30.32 DEP31.40.30.31 DEP 31.40.30.37

Standard test methods for density and specific gravity (relative density) of plastics by displacement Standard test method for density of plastics by the density-gradient technique

ASTM D792 ASTM D1505

Standard test method for Transition Temperatures of polymers by differential scanning calorimetry

ASTM D 3418

Test method for oxidative-induction time of polyolefins by differential scanning calorimetry

ASTM D3895

Standard practice for measurement of dry film thickness of protective coating systems by destructive, cross-sectioning means Standard Test Method for Conductimetric Analysis of Water Soluble Ionic Contamination of Blasting Abrasives

ASTM D4138

Standard test method for impact resistance of pipeline coatings (falling weight test)

ASTM G 14

Mineral and slag abrasives Cleanliness of recycled ferrous metallic abrasives Ferrous Metallic Abrasive

SSPC-AB1 SSPC-AB2 SSPC-AB3

ASTM D4940

INTERNATIONAL STANDARDS Plastics — Thermoplastic materials —Determination of Vicat softening temperature (VST) Plastics —Determination of tensile properties — Part 2: Test conditions for moulding and extrusion plastics Plastics —Determination of tensile properties — Part 3: Test conditions for films and sheets

Plastics - Determination of the melt mass flow rate (MFR) and the melt volume flow rate (MVR) of thermoplastics Plastics — Methods for determining the density of non-cellular plastics

ISO 306

ISO 527-2 ISO 527-3 ISO 1133 ISO 1183

Plastics — Polyethylene (PE) moulding and extrusion materials — Part 2: specimens and determination of properties Plastics — Polypropylene (PP) moulding and extrusion materials — Part 2: Preparation of test specimens and determination of properties Paints and Varnishes - Determination of film thickness

ISO 1872-2

ISO 2808

Paint and varnishes — Determination of density

ISO 2811

Paints, varnishes and plastics — Determination of non-volatile matter content

ISO 3251

ISO 1873-2

Preparation of steel substrates before application of paints and related products - visual assessment ISO 8501-1

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of surface cleanliness - Part 1: Rust grades and preparation grades of uncoated steel substrates and of steel substrates after overall removal of previous coatings Preparation of steel substrates before application of paints & related products - tests for assessment of surface cleanliness – Part 2: Laboratory determination of chloride on cleaned surfaces

ISO 8502-2

Preparation of steel substrates before application of paints and related products - Tests for the assessment of surface cleanliness – Part 3: assessment of dust on steel surfaces prepared for painting (pressure-sensitive tape method)

ISO 8502-3

ISO 8502-9, Preparation of steel substrates before application of paints and related products — Tests for the assessment of surface cleanliness — Part 9: Field method for the conductometric determination of water-soluble salts

ISO 8502-9

Preparation of steel substrates before application of paints and related products - surface roughness characteristics of blast cleaned steel substrates. Part 1: Specifications and definitions for ISO surface profile comparators for the assessment of abrasive blast cleaned surfaces

ISO 8503-1

Preparation of steel substrates before application of paints and related products - surface roughness characteristics of blast cleaned steel substrates. Part 2: Method for the grading of surface profile of abrasive blast-cleaned steel - comparator procedure

ISO 8503-2

Preparation of steel substrates before application of paints and related products - surface roughness characteristics of blast cleaned steel substrates. Part 3: Methods for the calibration of ISO surface profile comparators and for the determination of surface profile - focusing microscope procedure

ISO 8503-3

Preparation of steel substrates before application of paints and related products - surface roughness characteristics of blast cleaned steel substrates. Part 4: Methods for the calibration of ISO surface profile comparators and for the determination of surface profile - stylus instrument procedure Preparation of steel substrates before application of paints and related products — Surface roughness characteristics of blast-cleaned steel substrates — Part 5: Replica tape method for the determination of the surface profile Preparation of steel substrates before application of paints and related products —Specifications for metallic blast-cleaning abrasives Preparation of steel substrates before application of paints and related products —Specifications for non-metallic blast-cleaning abrasives Preparation of steel substrates before application of paints and related products — Test methods for non–metallic blast cleaning abrasives — Part 6: Determination of water-soluble contaminants by conductivity measurement Plastics — Differential scanning calorimetry (DSC )

ISO 8503-4

ISO 11357-7

Plastics — Determination of water content

ISO 15512

Petroleum and natural gas industries – external coatings for buried or submerged pipelines used in pipeline transportation systems –Part 1: Polyolefin coatings (3-layer PE and 3-layerPP)

ISO 21809-1

Fusion Bonded Epoxy Coating

ISO 21809-2

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ISO 11124 ISO 11126 ISO 11127-6



ISO 8503-5

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Specification for External Pipeline Coatings

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