dgs-pu-302-rev-0

Abu Dhabi Oil Refining Company

PIPELINE ISOLATING JOINTS DGS-PU-302 Rev-0 March 2006

Takreer DGS-PU-302-Rev-0 March-2006 Printed 20-Apr-09 08:44:30 Initials of 15

PIPELINE ISOLATING JOINTS

Amendment History

No Date Amendment Description Proposed Approved Incorporated

DGS History

0 March 2006 DGS-PU-302-Rev-0 Previous Project / Lessons Learnt Incorporated

AH/DDC ETSDM / EPDM

No Date Description Source Reviewed Approved

DGS-PU-302 Rev-0




TABLE OF CONTENTS

1.0 GENERAL ................................................................................................................................3 1.1 INTRODUCTION.............................................................................................................3 1.2 PURPOSE.......................................................................................................................3 1.3 DEFINITIONS .................................................................................................................3

2.0 CODES AND STANDARDS .....................................................................................................3 3.0 REFERENCE DOCUMENTS ...................................................................................................4 4.0 DOCUMENT PRECEDENCE...................................................................................................5 5.0 SPECIFICATION DEVIATION/CONCESSION CONTROL ......................................................5 6.0 QUALITY ASSURANCE/QUALITY CONTROL ........................................................................5 7.0 SITE CONDITIONS..................................................................................................................6 8.0 DESIGN AND FABRICATION...................................................................................................6

8.1 WELDING AND NDT PROCEDURES ............................................................................7 9.0 MATERIAL REQUIREMENTS ..................................................................................................8

9.1 INSULATING MATERIAL ................................................................................................8 10.0 INSPECTION AND TESTING...................................................................................................8

10.1 HYDROSTATIC TESTING ..............................................................................................9 10.2 ELECTRIC TEST ..........................................................................................................10

11.0 COATINGS .............................................................................................................................10 12.0 MARKING............................................................................................................................... 11 13.0 PREPARATION FOR SHIPMENT .......................................................................................... 11 14.0 MATERIAL CERTIFICATION AND TRACEABILITY...............................................................12 15.0 VENDOR DATA REQUIREMENTS LIST (VDRL)...................................................................12 ADDENDUM SHEET .......................................................................................................................15

List of Authorized Signatures/ Initials

DGS Discipline Committee Member, ADRD ------------------------------

DGS Discipline Committee Member, RRD ------------------------------

DGS Discipline Committee Member Leader, E&PD Abdul Hakim (AH)

Engineering & Technical Services Manager, E&PD Quazi Abdul Matin (QAM)

Engineering & Projects Division Manager, E&PD Mohamed Al Yabhouni (MAY)




1.0 GENERAL

1.1 INTRODUCTION

The specification gives the minimum technical requirements for the design, manufacture, testing, inspection, coating/painting and supply of monolithic isolating joints to be used for non-sour, liquid service on onshore pipelines.

1.2 PURPOSE

This specification supplements the codes listed in Section 2.0 of this specification.

1.3 DEFINITIONS

For the purpose of this specification, the following definitions shall apply:

1.3.1 CONCESSION REQUEST - A deviation requested by the CONTRACTOR / SUBCONTRACTOR or VENDOR / SUBVENDOR, usually after receiving the contract package or purchase order. Often, it refers to an authorisation to use, repair, recondition, reclaim, or release materials, components, or equipment already in progress or completely manufactured but which does not meet or comply with COMPANY requirements. A CONCESSION REQUEST is subject to COMPANY approval.

1.3.2 SHALL - The use of the word “shall” indicates a mandatory requirement.

1.3.3 SHOULD - The use of the word “should” indicates a strong recommendation to comply with the requirements of this document.

2.0 CODES AND STANDARDS

It shall be the CONTRACTOR’s, VENDOR’s, SUBCONTRACTOR’s and or SUBVENDOR’s responsibility to be or to become knowledgeable of the requirements of the referenced codes and standards.

The following codes and standards, to the extent specified herein, form a part of this specification. When an edition date is not indicated for a code or standard, the latest edition in force at the time of contract award shall apply.

American Society of Mechanical Engineers (ASME)

ASME B16.9 Factory-Made, Wrought Steel-Butt Welded Fittings

ASME BPV Section V Boiler and Pressure Vessel Code: Non-destructive Examination

ASME BPV Section VIII Boiler and Pressure Vessel Code: Division I - Pressure Vessels




ASME BPV Section IX Boiler and Pressure Vessel Code: Welding and Brazing Qualifications

ASME B31.4 Pipeline Transportation System for Liquid Hydrocarbons and Other Liquids.

American Petroleum Institute (API)

API 5L Specification for Line Pipe

API 1104 Welding of Pipelines and Related Facilities

American Society for Testing Material (ASTM)

ASTM A370 Mechanical Testing of Steel Products

ASTM D695 Test Method for Compressive Properties of Rigid Plastics.

ASTM E92 Standard Test Methods for Vickers Hardness of Metallic Materials

National Association of Corrosion Engineers (NACE)

NACE RP 0188 Discontinuity (Holiday) Testing of Protective Coating

NACE RP 0286 Electrical Isolation of cathodically protected pipelines.

Manufacturers Standardisation Society of Valve Fitting Industry, Inc. (MSS)

MSS SP-75 High -Test Wrought, Butt-Welded Fittings.

International Organisation for Standards (ISO)

ISO 9001 - 2000 Quality Management System Requirements

ISO 9004 - 2000 Quality Management Guidelines for Performance Improvement System

ISO 9011 Guidelines for Quality and/or Environmental System Auditing

ISO 10474 Steel and Steel Products - Inspection Documents.

ISO 8501-1 Preparation of Steel Substrates Before Application of Paints and Related Products-Visual Assessment of Surface Cleanliness Part 1.

3.0 REFERENCE DOCUMENTS

The following reference documents, to the extent specified herein, form part of this specification. When an edition date is not indicated for a document, the latest edition in force at the time of contract award shall apply.




Design General Specifications:

DB-PU-401 Pipeline Engineering Design Basis

DB-PU-001 Process Design Basis

DGS-PU-319 Pipeline Welding

DGS-MX-001 Design General Specification/Procedures (Painting)

DGS-PU-307 HFW Line Pipe

DGS-PU-320 Seamless Line Pipe

DGS-MY-003 Cathodic Protection System for Buried Pipeline

DGS-PU-308 External Three Layer Polyethylene (3LPE) Coating for Line Pipe

DGS-PU-315 Internal Linings

DGS-PU-322 External Three Layer Polypropylene (3LPP) Coating for Line Pipe

Applicable project line pipe specification shall be referred.

4.0 DOCUMENT PRECEDENCE

The CONTRACTOR and or VENDOR shall notify the COMPANY of any conflict between this specification, the related data sheets, the Codes and Standards and any other specifications noted herein. Resolution and/or interpretation precedence shall be obtained from the COMPANY in writing before proceeding with the design or manufacture.

In case of conflict, the order of precedence shall be stated in the AGREEMENT or other PROJECT documents as applicable.

5.0 SPECIFICATION DEVIATION/CONCESSION CONTROL

Any technical deviations to the Specifications and its attachments including, but not limited to, the Data Sheets and Narrative Specifications shall be sought by the CONTRACTOR / VENDOR / SUBVENDOR only through CONCESSION REQUEST format. CONCESSION REQUESTS require COMPANY’S review/approval prior to the proposed changes being implemented. Technical changes implemented prior to COMPANY approval are subject to rejection.

6.0 QUALITY ASSURANCE/QUALITY CONTROL

VENDOR’S proposed quality system shall fully satisfy all the elements of ISO 9001 - 2000 and ISO 9004 - 2000. The quality system shall provide for the planned and




systematic control of all quality-related activities performed during design, development, production, installation or servicing (as appropriate to the given system).

Implementation of the system shall be in accordance with the CONTRACTOR’S Quality Manual and Project Specific Quality Plan, which shall both together with all related/referenced procedures, be submitted to COMPANY for review, comment and approval as required by purchase/contract documents.

Material certification and traceability shall be in accordance with para. 14.0 and 15.0.

7.0 SITE CONDITIONS

Site conditions shall be in accordance with Process Design Basis, document number DB-PU-001.

8.0 DESIGN AND FABRICATION

The isolating joint shall be composed as follows:

• Two spools, internally coated, each consisting of a pipe section with a bevelled end for direct welding to the pipeline. The pipe section shall be in accordance with Design General Specification of the connected line pipe. A length of 50 mm at each end shall be left uncoated to allow welding to the pipeline.

• Forged steel pieces welded to the other end of each spool material, which shall be compatible to pipeline material.

• Insulation and filler materials for electrical isolation between the two associated spools.

• Two cable connection lugs, equidistant from the end of the pipe section and the joint, externally welded on doubler plate. One set of lugs is intended for electrical measurement, the other is intended for a surge diverter installation.

• A forged steel retaining casing for strength connection of the two spools.

• A double set of ring seals for pipeline internal pressure containment.

• VENDOR shall confirm the heat generated by heat treatment or welding is not detrimental to the isolating and filler materials and internal coating.

Design of isolating joint shall be compatible with design code adopted for the pipeline in which it is installed. For isolating joint, Design factor of 0,5 with minimum Corrosion allowance as specified in purchase order shall be considered.

Designs shall be offered for boltless, monobloc couplings of isolating joints for onshore applications. Isolating joints shall be installed above ground.




Proven history of successful installations is a mandatory requirement for each type and size of joint offered. VENDOR shall provide details with its proposal to company.

Details of independent laboratory tests shall be submitted for standard high pressure joints, including details of torsion testing under pressure.

The isolating joint assembly, shall be capable of withstanding a maximum bending moment during hydrostatic testing equivalent to that required to induce a bending stress of 75% SMYS in the matching line pipe. The isolating joint shall be capable of withstanding a maximum torsion stress of 5 percent SYMS in the matching line pipe.

The joints shall be designed to pass all types of pigs. Overall minimum length of isolating joint shall be as per following:

2600 ± 25mm for 18" in diameter and above.

1200 ± 10 mm for 16" in diameter and below.

The joints shall be capable of withstanding the effects of a humid salt laden atmosphere onshore without loss of performance.

Isolating joint design and materials shall be capable of being vacuum tested. Test pressure shall be consistent with that determined for vacuum drying.

The joint between pipe sections and main forgings shall be a full penetration butt weld type.

Pipes to which the isolating joint pup pieces will be welded will be manufactured in accordance with the Design General Specifications for connected Line Pipe.

The isolating joint components shall be manufactured by forging.

The internal diameter of each isolating joint shall not be less than the internal diameter of the pipe to which it is to be welded. For a distance 100mm from welding ends, the internal diameter shall not deviate by more than ± 1.5 mm from nominal internal diameter of the pipeline.

Bevel ends shall be in accordance with API 5L.

8.1 WELDING AND NDT PROCEDURES

All welding, including weld repairs shall be performed in accordance with Design General Specification DGS-PU-319 and welders/operators qualified in accordance with ASME BPV Code Section IX and API 1104.

Welding procedure specifications, procedure qualification records, non-destructive testing (NDT) procedures and any other document required by this specification shall be submitted following the award of a purchase order. The written approval of the COMPANY must be obtained before any welding may commence.




Welds made to assemble individual components shall be post weld heat treated in accordance with ASME BPV Code Section VIII if the wall thickness exceeds 25 mm. VENDOR shall confirm that heat generated by the heat treatment is not detrimental to the isolating and filler material. Length of isolating joint may be increased if this is not the case.

VENDOR shall submit a complete manufacturing procedure with his proposal.

9.0 MATERIAL REQUIREMENTS

VENDOR shall submit to COMPANY for approval, a complete list of specifications for the materials proposed for the manufacture of the isolating joints.

Materials shall be suitable for the required service as stated in the purchase requisition, and tested in accordance with this document.

The materials used for the manufacture of the isolation joints shall conform with the requirements of the line pipe with which they are to be installed. Carbon steel used in the manufacture of isolating joints shall be fully killed.

Forging shall have following chemical restriction:

Carbon 0.23%

Manganese 1.2% max

Carbon Equivalent 0.42 max

9.1 INSULATING MATERIAL

Only continuously moulded precision viton seals resistant to explosive decompression shall be used. Minimum hardness of seals shall be 75 Shore D. All dimensions shall be in accordance with Manufacturer’s standard. Details of the insulating materials, including dielectric strength, compressive strength, dimensions and suitability for use at the design temperature and pressure and long term exposure to the fluid transported shall be included in VENDOR proposal.

10.0 INSPECTION AND TESTING

Inspection shall be carried out in accordance with VENDOR's Quality Plan, which shall require COMPANY approval. The plan shall include provisions for material test report certificates and traceability of all source materials.

All isolating joints shall be visually examined and shall be checked for compliance with the dimensional requirements.

Base metal, weld metal and heat-affected zone shall have a maximum hardness of 325 HV10.




Base metal hardness readings shall be made as per ASTM E92 on each heat lot of fittings at 5 random locations.

Testing of insulating materials shall be in accordance with ASTM D695.

Tensile testing shall be in accordance with MSS SP-75.

All butt welds shall be 100 percent radiographed.

The welding ends of each isolation joint shall be 100 percent ultrasonically examined over the entire circumference for a distance of 25 mm from each end.

All other welds and bevels ends shall be Magnetic Particle Inspected (MPI).

Forgings shall be subjected to 100 percent surface examination by MPI.

No repairs shall be permitted to joints that have failed any of the tests outlined in this section.

Acceptance and rejection criteria are reported here below:

Ultrasonic testing shall be in accordance with ASME BPV Code Section V, Articles 5 & 23.

Radiography shall be in accordance with ASME BPV Code Section V, Articles 2 & 22.

Magnetic Particle Inspection shall be the wet method and in accordance with ASME BPV Code Section V, Article 7 & 25.

Results shall be reviewed, interpreted, and evaluated in accordance with the following criteria:

X-RAY: ASME BPV CODE SECTION VIII DIVISION ONE SECTION UW51.

MPI: ASME BPV CODE SECTION VIII DIVISION ONE APPENDIX 6.

U.T.: FOR WELDS, ASME BPV CODE SECTION VIII DIVISION ONE APPENDIX 12.

U.T.: FOR FORGING, ASME BPV CODE SECTION VIII DIVISION 2 SECTION AM 203.2 (C).

10.1 HYDROSTATIC TESTING

10.1.1 Hydrostatic Strength Test

Each isolating joint shall be hydrostatically tested at a pressure, which will produce a hoop stress of 95 percent SMYS with the isolating joint in an unrestrained condition. Pressure shall be held for 4 hours. There shall be no leakage or loss of pressure.




10.1.2 Hydrostatic Fatigue Test

a. Test Pressure: 80 percent of Hydrostatic Pressure Test

Test Duration: 1 hr.

b. Reduce pressure to atmospheric level.

c. This test shall be carried out for 5 cycles, holding for five minutes for each cycle.

The above tests shall be carried out with bending moment applied as per Section 8.0 of this document.

d. The temperature difference between isolating joint and test liquid shall not be greater than 10oC. There shall not be water leakage or permanent distortion.

10.1.3 Air Leak Test

After hydrostatic testing, all isolation joints shall be leak tested with air at 10 barg for 10 minutes. The tightness shall be checked by immersion or with a frothing agent. No leakage will be accepted.

10.1.4 Torsional Test

One joint of each size shall be subjected to torque sufficient to introduce a torsional stress of 5% SMYS in the adjoining Pup Piece. There shall be no relative rotational movement of the Pup Piece on completion of test.

10.2 ELECTRIC TEST

All isolating joints shall be electrically tested.

Electrical checks, to be done after the hydrostatic pressure test, shall be carried out in the following sequence:

• A voltage of 1500 V (AC) at 50Hz shall be applied across the joint for 5 minutes. There shall be no breakdown, flashover and reduction in electrical resistance during this period.

• A voltage of 1000 V (DC) shall be applied across the joint in a dried condition. The resistance shall be at least 1 mega-ohm.

11.0 COATINGS

The isolating joint shall be coated internally to prevent electrical bridging of the two spools through the transported fluid. The joint shall be coated externally. The internal and external coatings shall terminate 50 mm from the joint ends.




All surfaces to be coated shall be blast cleaned to ISO 8501-1 grade SA 21/2. The internal coatings shall consist of an amine-cured epoxy, to a minimum dry film thickness of 300 microns applied in two coats. The application shall be in strict accordance with the coating supplier’s specification.

Note: Metallic pigmented coatings shall not be used.

Following the hydrostatic pressure test and electrical checks, the coatings shall be subject to holiday detection using a wet sponge tester set at 60 volts and tested in accordance with NACE RP0188 Section 3. The acceptance level shall be zero holidays.

The external coating shall comply with Design General Specification DGS-MX-001.

12.0 MARKING

Isolating joints shall be paint stencilled in 20 mm high or larger letters on the outside of the pipe 100 mm from the end using a weather resistant paint of contrasting colour with the following information:

• Project Name

• Manufacturer

• Purchase Order Number and Item Number

• Nominal wall thickness at bevel ends

• Nominal size

• Material Grade

• Design pressure/Hydrostatic Test Pressure

• Grade of steel and heat number of pipe sections

• Serial number

• Pressure rating class

• Year of Manufacture

13.0 PREPARATION FOR SHIPMENT

The isolating joint assemblies shall be packaged so as to prevent damage during shipping.

VENDOR shall submit with his proposals the following information:




• Protection of weld bevels against damage during shipment.

• Physical protection of the test point connections.

• External protection against corrosion.

• Protection from damage during shipment.

Only those isolating joints, which have been inspected and certified by purchaser’s inspector shall be shipped.

14.0 MATERIAL CERTIFICATION AND TRACEABILITY

Material Test Certificates and Manufacturer Test Reports shall be traceable within the VENDOR Fabrication Book, which shall be part of the QC Data Book.

The pressure containing and load bearing/stressed materials shall be fully covered by the Material Test Certificates, which shall bear Equipment Tag Numbers, Purchase Order Numbers and any other Purchase Order requirements.

For quality assurance requirements and inspection requirements, refer to the Purchase Order and its referenced documents.

15.0 VENDOR DATA REQUIREMENTS LIST (VDRL)

The CONTRACTOR/VENDOR shall submit certification and inspection documents to the COMPANY’s representative as specified in the purchase order. Mutual agreement on scheduled submittal of drawings and engineering data shall be an integral part of any formal Purchase Order.

All documents, drawing text and dimensions shall be expressed in English language and shall be in the metric system.

Comments made by CONTRACTOR on drawing submittal shall not relieve VENDOR or SUBVENDORS of any responsibility in meeting the requirements of the specifications. Such comments shall not be construed as permission to deviate from requirements of the Purchase Order unless specific and mutual agreement is reached and confirmed in writing.

Each drawing shall be provided with a title block in the bottom right-hand corner incorporating the following information:

• Official trade name of the VENDOR.

• VENDOR’S drawing number.

• Drawing title giving the description of contents whereby the drawing can be identified.




• A symbol or letter indicating the latest issue or revision.

• PO number and item tag numbers.

Revisions to drawing shall be identified with symbols adjacent to the alterations, a brief description in tabular form of each revision shall be given, and if applicable, the authority and date of the revision shall be listed. The term "Latest Revision" shall not be used.

The VENDOR shall submit certification and inspection documents to the COMPANY’s representative as specified in the purchase order. Documents shall include the following as a minimum:

• Material certificates stating mechanical properties and chemical analysis for all materials used in the fabrication of the isolating joint assemblies. Certified mill test reports shall be furnished for all material.

• Material certificates for steel parts 3.1.C to ISO 10474

• Quality Plan

• Production Schedule

• Manufacturing Procedure

• Marking Procedure

• Inspection and Testing Plan

• Approved Welding Procedures

• Welding Procedure Qualification and Welder Qualification Certificates

• Heat Treatment Procedure and Records

• Mechanical Test Reports

• NDT reports.

− Hydrostatic fatigue test reports

− Electric test reports

− Cyclic test reports

− Leak test reports

• All design calculations.




• Dimensional drawings and cross section details.

• Parts List with corresponding Assembly Drawings

• General Arrangement Drawings

• Final Inspection Report

• Certificate of Conformance/ Dimensional Check Reports

• Verification Certificates for Standard Compliance

• Installation, Operation & Maintenance Manual

• All Concession Requests




ADDENDUM SHEET

All revisions to this DGS subsequent to the issue of Rev Zero shall be recorded in this addendum sheet and shall be incorporated into the DGS in the next revision.

Date Proposed Revision Remarks