EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

Document No : GF-WP1-E-10-0252

Revision : A

Page : Page 2 of 14

REVISION HISTORY

REV. DATE DESCRIPTION OF CHANGE

A 18-Jan-15 ISSUED FOR APPROVAL

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

Document No : GF-WP1-E-10-0252

Revision : A

Page : Page 3 of 14

TABLE OF CONTENTS

1.0 GENERAL ....................................................................................................................... 4

1.1. Introduction .................................................................................................................... 4

1.2. Scope ............................................................................................................................ 5

1.3. Definition ....................................................................................................................... 5

1.4. Particular Definitions ...................................................................................................... 6

1.5. Abbreviation .................................................................................................................. 7

2.0 STANDARDS, CODES AND PROJECT DOCUMENTS ................................................. 8

2.1. International Standards and Codes................................................................................ 8

2.2. Other References .......................................................................................................... 9

2.3. Order of Precedence ..................................................................................................... 9

2.4. Language and Units of Measurements .......................................................................... 9

3.0 DESIGN AMBIENT CONDITIONS ................................................................................ 10

4.0 PROTECTION CRITERIA ............................................................................................. 10

5.0 CATHODIC PROTECTION FOR PIPELINES ............................................................... 10

5.1. ICCP System ............................................................................................................... 10

5.2. SACP System .............................................................................................................. 12

5.3. Interaction and induced effects .................................................................................... 13

5.4. Electrical Continuity ..................................................................................................... 14

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

Document No : GF-WP1-E-10-0252

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1.0 GENERAL

1.1. Introduction

The Development and Production Service Contract (DPSC) for the Garraf Contract

Area was signed between South Oil Company (SOC), PETRONAS Carigali Sdn. Bhd,

Japan Petroleum Exploration Co. Ltd and North Oil Company. Garraf field takes its

name from the Shatt Al Garraf waterway, a tributary of the River Tigris. It is one of a

group of undeveloped fields sometimes referred to as the Garraf axis fields. The others

include Nasiriyah and Rafidain. Garraf Field is situated in the Southern part of Iraq, in

the ThiQar Governorate, some 5km Northwest of Al Refaei city and 85km North of

Nasiriyah. Garraf is an anticlinal structure aligned Northwest– Southeast, about 31km

long and 10km wide.

Figure 1: Location of Garraf Field in Southern Iraq (Source: Public Domain)

Two proven formation in Garraf are being considered for development, namely Mishrif

and Yamama. Garraf Oil Field is expected to be developed in 2 phases;

i. Phase 1 - First Commercial Production (FCP), and

ii. Phase 2 - Final Field Development (FFD).

The Mishrif formation production capabilities will be enhanced in phases by

development of additional Wellpads and gathering facilities. This PROJECT’s main

objective is to sustain the FCP production capacity of 100,000 BOPD till the field

reaches the PPT target in 2017 by phased development.

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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The scope of this PROJECT consider development of WP-C, D and J which consists of

new production wells and tie-in to the existing facilities at Wellpad A, Wellpad F and

GIFT

1.2. Scope

This document outlines the Cathodic Protection Design Basis for underground pipelines

as per the below table for EPCC of Oil Gathering Facilities (Phase-1 Offsite 3) for

PETRONAS Carigali Iraq Holding B.V. Garraf Operations project.

Pipeline to be protected under this project scope is as follows:

Pipe dia.

（Inches）

From To Coating Approx. length

（Km）

18” WP-C GIFT-IM 3LPE 3.2

18” WP-J WP-F 3LPE 3.72

The trunklines connect between the various wellpads facilities shall be constructed in

phases. The trunklines shall be cathodically protected via an impressed current

cathodic protection (ICCP) system existed in the GIFT as the GRAAF FINAL

DEVELOPMENT PLAE (GFDP); the trunklines shall be protected by Temporary

Sacrificial Anode CP system till the commissioning of the ICCP system. Standard Test

Post (STP) shall be installed for all pipelines at regular intervals to monitor the potential

of the trunklines with respect to the Reference Electrode.

1.3. Definition

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

PROJECT : Oil Gathering Facilities (Phase 1 – Offsite 3) For

PETRONAS Carigali Iraq Holding B.V. Garraf

Operations

COMPANY : PETRONAS Carigali Iraq Holdings BV (PCIHBV)

EPC CONTRACTOR : GRAND ENERGY DEVELOPMENT LIMITED.

MANUFACTURER/

SUPPLIER/VENDOR

: Party/(s), which manufactures and/or supplies

material, equipment and services to perform the

duties as specified by EPC CONTRACTOR /

COMPANY in the scope of supply

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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SUBCONTRACTOR/

SUBVENDOR

: The party(s) which carries out all or part of the

design, procurement, installation and testing of the

system(s) as specified by the EPC CONTRACTOR

TECHNICAL NOTES

: A Deviation requested by the SUBCONTRACTOR,

EPC CONTRACTOR or MANUFACTURER, usually

after receiving the contract package or purchase

order. Often, it refers to an authorization to use,

repair, recondition, reclaim, or release materials,

components or equipment already in progress or

completely manufactured but which does not

comply with project requirements. TECHNICAL

NOTES are subject to COMPANY approval

Shall : Indicates a mandatory requirement

Should : Indicates a strong recommendation to comply with the requirements of this document

1.4. Particular Definitions

ANODE - The electrode of an electrochemical cell at which oxidation occurs. Electrons

flow away from the anode in the external circuit. Corrosion usually occurs and metal

ions enter solution at the anode.

CATHODE - The electrode of an electrochemical cell at which reduction is the principal

reaction. Electrons flow toward the cathode in the external circuit.

CATHODIC POLARIZATION - The change of electrode potential in the active

(negative) direction caused by current across the electrode/electrolyte interface.

CATHODIC PROTECTION - A technique to reduce the corrosion of a metal surface by

making that surface the cathode of an electrochemical cell.

CONTINUTY BOND - A connection, usually metallic, that provides electrical continuity

between structures that can conduct electricity.

CORROSION POTENTIAL (Ecorr) - The potential of a corroding surface in an

electrolyte relative to a reference electrode under open-circuit conditions (also known

as rest potential, open-circuit potential, or freely corroding potential).

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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ELECTRICAL ISOLATION - The condition of being electrically separated from other

metallic structures or the environment.

SACRIFICIAL ANODE - A metal that provides sacrificial protection to another metal that

is more noble when electrically coupled in an electrolyte. This type of anode is the

electron source in one type of cathodic protection.

IMPRESSED CURRENT - An electric current supplied by a device employing a power

source that is external to the electrode system. (An example is direct current for

cathodic protection.)

IR DROP - The voltage across a resistance in accordance with Ohm’s Law.

REFERENCE ELECTRODE- An electrode whose open-circuit potential is constant

under similar conditions of measurement, which is used for measuring the relative

potentials of other electrodes.

STRAY CURRENT CORROSION - Corrosion resulting from current through paths other

than the intended circuit, e.g., by any extraneous current in the earth.

1.5. Abbreviation

Dry Film Thickness DFT

Polypropylene PP

Polyethylene PE

Cross Linked Poly Ethylene XLPE

Three Layer Poly Ethylene Coating 3LPE

Impress current cathodic protection ICCP

Sacrificial anode cathodic protection SACP

Standard Test Post STP

Cathodic Protection CP

Temporary Cathodic Protection System TCP

Permanent Cathodic Protection System PCP

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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Road Crossing Test Post RDXTP

Canal Crossing Test Post CXTP

Polarization Coupon Test Post PCTP

Foreign Pipeline Bond Box FBB

Equi-Potential Bond Box EBB

Copper-Copper Sulphate Cu/Cuso4

Inlet Manifold IM

Direct Current Voltage Gradient DCVG

Line Current Test Post LCTP

Magnesium Mg

Mixed Metal Oxide MMO

National Association of Correction Engineers NACE

Poly Vinyl Chloride PVC

International Standards Organization ISO

Alternating Current AC

Direct Current DC

First Commercial Production FCP

Transformer Rectifier Unit TRU

Final Field Development FFD

2.0 STANDARDS, CODES AND PROJECT DOCUMENTS

2.1. International Standards and Codes

Unless otherwise specified in Data Sheets / Specifications, the latest edition of following

code standards as applicable at the time of order shall be followed. In addition to below,

codes and standards mentioned in individual equipment specification shall also be

complied:

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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BS 7361 Part 1 Cathodic Protection Code and Practice for Land

and Marine Application

NACE SP 0177 Mitigation of Alternating Current and Lighting

Effects on Metallic Structures and Cathodic

Protection System.

DIN/VDE 0150 Protection against Corrosion Due to Stray

Current from DC Installations.

NACE SP0192 Monitoring Corrosion in Oil and Gas Production

with Iron Counts

NACE SP0169

Control of External Corrosion on Underground and Submerged Metallic Piping System

ISO 15589-1

Cathodic Protection of Pipeline Transportation Systems

NACE SP0286 Electrical Isolation of Cathodically Protected Pipelines

DNV RP B 401 Cathodic Protection Design

NACE SP 0572 Design, Installation, Operation and Maintenance of Impressed Current Deep Anode Beds

2.2. Other References

Specifications, Data sheets, Calculation and drawings.

2.3. Order of Precedence

In case of any conflict amongst the various codes, standards and the project

documents, the following order of precedence shall be applicable:

Laws and regulations of Iraq

Data sheets

Cathodic Protection Specification

Cathodic Protection Design Basis

International Codes and Standards

2.4. Language and Units of Measurements

The governing language of contract shall be English language. All notices,

correspondences, information, literature, data, manuals and other documents required

under this contract shall be in the English language.

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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As a rule, the SI unites shall be used. However, for some main parameters such as

pressure, flow rate and temperature, both SI and Imperial unites shall be adopted (the

second ones will be included in brackets). As an exception for SI unit for pressure, bar

shall be used instead of Kappa. MMSCFD will be used for hydrocarbon gas flow.

Furthermore, pipe size will be inches, dynamic viscosity in centipoises and kinematic

viscosity in centistokes.

For detailed unit of measurement refer section 3.0 of Design Basis Memorandum

(General) Doc no GF-WP1-G-10-0251.

3.0 DESIGN AMBIENT CONDITIONS

For Detail Engineering Design Data, refer section 4.0 of Design Basis Memorandum

(General) Doc no GF-WP1-G-10-0251.

4.0 PROTECTION CRITERIA

Cathodic Protection system shall be designed to achieve polarized (Instant-Off)

protective potentials in the range of -850mV to -1200mV as measured against a

saturated Copper/Copper Sulphate Reference Electrode contacting the electrolyte and -

900mV to -1150mV as measured against a saturated Silver/Silver Chloride Reference

Electrode Contacting the Electrolyte.

Alternatively, a minimum of 100mV Cathodic Polarization as measured between the

structure surface and a stable reference electrode contacting the electrolyte can also be

considered as a protection criteria (NACE SP-0169 section 6) subject to COMPANY

approval. Formation or decay of polarization can be measured to satisfy this criterion.

The mean change of potential at any part of another pipeline and installation from

interference should not cause potentials outside the protective potential criteria as

stated above. In the event of interference resulting in the CP criteria not being met,

remedial action shall be taken to eliminate the interference.

15VAC (RMS) open circuit or a source current capacity of 5mA or more (as per NACE

SP-0177 section 5.2.1.1) are considered to constitute an anticipated shock hazard.

5.0 CATHODIC PROTECTION FOR PIPELINES

5.1. ICCP System

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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5.1.1. ICCP System description

The pipelines shall be protected by the Impressed Current Cathodic Protection (ICCP)

system, ICCP will be applied to buried pipelines connecting from Well Pad C to GIFT

and Well pad J to F.

The ICCP system consists of cathodic protection power source units TRU, Deep well

anode groundbed, cable, junction box, reference electrode and test post, etc. The

design life of cathodic protection system be shall same as the pipelines.

The existing cathodic protection station (CPS-N1) which is installed nearby GIFT-IM

Manifold during Phase 2 has sufficient capacities to accommodate the CP system for

this project. Refer CP design calculation report GF-WP1-E-13-2003 for details.

The power source unit of the cathodic protection station CPS-N1 has existing

Transformer rectifier Unit of 400 volt AC, 50 Hz, oil cooled type, which is proposed to

power the CP system under the scope of work.

The existing CPS-N1 deep well anode groundbed of MMO coated Titanium anode with

the dimensions of anode φ25.4mm x 1000mm, and with 1x16mm2KYNAR /HMWPE

cable, which is installed at depths of 58m and at least 50 m perpendicular distance from

pipelines shall be used for the new CP system.

New potential test post shall be installed at every 1km along the pipelines and at the

place of every foreign pipeline crossing the pipelines. It is not necessary to install test

post when it comes at cross open excavation.

In order to achieve Cathodic Protection of the proposed buried pipelines, effective

isolation shall be mandatory to minimize or reduce leakage of cathodic protection

current to other metallic structures. All the pipelines shall be isolated from other

structures by the installation of the new isolating joints at either end.

The pipeline shall also be electrically isolated from the concrete foundations at Tap-Off/

Tie-OFF, valves, vents, chambers, stacks, scrape, traps, casing, earthing and all other

locations.

At every isolation joint location, new test post shall be installed.

Bond boxes are proposed to bond all the U/G pipelines intended for CP at strategic

locations.

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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Equipotential bond boxes shall be provided at every location where the pipelines are

parallel with each other every 5 km.

5.1.2. ICCP System Design Parameters

Design life: 25 years

Diameter & length: Varies (refer Section 1.2)

Coating: 3LPE

Coating Breakdown: Included in current density

Base Current Density: 0.25mA/m2 for 3LPE coated Pipeline at 30 Degree.

Temperature Correction: 25% per 10 Degree of temp above 30℃

Operating Temperature: 65 and 70 Degree for Trunklines

Anode type: MMO Tubular Anodes

Soil resistivity: 20 Ohm-m

5.2. SACP System

5.2.1. SACP System description

Temporary cathodic protection system utilizing sacrificial anodes shall be considered for

the protection of trunklines during the construction phase, till the commissioning of the

permanent cathodic protection system;

New Pre-packed sacrificial anodes shall be installed horizontally / vertically in soil at a

distance of 1.5-3m from pipe and at pipe invert levels;

New test posts (TP) shall be provided for monitoring purposes and termination of CP

cables (anode tail cable). All anodes shall be connected to the trunkline through the test

post;

At all test posts, two cables shall be connected to pipeline. Trunkline to cable

connection shall be done by pin brazing / thermite welding technique;

The anode for temporary cathodic protection shall be magnesium alloy anode. The

anode material shall be M1C type in ASTM B843 and limit life shall be 2 years.

EPCC Of Oil Gathering Facilities (Phase-1 Offsite 3)

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More details of the cathodic protection system shall be as per GF-GEN-E-SP-1003 CP

System Specification.

5.2.2. SACP System Design Parameters

Design life: 2 years

Diameter & length: Varies (refer Section 1.2)

Coating: 3LPE

Coating Breakdown: Included in current density

Base Current Density: 0.05mA/m2 (Refer CI：4.3.1.2，BS-7361 Part-1)

Temperature Correction: 25% per 10 Degree of temp above 30℃

Operating Temperature: 65 and 70 Degree for Trunklines

Anode type: High Potential Magnesium Anodes

Soil resistivity: 20 Ohm-m

5.3. Interaction and induced effects

a) Foreign service crossings

At all locations where a buried pipeline crosses existing foreign services, facilities shall

be required to allow bonding between the buried lines and the Foreign Service.

No cable connections shall be made to foreign services without written approval from

the Company.

Bonding facilities shall include resistors and current measuring shunts.

Given the high integrity of the applied coatings on the new buried lines, bonding ·to

foreign pipelines shall be kept to an absolute minimum. This shall avoid the possibility

of over protection from other systems that may be providing high current outputs to old

or poorly coated pipeline systems.

b) Crossings/Parallelisms

Alternating currents induced in pipelines running parallel with overhead power lines or

running nearby can generate voltages that may be harmful for the personnel working on

the pipeline and can also cause corrosion. Such voltages require mitigation.

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Mitigation study and results of mitigation study shall be indicated in the applicable

deliverables.

5.4. Electrical Continuity

For cathodic protection systems protecting more than one pipeline, suitable electrical

cross bonding shall be carried out at suitable intervals along parallelisms. Bonding

should be carried out in accordance with NACE RP0169. The cables from the separate

pipelines shall be brought above ground and joined in a suitable test post.