Engineering Standard

SAES-X-700 27 December 2017

Cathodic Protection of Onshore Well Casings
Document Responsibility: Cathodic Protection Standards Committee

Contents

1 Scope ............................................................... 3
2 Conflicts and Deviations..................................... 5
3 References ....................................................... 5
4 Definitions and Abbreviations ............................. 7
5 Design Review and Approval ............................13
6 Design Technical Requirements ........................16
7 Installation, Records, Commissioning,
and Inspection..................................................40
Revision Summary..................................................41

Appendix 1 - Design Quality Assurance Check List ...42

Appendix 2 - Drill Stem and Test Anode
Resistance Measurements ..................43
Appendix 3 - Recommended Procedures .................46

Previous Issue: 7 November 2013 Next Planned Update: 27 December 2020

Page 1 of 49
Contact: Mahrous, Husain M. (mahroohm) on phone +966-13-8809631

©Saudi Aramco 2017. All rights reserved.

Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

DETAILED INDEX OF CONTENTS

1 SCOPE ................................................................................................................................... 2
2 CONFLICTS AND DEVIATIONS ........................................................................................... 5
3 REFERENCES ....................................................................................................................... 5
3.1 SAUDI ARAMCO REFERENCES ............................................................................................ 5
3.2 INDUSTRY CODES AND STANDARDS .................................................................................... 6
4 DEFINITIONS AND ABBREVIATIONS ................................................................................. 7
5 DESIGN REVIEW AND APPROVAL ................................................................................... 13
5.1 CONTRACTOR/DESIGNER Q UALIFICATIONS ........................................................................ 13
5.2 DESIGN REVIEW ............................................................................................................. 13
5.3 DESIGN BASIS SCOPING P APER (DBSP) ............................................................................. 14
5.4 P ROJECT P ROPOSAL ........................................................................................................ 14
5.5 DETAILED DESIGN .......................................................................................................... 15
6 DESIGN TECHNICAL REQUIREMENTS ............................................................................ 16
6.1 GENERAL ...................................................................................................................... 16
6.2 FIELD DAT A................................................................................................................... 20
6.3 DESIGN LIFE .................................................................................................................. 24
6.4 DESIGN CURRENT CRITERIA............................................................................................. 25
6.5 ANODES AND ANODE BEDS .............................................................................................. 29
6.6 CIRCUIT RESISTANCE ...................................................................................................... 33
6.7 DC P OWER SUPPLY......................................................................................................... 36
6.8 JUNCTION BOXES ........................................................................................................... 36
6.9 DC CABLES ................................................................................................................... 36
6.10 MONITORING ................................................................................................................. 37
6.11 BONDING ...................................................................................................................... 39
6.12 ELECT RICAL ISOLATION .................................................................................................. 39
7 INSTALLATION, RECORDS, COMMISSIONING AND INSPECTION ................................ 40
APPENDIX 1 – DESIGN QUALITY ASSURANCE CHECK LIST .............................................. 42
APPENDIX 2 – DRILL STEM AND TEST ANODE RESISTANCE MEASUREMENTS.............. 43
APPENDIX 3 – RECOMMENDED PROCEDURES ................................................................... 35
A3.1 MINIMIZING CASING CORROSION NEAR SURFACE ............................................................... 35
A3.2 EXTERNAL COATING ON WELL C ASINGS ........................................................................... 35
A3.3 GENERAL DECISION CHART FOR COATING “ONSHORE” WELL C ASINGS ................................. 36
A3.4 DETERMINATION OF WELL C ASING CURRENT REQUIREMENT ............................................... 37
A3.5 DRILLING DEEP ANODE HOLES ........................................................................................ 38
T ABLE_1A – CP CURRENT REQUIREMENT FOR GAS WELL CASINGS
T ABLE_1B – CP CURRENT REQUIREMENT FOR WATER INJECTION AND OIL WELL CASINGS
T ABLE_1C – CP CURRENT REQUIREMENT FOR WATER SUPPLY WELL CASINGS
T ABLE_2A – IMPRESSED CURRENT ANODE CONSUMPTION RATES AND NOMINAL DESIGN CURRENT DENSITIES
T ABLE_2B – GALVANIC ANODE CONSUMPTION RATES AND OPEN CIRCUIT P OTENTIAL
T ABLE_3 – IMPRESSED CURRENT HSCI ANODE DATA
T ABLE_4 – MINIMUM DISTANCE TO NEAREST CATHODICALLY P ROTECTED STRUCTURE
T ABLE_5 – RESISTANCE OF CASINGS TO REMOTE EARTH & BACK EMF OF CASINGS

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

1 Scope

1.1 This standard prescribes the minimum mandatory requirements governing the
design and installation of new cathodic protection (CP) systems protecting new
onshore metallic well casings. It may address existing wells if they are made
part of a group containing new wells.
Commentary Notes:
Replacements or in-kind replacements of existing, depleted or relocated anode
beds and/or CP systems do not need CSD approval except if they are part of a
new CP well installation. In such cases, existing wells do not need compliance
with the commissioning requirements specified in this standard, however
minimum monitoring current required shall be achieved as detailed in SAEP-333.

When a new well casing CP system is made part of a multi-well CP system

hosting existing well casings, then, only if required upgrade the existing CP
system to meet the monitoring current requirements of the existing wells.

Existing well casings without flowlines that lasted more than 30 years with no CP
and no external corrosion leaks do not need a new CP system unless mandated by
the proponent organization. The application of new CP in this case is not
recommended as it could have adverse effects if gases resulting from the
application of CP promoted the removal the corrosion products that prevented
casing leaks. Exception is when CP systems are installed within 500 meters from
unprotected structures.

The cathodic protection requirements for offshore well casings are beyond the
scope of this standard and are addressed in SAES-X-300. Onshore well casings
with anodes installed offshore (i.e., Pyramid anode) however are within the scope
of this standard.

Cathodic protection as addressed in this standard does not provide corrosion

protection for the inside surface of the well casing, tubing or liner.

Non-metallic (NM) flowline could act as an isolator hindering cathodic protection

continuity between the well casing and trunkline; hence, connect the CP negative
cable to the well casing rather than to the NM flowline. In such a case, only if
needed then provide a dedicated CP system for the trunkline while ensuring
adequate protection for all structures.

1.2 Cathodic protection systems for onshore well casings may be single dedicated,
shared (although not allowed by CSD) with negative bond, or multiple ICCP CP
systems.

Shared well casings are not allowed except for solar systems and multiple well
casings exceeding the limitations of multiple well casing CP system capacity
(more than 5 wells, requiring higher than 150 Amp TR, etc.) as detailed in
Section 6 below. In overlapping gas/oil fields, if a shared well CP system is
installed, then it will not be approved by CSD and it rather becomes the sole and
full responsibility of the proponent organization who approved/requested it,
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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

including the risk for well casing leak due to CP interference. Single well casing
CP system is not allowed where two wells are separated by less than 500 meters.
Drilling islands can have more than 5 wells connected to the same rectifier.

Galvanic anode are not normally used for well casing protection as the primary
permanent protection. Galvanic anode system could be used as a temporary
protection in areas where neither solar nor ICCP is practical if the soil resistivity
is promoting that option.

1.3 New, existing, carbon steel, stainless steel, coated, bare, onshore oil, gas,
unconventional gas, gas lift, observation, exploration, water injection, and water
supply metallic well casings with a predicted life expectancy greater than five
years shall be provided with cathodic protection within the time period specified
in Section 7 of this standard if:
a. The well casing is installed through a corrosive formation, or
b. The well casing is not installed through a corrosive formation, but has a
permanent buried metallic flow-line, in which case, sufficient CP shall be
provided to maintain the flow-line at an acceptable protection level in
accordance with SAES-X-400 without electrical isolation of the well
casing from the flow-line.
Commentary Notes:

Typically, well casings without flow-lines completed in or above the UER

formation do not require cathodic protection.

Where CP is not needed because the well casing is expected to last less than
5 years, if the proponent requires CP then it can be made out of scrap steel
anodes.

1.4 A metallic well casing that is not installed through a corrosive formation and
does not have a permanent flow-line does NOT require cathodic protection.
However, if a foreign impressed current anode bed is within 500 meters radius
of this type of well, electrical bonding shall be implemented to minimize the
probability of downhole interference.

1.5 For oil and water wells only, a metallic well casing that has not been coated with
Fusion Bonded Epoxy (FBE) and is installed within a metallic or non-metallic
cellar and backfilled shall be provided with galvanic magnesium anodes.
Install two pre-packaged 27.3 kg (60 lb) magnesium anodes inside the wellhead
cellar. Alternatively, clamp two 100-lb bare bracelet magnesium anodes within
the top one meter of the well head and connect the cable to the well casing at the
cellar zone to provide supplemental cathodic protection for the landing base
area. When upgrading an existing CP system, depleted magnesium anodes at
the cellar area shall also be restored. Measuring the potential and/or anode

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

current output at the cellar area is not needed to meet any protection criteria,
rather to ensure that the anodes are physically and electrically connected.
Commentary Note:

To provide further clarification for the above statement, supplemental galvanic

anodes for permanent protection of the landing base area are not required for
well casings that:
 do not have cellars, or
 are installed in cellars that are not backfilled, or
 are FBE coated on the top three joints through the cellar area, or
 gas well casings.

1.6 Temporary cathodic protection for well casings that will be protected with ICCP
is not required except where a temporary galvanic system is applicable as
detailed in paragraph 1.2 above.

1.7 This standard shall not be attached to, nor made a part of a purchase order.

2 Conflicts and Deviations

Requests to deviate from this standard shall be submitted electronically through the
SAP Waiver Process in accordance with SAEP-302, “Instructions for Obtaining a
Waiver.”

3 References

Referenced standards and specifications shall be the latest edition/revision unless stated
otherwise.

The Saudi Aramco Engineering Standards intranet website

(http://standards.aramco.com.sa:10009/) contains the latest revisions of all standards
and standard drawings.

3.1 Saudi Aramco References

Saudi Aramco Engineering Procedures

SAEP-302 Instructions for Obtaining a Waiver of a Mandatory
Saudi Aramco Engineering Requirement
SAEP-332 Cathodic Protection Commissioning
SAEP-333 Cathodic Protection Monitoring

Saudi Aramco Engineering Standards

SAES-B-062 Onshore Wellsite Safety
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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

SAES-P-104 Wiring Methods and Materials

SAES-X-300 Cathodic Protection of Marine Structures
SAES-X-400 Cathodic Protection of Buried Pipelines

Saudi Aramco Materials System Specifications

17-SAMSS-004 Conventional Rectifiers for Cathodic Protection
17-SAMSS-006 Galvanic Anodes for Cathodic Protection
17-SAMSS-007 Impressed Current Anodes for Cathodic Protection
17-SAMSS-008 Junction Boxes for Cathodic Protection
17-SAMSS-012 Modular Photovoltaic Power Supply for Cathodic
Protection
17-SAMSS-017 Impressed Current Cathodic Protection Cables
17-SAMSS-018 Remote Monitoring System (RMS) for Cathodic
Protection

Saudi Aramco Standard Drawings

AA-036385 Cathodic Protection - Deep Anode Bed
AA-036389 Galvanic Anode Details
AD-036785 Symbols for Cathodic Protection

Saudi Aramco Best Practice

SABP-X-003 Cathodic Protection Installation Requirements

Saudi Aramco General Instructions

GI-0002.710 Mechanical Completion and Performance
Acceptance of Facilities
GI-0428.001 Cathodic Protection Responsibilities

3.2 Industry Codes and Standards

National Fire Protection Association

NFPA 70 National Electrical Code (NEC)

National Electrical Manufacturers Association

NACE RP0186-2001 Application of Cathodic Protection for External

Surfaces of Steel Well Casings

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

4 Definitions and Abbreviations

This standard uses the following terminology:

AOC Aramco Overseas Company, The Hague
ASC Aramco Services Company, Houston
RSA Saudi Aramco Responsible Standardization Agency
JEDEC Joint Electronic Devices Engineering Council
SI International System of Units
SSPC Steel Structures Painting Council (USA)
UL Underwriter's Laboratories, Inc. (USA)
NEC National Electrical Code
FM Factory Mutual Research Corp.
CSA Canadian Standard Association

The following general list of definitions and abbreviations has been developed
specifically for application with Saudi Aramco cathodic protection standards
and specifications:

AA: The ANSI cooling class for a dry-type self-cooled transformer or reactor
that is cooled by the natural circulation of air. Syn.: AN (IEC), See definition
3.1 in IEEE C57.12.

Anode: An impressed current or a galvanic anode for cathodic protection

applications.

Anode Cable: A cable directly connected to an impressed current or galvanic

anode.

ANSI: American National Standards Institute

ANV: The ANSI cooling class for a dry-type non-ventilated self-cooled

transformer, which is so constructed as to provide no intentional circulation of
external air through the transformer, and that operates at zero gauge pressure.
Syn.: ANAN (IEC), See definition 3.15 in IEEE C57.12.

ASTM: American Society for Testing and Materials

AWS: American Welding Society

Armored Cable: Armored cable for cathodic protection is a single core

insulated cable manufactured with a double layer spiral wound insulated
galvanized steel sheath to provide mechanical protection, and typically used for
subsea applications.
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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
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Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

ASME: American Society of Mechanical Engineers (USA)

Bond Cable: A cable installed between two metallic structures to provide

electrical continuity between the structures for the purpose of cathodic protection.

Buyer: Saudi Aramco Purchasing Department Representative.

Buyer's Representative: The person or persons designated by the Purchasing

Department to monitor/enforce the contract. Normally, this is the on-site
inspector.

Calcined Petroleum Coke Breeze: A carbonaceous backfill used as a

conductive backfill media for impressed current anodes in soil.

Christmas Tree: The set of valves, spools and fittings connected to the top of a
well to direct and control the flow of formation fluids from the well.

CP: Cathodic Protection

Coated Casing: The term “coated casing” as used in this engineering standard
describes a well casing with an external non-conductive coating (typically Fusion
Bonded Epoxy or FBE). The coating must be applied to all sections of the casing
in contact with soil or formation, from surface to the bottom of the casing or to a
depth determined to facilitate external corrosion mitigation with cathodic
protection through the relevant down hole corrosive aquifers. Casings that have
been coated over the upper two or three joints of casing only are not “coated
casings”. Coating applied to well casings is not applied as a corrosion barrier.
It is applied to reduce the total amount of CP required or to extend the influence of
the applied CP.

CP Assessment Probe: A multi-electrode probe custom fabricated for Saudi

Aramco that is designed to facilitate representative measurements of instant off,
total polarization, current density, and resistivity.

CP Coupon: A cathodic protection coupon used to measure representative

potentials or current densities on a pipeline or other buried or immersed metallic
structure.

CP System Operating Circuit Resistance: The total resistance seen at the

output of a CP power supply or the total working resistance in a galvanic anode
system.

CP System Rated Circuit Resistance: The rated output voltage of a cathodic

protection power supply divided by the rated output current. For photovoltaic
power supplies, the rated output current is the design commissioning current.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Cross Country Pipeline: A pipeline between; two plant areas, another cross
country pipeline and a plant area, or between two cross country pipelines.

CSD: The Saudi Aramco Consulting Services Department.

Deep Anode Bed: Anode or anodes connected to a common CP power supply

and installed in a vertical hole with a depth exceeding 15 m (50 ft).

Design Agency: The organization responsible for the design of the pipeline and
associated CP system. The Design Agency may be the Design Contractor, the
Lump Sum Turn Key Contractor or an in house design organization of Saudi
Aramco.

Flowline: A pipeline connected to a well. A surface pipeline carrying oil, gas,

or water that connects the wellhead to a manifold .or to production facilities

Flare Line or Blow Down Line: A line for pumping out of unwanted gas or
hydrocarbon

Foundry (for anodes): An anode foundry is a facility that produces metal

castings from either ferrous or non-ferrous metals or alloys.

Galvanic Anodes: Anodes fabricated from materials such as aluminum,

magnesium or zinc that are connected directly to the buried structure to provide
cathodic protection current without the requirement for an external cathodic
protection power supply. Galvanic anodes are also referred to as sacrificial
anodes.

GOSP: Gas and Oil Separation Plant

Hazardous Areas: An area where fire or explosion hazards may exist due to
flammable gases or vapors, flammable liquids, combustible dust, or ignitable
fibers or filings (see NEC Article 500).

HDD: Horizontal Directional Drilling

ICCP: Impressed Current Cathodic Protection

Impressed Current Anodes: Anodes typically fabricated from High Silicon

Cast Iron (HSCI) or Mixed Metal Oxide (MMO) that are connected through a
DC power supply to the buried or immersed structure to provide cathodic
protection current.

Kill Line: A high-pressure pipe leading from an outlet on the BOP stack to the
high-pressure rig pumps

Lead Wire (for anodes): A cable directly connected to an anode.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
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Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Manufacturer: The Company that assembles the components for the finished
product and provides the finished product either through a Vendor or directly to
Saudi Aramco.

Megger: A four terminal meter designed to measure ground resistivity, or can

be connected to measure resistance in a format that excludes the resistance of
the test wires.

Multiple Well (Multi-well) Casing CP System: Two or more well casings

protected by one common CP rectifier system.

Mill (for anodes): An anode mill is a facility that produces anodes such as
MMO or Platinized Niobium (without lead wires) for cathodic protection
applications (or any other anode type that does not involve casting).

MSAER: Mandatory Saudi Aramco Engineering Requirements

NEC: National Electric Code

NEMA: National Electrical Manufacturers Association (USA)

Negative Cable: A cable that is electrically connected (directly or indirectly) to

the negative output terminal of a cathodic protection power supply or to a
galvanic anode. This includes bond cables to a cathodically protected structure.

Non-metallic Flowline: A flowline that is made out of non-metallic materials.

Non-incendive Equipment: Equipment having electrical/electronic circuitry

that is incapable, under normal operating conditions, of causing ignition of a
specified flammable gas-air, vapor-air, or dust-air mixture due to arcing or
thermal means. (See NEC Article 100).

Off-Plot: Off-plot refers to any area outside of the plot limits.

ONAN: The ANSI cooling class for a transformer or reactor having its core and
coils immersed in mineral oil or synthetic insulating liquid with a fire point less
than or equal to 300C, the cooling being effected by the natural circulation of air
over the cooling surface. (ONAN was previously termed OA). See definition
3.303 in IEEE C57.12.

On-Plot: On-plot refers to any area inside the plot limit.

Perimeter Fence: The fence which completely surrounds an area designated by

Saudi Aramco for a distinct function.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
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Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Photovoltaic Module: A number of solar cells wired and sealed into an

environmentally protected assembly.

Pipeline: The term “pipeline” is used generically to refer to any type of pipeline.

Plant Area: The area within the plot limits of a process or storage facility.

Plot Limit: The plot limit is the boundary around a plant or process facility.
The plot limit may be physical such as a fence, a wall, the edge of a road or pipe
rack, chains and posts or a boundary indicated on an approved plot plan.

Positive Cable: A cable that is electrically connected (directly or indirectly) to

the positive output terminal of an impressed current cathodic protection power
supply, including impressed current anode cables.

Process Pipeline: A pipeline typically associated with a plant process and

typically above ground within a plant facility.

Production Pipeline: A pipeline transporting oil, gas or water to or from a

well. These include flowlines, test lines, water injection lines, and trunklines.

Pyramid Anode: An offshore anode assembly custom manufactured for Saudi

Aramco that is fabricated with mixed metal oxide anode components and placed
on the sea bed. The pyramid anode derives its name from the pyramid shaped
concrete base.

Reference Electrode: An industry standardized electrode used as a common

reference potential for cathodic protection measurements. A copper/copper
sulfate (Cu/CuSO4) reference electrode is typically used for soil applications.
A silver/silver chloride (Ag/AgCl/0.6M Cl) reference electrode is typically used
for aqueous applications.

RSA: Responsible Standardization Agent - for CP material, this would usually

be the Supervisor of the CSD Cathodic Protection Team or the Saudi Aramco
CSD Cathodic Protection Subject Matter Expert.

Single Well Casing CP System: One well casing CP system protected by one
CP rectifier system.

Resistivity Meter (such as Megger Tester or equivalent): A meter designed

to measure ground resistivity, or can be connected to measure resistance in a
format that excludes the resistance of the test wires.

SAES: Saudi Aramco Engineering Standard

SAMSS: Saudi Aramco Materials System Specification

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
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Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Soil Transition Point: The surface location where a pipeline enters or exits the
soil, i.e., above grade to below grade transition, or below grade to above grade
transition.

Subject Matter Expert (SME): The SME is the assigned Consulting Services
Department cathodic protection specialist.

Shared Well Casing CP System: Two or more well casings protected by two or
more CP rectifier systems that are negatively bonded thru a Dedicated Bonding
Facility arrangement. Shared well casings are not allowed except for solar
systems.

Surface Anode Bed: Anode or anodes connected to a common CP power supply,

installed either vertically or horizontally at a depth of less than 15 m (50 ft).

Tension Spring Anode: An offshore anode assembly custom manufactured for

Saudi Aramco that is fabricated with mixed metal oxide anode components and
suspended on a wire rope/tension spring assembly beneath an offshore platform.

Test Line: A pipeline that is used for testing an individual well or group of wells.

Thermite Weld: An exothermic process for use in making electrical

connections between two pieces of copper or between copper and steel.

T/R: Transformer/Rectifier - A CP power supply that transforms and converts

AC to DC power, often referred to in the cathodic protection industry as a
rectifier.

Transmission Pipeline: A cross country pipeline transporting product between

GOSPs WIPs or other process facilities.

Trunkline: A pipeline designed to distribute or gather product from two or

more wells, typically connecting flowlines or injection lines to the associated
GOSP or WIP.

Utility Line: A pipeline that delivers a service product (typically water, gas, or
air).

Unconventional Deep Anode Bed: Anode bed drilled to typical depth of

120 meters thru dry drilling using air or foam with a geotextile liner to
120 meters and PVC water reservoirs on the top 60 meters.

Vendor: A company that receives a purchase order to supply the finished

product, material or equipment. The Vendor may also be the Manufacturer.

Venturi Spool: A gas metering spool recording apparatus at gas well sites.

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VpCI: Vapor Phase Corrosion Inhibitor

WIP: Water Injection Plant

Well Casing: Large-diameter pipe lowered into an open hole and cemented in
place.

Well Head: The system of spools, valves, and assorted adapters that provide
pressure control of a production well.

5 Design Review and Approval

5.1 Contractor/Designer Qualifications

5.1.1 Cathodic protection designs shall be completed by CSD approved local

design offices with a minimum of five years verifiable cathodic
protection design experience and a minimum industry qualification of
NACE CP Level 4 and BS degree. Indicate the NACE CP level,
certification number, name of designer and/or his signature/initial in the
design package.

5.1.2 Field measurements required for the design, survey, installation, walk-
through, pre-commissioning, commissioning, inspection, monitoring,
restoration, replacement, troubleshooting, field-investigation,
assessment, drill stem analysis, anode bed installation, etc. shall be
performed by an Engineer or Technician with a minimum industry
certification level of NACE CP Level 2. Indicate the NACE CP level,
certification number, name of designer and/or his signature/initial in the
design package.
Commentary Note:
As noted in GI-0428.001, PMT may request assistance from CSD for the
verification of the qualifications of the Design Contractor’s engineer responsible
for designing the CP systems and to approve new designers.

5.2 Design Review

5.2.1 DBSP and project proposal does not require conducting a site visit unless
that is mandatory to complete the package. The proposed construction
drawings and the related cathodic protection design information for
every design package shall at minimum be submitted to the CP
Proponent organization (as defined by GI-0428.001) and to Saudi
Aramco’s Consulting Services Department (CSD) or where applicable to
the CSD approved local design office Engineers for review and approval.
The most up to date list of approved design offices is posted on ShareK.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
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5.2.2 The Design Agency shall not issue drawings for construction until the
design has been reviewed and approved in writing by CSD or where
applicable by the CSD approved local design office Engineers and the
CP Proponent organization.

5.3 Design Basis Scoping Paper (DBSP)

Unless specifically requested by PMT, DBSP does not need to be reviewed or

approved by CSD per SAEP-303. The DBSP shall specifically state if cathodic
protection is required, or is not required, as dictated by SAES-X-700. No other
design considerations for cathodic protection are required for the DBSP.
DBSP may be reviewed by CSD approved local design offices.

5.4 Project Proposal

5.4.1 Unless specifically requested by PMT, project proposal does not need to
be reviewed or approved by CSD Project Proposal packages submitted to
CSD for review shall provide all design considerations that can be
developed without requiring the measurement of field data or a site visit.

5.4.2 The Project Proposal package shall include a specific statement in the
scope of work that clearly identifies any requirement to provide CP for
existing well casings, flow-lines or trunk-lines.

5.4.3 The Project Proposal shall provide clear direction on the general design
approach with respect to the following:
a. The CP systems shall be designed as:
● single well CP systems, or
● multi-well CP systems

b. The well casings are:

● coated casings, or
● bare casings

c. The CP power supply shall be:

● Photovoltaic, or
● Temporary galvanic, or
● AC powered
 air cooled, or
 oil cooled
 single phase, or
 three phase
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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
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5.4.4 The Project Proposal shall clearly state if remote monitoring equipment
will be included per 17-SAMSS-018 with the CP power supplies and if
so it shall provide the following general design information:
a. Will the CP power supply be provided with:
● signal transmitters, or
● a Remote Monitoring Unit (RMU)

b. What operating parameters are going to be monitored (must meet

minimum requirements)
c. What communication system will be used for the remote monitoring
system?
d. What software will be supplied for the CP Proponent? If the data is
not transmitted to the area Saudi Aramco PI data base, then the
software shall be provided through the Project.

5.4.5 The Project Proposal shall contain a professionally drafted Index “X” CP
layout drawing using the cathodic protection symbols shown on Standard
Drawing AD-036785 “Symbols for Cathodic Protection”, illustrating:
a. All existing and new well casings, buried/above grade metallic/non-
metallic, shorted/isolated flow-lines, test lines, pipelines, blowdown
lines, flare lines, bypass lines and trunk-lines associated with or
affected by the proposed CP system within the 1,000 meter radius of
the new well casing.
b. The proposed location of all CP equipment associated with the new
CP system with general details for:
● the proposed anodes and anode bed(s), location, type (surface,
deep conventional, deep unconventional), depth, number of
anodes, anode bed derating, anode to anode spacing, anode bed
to anode bed spacing, anode bed to buried structures spacing
● output ratings and condition for the existing/proposed CP power
supply and available spare capacity
● cable locations/route, lengths, number and sizes
● underground/above grade, metallic/non-metallic, existing/new
junction boxes, splice boxes and bond stations and their
condition

5.5 Detailed Design

5.5.1 Detailed Design packages shall provide all design considerations

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contained in the Project Proposal further developed based on the

collection of relevant field data including:
a. Measured soil resistivity for proposed anode beds that will be installed
shallower than 15 meters (surface) or deeper than 15 meters (deep)
b. Site information sufficient to develop a field verified site plan
(CP layout drawing) that clearly illustrates all proposed CP
equipment and all buried structures within 1,000 meter radius of the
new well casing(s) location.
c. Field verified operating data for existing CP equipment within
1,000 meter radius of the new well casing(s) location.
d. For detailed designs of multi-well CP systems in fields where the
casing resistances have not already been determined, site tests on
each relevant type of well casing to determine the respective
resistance-to–ground and structure back emf are required.

5.5.2 Detailed Design packages shall contain the original completed and signed
by CSD or where applicable by the CSD approved local design offices
“Well Casing Design Quality Assurance Check List” attached to the cover
letter or transmittal sheet for the design package (See Appendix 1).

5.5.3 Detailed Design packages shall contain all calculations and applicable
field data required to verify design compliance with the Saudi Aramco
Cathodic Protection Engineering Standards including an electrical
simulation drawing for all multi-well and shared-well CP systems.
Shared well casings are not allowed except as detailed in Section 6 below.

6 Design Technical Requirements

6.1 General

CSD approved CP designers are allowed to conduct the following activities in

lieu of CSD:
1) Develop the 90% detailed design CP package and IFC for single and
multiple well casings. While single shall go to construction without CSD
review or approval, multiple still requires CSD approval.
2) Analyze the drill stem and test anode resistances and provide anode
installation recommendations for single oil and water well casings.
3) Evaluate and approve the pre-commissioning report for single oil and water
well casings.

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6.1.1 Shared well casings are not allowed except for solar systems especially
bare and for multiple well casings exceeding the limitations of multiple
well casing CP system capacity (more than 5 wells and/or requiring
higher than 150 Amp TR, etc.). In overlapping gas/oil fields a shared
well casing is not allowed and thus it is a clear violation of this standard.
Requests for waivers will not be supported by CSD.

If a shared well CP system is installed (although not allowed by CSD),

then it will not be approved by CSD but rather becomes the sole and full
responsibility of the proponent organization who approved/requested that,
including the risk for well casing leak due to possible CP interference.

Shared well casings are only allowed in the following conditions

provided they are pre-approved by the proponent organization(s) in case
of overlapping gas/oil fields:
1) more than 5 wells within 500 meters from each other or from the
most recent well
2) current requirement is larger than 150 Amps
3) when the power source is solar especially for bare well casings
4) when the two CP systems are solar.

In overlapping fields where a share system is used which is not approved

by CSD, then if the most recently installed well is gas then the gas
proponent is responsible for the installation, commissioning, monitoring
and upgrade of both wells and to monitor the negative bond between the
two wells. Likewise, if oil is the most recent then the oil proponent is
the responsible organization. Otherwise, both proponents could agree on
who is responsible for what without CSD involvement. If shared
(although not allowed by CSD) well casings are used in overlapping site
with multiple oil and multiple gas wells, then consider to group the gas
together and oil together before sharing.

The proponent organization is responsible for connecting the CP system

after drilling and workover completed their drilling or wire line
operations. In overlapping fields, the responsible proponent as detailed
above will do that.

6.1.2 The design shall facilitate an integrated CP system for all associated
buried metallic structures, and shall comply with all spacing and access
restrictions detailed in SAES-B-062. The final design/IFC approval by
CSD can be thru an email, CRM or the like but does not necessarily need
to show the approval on every document/drawing. Rather, a list of
documents/drawings can be approved.
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6.1.3 CP power sources for an existing CP system shall not be utilized or be

made part of a multiple system to protect a new well casing within
500 meters radius without a prior approval from the CP Proponent
organization for the existing CP system. PMT is simultaneously
responsible to upgrade the existing CP system to meet the
commissioning requirements of the new well(s) and the monitoring
requirements of the existing well(s) and to meet the monitoring
potentials of all affected pipelines/flowlines within 1,000 meters from
the new well casing. At gas/oil overlapping fields, PMT is responsible to
obtain a prior approval from both CP Proponent organizations of the
overlapping fields about the plan to use single, multiple or shared CP
system, despite shared is not allowed.

During commissioning of a shared (although not allowed by CSD) well

site, it is required to meet the current requirement for each well whether
the negative cable bonding is connected or disconnected and with or
without a resistor.

6.1.3 Permanent stainless steel, carbon steel, bare, coated buried flare lines and
blow down lines on a well pad do not need a dedicated CP system, but
rather they shall be made permanently electrically continuous with the
well casing or the negative circuit of the well casing CP system to ensure
their adequate protection. If must be isolated, then protect them with
galvanic anode system. Bond across venturi spools with a metallic strap
at gas wells to ensure electrical continuity with the CP system and to
minimize the possibility of CP interference. Where non-metallic
pipelines are used (spools, flowlines, test lines and truck lines) bonding
across using a dedicated bond box is required. If isolation is a must, then
provide adequate CP for all metallic parts.

6.1.4 The use of a photovoltaic CP power supply shall be assessed by PMT

from an economic perspective for cathodic protection of new wells or
new fields considering the nearest 4.16 kV or 13.8 kV power line.
Commentary Notes:
The economic assessment shall include comparative costs for operations
and maintenance between the systems being considered. During the
DBSP review, the proponent organization can then verify stipulated
versus actual costs, and may consider other cost related factors like
future expansion and theft/vandalism issues.
For designs where photovoltaic power supplies are determined to be the
most cost effective alternative, consideration should be given by PMT to
place a request with the Saudi Aramco Drilling Dept. to have the well
casings externally coated to reduce the CP current requirement.

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Photovoltaic CP for a coated well casing typically has a notable cost

advantage over a bare well casing.

6.1.5 When demonstrated by the simulation program with calculated resistance

and current requirements, a dedicated CP power source shall be provided
for each well when the surface facilities for the two most distant wells
involved are separated by more than 500 meters. Otherwise, use
multiple design if the distance is within or less than 500 meters.
Commentary Notes:

In areas where theft and vandalism of a solar powered CP system and

cables is a concern to the CP Proponent, then to avoid theft of long runs
of buried cable, the cable shall be installed with approved below grade
and/or non-metallic junction boxes buried concrete anchors at each cable
end, and with minimal use of above grade cable identification markers.

Where applicable, custom made designs of galvanic anodes if viable may

be used instead of the solar power as a temporary CP power source for
single coated well casings if the soil conditions are promoting galvanic
anode efficiency, i.e., Midyan Field.

6.1.6 Well casings separated by less than 500 meters shall utilize a multiple
CP power source, provided the design protection criteria for each well as
stated in Tables 1A, 1B, and 1C of this standard are met without the use
of electrical resistors at the design stage. Electrical resistors maybe used
at the commissioning and/or operating stages provided that they are
intrinsically safe and are not installed in hazardous zones.
Exception:
If during commissioning of multi-well CP system, adequate current
distribution is not achieved, then resistors may be used. Resistors shall
be welded tap adjustable or fixed (non-adjustable) and shall be 0.15
ohms or less.

Commentary Note:

Coated well casings with normally above grade flowlines may use the
flowline for negative cable connection and hence do not require a
dedicated negative cable to each well but are still restricted by the
500 meter separation imposed on CP systems with multiple well casings
and shall meet all well casing and flowline protection requirements.

6.1.7 At sites where one CP power source is used to protect multiple well
casings, each uncoated well shall have a dedicated negative cable
connection. The negative cables shall be terminated in a negative
junction box located to optimize the current distribution between casings.

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6.1.8 CSD approved underground junction box may be used for an anode bed
junction box, bond box, splice box, or a negative cable junction box.
Commentary Note:

Underground junction boxes restrict the ability to measure current

distribution to the anodes or the structures and are only recommended for
use in areas where known repetitive cable theft and vandalism or other
operating conditions prohibit the use of above ground junction boxes.

6.2 Field Data

Field data and site verification of existing equipment that may affect or be
affected by the proposed CP system are required for the detailed design.

The following field investigation and data collection shall be completed and the
results included with all detailed design packages submitted for approval.

6.2.1 Existing Well Casings and Buried Pipelines

Verification and documentation (illustrate on the CP layout drawing) of

all buried pipelines and well casings, or other buried metallic structures
within 500 meters from the new well casing and the location of the
proposed CP power supply, anode bed, junction box, fence, rectifier,
pipeline, flow line or well casing.

6.2.2 Existing CP Systems

Measurement of all relevant cathodic protection currents in cables,

junction boxes, anode beds, grounding systems and flow-lines, plus all
relevant power supply voltages and currents, and all relevant structure
potentials. PMT is required to measure the well casing current at the
well head below the negative cable connection point especially for gas
wells using a clamp on ammeter. In addition, use the clamp to re-
confirm the well casing net current by measuring the current at the
flowline, kill line, test line, blowdown line, annulus line, trunk line, flare
line, grounding and all other connection points to the well head.
Measurement point on the wellhead P&ID and grounding drawings shall
be used to identify all underground grounding components, the type of
grounding, the way it is connected to the CP system and or site
structures, whether isolated or shorted in order to account for the
grounding current requirement at the design stage. Designs that neglect
grounding shall be rejected. Installations that do not meet all
commissioning requirements shall be re-sent to the design office for a re-
design and simulation if required. CSD can be consulted with thru a
TQ/CRM to resolve non-routine and complex issues, especially for
multiple well casings. All CP pre-commissioning requirements for new
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wells and flowlines shall be met and all monitoring requirements for
existing wells and flowlines shall also be met.

6.2.3 Soil Resistivity Measurement

Soil resistivity measurements are mandatory for all types of new and
existing anode beds; assumed or back calculated resistivities are not
allowed.

6.2.3.1 Shallow (Surface) Remote Anode Beds

a. Even after conducting surface resistivity measurements, the
preference is to use deep anode beds unless the site
conditions permit the use of surface anode beds, i.e., Subkha
soils. Install a watering system in very dry soil or use a
deep anode bed. Surface soil resistivity or soil conductivity
measurements shall be taken at 10 meter intervals. Soil
conductivities maybe measured using the four-pin, three-pin
or non-contact electromagnetic tools.
b. Measurements shall be taken for at least two soil layers
(typically 3 and 6 meter depths) down to the target
installation depth of the anode bed. Calculate the layer
resistivity to be used in the design.
c. Measurements shall be taken in parallel and perpendicular
orientations over the full length of the proposed shallow
anode bed location.
d. If the soil resistivities within a proposed shallow anode bed
vary by more than 100%, either additional anodes shall be
provided or, anodes of the same composition with a higher
current capacity can be placed in the low resistivity areas
so that no anode exceeds the maximum commission
current (Table 3).
e. The four-pin Wenner method may be used in areas with
nominal soil resistivities below 2,000 ohm-cm.
A non-contact electromagnetic soil resistivity/conductivity
instrument shall be used in areas where the nominal soil
resistivity exceeds 2,000 ohm-cm.
f. The proposed location for the shallow anode bed shall be
clearly marked with wooden or metal stakes at each end.
Show the location on the CP layout drawing.

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6.2.3.2 Deep Remote Anode Beds

a. Unless mandated and approved by the proponent, the max
deep anode bed depth is 120 meters, max no. of anodes per
hole is 20 anodes, anode to anode spacing shall be between
3 and ½ a meter, anode hole to anode hole spacing shall be
within 10 to 20 meters and use of slotted/non-slotted PVC
or metallic casing is not allowed, except for un-
conventional deep anode bed design.
b. Use un-conventional deep anode bed systems in areas
where the measured soil resistivity is extremely high
(typically higher than 50,000 ohm-cm) and/or the strata is
known to have cracks, voids, gaps or multiple loss
circulation zones. Soil resistivity or soil conductivity
measurements for both conventional and un-conventional
deep anode beds are mandatory for new/existing well
casing sites and/or new CP system upgrades.
c. Only use CSD recommended/approved drilling contractors
for drilling anode beds. Record drill stem and test anode
resistance measurements on the form contained in
Appendix 2 and submit for review and analysis to CSD or
to CSD approved local design offices as applicable.
Drill stem and test anode measurements are not required
for unconventional deep anode holes. The drill stem and
test anode measurements shall be taken in accordance with
the requirements detailed in Standard Drawing
AA-036385. CSD or CSD approved local design offices
as applicable shall determine the final acceptable borehole
depth, number of anodes, anode to anode spacing, number
of anode beds, separation between anode beds, size of the
rectifier, use of resistors and anode distribution.
Water level in the anode hole must be at the top of the
casing before taking each measurement.
d. Where a conventional deep anode bed was used but did not
meet the requirements due to high resistance, drill the new
anode beds as unconventional with a prior approval from
the proponent.
e. The proposed location for the deep anode bed shall be
clearly marked with a wooden or metal stake. Show the
location on the CP layout drawing.

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f. While drilling, PMT shall hold the job if any of the

following is encountered: high anode cable resistances,
loose connection to resistance meter or loss of fluid
circulation during drilling, coke breeze pouring, or anode
installation.
g. If commissioning could not be met due to facing high
anode bed resistance, then it could be due to missing
drilling procedures, wrong equipment or consumables,
extremely high resistivity soils, improper installation
practice, backfill settlement, air gaps, anode-cable contact
issues, dry backfill, loss of circulation fluid, cavities,
missing intermittent check/hold points. Possible solutions
include, to prepare a clear procedure for anode bed
installation with check and hold points, verify anode to
cable resistance before lowering the anodes, verify during
backfilling withhold points. Water volume, calcined
petroleum coke volume required shall be calculated in
advance and full calculated quantity must be filled and
recorded. Qualify and approve the drilling contractors to
meet to the procedure. Sample calcined petroleum coke to
be lab tested for its quality. Investigate foam drilling/steel
casings for loss of water areas.
h. When facing erratic drill stem and test anode data then that
is probably due to poor contacts, incorrect measurement
practices or dry measurements. Potential solutions could
be to use qualified persons for measurements, always
ensure proper electrolytic continuity, maintain wet
conditions, check water levels, and if necessary add water,
be able to check and re-measure if required before sending
the data for further processing, temporary power up the
anode bed following anode installation for current
distribution check.

6.2.3.3 Distributed Anode Beds

Distributed anodes are not used for well casing CP.

6.2.3.4 Galvanic Anode Locations

a. Galvanic anode are not normally used for well casing
protection as the primary permanent protection.
Galvanic anode system could be used as a temporary
protection in areas where neither solar nor ICCP is

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practical if the soil resistivity is promoting that option.

Soil resistivity measurements are required for temporary
galvanic anodes used for well casings and permanent CP
for flow lines or pipelines. Soil resistivity measurements
are not required for galvanic anodes used for supplemental
cathodic protection of well casings or associated pipelines.
b. Soil resistivity measurements taken by the design agent,
and ground water resistivity data supplied by the Saudi
Aramco Groundwater Protection organization, shall be
used for the design of galvanic anode systems used as a
temporary cathodic protection of well casings.
c. Drill stem and test anode resistance measurements to
validate the initial design parameters are mandatory for
deep galvanic anode systems used as a temporary source of
cathodic protection of well casings.

6.3 Design Life

6.3.1 Size ICCP anode beds to discharge the CP power source rated current
at the anode consumption rate detailed in Table 2, for a minimum of
20 years for HSCI anodes. MMO anodes shall be designed for 25 years.

 Total Weight of all Anodes (kgs.) 

 Anode Consumption Rate x CP Power Source Design Current Capacity   20 Years
 

6.3.2 Galvanic anode systems used for temporary or supplemental CP shall be

designed to provide a minimum life of 10 years for well casing CP.
Galvanic anode systems used for permanent CP shall be designed to
provide a minimum life of 20 years for flowline CP.
Exception:
Large magnesium anodes may be installed offshore to protect onshore
well casings and in such cases shall provide a minimum life of 10 years.

6.3.3 New Well Added to a CP System Less than 10 Years Old within 500
meters:

Use multiple CP systems for the addition of a new well within 500 meters
from an existing well(s), up to 5 wells and up to 150 Amp rectifier rating.
Otherwise PMT after securing the proponent approval may use a shared
CP system when in compliance with the exceptions for permitting the use
of shared CP systems as detailed in section 6 above. Upgrade the rectifier
to a higher level if needed and ensure that all new and existing well

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casings within 500 m and flowlines within 1,000 are adequately protected.
While new structures shall meet the commissioning requirement, existing
structures shall meet the monitoring requirements.

Where a new well is being added to a CP system commissioned within

the previous 10 years, an anode bed upgrade is NOT required if the
existing T/R and anode bed are capable of providing the required current
at an output voltage not greater than 90% (+/-10%) of the power supply
full rated voltage. If the required current for the existing wells and the
new well(s) cannot be achieved at 90% (+/-10%) or less of full rated
voltage, an anode bed upgrade shall be designed to comply on a prorated
basis (see 6.3.4). Upgrade the rectifier to a higher level if needed.

6.3.4 New Well Added to a CP System more than 10 Years Old within
500 meters

If requested by the proponent, evaluate replacing the rectifier, junction

box, bond box and splice box if more than 20 years old. Prorating is not
required for MMO anodes if the anode bed is less than 20 years old.
Where a new well is being added to a CP system that is more than
10 years old, the contribution of the existing anode bed to the overall
anode bed life and current capacity for the upgraded CP system shall be
calculated on a prorated basis using 10 years at full rated output as full
life. The existing anode bed shall be bonded to the new anode bed if
cost-optimal and in compliance with this standard. Use of the existing
anode beds should also be evaluated economically and practically as they
could be too far away and thus might be cost prohibiting or impractical
to utilize. Upgrade the rectifier to a higher level when needed. Use of
existing facilities requires the proponent’s approval.
Commentary Notes:
Example: 12 TA-4 anodes operating for 5 years at 23 amps would be
given a prorated remaining life contribution calculated as follows:

● 1 TA-4 anode has a capacity of 4.45 Amps x 10 year = 44.5 Amp-yr

● 12 TA-4 have a 10 year capacity of 44.5 x 12 = 534 Amp-yr
● 12 TA-4 at 23 Amps for 5 years have consumed 5 x 23 = 115 Amp-yr
● Prorated percent consumed = 115/534 x 100 = 21.5%
● Remaining prorated capacity = 78.5% x 12 anodes = 9.4 = 9 anodes

6.4 Design Current Criteria

6.4.1 Use externally coated casings for all new, onshore, oil, gas,
unconventional gas, gas lift, observation, exploration, water injection,

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and water supply metallic wells regardless of the well depth. This will
minimize the CP current requirement, allow use of multiple well casings,
reduce AC consumption and permit deployment of solar systems at
remote areas. If a bare well casing is used, then it shall be pre-approved
by the proponent and shall not be violating the general decision chart of
coating in Appendix A3.3 of this standard. The cathodic protection
system design shall provide the minimum design currents detailed in
Tables 1A, 1B, and 1C of this standard.
Commentary Note:

Galvanic cathodic protection systems used as the temporary cathodic

protection power source shall use the listed commissioning current for the
design minimum current output.

6.4.2 The CP requirements for well casings in fields specifically covered by

Tables 1A, 1B, or 1C have resulted from actual Corrosion Protection
Evaluation Tool (CPET) logging. Other fields were not logged and thus
shall be determined by future logging or extrapolation. Rectifier sizes in
Tables 1A, 1B, or 1C may be used as a guideline while alternative cost-
optimum sizes are also allowed. Upgrade the rectifier to a higher level
whenever needed.

6.4.3 The protection criteria for commissioning and monitoring are detailed in
Tables 1A, 1B, and 1C of this standard. Tolerance values of ±10% on
commissioning values during commissioning and on monitoring values
listed in Tables 1A, 1B, and 1C of this standard shall be implemented
where needed.
Exception:

A remote “instant off” potential of -850 mV or 100 mV of polarization

decay (instant off - steady state off) measured 150 meters away from the
well casing shall be accepted as a commissioning and monitoring
criterion for well casing CP systems that use galvanic anodes as the
temporary CP power source.

6.4.4 Multi-well (multiple) CP systems for new well(s) located within

500 meters from the nearest well shall be designed with one CP power
supply sized with a minimum rated output current equivalent to the sum
of the commissioning current requirement plus the estimated flow-line,
test line, kill line, flare line, blow down line and grounding system
current requirement plus a design surplus of 20%. Tolerance of ±10%
shall be considered when sizing the rectifier. Within the 500 meter
radius from a new well casing, the max rectifier size shall be 150 Amp,
max rectifier voltage shall be 100 V and max number of well casings per
rectifier shall be 5 wells. The 20% extra current is not required for

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single CP, unconventional gas, shared (not allowed by CSD), solar or

primary galvanic systems. Upgrade the rectifier to a higher level
whenever needed. Survey, bond thru a bond box and ensure adequate
protection for all buried pipelines and flowlines that belong to the new
well or to other facilities if they fall within 1,000 meters from the new
well. If the well casing is connected to a non-metallic flowline, then
bond all metallic pipelines, flowlines and trunklines that fall within the
1,000 meter radius of the new well to the well and together to ensure
electrical continuity. Use air-cooled rectifiers per 17-SAMSS-004 for
well casing sites.
Table 1A – CP Current Requirement for Gas Well Casings (6)
Gas Well Casings
Cathodic Protection Current Requirements – Single Well
Bare Casing Coated Casing
Com- Com- Operate/
Design Monitor Design
mission mission Monitor
Field Designation Minimum Current Optimum Minimum Current Optimum
Minimum Minimum
CP Power Included Casing CP Power Included Casing
Casing Casing
Supply for Operating Supply for Operating
Current Current
Rating Flow-line Current Rating Flow-line Current
(amps) (amps)
(amps) (amps) (amps) (amps) (amps) (amps)
Abu Jifan, Fazran, Khurais, Mazalij,
Midyan, Nuayyim, Shaybah
- T/R(2) 25 3 20 15-20 10 3 2 1.5-5
- Photovoltaic (1) 25 3(1) 20 15-20 7.5 3(1) 2 1.5-5
Ghazal, Jufayn, Kassab, Manjurah,
Sahba, Shaden, Tinat, Waqr,
(ZMLH), (MDRK), (AWTD), (WDYH)
- T/R(2) 50 3 40 35-40 10 3 2 1.5-5
- Photovoltaic (1) 45 3(1) 40 35-40 7.5 3(1) 2 1.5-5
Haradh, Hawiyah, Harmaliyah,
Midrikah, Nujayman, Shedgum,
Uthmaniyah, (ANDR), (DAMM),
(KRSN)
- T/R(2) 50 3 40 35-40 50 3 35 30-35
- Photovoltaic (1) 45 3(1) 40 35-40 45 3(1) 35 30-35

Table 1B – CP Current Requirement for Water Injection and Oil Well Casings (6)
Oil Production and Water Injection Well Casings
Cathodic Protection Current Requirements – Single Well
Bare Casing Coated Casing
Com- Com- Operate/
Design Monitor Design
mission mission Monitor
Field Designation Minimum Current Optimum Minimum Current Optimum
Minimum Minimum
CP Power Included Casing CP Power Included Casing
Casing Casing
Supply For Operating Supply For Operating
Current Current
Rating Flow-line Current Rating Flow-line Current
(amps) (amps)
(amps) (amps) (amps) (amps) (amps) (amps)
Uthmaniyah
- T/R(2) 50 3 35 30-35 15 3 7 5-7
- Photovoltaic (1) 45 0(1) 35 30-35 10 0(1) 7 5-7

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Oil Production and Water Injection Well Casings

Cathodic Protection Current Requirements – Single Well
Abqaiq, Abu Ali, Abu
Hadriyah, AinDar, Berri, Dammam,
Fadhili, Fazran, Hawiyah,
Khursaniyah, Manifa, Qatif,
Safaniyah, Shedgum
- T/R(2) 35 3 25 20-25 10 3 3 2-4
- Photovoltaic (1) 25 0(1) 25 20-25 7.5 0(1) 3 2-4
Ginah, Haradh, Hawtah, Harmaliyah,
Midyan, Nuayyim, Shaybah,
(ABMK), (Umjurf), (Hazmiyah), 25 3 15 12-15 10 3 2 1-3
(Nislah), (Burmah) 15 0(1) 15 12-15 7.5 0(1) 2 1-3
- T/R(2)
- Photovoltaic (1)
Abu Jifan, Khurais, Mazalij
- T/R(2) 10 3 4 2-5 5 3 1 0.5-5
- Photovoltaic (1) 7.5 0(1) 4 2-5 3 0(1) 1 0.5-5

Table 1C – CP Current Requirement for Water Supply Well Casings (3,4,5,6)

Water Supply Well Casings Deeper than the UER Formation

Cathodic Protection Current Requirements – Single Well
Bare Casing Coated Casing
Com- Com- Operate/M
Design Monitor Design
mission mission onitor
Field Designation Minimum Current Optimum Minimum Current Optimum
Minimum Minimum
CP Power Included Casing CP Power Included Casing
Casing Casing
Supply For Operating Supply For Operating
Current Current
Rating Flow-line Current Rating Flow-line Current
(amps) (amps)
(amps) (amps) (amps) (amps) (amps) (amps)
Abu Jifan, Khurais, Mazalij, (Fazran)
- T/R(2) 10 3 2 1-3 10 3 0.5 0.2-0.5
- Photovoltaic (1) 5 0(1) 2 1-3 5 0(1) 0.5 0.2-0.5
All Other Fields
- T/R(2) 10 3 6 5-7 10 3 1 0.5-1
- Photovoltaic (1) 7.5 0(1) 6 5-7 5 0(1) 1 0.5-1

General Notes:
 The following general notes are intended to address issues relating to tables 1A, 1B, and 1C.
 Fields indicated between two parentheses did not result from actual CPET logging, rather they are extrapolated based on
their geological location
 Bare well casings are not recommended unless mandated by the proponent provided bare casings are allowed per the
coating chart
 Consider ±10 % tolerances in the power source size in all tables 1A, 1B, and 1C current values
 Use 3 Amp of current for all flowlines at the design stage except for photovoltaic , rather use the values indicated in the tables
 Verify the actual commissioning and monitoring currents using a clamp-on ammeter around the well casing
 If needed, PMT shall coordinate with Drilling and Workover to conduct CPET logging for new fields while inviting CSD to witness
 If the flowline is not constructed yet, then the pre-commissioning will be rejected unless a temporary cable is used to
replicate the flowline
 A pre-commissioning report is approved if the well casing(s) is receiving the pre-commissioning current in the tables, rectifier
is not exceeding 90% (±10%) voltage, anodes are not exceeding the pre-commissioning current and the rectifier current is
compatible with the anodes while the system resistance does not exceed 90% and flowlines potential is meeting the criteria,
otherwise send back to the design for a re-design and re-modeling
 It has been field demonstrated that a few gas fields such as Utmn, Hwyh, Sdgm and Hrdh measured higher t han normal
current thru the F/L; therefore, a plan B shall be considered at the design stage to be prepared for a rectifier upgrade in case
needed to satisfy the commissioning requirements.

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Table Notes:
(1)
Solar flow line current shall be 3 Amps. CP current requirements for the flow-lines and trunk-lines of gas well casings
cathodically protected by temporary galvanic systems shall be determined on a site specific basis. If additional current is
necessary it shall be added to the current specified in tables 1A, 1B, and 1C. Include additional current for the grounding
system.
(2)
The current required for the flow-lines and trunk-lines for AC powered well casing CP systems is included in the “CP Power
Supply Rating (amps)” for T/Rs. If the flow-line or trunk-line is greater than 15 km long, additional current capacity
requirements shall be determined through calculations completed in accordance with SAES-X-400.
(3)
Table 1C applies to water supply wells that extend through the wet UER formation such as typical Wasia water supply wells.
Wells that do not extend below the UER (or other known corrosive formation), do not require CP. Wasia water wells drilled in
areas where the UER is dry, do not require cathodic protection unless mandated by the proponent
(4)
Regardless of the water well type, associated buried flow-lines must be cathodically protected in accordance with SAES-X-400.
(5)
Water wells without cathodic protection, and within 500 meters of an impressed current CP system anode bed, or
cathodically protected well casing must be bonded to the negative circuit of the CP system and supplied with sufficient CP
current to ensure down-hole interference does not create an external corrosion problem.
(6)
In this regard, the ∆V measured between the water well and the other protected structure within 500 meters should be less
than 200 mV measured with extended lead wires, well head to protected structure.

6.5 Anodes and Anode Beds

6.5.1 Impressed current and galvanic anodes shall be manufactured in

accordance with 17-SAMSS-007 and 17-SAMSS-006 respectively.
Exception:

Where site conditions necessitate the installation of anodes in soil

resistivities above 5,000 ohm-cm, alternative impressed current anode
types (not described by 17-SAMSS-007) may be used and require CSD
and proponent approval.

Commentary Note:

Nominal dimensional and weight data as specified in 17-SAMSS-007 for

HSCI anodes are contained in Table 3 of this standard for ease of
reference.

6.5.2 Anodes to be installed onshore deeper than 15 meters are classified as

“deep” anode beds and as such require the drilling depth to be pre-
approved in writing by the Saudi Aramco Groundwater Division,
Reservoir Characterization Department. PMT shall obtain this approval.

6.5.3 Deep anode beds shall be installed in accordance with the latest revision
of Saudi Aramco Standard Drawing AA-036385 “Cathodic Protection
Deep Anode Bed”.
Exception:

Where electrolyte resistivities or bore hole conditions are not suited to the
conventional installation detailed on AA-036385, alternative material and
installation configurations (unconventional deep anode bed) may be and
require CSD and proponent approval.

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6.5.4 For an anode bed discharging 25 amperes or more, a minimum distance of

150 meters shall be maintained between the nearest anode and the well
casing to establish electrical remoteness.
Exceptions:

Where electrolyte resistivities at the anode bed are below 1,000 ohm-cm,
the distance between the anode bed and the nearest well casing may be
less than 150 meters, but must be far enough from the nearest well
casing such that the calculated anodic gradient (∆V) at the well casing is
less than 1.0 volt using the resistivity determined at the anode bed.

For multiple well casing locations, the calculated difference in the anodic
gradient between any two well casings must also be less than 200 mV.

6.5.5 For an anode bed discharging less than 25 amperes, a minimum distance of
75 meters shall be maintained between the nearest anode and the well
casing.
Exceptions:

Where electrolyte resistivities at the anode bed are below 1,000 ohm-cm,
the distance between the anode bed and the nearest well casing may be
less than 75 meters, but must be far enough from the nearest well casing
such that the calculated anodic gradient (∆V) at the well casing is less
than 1.0 volt using the resistivity determined at the anode bed.

For multiple well casing locations, the calculated difference in the anodic
gradient between any two well casings must also be less than 200 mV.

6.5.6 Both mixed metal oxide (MMO) and high silicon cast iron (HSCI)
anodes can be used for anode beds. Procure MMO and HSCI anodes
from approved sources as specified by 17-SAMSS-007. Design
parameters for HSCI and MMO impressed current anodes shall be as
detailed in Table 2A and 17-SAMSS-007. Procure galvanic anodes from
approved sources as specified by 17-SAMSS-006. The design
parameters for galvanic anodes shall be as detailed in Table 2B, 17-
SAMSS-006, and Saudi Aramco Standard Drawing AA-036389.

Table 2A – Impressed Current Anode

Consumption Rates and Maximum Design Current Densities
Consumption Rate Anode Current Density
Anode Material
(kg/amp-y) (mA/cm²)
High Silicon Cast Iron 0.45 0.7
Require CSD
Mixed Metal Oxide Require CSD approval
approval
Commentary Note:

MMO anodes are more preferred than HSCI anodes due to their typical
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higher performance and longer life. The consumption rates detailed in

Table 2A include efficiency and the utilization factor for a HSCI tubular
anode. Shortening of the effective anode length due to an end cap on
the anode shall be neglected in the theoretical calculation of anode
current capacity. Polymeric anodes can be used for flowlines or
trunklines protection if conventional anodes have not been successful.

Table 2B – Galvanic Anode

Consumption Rates and Open Circuit Potential
Consumption Rate Open Circuit Potential
Anode Material
(kg/Amp-y) (mV vs Cu/CuSO4)
Aluminum 3.8 -1,100
Magnesium 10.95 -1,700
Zinc 11.8 -1,100

Commentary Note:
The consumption rates detailed in Table 2B include efficiency; include
0.85 utilization factor in the calculation.

6.5.7 The HSCI impressed current anodes most commonly used by Saudi
Aramco are listed in Table 3 below.

Table 3 – Impressed Current HSCI Anode Data

Maximum Maximum
Dimensions Weight
Type Design Current Commission
(nominal) (minimum)
Per Anode Current
TA-2 56 mm x 2133 mm 20.5 kg 2.63 amps 4.0 amps
TA-4 95 mm x 2133 mm 38.5 kg 4.45 amps 7.0 amps
TA-5A 121 mm x 2133 mm 79.0 kg 5.67 amps 10.0 amps

Commentary Note:

The maximum acceptable current during commissioning is based on

manufacturer's ratings and shall not be used for design. This number
shall only be used when determining commissioning acceptance.
Anodes with output less than 1 Amp during commissioning should not be
considered as acceptable. Tolerance values of +/-10% during
commissioning on the current is permitted in Table 3 above.

6.5.8 The ICCP current capacity of an ICCP anode bed shall be equal to or
greater than the design current for the associated CP power source and
shall be calculated as follows:
SA AB x Iφ  Iθ

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Where:
SA AB = The total surface area of all the anodes in the anode bed
I φ = Anode material current density per Table 2A
I θ = CP power source rated current output

6.5.9 Adjacent ICCP anode beds powered from separate CP power sources
shall be separated by a minimum distance of 50 meters. Adjacent ICCP
anode beds powered from the same CP power source shall be separated
by a minimum distance of 10 and max of 20 meters.

6.5.10 Impressed current anodes shall be designed to maintain the minimum

clearance detailed in Table 4 from any other cathodically protected
structure.

6.5.11 Adjacent deep anode beds can be treated as individual anode beds if the
separation between the anode beds meets or exceeds the minimum
distances detailed in Table 4. Use actual measured soil resistivities if
available.
Example:
Two 50 amp deep anode beds placed 75 meters apart in 2,500 ohm-
cm soil can be installed 75 meters away from a buried pipeline.

Table 4 – Minimum Distance to Nearest Cathodically Protected Structure

Minimum Distance in Meters
Anode Bed
as a Function of Average Soil Resistivity at Anode Bed
Rated Output
500 Ω-cm 1,000 Ω-cm
Current
(Amps) ρ < 500 Ω-cm ≤ρ≤ <ρ≤ ρ > 3,000 Ω-cm
1,000 Ω-cm 3,000 Ω-cm
0 – 35 20 meters 25 meters 50 meters 75 meters
36 – 50 30 meters 35 meters 75 meters 150 meters
51 – 100 65 meters 75 meters 150 meters 250 meters
101 – 150 100 meters 125 meters 225 meters 350 meters
Calculate the required distance to achieve an anodic gradient to
150+ remote earth of less than 1.8 volts using the soil resistivity measured
at the anode bed.

Exception:

The separation distance between an existing anode bed and a new buried
structure shall be acceptable if field measurements on the buried structure at the
nearest point to the anode bed demonstrate that the polarized (instant-off)

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potential is less than -1.20 volts (w.r.t. Cu/CuSO4). Tolerance values of ±10% on
all values are permitted in Table 4 above.

Commentary Notes:
1) The distances detailed in Table 4 are provided to limit the structure polarized
(instant-off) potential to less than -1.20 volts and to minimize the interference
effects on other independent cathodically protected structures. Polarized
potentials may be measured using a CP Assessment Probe or a CP potential
coupon, as detailed in SAEP-333 Appendix A-2.
2) For a new ICCP system, the “Anode Bed Output Current” value for Table 4 is the
rated current output of the new CP power supply.

6.6 Circuit Resistance

6.6.1 For a T/R, the CP system rated circuit resistance shall be defined as the
T/R rated voltage, divided by the T/R rated current. Rated voltages and
currents are as detailed on the manufacturer's data sheet/plate.
Example, 1 ohm is the rated resistance for a 50V/50A rectifier.

6.6.2 For a photovoltaic CP system, the rated circuit resistance shall be defined
as the photovoltaic system rated output voltage divided by the CP power
source minimum required rated current from Tables 1A, 1B, and 1C.

6.6.3 The CP system operating circuit resistance for an ICCP system shall be
defined as the total effective resistance seen by the output terminals of the
respective ICCP power supply, and for calculation purposes shall include:
a. Anode bed resistance-to-ground.
b. Positive cable resistance from CP power source to anodes.
c. Negative cable resistance from CP power source to structure(s).
d. Resistance of the casing to remote earth. This shall be as shown in
Table 5 unless site testing is completed to verify a more accurate
value.
e. Effective resistance caused by +0.8 volts anode bed back emf (for
HSCI/MMO in coke breeze) plus the structure back emf per Table 5
(example: + 0.8 volts anode bed back emf -1.2 volts casing back
emf = 2.0 volts total between the anode with coke breeze backfill
and a coated steel casing).

Remf = (+0.8V for anode bed back emf + structure back

emf per Table 5) / Irated
Irated = CP power supply “rated” current

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Exception:
A back emf of +1.0 volts (Cu/CuSO4) shall be used for MMO/HSCI
anodes in seawater, Subkha, or comparable high salinity wet
applications without coke breeze. This does not include the back
emf associated with the polarized potential of the structure.

Commentary Note:

When using Remf to calculate the maximum allowable anode bed

resistance to provide 70% of Rrated, the value of Remf must be
multiplied by 0.7 (70%).

Example: Ranodebed maximum = (0.7 x (Rrated - Remf)) - Rcables - Rstructure.

For a 50 V / 50 Amp rectifier, Ranodebed maximum = (0.7 x (50/50 –

(+0.8+1.2)/50)) - Rcables - Rstructure

Table 5 – Resistance of Casing-to-Remote Earth and Back EMF of Casings

Bare Coated Flow-line /
Production Production Bare Water Trunk-line Well Site
Characteristic Area or Water or Water Supply Well Network Grounding
Injection Injection Casing Network(2)
Casing Casing
Resistance of Qatif 0.015 0.07 0.05 0.055 0.20
Casing-to
Remote-Earth Khurais 0.10 0.30 0.15 0.20 0.70
(ohms) (1)
Structure Back
All Areas 1.17 1.2 1.15 1.2 1.0
EMF (volts) (1)
Note 1: The values contained in Table 5 are applicable to wells in the listed area. Areas with similar surface
formation and casing completion characteristics can be assumed to be similar for design purposes.
Otherwise, field testing is required in other areas to determine the appropriate design parameters for
back emf and resistance to ground of the relevant structures. Field testing and/or modeling to
determine the flowline/trunkline data in areas not listed above is required. For listed areas, field
verification and/or modeling is recommended.
Note 2: Consideration of the well site grounding network especially gas sites is required where an extensive
grounding network affects the current distribution at a well site such as would typically occur where
down hole pumps are used, or where the field has been constructed with metallic power poles with an
interconnected ground system.

6.6.4 ICCP system designs shall take into consideration the calculated
operating resistance and shall size the positive and negative cables and
voltage rating of the T/R such that the “calculated” operating output of
the T/R complies with all of the following:
a. At the design stage only, the target commissioning current shall be
achieved at a voltage between 40% and 60% of the T/R rated voltage
output. A pre-commissioning report is approved if the well casing(s)
is receiving the pre-commissioning current in the tables 1A, 1B, and
1C, rectifier is not exceeding 90% (±10%) voltage, anodes are not
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exceeding the pre-commissioning current and the rectifier current is

compatible with the anodes while the system resistance does not
exceed 90% and flowlines potential is meeting the criteria, otherwise
send back to the design for a re-design and re-modeling.
b. The normal operating output current shall be achieved with the
voltage adjustment set at more than 10% of the available (rated) T/R
voltage output.
c. This is a mandatory design requirement but is not a mandatory
requirement for commissioning acceptance.

6.6.5 The CP system “operating” circuit resistance measured during

commissioning of a new CP system shall not be greater than 90% of the CP
power supply “rated” circuit resistance unless all of the following are met:
a. If the CP system power supply is a tap adjustable T/R, it shall have
at least two fine tap setting increments remaining.
b. Each anode current, for the required minimum number of anodes is
at or below the maximum commissioning current rating (Table 3 of
SAES-X-700).
Exception:

The system can discharge the minimum current required for

commissioning listed in tables 1A, 1B, and 1C of SAES-X-700.

6.6.6 If during commissioning the flowline is measuring more than 5 Amps of

current, then investigate if this is a bare flow lines and/or sacrificial anode
drain, stray current drain, excessive grounding, large flowline network,
major unknown changes to previous mechanical/electrical arrangements.
Possible solutions include, to use only coated pipelines, identify changes
to grounding and piping, verify P&ID drawings, include grounding to be
part of CP design and simulation, isolate spools and consider resistance
bonding, increase CP system rating to higher current (i.e., 100 amps
instead of 50 amps) or conduct an investigation/study by PMT.

6.6.7 During commissioning, the compatibility of the anodes and rectifier

rating is not mandatory if the commissioning current can be achieved.

6.6.8 The drilling contractor is held accountable for the functioning of the
anode bed, must meet qualification requirements, either should have a
NACE CP 2 qualified technician onboard or subcontract this service,
prepare a clear procedure for anode bed installation with check and hold
points and to be qualified by CSD.

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6.7 DC Power Supply

6.7.1 Cathodic protection rectifiers and photovoltaic systems shall be

manufactured in accordance with 17-SAMSS-004 and 17-SAMSS-012
respectively.

6.7.2 The maximum allowed output rating for a DC power supply is 100 volts.

6.7.3 For hazardous areas (maximum Class 1 Zone 2), the design agency shall
select a cathodic protection DC power supply (and other CP system
equipment) that complies with the requirements of NEC Articles 500 to
504 for hazardous (classified) areas. CP equipment shall not be placed
in Class 1 Zone 1 areas.

6.7.4 Rectifiers with NEMA Class 3R enclosures shall NOT be used inside
hydrocarbon plant areas, within 30 meters of the plant perimeter fencing
(outside), or within 1 km of a coastline.

6.8 Junction Boxes

6.8.1 Junction boxes shall be manufactured in accordance with 17-SAMSS-008.

6.8.2 Anode junction boxes used with DC power supplies with a rated output
greater than 50 volts and a rated load resistance equal to or greater than
10 ohms shall utilize one of the following alternatives:
a. Shall use a non-metallic anode junction box, or
b. Shall have a protective clear plastic plate mounted in front of the
shunts, with holes drilled to facilitate measurement of the current
through each shunt.

6.8.3 Transformer/Rectifiers and junction boxes shall be permanently and

systematically labeled in line with the well site electrical devices and
equipment labeling system. Use T/R for transformer/rectifier and J/B for
junction box.

6.9 DC Cables

6.9.1 Cathodic protection DC cables shall be manufactured in accordance with

17-SAMSS-017.

6.9.2 DC cables connected to a CP power supply either directly or through a

junction box shall be shall be #6 (16 mm²) or larger. Cables larger than
16 mm2 shall be optimized in size to compliment the current capacity
and resistance requirements of the respective CP system.

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6.9.3 DC cables shall comply with the most recent edition of the National Fire
Protection Association NFPA 70, National Electric Code (NEC).

6.9.4 Unless otherwise specified by the cable manufacturer, the allowable

ampacity of High Molecular Weight Polyethylene (HMWPE) cables
manufactured in accordance with 17-SAMSS-017 shall be rated for
ampacity under the column for insulation rated for 90°C in the NFPA 70,
NEC Handbook. Correction shall be made to an operating conductor
temperature of 40°C.

6.10 Monitoring

6.10.1 The column titled “Monitor” in tables 1A, 1B, and 1C of this standard
shall be used as a guideline for adjusting the output of cathodic
protection systems to the optimum current output.

6.10.2 Remote monitoring

6.10.2.1 Where a remote monitoring system (RMS) is used, the design

details for the RMS shall be submitted to the CP SME in CSD
and the CP Proponent organization for review and approval.
Mandatory design details include:
a. A description of the existing CP RMS used by the
respective CP Proponent in the respective area (if
applicable). The description shall detail existing RMS
hardware, software, communication connectivity and
protocols.
b. Confirmation of proposed hardware and software
compatibility with the existing CP RMS (if applicable),
or written authorization by the CP SME in CSD and the
CP Proponent organization to use a non-compatible
RMS.
c. A data flowchart that illustrates the data path from the
CP power supply to the CP Proponent’s desktop
including connectivity details with software requirements
and communication protocols.

6.10.2.2 Remote monitoring systems for well casing cathodic

protection power supplies shall be designed and installed at
all new CP system installations where an RTU is located
within 500 meters of the CP power supply.

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a. The CP RMS shall at minimum use signal transmitters

for DC output voltage and current and a circuit breaker
status switch.
b. The data collected and stored by the CP remote
monitoring system shall be accessible by the CP
Proponent organization directly from their desktop
computer.

6.10.2.3 At locations where an existing useable RTU is not within

500 meters of the CP power supply, the need for a remote
monitoring system shall be determined by the Project Group
and the CP Proponent organization at the Project Proposal
stage.
Commentary Note:
Remote monitoring is strongly recommended for all Projects
that will be installing cathodic protection in a new field, or in
an existing field where monitoring of the new cathodic
protection systems in accordance with SAEP-333 will not be
practical with the existing cathodic protection technical staff.

6.10.2.4 Remote Monitoring Units (RMUs) for cathodic protection

power supplies shall comply with the requirements of
17-SAMSS-018.

6.10.2.5 Cables and field wiring used for the remote monitoring
systems shall comply with SAES-P-104.

6.10.2.6 Signal Transmitter Requirements for CP Remote Monitoring

Systems are as follows:
a. CP remote monitoring systems using signal transmitters
shall utilize two (preferably loop powered) 4-20 mA
signal transmitters to monitor the DC voltage and
current. A third channel (digital) shall be used to
monitor the CP power supply AC circuit breaker status.
b. The CP power supply shall be supplied with a circuit
breaker containing a factory built-in auxiliary status
switch to facilitate monitoring the CP power supply AC
circuit breaker status. This type of circuit breaker must
be clearly and specifically identified as a requirement on
the Material Purchase Order.
c. The wiring between the circuit breaker auxiliary switch,
signal transmitters, and the RTU must be sized such that
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the resistance is within the maximum load tolerance of

the signal transmitter (typically 600 ohms maximum).

6.11 Bonding

6.11.1 Well casings shall be electrically continuous with their associated piping.
Resistance bonding is not allowed during the design stage except to
balance the current during commissioning as detailed below.
Exception:

If adequate current distribution is not achieved during commissioning or

operation of a multi-well or shared cathodic protection system, the use of
electrical isolation devices accompanied by a bond station may be added if
approved by the CP Proponent organization. If resistors are necessary,
they shall be welded tap adjustable or fixed (non-adjustable) resistors and
shall be 0.15 ohms or less.

6.11.2 Electrically isolated flanged piping sections (spool pieces, i.e., Venturi
spool) installed in a flow-line or trunk-line for use with instrumentation
or other applications shall be bonded around using a metal bond strap
fabricated to facilitate a reliable bond around the isolated equipment and
ease of installation and removal, i.e., bolted.

Where a non-metallic pipeline or flowline is used, bond across to ensure

the electrical continuity to all metallic spools, test lines, trunk lines using
a dedicated bonding facility.

Bond all flowlines, test lines, trunk lines and pipelines thru a dedicated
bonding facility if they fall within 1,000 meters radius from a new well.
Bond all crossing pipelines that fall within the 1,000 meter radius.
For others farther away, bond at the closest pipelines crossing.
The proponent is responsible to monitor and restore the bonding stations
and to upgrade the CP system to ensure adequate protection on all
affected pipelines within the 1,000 meter radius. If existing bonding is
already present within the 1,000 meter radius then no additional
dedicated bonding is required.

6.12 Electrical Isolation

Electrical isolation shall not be installed between a well casing and the associated
flow-line.
Exceptions:

If adequate current distribution is not achieved during commissioning of a multi -

well cathodic protection system, the use of electrical isolation devices
accompanied by a bond station may be added if approved by the CSD CP SME

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for cathodic protection of onshore well casings and the Supervisor of the CP
Proponent organization. If resistors are necessary, they shall be welded tap
adjustable or fixed (non-adjustable) resistors and shall be 0.15 ohms or less.

Where an electrical isolating gasket is used to isolate between two flange faces,
it shall be installed at a location where the pipe is in a vertical orientation if
practical.

7 Installation, Records, Commissioning, and Inspection

7.1 Where cathodic protection is required as specified in this standard, it shall be

installed and pre-commissioned within one year after the drilling completion date
of the well in all areas. If a rig works on an existing well, then re-connection of
the CP systems after well completion or drilling and workover work shall be done
within 14 days from completing the work.
Exceptions:
1) Installation and pre-commissioning of cathodic protection may be delayed until the
flow-line has been installed at well casing locations where the well casing meets
all of the following criteria:
a. The well casing has not been externally coated or is a coated well drilled with
a total vertical depth greater than 8,000 feet.
b. AC power of distribution voltage is more than 5 km away.
c. Soil or shallow aquifer (within 100 meter depth) resistivities are greater than
500 ohm-cm and not conducive to achieving full CP with galvanic anodes.

2) Installation of cathodic protection may be delayed for up to 2 years in Uthmaniyah

and 3 years elsewhere for well casings where the associated flow-line or trunk-line
has been installed and meets all of the following criteria:
a. The trunk-line or flow-line has electrical continuity with the well casing through
mechanical connection, or electrical bonding.
b. The trunk-line is adequately cathodically protected.
c. The flow-line or trunk-line is adequately protected at a measurement point
1 km away from the well casing.
d. AC power of distribution voltage is more than 5 km away.

7.2 All pre-commissioning and commissioning shall be done according to

Tables 1A, 1B, and 1C of SAES-X-700, GI-0002.710, and SAEP-332.

7.3 Refer to Saudi Aramco Best Practice SABP-X-003 for detailed Installation,
Records, and Inspection requirements. SABP-X-003 shall be deemed a
mandatory document for this standard.

7.4 Refer to Saudi Aramco Engineering Procedure SAEP-332 for commissioning

requirements. The criteria listed in this standard for commissioning are directly
applicable to all pre-commissioning requirements.
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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Revision Summary
5 December 2012 Major revision.
 Revised protection criteria for photovoltaic systems for coated gas wells.
 Added an exception for multiple bare well casings spaced more than 2 km apart.
 Introduced statements to allow greater flexibility in the commissioning requirements.
 Added the requirement for NACE certification for design engineers and field technicians.
 Reworded the Scope and revised other relevant sections to allow the use of galvanic
anodes for CP of well casings.
 Added Mazalij and Midyan areas to the tables defining current requirements.
 Modified the statement in the current requirement tables that specified a general current
requirement for all fields not listed to stating that fields not listed require the criteria to be
determined by the CSD CP SME.
 Updated resistance parameters for coated and bare well casings for Khurais area.
 Revised and restated the time required before cathodic protection installation and
pre-commissioning is required.
 Modified anode bed upgrade requirements for a new well at existing multi-well locations.
 Changed the drill stem resistance measurement technique to a four wire method.
 Added observation wells into the scope of this standard.
 Standardized tables 1A, 1B, and 1C for flow-line current for photovoltaic CP systems
 Added a statement mandating non-metallic anode junction boxes for rectifiers with a
rated voltage above 50 volts and a load resistance of 10 ohms or more.
 Updated the Definitions.
 Added sections to clarify the requirements for the DBSP, Project Proposal, and Detailed
Design.
 Added the requirement for a simulation drawing for multi-well CP systems.
 Added sections to clarify the requirements for field testing and data collection for the
design.
 Added the requirement to contact the CSD SME for typical resistivity measurements for
deep anode holes where measurements haven’t been taken.
 Added an exception to allow the installation of deep anode beds in an arrangement
different than detailed in the Standard Drawings.
 Added an exception to allow anode beds to be closer to structures in low resistivity
environments.
7 November 2013 Minor revision.
 Update to include protection criteria for gas wells in Haradh Satellite field.
 Added clarification sketches to Appendix 2 (Drill Stem and Test Anode Analysis
Procedure).
 Updated Table 1A for gas wells.
 Updated commissioning and monitoring criteria to include an exception addressing well
casing CP systems with galvanic as the primary CP power source.
27 December 2017 Major revision.
 Required coated casing
 Did not allow shared well casing
 Max no of wells is 5, max current 150 Amp
 Revised flow line current
 Permitted exceeding the 90% voltage if the current is met
 Added ±10% tolerance on some tables
 Reduced the voltage tolerance from 30-70 to 20-60% during commissioning.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Appendix 1 – Design Quality Assurance Check List

BI- JO- Well Number
Item Done N/A Details for the Proposed Anode Bed shown on CP Layout Dwg.
1 The number and type of anodes (TA-2, TA-4, or TA-5)
2 Proposed installation configuration, i.e., shallow or deep, and
3 if deep then confirmation of acceptable depth from Groundwater Protection Division
4 Diameter, depth, and number of holes and,
5 if more than one hole, the spacing of the holes
6 The distance between the oil/gas/water well and the proposed anode bed
7 The location of any buried pipeline within 200 meters of the proposed anode bed.
If there are no buried pipelines (flow-line or other lines) within 200 meters of the
proposed anode bed, please state this in the notes section of the drawing
Item Done N/A Details for Existing CP equipment shown on CP Layout Dwg.
8 The age of existing anode bed and the number and type of anodes
9 The current distribution to existing wells for a multi-well system
10 Existing CP power supply operating output, or the measured operating resistance
to verify correct current balance between new and existing
Item Done N/A Details for Proposed DC Power Supply shown on CP Layout Dwg.
11 Rated DC volts and amps
12 Remote monitoring equipment details or a statement saying, “no remote monitoring”
13 The size and length of all DC cables for the proposed CP system
14 The CP junction boxes and their placement
Item Done N/A Calculations for Anode Beds (on CP Layout Dwg or on separate page)
15 Maximum allowable CP system resistance
16 Maximum allowable anode bed resistance
17 Calculated shallow anode bed resistance based on soil resistivity measurements
taken at site (not required for deep anode bed)
Item Done N/A Miscellaneous Requirements (on CP Layout Dwg or on separate page)
18 Simulation sketch showing satisfactory current distribution to each well if more
than one well casing is being protected by one rectifier
19 Verification statement that “ALL” buried ground cables on the site are insulated
(jacketed)
Please provide remarks below for any item from above that is applicable but not done:
Item ___
Item ___

Designer’s Name (Print) Signature and Date

Designer’s NACE Cert # PMT Engineer Name (Print)

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Appendix 2 – Drill Stem and Test Anode Resistance Measurements

Well
______________________ Submitted By: ____________ Date: ________
Designation:

New CP System Data Place an X in the box if no new CP power supply or anodes
CP Power Supply Anode Hole(s) Anodes
Target Maximum Max. What Type
DC Volts DC Amps Quantity Other
Hole____ of ____ Resistance Resistance Depth(m) TA-2, 4 or 5

Existing CP System Data Place an X in the box if no existing CP power supply or anodes
Existing CP Power Supply
Existing Anode Hole(s) Existing Anodes
Rated Volts____ Rated Amps____
Operating Operating Manufacture Shallow Number Measured Resistance What Type Installation
Quantity
DC Volts DC Amps Date or Deep? of Holes to Well Casing (Note 2) TA-2, 4, or 5 Year

Measurement Equipment Data:

Resistance
Resistance Measurements Length (meters) Size (AWG or mm2)
(ohms)
(Note1) 25 Two wire #14AWG
Resistance of the Test Wires and Connection
200 (or more) Two wire #14AWG
Resistance of the Cable on the Test Anode (Note3) 100 16 mm2

Drill Stem and Test Anode Resistance Measurement Data (Report directly as read from meter)
Drill Stem(Note2) Test Anode (Note2)
Depth (m) Soil Type Remarks
Resistance (ohms) Resistance (ohms)
Water level in the anode hole must be at the top of the casing before taking each measurement!!!!!!!
6
9
12
15
18
21
24
27
30
33
36
39
42
45
48
51
54
57
60
63
66
69
72
75
Continued on next page.
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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Appendix 2 – Drill Stem and Test Anode Resistance Measurements (continued)

Drill Stem Test Anode
Depth (m) Soil Type Remarks
Resistance (ohms) Resistance (ohms)
78
81
84
87
90
93
96
99
102
105
108
111
114
117
120

Notes:
1. Procedure to measure the resistance of the “test wires and connections”:
 Unspool 25 meters of #14 AWG wire. Connect one end to terminal C1 on the Megger.
 Unspool another 25 meters of #14 AWG wire. Connect one end to terminal P1 on the Meter.
 Tightly twist the open ends of the two 25 meter wires together and clamp to a bolt or flange on the well
head (use vice grips or a “C” clamp – do not use alligator clip, spring clip or spring clamp).
 Unspool 200 meters (typical) of #14 AWG. Connect one end to terminal C2 on the Meter.
 Unspool another 200 meters (typical) of #14 AWG wire. Connect one end to terminal P2 on the Meter.
 Tightly twist the open ends of the two 200 meter wires together and clamp to the same bolt or flange on
the wellhead (use vice grips or a “C” clamp – do not use alligator clip, spring type clamp).
 Measure the resistance with the Meter. Record the resistance measured as shown on the meter. It will
typically be less than 0.01 ohms.
Production
Well Casing
Meter Connections

C1
P1
P2
C2

Do NOT place a direct

short between any of
the terminals!

2. Procedure to measure the resistance of the drill stem, or test anode, or anode bed:
 Unspool 25 meters of #14 AWG wire. Connect one end to terminal C1 on the Meter.
 Unspool another 25 meters of #14 AWG wire. Connect one end to terminal P1 on the Meter.
 For Drill Stem , twist the open ends of the two 25 meter wires together and clamp to the frame of the drill
truck (use vice grips or a “C” clamp – do not use alligator clip, spring clip or spring clamp).
 For test anode resistance measurement, clamp these two wires to the end of the test anode cable
instead of the drill truck.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

 For anode bed resistance measurement, clamp these two wires to the bus bar in the anode junction
box instead of the drill truck.
 Unspool 200 meters (typical) of #14 AWG wire. Connect one end to terminal C2 on the Meter.
 Unspool another 200 meters (typical) of #14 AWG wire. Connect one end to terminal P2 on the Meter.
 Twist the open ends of the two 200 meter wires together and clamp to a bolt or flange on the wellhead
(use vice grips or a “C” clamp – do not use alligator clip, spring clip or spring clamp)
 Record the resistance shown on the Meter.
Wellhead

Meter Connections

C1
P1
P2
C2
Do NOT place a direct short Well Casing
between any of the terminals!

3. Procedure to measure the resistance of the test anode cable:

 Unspool 25 meters of #14 AWG wire. Connect one end to terminal C1 on the Meter.
 Unspool 25 meters of #14 AWG wire. Connect one end to terminal P1 on the Meter.
 Twist the open ends of the two 25 meter wires together and clamp to one end of the anode (use vice grips
or a “C” clamp – do not use alligator clip, spring clip or spring clamp).
 Uncoil the test anode cable and loop the cable end back towards the meter in a single loop.
 Short terminals C2 and P2 of the Meter (use a short strand of wire to connect terminal C2 to terminal P2).
 Connect the cable from the test anode to the P2 terminal.

Meter Connections

C1
P1
P2
C2
Test Anode
Place a direct short
between Terminals C2
and P2 for this test only

Test Anode Cable

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

Appendix 3 – Recommended Procedures

A3.1 Minimizing Casing Corrosion near Surface

To minimize corrosion of the well casings inside cellars, in the landing base area, or
near surface, the following procedures should be implemented:

 Use an external FBE coating on the top two joints of all casings that extend to
surface.
 Drilling operations should ensure that all cement is removed from the base of
the cellar after each cement job to prevent the formation of a cement floor.
 Fill all annuli near surface with cement to displace air or water in the annuli.
 Seal the annular space between casings in the landing base area by seal welding
the casings at surface (including the surface casing or conductor casing) to stop
the ingress of air into the annular space between the casings.
 Seal (weld closed) any windows cut in the casings for top jobs, etc.

A3.2 External Coating on Well Casings

A3.2.1 The application of FBE to the external side of well casings may be used to
effectively reduce the current requirement to approximately 10% of the
cathodic protection current required for a similar non-coated casing.
A3.2.2 The application of FBE to the external side of well casings may be used to
effectively increase the depth of influence of a cathodic protection system.
Nominal attenuation characteristics for 16 mils (400 microns) of FBE
coating applied to the external side of the well casing to a depth of 6,000 to
8,000 feet will typically extend adequate cathodic protection by 3,000 to
4,000 feet further into the bare casing section.
A3.2.3 The application of FBE to the external side of well casing tubulars should
be restricted to a maximum thickness of 25 mils (625 microns). Additional
thickness creates problems due to the tight closing tolerances of the casing
installation equipment.
A3.2.4 Casing with collar can be FBE coated effectively without removal of the
collar if a preheat is completed on the collar before running the casing
section through the assembly line induction oven, and by manually back
spraying into the casing/collar crevice immediately before the collar enters
the spray chamber.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

A3.3 General Decision Chart for Coating “Onshore” Well Casings

Does the casing pass through the UER, Wasia,

Yes
or Jilh, at a MD greater than 5000’?

No

Does the casing pass through the Arab-C

formation in an area where the Arab-C is over Yes
pressured, i.e., Uthmaniyah?

No

Will the well location be provided with No

permanent AC power?

Yes

Will there be more than two wells on this drill Yes

pad/island?

No

Is primary CP achieved on the well by current

through the flow-line/trunk-line system, Yes
i.e., Khurais?

No

Apply FBE (max 25 mils) to the external side of Apply FBE (max 25 mils) to the casing surfaces
all casings, including the conductor, to at least in contact with the formation from surface to at
50’ below surface. No other coating on the least 500’ below the deepest corrosive
casing is recommended. formation to a maximum TVD of 8000’.

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

A3.4 Determination of Well Casing Current Requirement

A3.4.1 Well casing corrosion in the Arabian Gulf area is typically caused by long
line corrosion currents that are generated between two or more down-hole
formations. The shallowest of the formations with an anodic response are
typically more than 1000 feet deep and the area experiencing corrosion
typically doesn’t affect more than one or two lengths of casing.
A3.4.2 Corrosion can typically be attributed to poor quality cement in the
casing/bore-hole annulus often amplified by the presence of flowing
formation conditions or acid gases. Downhole corrosion cannot be
detected by surface measurement techniques such as “E Log I”, and cannot
be reliably modeled using only formation resistivities and casing data.
A3.4.3 The most reliable method (and arguably the only reliable method) of
determining the amount of CP current required to mitigate long line
corrosion in a downhole formation is to run a CP evaluation log.
(Note: CP evaluation logs are not effective for localized corrosion cells).
Cathodic protection evaluation logs have been run by Saudi Aramco in the
following fields; Abqaiq, Abu Ali, Ain Dar, Haradh, Hawiyah, Hawtah,
Marjan, Nuayyim, Qatif, Safaniyah, Shaybah, Shedgum, and Uthmaniyah.
A3.4.4 Before CP is turned on; a cathodic protection evaluation log can be run to
identify corrosive formations. However, due to the time delay for
polarization of the casing, a log that is run to identify corrosion currents
cannot reliably be immediately followed by a second log to determine the
quantity of CP current required to overcome the corrosion currents.
A3.4.5 A CP evaluation log can be run to determine the amount of CP required to
mitigate long line corrosion currents but a nominal amount of cathodic
protection should be applied two weeks or more prior to running the log.

 When running the log, the actual amount of current going to the casing
must be measured with a current clamp placed around the casing.
It would be misleading to use the output current of the CP power supply
because the flow-line and surface facilities associated with the rig will
also take some of the current.

 The flow-line for the well will typically be physically disconnected

during the logging procedures and must be bonded to the well head for
the logging to accurately simulate actual operating conditions.
This bond should be in place immediately after the flow-line is
disconnected from the well head. If the bond is not installed,
interference currents from nearby CP systems that would not occur
when the flow-line is connected may occur when the flow-line is

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Document Responsibility: Cathodic Protection Standards Committee SAES-X-700
Issue Date: 27 December 2017
Next Planned Update: 27 December 2020 Cathodic Protection of Onshore Well Casings

disconnected and in such cases would distort conclusions drawn from

the logging information.

 For best results, the CP evaluation logging tool should be run at a

maximum pull rate of 1,500 feet per hour and station stops should be
made every 5 feet in areas where higher resolution is desirable, and
every 10 feet in areas where lower resolution is acceptable.

 For best results, the cathodic protection logging tool should be left
stationary at the lowest depth of the log for a period of 15 to
30 minutes before beginning the calibration part of the log. This delay
is required to facilitate temperature stabilization of the tool.

 The cathodic protection evaluation logging tool should be provided

with new blades at the beginning of each casing investigation, and
should be provided with dielectric or electrically isolated stand-offs /
centralizers. These are of particular importance for logging non-
vertical casing segments.

 The use of the surface reference electrode (often termed “fish” by the
logging vendor) is not required.

A3.5 Drilling Deep Anode Holes

A3.5.1 Drilling Equipment
Drill deep anode holes with rotary type drilling equipment that
circulates the cuttings to surface by water (or water/mud mixture)
through the hollow center of the drill pipe. Do NOT use equipment
that drills a dry hole, or does not circulate drilling fluid to remove
cuttings unless the formation characteristics dictate the use of a dry
drilling technique such as is required in Khurais.
A3.5.2 Use of Casing
 Case the top 3 to 6 meters as required to maintain hole integrity
through poorly consolidated surface soils.
 Do not install anodes inside any cased section of the hole.
 Use cement plugs to seal lost circulation areas, or bentonite if
necessary. Do not use casing in areas where anodes will be placed (the
casing will later corrode and the backfill dissipate into the formation
leaving the anodes without complete backfill).
 If a water table is reached, casing can be installed to the top of the
water table, but all anodes should be installed below the top of the
water table to facilitate equalized current loading on the anodes.
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