ISO 15589-1:2003
(Main)Petroleum and natural gas industries — Cathodic protection of pipeline transportation systems — Part 1: On-land pipelines
Petroleum and natural gas industries — Cathodic protection of pipeline transportation systems — Part 1: On-land pipelines
ISO 15589-1:2003 specifies requirements and gives recommendations for the pre-installation surveys, design, materials, equipment, fabrication, installation, commissioning, operation, inspection and maintenance of cathodic protection systems for on-land pipelines, as defined in ISO 13623, for the petroleum and natural gas industries. ISO 15589-1:2003 is applicable to buried carbon steel and stainless steel pipelines on land. It can also apply to landfalls of offshore pipeline sections protected by onshore-based cathodic protection installations. ISO 15589-1:2003 is also applicable to retrofits, modifications and repairs made to existing pipeline systems. NOTE Special conditions sometimes exist where cathodic protection is ineffective or only partially effective. Such conditions can include elevated temperatures, disbonded coatings, thermal insulating coatings, shielding, bacterial attack and unusual contaminants in the electrolyte.
Industries du pétrole et du gaz naturel — Protection cathodique des systèmes de transport par conduites — Partie 1: Conduites terrestres
General Information
Relations
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 15589-1
First edition
2003-11-15
Petroleum and natural gas industries —
Cathodic protection of pipeline
transportation systems —
Part 1:
On-land pipelines
Industries du pétrole et du gaz naturel — Protection cathodique des
systèmes de transport par conduites —
Partie 1: Conduites terrestres
Reference number
ISO 15589-1:2003(E)
©
ISO 2003
---------------------- Page: 1 ----------------------
ISO 15589-1:2003(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.
© ISO 2003
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2003 — All rights reserved
---------------------- Page: 2 ----------------------
ISO 15589-1:2003(E)
Contents Page
Foreword. v
Introduction . vi
1 Scope. 1
2 Normative references . 1
3 Terms and definitions. 2
4 Symbols and abbreviations . 4
5 Design requirements . 4
5.1 General. 4
5.2 Design information . 4
5.3 Criteria for CP. 5
5.4 Predesign investigations. 6
5.5 Electrical isolation . 7
5.6 Electrical earthing . 8
5.7 Electrical continuity. 8
5.8 Current requirements . 8
5.9 Type of CP system and selection of sites . 9
6 Impressed-current systems . 10
6.1 Power supply. 10
6.2 Groundbeds. 11
6.3 Current output control and distribution . 13
7 Galvanic-anode systems. 14
7.1 General. 14
7.2 Zinc anodes . 14
7.3 Magnesium anodes. 15
7.4 Anode backfill. 16
7.5 Cables and cable connections . 16
8 Monitoring facilities . 16
8.1 General. 16
8.2 Monitoring stations (test posts) . 16
8.3 Bonding to other pipelines. 17
8.4 Test facilities at cased crossings. 17
8.5 Test facilities at isolating joints. 17
8.6 Drain-point test facilities . 17
8.7 Miscellaneous monitoring facilities . 17
9 Special facilities . 17
9.1 Temporary protection. 17
9.2 Protective casings . 17
9.3 Parallel power lines or a.c. traction systems .18
9.4 Lightning protection . 18
9.5 Surge arrestors . 18
9.6 CP cables and cable connections . 18
9.7 Monitoring stations and distribution boxes. 19
10 Commissioning . 20
10.1 General. 20
10.2 Equipment tests . 20
10.3 System tests . 21
© ISO 2003 — All rights reserved iii
---------------------- Page: 3 ----------------------
ISO 15589-1:2003(E)
11 Inspection and monitoring .21
11.1 General .21
11.2 Frequencies of inspection.21
11.3 Monitoring plan.22
11.4 Monitoring equipment.23
11.5 Specialized surveys .23
12 Maintenance and repair .23
13 Documentation .24
13.1 Design documentation.24
13.2 Commissioning documentation.25
13.3 Inspection and monitoring documentation .25
13.4 Operating and maintenance documentation .25
13.5 Maintenance records .26
Annex A (normative) CP measurements .27
Annex B (normative) Electrical interference.31
Annex C (informative) Fault detection of impressed-current systems during operation.35
Annex D (informative) Description of specialized surveys.37
Bibliography.40
iv © ISO 2003 — All rights reserved
---------------------- Page: 4 ----------------------
ISO 15589-1:2003(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 15589-1 was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore structures
for petroleum, petrochemical and natural gas industries, Subcommittee SC 2, Pipeline transportation systems.
ISO 15589 consists of the following parts, under the general title Petroleum and natural gas industries —
Cathodic protection of pipeline transportation systems:
Part 1: On-land pipelines
Part 2: Offshore pipelines
© ISO 2003 — All rights reserved v
---------------------- Page: 5 ----------------------
ISO 15589-1:2003(E)
Introduction
Pipeline cathodic protection is achieved by the supply of sufficient direct current to the external pipe surface,
so that the steel-to-electrolyte potential is lowered to values at which external corrosion is reduced to an
insignificant rate.
Cathodic protection is normally used in combination with a suitable protective coating system to protect the
external surfaces of steel pipelines from corrosion.
External corrosion control in general is covered by ISO 13623.
Users of this part of ISO 15589 should be aware that further or differing requirements may be needed for
individual applications. This part of ISO 15589 is not intended to inhibit alternative equipment or engineering
solutions to be used for the individual application. This may be particularly applicable where there is innovative
or developing technology. Where an alternative is offered, any variations from this part of ISO 15589 should
be identified.
vi © ISO 2003 — All rights reserved
---------------------- Page: 6 ----------------------
INTERNATIONAL STANDARD ISO 15589-1:2003(E)
Petroleum and natural gas industries — Cathodic protection
of pipeline transportation systems —
Part 1:
On-land pipelines
1 Scope
This part of ISO 15589 specifies requirements and gives recommendations for the pre-installation surveys,
design, materials, equipment, fabrication, installation, commissioning, operation, inspection and maintenance
of cathodic protection systems for on-land pipelines, as defined in ISO 13623, for the petroleum and natural
gas industries.
This part of ISO 15589 is applicable to buried carbon steel and stainless steel pipelines on land. It can also
apply to landfalls of offshore pipeline sections protected by onshore-based cathodic protection installations.
This part of ISO 15589 is also applicable to retrofits, modifications and repairs made to existing pipeline
systems.
NOTE Special conditions sometimes exist where cathodic protection is ineffective or only partially effective. Such
conditions can include elevated temperatures, disbonded coatings, thermal-insulating coatings, shielding, bacterial attack
and unusual contaminants in the electrolyte.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 8044, Corrosion of metals and alloys — Basic terms and definitions
ISO 13623, Petroleum and natural gas industries — Pipeline transportation systems
ISO 13847, Petroleum and natural gas industries — Pipeline transportation systems — Welding of pipelines
1)
ASTM G 97 , Standard test method for laboratory evaluation of magnesium sacrificial anode test specimens
for underground applications
1) American Society for Testing and Materials, 100 Barr Harbour Drive, West Conshohocken, PA 19428-2959, USA
© ISO 2003 — All rights reserved 1
---------------------- Page: 7 ----------------------
ISO 15589-1:2003(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8044 and the following apply.
3.1
anode backfill
material with a low resistivity, which may be moisture-retaining, immediately surrounding a buried anode, for
the purpose of decreasing the effective resistance between the anode and the electrolyte and to prevent
anode polarization
3.2
bond
metal conductor, usually copper, connecting two points on the same or on different structures, usually with the
intention of providing electrical continuity between the points
3.3
cathodic protection system
system consisting of a d.c. current source and an anode in order to provide protective current to a metallic
structure
3.4
coupon
representative metal sample of known surface area used to quantify the extent of corrosion or the
effectiveness of applied cathodic protection
3.5
d.c. decoupling device
protective device that conducts electricity when predetermined threshold voltage levels are exceeded
EXAMPLE Polarization cells, spark gaps and diode assemblies.
3.6
drain point
location of the negative cable connection to the protected structure through which the protective current
returns to its source
3.7
galvanic anode
electrode that provides current for cathodic protection by means of galvanic action
3.8
groundbed
system of buried or immersed galvanic or impressed-current anodes
3.9
impressed-current anode
electrode that provides current for cathodic protection by means of impressed current
3.10
impressed-current station
station containing the equipment which provides cathodic protection by means of impressed current
3.11
impressed-current system
system which provides cathodic protection by means of impressed current
2 © ISO 2003 — All rights reserved
---------------------- Page: 8 ----------------------
ISO 15589-1:2003(E)
3.12
instant-on potential
structure-to-electrolyte potential measured immediately after turning on all sources of applied cathodic
protection current
3.13
intensive measurement technique
technique which simultaneously measures pipe-to-electrolyte potentials and associated perpendicular
potential gradients
NOTE The intensive measurement technique identifies coating defects and enables calculation of IR-free potentials
at the defects.
3.14
IR drop
voltage, due to any current, developed between two points in the metallic path or in the lateral gradient in an
electrolyte such as the soil, measured between a reference electrode and the metal of the pipe, in accordance
with Ohm’s Law
3.15
IR-free potential
polarized potential
structure-to-electrolyte potential measured without the voltage error caused by the IR drop from the protection
current or any other current
3.16
isolating joint
electrically-insulating component inserted between two lengths of pipe to prevent electrical continuity between
them
EXAMPLE Monobloc isolating joint, isolating flange, isolating coupling.
3.17
monitoring station
test post
station where measuring and test facilities for the buried pipeline are located
3.18
on-potential
structure-to-soil potential measured while the cathodic protection system is continuously operating
3.19
off potential
instant-off potential
structure-to-electrolyte potential measured immediately after interruption off all sources of applied cathodic
protection current
NOTE This potential is normally measured immediately after the cathodic protection system is switched off and the
applied electrical current stops flowing to the bare steel surface, but before polarization has decreased.
3.20
protection potential
structure-to-electrolyte potential for which the metal corrosion rate is insignificant
3.21
reference electrode
electrode whose open circuit potential is constant under similar conditions of measurement, used to measure
the structure-to-electrolyte potential
© ISO 2003 — All rights reserved 3
---------------------- Page: 9 ----------------------
ISO 15589-1:2003(E)
3.22
remote earth
that part of the electrolyte in which no measurable voltages, caused by current flow, occur between any two
points
NOTE This condition generally prevails outside the zone of influence of an earth electrode, an earthing system, an
impressed-current groundbed or a protected structure.
3.23
stray current
current in the path other than the protective current under consideration
4 Symbols and abbreviations
a.c. alternating current
CP cathodic protection
CSE copper−copper sulfate (saturated) reference electrode
d.c. direct current
SCC stress corrosion cracking
SCE calomel reference electrode
5 Design requirements
5.1 General
For new construction projects, the design of the CP system shall be part of the total pipeline design and
corrosion management. The details of the pipeline isolation (e.g. location of isolating joints) and the protective
coating system shall be included.
Design, fabrication, installation, operation and maintenance of CP systems shall be carried out by experienced
and qualified personnel.
5.2 Design information
The following technical information shall be collected and considered when designing a CP system:
detailed information on the pipeline to be protected, e.g. length, diameter, wall thickness, type and grade
of material, protective coating, operating temperature profile, design pressure;
products to be transported;
the required design life of the CP system;
relevant drawings of the pipeline route, showing existing CP systems, existing foreign structures/pipelines
etc.;
environmental operating conditions for the CP equipment;
topographical details and soil conditions, including soil resistivity;
4 © ISO 2003 — All rights reserved
---------------------- Page: 10 ----------------------
ISO 15589-1:2003(E)
climatic conditions, e.g. frozen soil;
the possibility of telluric current activity;
location, route and rating of high-voltage overhead or buried power lines;
valves and regulating station locations;
water, railway and road crossings;
casing pipes that will remain after construction;
types of pipeline bedding material;
types and locations of isolating joints;
characteristics of neighbouring a.c. and d.c. traction systems (e.g. electrical substations and their
operating voltages and polarities) and other interference-current sources;
types and locations of earthing systems;
availability of power supply.
The following information should be considered in the design of the pipeline CP system:
soil pH, and the presence of bacteria which can cause corrosion;
types and locations of neighbouring telemetry systems which can be used for remote monitoring.
5.3 Criteria for CP
5.3.1 General
The metal-to-electrolyte potential at which the corrosion rate is less than 0,01 mm per year is the protection
potential, E . This corrosion rate is sufficiently low so that corrosion will be within acceptable limits for the
p
design life. The criterion for CP is therefore
E u E
p
The protection potential of a metal depends on the corrosive environment (electrolyte) and on the type of
metal used.
The protection potential criterion applies at the metal/electrolyte interface, i.e. a potential which is free from the
IR drop in the corrosive environment (IR-free potential/polarized potential).
Some metals can be subject to hydrogen embrittlement at very negative potentials, and coating damage can
also increase at very negative potentials. For such metals, the potential shall not be more negative than a
limiting critical potential E . In such cases, the criterion for CP is
l
E u E u E
l p
5.3.2 Protection criteria
5.3.2.1 The CP system shall be capable of polarizing all parts of the buried pipeline to potentials more
negative than −850 mV referred to CSE, and to maintain such potentials throughout the design life of the
pipeline. These potentials are those which exist at the metal-to-environment interface, i.e. the polarized
potentials.
© ISO 2003 — All rights reserved 5
---------------------- Page: 11 ----------------------
ISO 15589-1:2003(E)
To prevent damage to the coating, the limiting critical potential should not be more negative than −1 200 mV
referred to CSE, to avoid the detrimental effects of hydrogen production and/or a high pH at the metal surface.
For high strength steels (specified minimum yield strength greater than 550 MPa) and corrosion-resistant
alloys such as martensitic and duplex stainless steels, the limiting critical potential shall be determined with
respect to the detrimental effects in the material due to hydrogen formation at the metal surface. Stainless
steels and other corrosion-resistant alloys generally need protection potentials more positive than −850 mV
referred to CSE; however, for most practical applications this value can be used.
For pipelines operating in anaerobic soils and where there are known, or suspected, significant quantities of
sulfate-reducing bacteria (SRB) and/or other bacteria having detrimental effects on pipeline steels, potentials
more negative than −950 mV referred to CSE should be used to control external corrosion.
For pipelines operating in soils with very high resistivity, a protection potential more positive than −850 mV
referred to CSE may be considered, e.g. as follows:
−750 mV for 100 < ρ < 1 000;
−650 mV for ρ W 1 000
where ρ is the soil resistivity, expressed in ohm metres.
As an alternative to the protection potentials given above, a minimum of 100 mV of cathodic polarization
between the pipeline surface and a reference electrode contacting the electrolyte may be used. The formation
or decay of polarization shall be measured in accordance with A.2.3.
5.3.2.2 The application of the 100 mV polarization criterion shall be avoided at higher operating
temperatures, in SRB-containing soils, or with interference currents, equalizing currents and telluric currents.
The conditions should be characterized prior to using this criterion. Furthermore, the criteria shall not be used
in case of pipelines connected to or consisting of mixed metal components
5.3.2.3 Under certain conditions, pipelines suffer from high-pH SCC in the potential range −650 mV to
−750 mV, and this shall be considered when using protective potentials more positive than −850 mV.
5.3.2.4 Care should be exercised in the use of all protection criteria where the pipeline is electrically
continuous with components manufactured from metals more noble than carbon steel, such as copper
earthing systems.
5.3.2.5 For pipelines operating at temperatures above 40 °C, the above values may not provide adequate
protection potential. In these cases, alternative criteria shall be verified and applied.
5.3.3 Measurements of protection potentials
Measurement techniques shall be in accordance with Annex A.
Other practical reference electrodes to CSE may be used for the various criteria provided that their properties
are reliable and documented.
If a.c. interference is present on a pipeline, a.c. corrosion can occur even though the protection potential is
achieved (see Annex B).
5.4 Predesign investigations
A site survey shall be carried out before preparing the pipeline CP design. Information obtained during
previous site surveys relevant to the proposed pipeline route may be used provided that the date and source
of such surveys are documented. If the area to be surveyed is affected by seasonal changes, these shall be
taken into account and the most severe conditions with respect to the soil conditions shall be used for the
design.
6 © ISO 2003 — All rights reserved
---------------------- Page: 12 ----------------------
ISO 15589-1:2003(E)
The survey report shall contain the design information specified in 5.2.
Representative soil resistivity values should be obtained at pipeline depth along the route of the pipeline, and
shall be obtained at various depths at prospective locations for anode groundbeds. The number of
measurements should be based on local soil conditions. If there are changes in soil characteristics, more
measurements shall be taken.
If corrosive conditions are anticipated due to bacterial activity, appropriate action shall be taken which might
include chemical and bacterial analyses of the soil. This requirement shall be extended to the imported soil
used for pipeline trench construction.
Possible sources of detrimental d.c. and a.c. interference currents shall be investigated, and the design shall
include measures to mitigate the effect of such currents. Annex B shall apply with respect to the detection and
control of interference currents.
Locations where high-voltage a.c. transmission lines or a.c.-powered train systems cross, or run parallel to,
the pipeline shall be identified.
5.5 Electrical isolation
Isolating joints should be installed above ground whenever possible at both extremities of a pipeline, and
should also be considered at the following locations:
at connections to branch lines;
between pipel
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.