SIST EN ISO 13174:2013
(Main)Cathodic protection of harbour installations (ISO 13174:2012)
Cathodic protection of harbour installations (ISO 13174:2012)
This International Standard defines the means to be used to ensure that cathodic protection is efficiently applied to the immersed and driven/buried metallic external surfaces of steel port, harbour, coastal and flood defence installations and appurtenances in seawater and saline mud to provide protection from corrosion.
Kathodischer Korrosionsschutz für Hafenbauten (ISO 13174:2012)
1.1 Allgemeines
Die vorliegende Europäische Norm definiert die Möglichkeiten, die zu verwenden sind, um sicherzustellen, dass genügend kathodischer Korrosionsschutz an die unter Wasser befindlichen und eingerammten/bodenbedeckten metallenen Außenflächen von stählernen Hafen-, Küsten- und Hochwasserschutzanlagen und Zubehör in Meerwasser und salzhaltigem Schlick angewendet wird, um Schutz vor Korrosion zu bieten.
1.2 Konstruktionen
Diese Europäische Norm definiert den kathodischen Korrosionsschutz von ortsfesten und schwimmenden Hafenkonstruktionen. Hierzu zählen Piers, Anleger, Duckdalben (Festmachen und Anlegen), Wände aus Spundbohlen oder Rohrpfählen, Pontons, Bojen, Schwimmdocks, Schleusentore und Wehrverschlüsse.
Sie definiert den kathodischen Korrosionsschutz von den eingetauchten Flächen von Zubehör wie beispielsweise Ketten, die an den Konstruktionen befestigt sind, jedoch nicht elektrisch von der Konstruktion isoliert sind.
Sie definiert den kathodischen Korrosionsschutz der erdbedeckten Flächen, typischerweise in Erdböden oder mit Sand aufgeschüttete Flächen hinter Pfahlwänden oder innerhalb von gefüllten Senkkästen, die erheblich von Korrosion befallen werden könnten. Spezielle kathodische Korrosionsschutzentwurfs- und Betriebsanforderungen an Anlagen in Böden sind in EN 12954 definiert. Typischerweise wird diese Europäische Norm mit Bezug auf kathodische Korrosionsschutzsysteme verwendet, bei denen sich die Anoden in Wasser oder salzhaltigem Schlick befinden; gewöhnlich wird EN 12954 angewendet, wenn sich die Anoden an Land befinden.
Sie deckt nicht den kathodischen Korrosionsschutz von ortsfesten oder schwimmenden Offshore-Anlagen (einschließlich Offshore-Ladebojen), untermeerischen Rohrleitungen oder Schiffen ab.
Protection cathodique des installations portuaires (ISO 13174:2012)
L'ISO 13174:2012 spécifie les moyens à mettre en ?uvre pour garantir qu'une protection cathodique est appliquée efficacement aux surfaces métalliques externes immergées et battues ou enfouies des installations portuaires, côtières et anti-crue en acier et de leurs parties annexes exposées à l'eau de mer et aux boues marines afin d'assurer leur protection contre la corrosion.
L'ISO 13174:2012 spécifie la protection cathodique des ouvrages portuaires fixes et flottants. Ces ouvrages comprennent les appontements, les jetées, les ducs d'Albe (d'amarrage et d'accostage), les palplanches ou les pieux tubulaires, les pontons, les bouées, les docks flottants, les portes et vannes d'écluses. Elle spécifie également la protection cathodique des surfaces submergées des parties annexes, par exemple les chaînes connectées à l'ouvrage, lorsqu'elles ne sont pas isolées électriquement de l'ouvrage.
L'ISO 13174:2012 doit être utilisée pour les systèmes de protection cathodique dont les anodes se trouvent dans l'eau ou dans les boues marines. Pour les zones enfouies, typiquement dans les remblais en sable ou en terre derrière des rideaux de palplanches battus ou à l'intérieur de caissons de soutènement, qui peuvent être affectées de manière significative par la corrosion, les exigences spécifiques relatives à l'étude et au fonctionnement de la protection cathodique sont définies dans l'EN 12954, les anodes étant exposées aux sols.
L'ISO 13174:2012 n'est pas applicable à la protection cathodique des ouvrages offshore fixes ou flottants (y compris les bouées de chargement offshore), des canalisations sous-marines ou des navires.
L'ISO 13174:2012 n'inclut pas la protection interne des surfaces des composants tels que les ballasts, les surfaces intérieures des compartiments ennoyés des ouvrages flottants, les portes et vannes d'écluses, ou encore les surfaces intérieures des pieux tubulaires en acier.
L'ISO 13174:2012 traite de la protection cathodique des ouvrages réalisés principalement à partir d'aciers au carbone et au carbone-manganèse nus ou revêtus.
Certaines parties de l'ouvrage pouvant être réalisées en matériaux métalliques autres que les aciers au carbone, il convient de concevoir le système de protection cathodique de manière à assurer une parfaite maîtrise de tout couplage galvanique et à réduire au minimum les risques dus à la fragilisation hydrogène ou à la fissuration induite par l'hydrogène (voir l'ISO 12473).
L'ISO 13174:2012 n'est pas applicable aux ouvrages en béton armé (voir l'EN 12696).
L'ISO 13174:2012 est applicable à l'ensemble des zones submergées en eau de mer, en eau saumâtre et dans les boues marines, ainsi qu'aux zones enfouies associées qui font normalement partie des ouvrages, fixes ou flottants, des installations portuaires, côtières et anti-crue.
En ce qui concerne les surfaces qui sont de façon intermittente immergées et exposées à l'atmosphère, la protection cathodique n'est efficace que lorsque le temps d'immersion est suffisamment long pour permettre la polarisation de l'acier. La protection cathodique est généralement efficace pour toutes les surfaces situées sous le niveau moyen des marées.
Pour les ouvrages tels que les rideaux de palplanches et de pieux tubulaires en acier qui sont battus dans le fond marin ou pour ceux qui sont partiellement enfouis ou sont recouverts de vase, l'ISO 13174:2012 est également applicable aux surfaces enfouies, battues et envasées qui vont bénéficier d'une protection cathodique en même
Katodna zaščita za pristaniške napeljave (ISO 13174:2012)
Ta mednarodni standard določa učinkovit način nanosa katodne protikorozijske zaščite na potopljene in poganjane/podzemne zunanje površine jeklenih luških, pristaniških, obalnih in protipoplavnih napeljav in opreme v morski vodi ter slanem blatu.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 13174:2013
01-maj-2013
1DGRPHãþD
SIST EN 13174:2003
.DWRGQD]DãþLWD]DSULVWDQLãNHQDSHOMDYH ,62
Cathodic protection of harbour installations (ISO 13174:2012)
Kathodischer Korrosionsschutz für Hafenbauten (ISO 13174:2012)
Protection cathodique des installations portuaires (ISO 13174:2012)
Ta slovenski standard je istoveten z: EN ISO 13174:2012
ICS:
25.220.40 Kovinske prevleke Metallic coatings
47.020.01 Splošni standardi v zvezi z General standards related to
ladjedelništvom in shipbuilding and marine
konstrukcijami na morju structures
SIST EN ISO 13174:2013 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 13174:2013
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SIST EN ISO 13174:2013
EUROPEAN STANDARD
EN ISO 13174
NORME EUROPÉENNE
EUROPÄISCHE NORM
December 2012
ICS 77.060; 47.020.99 Supersedes EN 13174:2001
English Version
Cathodic protection of harbour installations (ISO 13174:2012)
Protection cathodique des installations portuaires (ISO Kathodischer Korrosionsschutz für Hafenbauten (ISO
13174:2012) 13174:2012)
This European Standard was approved by CEN on 18 December 2012.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United
Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 13174:2012: E
worldwide for CEN national Members.
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SIST EN ISO 13174:2013
EN ISO 13174:2012 (E)
Contents Page
Foreword . 3
2
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SIST EN ISO 13174:2013
EN ISO 13174:2012 (E)
Foreword
This document (EN ISO 13174:2012) has been prepared by Technical Committee CEN/TC 219 “Cathodic
protection", the secretariat of which is held by BSI, in collaboration with Technical Committee ISO/TC 156
"Corrosion of metals and alloys".
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by June 2013, and conflicting national standards shall be withdrawn at
the latest by June 2013.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 13174:2001.
According to the CEN/CENELEC Internal Regulations, the national standards organisations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
3
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SIST EN ISO 13174:2013
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SIST EN ISO 13174:2013
INTERNATIONAL ISO
STANDARD 13174
First edition
2012-12-15
Cathodic protection of harbour
installations
Protection cathodique des installations portuaires
Reference number
ISO 13174:2012(E)
©
ISO 2012
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SIST EN ISO 13174:2013
ISO 13174:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
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 2012 – All rights reserved
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SIST EN ISO 13174:2013
ISO 13174:2012(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
1.1 General . 1
1.2 Structures . 1
1.3 Materials . 1
1.4 Environment . 1
1.5 Safety and environment protection . 2
2 Normative references . 2
3 Terms and definitions . 2
4 Competence of personnel . 4
5 Design basis . 5
5.1 Objectives. 5
5.2 Cathodic protection criteria . 5
5.3 Design parameters . 6
5.4 Electrical current demand . 7
5.5 Cathodic protection systems . 9
5.6 Electrical continuity .11
5.7 Interactions .11
6 Impressed current systems .12
6.1 Objectives.12
6.2 Design considerations.12
6.3 Equipment considerations .13
7 Galvanic anode systems .16
7.1 Objectives.16
7.2 Design .16
7.3 Materials .16
7.4 Location of anodes .17
7.5 Installation .17
8 Commissioning, operation and maintenance .18
8.1 Objectives.18
8.2 Commissioning: galvanic systems .18
8.3 Commissioning: Impressed current systems .18
8.4 Operation and maintenance .19
9 Documentation .20
9.1 Objectives.20
9.2 Impressed current system .20
9.3 Galvanic anodes system .21
Annex A (informative) Guidance for current requirements for cathodic protection of
harbour installations .22
Annex B (informative) Anode resistance, current and life determination .24
Annex C (informative) Typical electrochemical characteristics of impressed current anodes .29
Annex D (informative) Guidance related to the design process .30
Bibliography .32
© ISO 2012 – All rights reserved iii
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SIST EN ISO 13174:2013
ISO 13174:2012(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 13174 was prepared by the European Committee for Standardization (CEN) Technical Committee
CEN/TC 219, Cathodic protection, in collaboration with Technical Committee ISO/TC 156, Corrosion of
metals and alloys, in accordance with the Agreement on technical cooperation between ISO and CEN
(Vienna Agreement).
ISO 13174 cancels and replaces EN 13174:2001, which has been technically revised.
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SIST EN ISO 13174:2013
ISO 13174:2012(E)
Introduction
Cathodic protection is applied, sometimes in conjunction with protective coatings, to protect the
external surfaces of steel harbour installations and appurtenances from corrosion due to seawater,
brackish water, saline mud or soil fill.
Cathodic protection works by supplying sufficient direct current to the immersed external surface of
the structure to change the steel to electrolyte potential to values where corrosion is insignificant.
The general principles of cathodic protection in seawater are detailed in ISO 12473. The general
principles of cathodic protection in soils are detailed in EN 12954.
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SIST EN ISO 13174:2013
INTERNATIONAL STANDARD ISO 13174:2012(E)
Cathodic protection of harbour installations
1 Scope
1.1 General
This International Standard defines the means to be used to ensure that cathodic protection is efficiently
applied to the immersed and driven/buried metallic external surfaces of steel port, harbour, coastal and flood
defence installations and appurtenances in seawater and saline mud to provide protection from corrosion.
1.2 Structures
This International Standard specifies cathodic protection of fixed and floating port and harbour
structures. This includes piers, jetties, dolphins (mooring and berthing), sheet or tubular piling, pontoons,
buoys, floating docks, lock and sluice gates. It also specifies cathodic protection of the submerged areas
of appurtenances, such as chains attached to the structure, when these are not electrically isolated from
the structure.
This International Standard is to be used in respect of cathodic protection systems where the anodes are
exposed to water or saline mud. For buried areas, typically in soil or sand filled areas behind piled walls
or within filled caissons, which may be significantly affected by corrosion, specific cathodic protection
design and operation requirements are defined in EN 12954, the anodes being exposed to soils.
This International Standard does not cover the cathodic protection of fixed or floating offshore structures
(including offshore loading buoys), submarine pipelines or ships.
This International Standard does not include the internal protection of surfaces of any components such
as ballast tanks, internals of floating structures flooded compartments of lock and sluice gates or the
internals of tubular steel piles.
1.3 Materials
This International Standard covers the cathodic protection of structures fabricated principally from
bare or coated carbon and carbon manganese steels.
As some parts of the structure may be made of metallic materials other than carbon steels, the cathodic
protection system should be designed to ensure that there is a complete control over any galvanic coupling
and minimize risks due to hydrogen embrittlement or hydrogen-induced cracking (see ISO 12473).
This International Standard does not address steel reinforced concrete structures (see ISO 12696).
1.4 Environment
This International Standard is applicable to the whole submerged zone in seawater, brackish waters and
saline mud and related buried areas which can normally be found in port, harbour, coastal and flood
defence installations wherever these structures are fixed or floating.
For surfaces which are alternately immersed and exposed to the atmosphere, the cathodic protection
is only effective when the immersion time is long enough for the steel to become polarized. Typically,
effective cathodic protection is achieved for all surfaces below mid tide.
For structures such as sheet steel and tubular steel piles that are driven into the sea bed or those that
are partially buried or covered in mud, this International Standard is also applicable to the surfaces
buried, driven and exposed to mud which are intended to receive cathodic protection along with surfaces
immersed in water.
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Cathodic protection may also be applied to the rear faces of sheet steel piled walls and the internal
surfaces of filled caissons. Cathodic protection of such surfaces is specified by EN 12954.
This International Standard is applicable to those structures which are, or may be in the future, affected
by “Accelerated Low Water Corrosion” (ALWC) and other more general forms of microbial corrosion
(MIC) or other forms of so-called “concentrated corrosion” associated with galvanic couples, differential
aeration and other local corrosion influencing parameters
NOTE Information is available in BS 6349-1:2000, Clause 59 and CIRIA C634 (see Bibliography)
1.5 Safety and environment protection
This International Standard does not address safety and environmental protection aspects associated
with cathodic protection to which national or international regulations apply.
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 12473, General principles of cathodic protection in sea water
EN 12496, Galvanic anodes for cathodic protection in seawater and saline mud
ISO 12696, Cathodic protection of steel in concrete
EN 12954, Cathodic protection of buried or immersed metallic structures – General principles and application
for pipelines
EN 13509, Cathodic protection measurement techniques
EN 50162, Protection against corrosion by stray current from direct current systems
3 Terms and definitions
For the purposes of this document, the terms and definitions in ISO 12473 and the following apply.
3.1
accelerated low water corrosion
ALWC
localised corrosion generally found on the sea side at or just below the LAT level of structures, but can
be present at all immersed levels
Note 1 to entry: This phenomenon is associated with microbiologically influenced corrosion (MIC) and generally
quiescent conditions. (See CIRIA C634.) Corrosion rates, without cathodic protection, can be as high as 2 mm/side/
year and the corrosion is typically localized as large, open pitting
3.2
atmospheric zone
zone located above the splash zone, i.e. above the level reached by the normal swell, whether the
structure is moving or not
3.3
buried zone
zone located under the mud line or in soil or fill
3.4
cathodic protection zone
that part of the structure which can be considered independently with respect to cathodic protection design
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ISO 13174:2012(E)
3.5
coating breakdown factor
F
ratio of cathodic current density for a coated metallic material to the cathodic current density of the
bare material
3.6
driving voltage
difference between the structure/electrolyte potential and the anode/electrolyte potential when the
cathodic protection is operating
3.7
HAT
level of highest astronomical tide
3.8
immersed zone
zone located above the mud line and below the extended tidal zone or the water line at a draught
corresponding to the normal working conditions
3.9
LAT
level of lowest astronomical tide
3.10
MTL
mean tide level (also known as MSL mean sea level or MWL mean water level)
3.11
microbial corrosion
corrosion associated with the action of micro-organisms present in the corrosion system
Note 1 to entry: Also called microbiologically influenced corrosion (MIC).
3.12
ROV
remotely operated vehicle
3.13
piling
foundation, tubular or sheet steel element forming part or whole of a harbour structure
3.14
splash zone
the elevation of the structure which is intermittently wet and dry due to the wave action just above the HAT
3.15
submerged zone
zone including the buried zone, the immersed zone, the transition
zone and the lower part of the tidal zone under the MWL
See Figure 1.
3.16
transition zone
zone located below LAT and including the possible level inaccuracy of the structure installation which is
affected by a higher oxygen content due to normal swell or tidal movement
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ISO 13174:2012(E)
Figure 1 — Schematic representation of levels and zones in seawater environment
4 Competence of personnel
Personnel who undertake the design, supervision of installation, commissioning, supervision of
operation, measurements, monitoring and supervision of maintenance of cathodic protection systems
shall have the appropriate level of competence for the tasks undertaken. This competence should be
independently assessed and documented.
NOTE 1 EN 15257 constitutes a suitable method of assessing and certifying competence of cathodic protection
personnel which may be utilized.
NOTE 2 Competence of cathodic protection personnel to the appropriate level for tasks undertaken should be
demonstrated by certification in accordance with EN 15257 or by another equivalent prequalification procedure.
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5 Design basis
5.1 Objectives
The objective of a cathodic protection system is to deliver sufficient current to each part of the structure
and appurtenances and to distribute this current so that the steel/water potential of each part of the
structure is within the limits given by the protection criteria (see 5.2).
Steel/water potentials should be as uniform as possible over the whole structure. This may be achieved
only if distribution of the protective current over the structure during normal service conditions allows.
Uniform levels of cathodic protection may be difficult to achieve in some areas or parts of structures
such as chains, for which a supplementary cathodic protection system may be considered if it is intended
to attempt to provide full cathodic protection to them.
The cathodic protection system for a fixed or floating structure belonging to harbour installations may
be combined with a coating system, even though some appurtenances, such as chains, may not benefit
from the use of coatings. Extensive coating damage may also occur to buried areas of piles and steel
sheet pile walls which are driven into position during installation.
Dielectric shields may be used in conjunction with anodes; particularly impressed current anodes, to
minimize the risk of local over-protection and to improve the distribution of current from the anodes.
The cathodic protection system should be designed either for the life time of the structure or for a period
corresponding to a planned maintenance or (if applicable) dry-docking interval. Alternatively when it
is not feasible to design the cathodic protection system for the life of the structure or if dry-docking is
not possible, the system should be designed for easy replacement of cathodic protection components,
typically using divers or a ROV.
The above objectives should be achieved by the design of a cathodic protection system using impressed
current or galvanic anode systems or a combination of both.
The design, the installation, the energising, the commissioning, the long-term operation and the
documentation of all of the elements of cathodic protection systems shall be fully recorded.
Each step shall be undertaken in accordance with a fully documented quality plan.
NOTE ISO 9001 constitutes a suitable Quality Management Systems Standard which may be utilized.
Each stage of the design shall be checked and the checking shall be documented.
Each stage of the installation, energising, commissioning and operation shall be the subject of appropriate
visual, mechanical and/or electrical testing and all testing shall be documented.
All test instrumentation shall have valid calibration certificates traceable to national or International
Standards of calibration.
The documentation shall constitute part of the permanent records for the works.
5.2 Cathodic protection criteria
The criteria for cathodic protection are detailed in ISO 12473.
The criterion for protection of steel in aerobic seawater is a polarized potential more negative than
−0,80 V measured with respect to silver/silver chloride/seawater reference electrode (Ag/AgCl/seawater
reference electrode). This corresponds approximately to + 0,23 V when measured with respect to pure
zinc electrode (e.g. alloy type Z2 as defined in EN 12496) or + 0,25 V when measured with respect to zinc
electrode made with galvanic anode alloy types Z1, Z3 or Z4 as specified in EN 12496.
The criterion for protection of steel in anaerobic environments in seawater and sea bed muds which
contain active sulfate reducing bacteria or support other microbial corrosion (MIC) species, including
those associated with Accelerated Low Water Corrosion (ALWC), is a polarized potential more negative
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ISO 13174:2012(E)
than −0,90 V measured with respect to silver/silver chloride/seawater reference electrode (Ag/AgCl/
seawater reference electrode).
A negative limit of −1,10 V (Ag/AgCl/seawater reference electrode) is generally recommended to prevent
coating disbondment and/or increase in fatigue propagation rates.
Where there is a possibility of hydrogen embrittlement of steels or other metals which may be adversely
affected by cathodic protection to excessively negative values, an additional less negative potential limit
shall be defined and observed. If not enough documented for a given material, this specif
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