1、BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06Corrosion of metals and alloys - Determination of AC corrosion - Protection criteriaBS EN ISO 18086:2017National forewordThis British Standard is the UK implementation of EN ISO 18086:2017. It is identical to ISO 18086:
2、2015. It supersedes BS EN 15280:2013 and BS ISO 18086:2015, which are withdrawn.The UK participation in its preparation was entrusted to Technical Committee GEL/603, Cathodic protection.A list of organizations represented on this committee can be obtained on request to its secretary.This publication
3、 does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2018 Published by BSI Standards Limited 2018ISBN 978 0 580 92586 3ICS 77.060Compliance with a British Standard cannot confer immunity from leg
4、al obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 June 2015.Amendments/corrigenda issued since publicationDate Text affected30 April 2018 This corrigendum renumbers BS ISO 18086:2015 as BS EN ISO 18086:2017BRITISH STANDARDBS E
5、N ISO 18086:2017EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 18086September 2017ICS 77.060 Supersedes EN 15280:2013EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGCEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN Ref.
6、 No. EN ISO 18086:2017: EAll rights of exploitation in any form and by any means reserved worldwide for CEN national MembersCorrosion of metals and alloys - Determination of AC corrosion - Protection criteria (ISO 18086:2015)Corrosion des mtaux et alliages - Dtermination de la corrosion occasionne p
7、ar les courants alternatifs - Critres de protection (ISO 18086:2015)Korrosion von Metallen und Legierungen - Bestimmung der Wechselstromkorrosion - Schutzkriterien (ISO 18086:2015)This European Standard was approved by CEN on 23 August 2017.CEN members are bound to comply with the CEN/CENELEC Intern
8、al 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 C
9、EN 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 versi
10、ons.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, Po
11、land, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.English VersionISO 18086:2015Foreword vIntroduction vi1 Scope . 12 Normative references 13 Terms and definitions . 14 Cathodic protection persons competence 45 Assessment of the AC influence .
12、55.1 General . 55.2 Assessment of the level of interference . 56 Evaluation of the AC corrosion likelihood 66.1 Prerequisite . 66.1.1 General 66.1.2 AC voltage on the structure 66.2 AC and DC current density 76.2.1 General 76.2.2 AC current density 76.2.3 High cathodic DC current density . 76.2.4 Lo
13、w cathodic DC current density 76.2.5 Current ratio “Ia.c./Id.c” . 86.2.6 Soil resistivity . 86.3 Corrosion rate 86.4 Pipeline coatings . 86.5 Evaluation of the metal loss . 87 Acceptable interference levels . 88 Measurement techniques 98.1 Measurements . 98.1.1 General 98.1.2 Selection of test sites
14、 98.1.3 Selection of measurement parameter 108.1.4 Sampling rate for the recording of interference levels 108.1.5 Accuracy of measuring equipment108.1.6 Installation of coupons or probes to calculate current densities108.2 DC potential measurements . 108.3 AC voltage measurements 108.4 Measurements
15、on coupons and probes 118.4.1 Installation of coupons or probes 118.4.2 Current measurements118.4.3 Corrosion rate measurements. 128.5 Pipeline metal loss techniques . 139 Mitigation measures 139.1 General 139.2 Construction measures . 139.2.1 Modification of bedding material . 139.2.2 Installation
16、of isolating joints 139.2.3 Installation of mitigation wires 139.2.4 Optimization of pipeline and/or powerline route .149.2.5 Power line or pipeline construction.149.3 Operation measures 149.3.1 Earthing 149.3.2 Adjustment of cathodic protection level 159.3.3 Repair of coating defects 15ii ISO 2015
17、All rights reservedContents PageBS EN ISO 18086:2017ISO 18086:201510 Commissioning 1610.1 Commissioning 1610.2 Preliminary checking 1610.2.1 General. 1610.2.2 Coupon AC voltage and current startup .1710.2.3 Verification of effectiveness. 1710.2.4 Installation and commissioning documents .1711 Monito
18、ring and maintenance .17Annex A (informative) Simplified description of the AC corrosion phenomenon 19Annex B (informative) Coupons and probes 21Annex C (informative) Coulometric oxidation .26Annex D (informative) Influence of soil characteristics on the AC corrosion process .27Annex E (informative)
19、 Other criteria that have been used in the presence of AC influence 28Annex F (informative) Parameters to take into account to choose a DC decoupling device 32Annex G (informative) Method to determine the reference electrode location to remote earth .34Annex H (informative) Simultaneous measurement
20、on coupon current densities with high rate .36Bibliography .38 ISO 2015 All rights reserved iiiBS EN ISO 18086:2017ISO 18086:2015European forewordThe text of ISO 18086:2015 has been prepared by Technical Committee ISO/TC 156“Corrosion of metals and alloys” of the International Organization for Stand
21、ardization (ISO) and has been taken over as EN ISO 18086:2017 by Technical Committee CEN/TC 219 “Cathodic protection” the secretariat of which is held by BSI.This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the
22、latest by March 2018, and conflicting national standards shall be withdrawn at the latest by March 2018.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent right
23、s.According to the CEN-CENELEC Internal Regulations, the national standards organizations 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, G
24、ermany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.iv ISO 2015 All rights reservedBS EN ISO 18086:2017ISO 18086:2015ForewordISO (
25、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 commi
26、ttee 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 electrotec
27、hnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted
28、 in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).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
29、. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute
30、 an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT), see the following URL: Foreword Supplementary information.The committe
31、e responsible for this document is ISO/TC 156, Corrosion of metal and alloys. ISO 2015 All rights reserved vBS EN ISO 18086:2017ISO 18086:2015IntroductionThis International Standard has incorporated criteria and thresholds together with experience gained from the most recent data. Various countries
32、have a very different approach to the prevention of AC corrosion depending primarily on the DC interference situation. These different approaches are taken into account in two different ways either in presence of “low” on-potentials, which allows a certain level of AC voltage (up to 15 V), or in pre
33、sence of “high” on-potentials (with DC stray current interference on the pipeline for instance) which requires the reduction of the AC voltage towards the lowest possible levels.This International Standard also gives some parameters to consider when evaluating the AC corrosion likelihood, as well as
34、 detailed measurement techniques, mitigation measures, and measurements to carry out for commissioning of any AC corrosion mitigation system. Note that Annex E proposes other parameters and thresholds that require further validation based on practical experiences.vi ISO 2015 All rights reservedBS EN
35、 ISO 18086:2017Corrosion of metals and alloys - Determination of AC corrosion - Protection criteria1 ScopeThis International Standard is applicable to buried cathodically-protected pipeline that is influenced by AC traction systems and/or AC power lines.In the presence of AC interference, the protec
36、tion criteria given in ISO 15589-1 are not sufficient to demonstrate that the steel is being protected against corrosion.This International Standard provides limits, measurement procedures, mitigation measures, and information to deal with long term AC interference for AC voltages at frequencies bet
37、ween 16,7 and 60 Hz and the evaluation of AC corrosion likelihood.This International Standard deals with the possibility of AC corrosion of metallic pipelines due to AC interferences caused by inductive, conductive or capacitive coupling with AC power systems and the maximum tolerable limits of thes
38、e interference effects. It takes into account the fact that this is a long-term effect, which occurs during normal operating conditions of the AC power system.This International Standard does not cover the safety issues associated with AC voltages on pipelines. These are covered in national standard
39、s and regulations (see e.g. EN 50443).2 Normative referencesThe 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
40、) applies.ISO 15589-1, Petroleum, petrochemical and natural gas industries Cathodic protection of pipeline systems Part 1: On-land pipelinesISO 8044, Corrosion of metals and alloys Basic terms and definitionsIEC 61010-1, Safety requirements for electrical equipment for measurements, control, and lab
41、oratory use Part 1: General requirementsEN 13509, Cathodic protection measurement techniquesEN 15257, Cathodic protection Competence levels and certification of cathodic protection personnelEN 50443, Effects of electromagnetic interference on pipelines caused by high voltage AC electric traction sys
42、tems and/or high voltage AC power supply systems3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 8044 and the following apply.3.1AC electric traction systemAC railway electrical distribution network used to provide energy for rolling stockNote 1 to ent
43、ry: The system can comprise the following: contact line systems;INTERNATIONAL STANDARD ISO 18086:2015 ISO 2015 All rights reserved 1BS EN ISO 18086:2017ISO 18086:2015 return circuit of electric railway systems; running rails of non-electric railway systems, which are in the vicinity of and conductiv
44、ely connected to the running rails of an electric railway system.3.2AC power supply systemAC electrical system devoted to electrical energy transmission and includes overhead lines, cables, substations and all apparatus associated with them3.3AC power systemAC electric traction system or AC power su
45、pply systemNote 1 to entry: Where it is necessary to differentiate, each interfering system is clearly indicated with its proper term.3.4copper/copper sulfate reference electrodeCSEreference electrode consisting of copper in a saturated solution of copper sulfate3.5AC voltagevoltage measured to eart
46、h between a metallic structure and a reference electrode3.6interfering systemgeneral expression encompassing an interfering high voltage AC electric traction system and/or high voltage AC power supply system3.7interfered systemsystem on which the interference effects appearNote 1 to entry: In this I
47、nternational Standard, it is the pipeline system.3.8pipeline systemsystem of pipe network with all associated equipment and stationsNote 1 to entry: In this International Standard, pipeline system refers only to metallic pipeline system.Note 2 to entry: The associated equipment is the equipment elec
48、trically connected to the pipeline.3.9earthconductive mass of the earth, whose electric potential at any point is conventionally taken as equal to zeroSOURCE: IEC 60050 8263.10operating conditionfault-free operation of any systemNote 1 to entry: Transients are not to be considered as an operating co
49、ndition.2 ISO 2015 All rights reservedBS EN ISO 18086:2017ISO 18086:20153.11fault conditionnon-intended condition caused by short-circuit to earth, the fault duration being the normal clearing time of the protection devices and switchesNote 1 to entry: The short circuit is an unintentional connection of an energized conductor to earth or to any metallic part in contact with earth.3.12conductive couplingcoupling which occurs when a proportion of the current belonging to the interfering system returns to the system earth via the interfe
