1、Ductile iron pipes, fittings, accessories and their joints External zinc-based coatingPart 1: Metallic zinc with finishing layerBS ISO 81791:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06 ISO 2017Ductile iron pipes, fittings, accessories and their joints Extern
2、al zinc-based coating Part 1: Metallic zinc with finishing layerTuyaux, raccords et accessoires en fonte ductile et leurs assemblages Revtement extrieur base de zinc Partie 1: Zinc mtallique avec couche de finitionINTERNATIONAL STANDARDISO8179-1Third edition2017-07Reference numberISO 8179-1:2017(E)N
3、ational forewordThis British Standard is the UK implementation of ISO 81791:2017. It supersedes BS ISO 81791:2004, which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PSE/10, Iron pipes and fittings.A list of organizations represented on this committee can
4、 be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 93432 2ICS 23.040.10Compli
5、ance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 September 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS ISO 81791:2017 ISO
6、 2017Ductile iron pipes, fittings, accessories and their joints External zinc-based coating Part 1: Metallic zinc with finishing layerTuyaux, raccords et accessoires en fonte ductile et leurs assemblages Revtement extrieur base de zinc Partie 1: Zinc mtallique avec couche de finitionINTERNATIONAL ST
7、ANDARDISO8179-1Third edition2017-07Reference numberISO 8179-1:2017(E)BS ISO 81791:2017ISO 8179-1:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or util
8、ized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyrigh
9、t officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 81791:2017ISO 8179-1:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless other
10、wise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address b
11、elow or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgISO 8179-1:2017(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions . 14
12、Materials . 15 Zinc-based coating 25.1 Pipeline component surface condition 25.2 Method of application . 25.3 Coating characteristics . 25.4 Zinc-based coating mass . 25.5 Repairs to the zinc-based coating . 36 Finishing layer . 37 Test methods . 37.1 Determination of zinc-based coating mass 37.2 De
13、termination of the dry film thickness of the finishing layer 4Annex A (informative) Field verification of the metallic zinc-based coating mass on a finished product 5Annex B (informative) Field of use in relation to the characteristics of soils 8Bibliography .10 ISO 2017 All rights reserved iiiConte
14、nts PageBS ISO 81791:2017ISO 8179-1:2017(E)ForewordISO (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
15、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 Electr
16、otechnical Commission (IEC) on all matters of electrotechnical 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
17、ISO documents should be noted. This document was drafted 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 hel
18、d responsible for identifying any or all such patent rights. 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 informat
19、ion given for the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO)
20、 principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 5, Ferrous metal pipes and metallic fittings, Subcommittee SC 2, Cast iron pipes, fittings and their joints.This third edition cance
21、ls and replaces the second edition (ISO 8179-1:2004), which has been technically revised. The following changes have been made: the minimum quantity of Zn has been increased from 130 g/m2to 200 g/m2; the revision recognizes the technological advancements in the field regarding zinc-based coatings to
22、 increase the lifetime and reliability of ductile iron pipelines, improving protection to different types of corrosion (including general and localized) and the use of new alloy enrichments.A list of all parts in the ISO 8179 series can be found on the ISO website.iv ISO 2017 All rights reservedBS I
23、SO 81791:2017ISO 8179-1:2017(E)ForewordISO (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 interes
24、ted 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 C
25、ommission (IEC) on all matters of electrotechnical 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 document
26、s should be noted. This document was drafted 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 responsibl
27、e for identifying any or all such patent rights. 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 fo
28、r the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles
29、in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 5, Ferrous metal pipes and metallic fittings, Subcommittee SC 2, Cast iron pipes, fittings and their joints.This third edition cancels and repla
30、ces the second edition (ISO 8179-1:2004), which has been technically revised. The following changes have been made: the minimum quantity of Zn has been increased from 130 g/m2to 200 g/m2; the revision recognizes the technological advancements in the field regarding zinc-based coatings to increase th
31、e lifetime and reliability of ductile iron pipelines, improving protection to different types of corrosion (including general and localized) and the use of new alloy enrichments.A list of all parts in the ISO 8179 series can be found on the ISO website.iv ISO 2017 All rights reserved INTERNATIONAL S
32、TANDARD ISO 8179-1:2017(E)Ductile iron pipes, fittings, accessories and their joints External zinc-based coating Part 1: Metallic zinc with finishing layer1 ScopeThis document specifies an external protective coating system which is factory applied to ductile iron pipeline components as specified in
33、 ISO 2531, ISO 7186 and ISO 16631. This coating system comprises an electro-deposited metallic zinc-based coating of pure metallic zinc with a purity of 99,99 %, zinc and aluminium alloy with or without other metals, or other zinc alloysfollowed by a finishing layer that can be bituminous paint or s
34、ynthetic resin compatible with zinc-based coating.NOTE ISO 8179-2 deals with zinc-rich paint coating.2 Normative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edi
35、tion cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 2808, Paints and varnishes Determination of film thickness3 Terms and definitionsNo terms and definitions are listed in this document.ISO and IEC maintain terminological d
36、atabases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp4 MaterialsThe coating materials shall be pure metallic zinc with a purity of 99,99 %, zinc and al
37、uminium alloy with or without other metals, or other zinc alloysfollowed by a finishing layer that can be bituminous paint or synthetic resin compatible with zinc-based layer. ISO 2017 All rights reserved 1BS ISO 81791:2017ISO 8179-1:2017(E)5 Zinc-based coating5.1 Pipeline component surface conditio
38、nThe pipeline component surface shall be dry and free from rust and any non-adhering particles or foreign matter such as oil or grease.The metallic zinc-based coating shall be applied to the as-cast annealed external surface of the pipeline component, or to a blast-cleaned or ground surface at the m
39、anufacturers discretion.5.2 Method of applicationThe metallic zinc-based coating shall be applied by a spraying process in which metallic zinc or zinc alloy is heated to a molten state and projected in small droplets by spray guns on to the pipeline component surface.The design and construction of t
40、he spray equipment are not within the scope of this document.5.3 Coating characteristicsThe metallic zinc-based coating shall cover the outside surface of the pipeline component and shall be free from such defects as bare patches or lack of adhesion.A spiralled appearance is permissible provided tha
41、t the zinc-based coating masses comply with the requirements of 5.4.The manufacturer shall define those coating irregularities which are considered not detrimental to the performance of the coating system.Damaged areas of zinc-based coating caused by handling are acceptable, provided that the area o
42、f damage is less than 5 cm2per square metre and that the minor dimension of the damaged area does not exceed 5 mm.Greater areas of damage shall be repaired in accordance with 5.5.5.4 Zinc-based coating massThe mean mass of zinc-based coating measured in accordance with 7.1 shall be as follows: not l
43、ess than 200 g/m2with a local minimum of 180 g/m2; in low corrosive areas, by agreement between the purchaser and the supplier, 130 g/m2of zinc with a local minimum of 110 g/m2; in case of very corrosive soils, the manufacturer and the purchaser may decide to use additional coating mass.The manufact
44、urer shall visually inspect each pipeline component for quality and uniformity of coating and shall carry out regular measurements of zinc-based coating masses in accordance with the method described in 7.1.The factory quality control tests ensure conformity to the standard. Factory quality control
45、tests shall be the sole determinant of coating thickness acceptance. Where informative field verification is required, one of the methods described in Annex A shall be agreed upon between the manufacturer and the purchaser.For the selection of coatings in relation to the characteristics of soils, An
46、nex B can be consulted.2 ISO 2017 All rights reservedBS ISO 81791:2017ISO 8179-1:2017(E)5 Zinc-based coating5.1 Pipeline component surface conditionThe pipeline component surface shall be dry and free from rust and any non-adhering particles or foreign matter such as oil or grease.The metallic zinc-
47、based coating shall be applied to the as-cast annealed external surface of the pipeline component, or to a blast-cleaned or ground surface at the manufacturers discretion.5.2 Method of applicationThe metallic zinc-based coating shall be applied by a spraying process in which metallic zinc or zinc al
48、loy is heated to a molten state and projected in small droplets by spray guns on to the pipeline component surface.The design and construction of the spray equipment are not within the scope of this document.5.3 Coating characteristicsThe metallic zinc-based coating shall cover the outside surface o
49、f the pipeline component and shall be free from such defects as bare patches or lack of adhesion.A spiralled appearance is permissible provided that the zinc-based coating masses comply with the requirements of 5.4.The manufacturer shall define those coating irregularities which are considered not detrimental to the performance of the coating system.Damaged areas of zinc-based coating caused by handling are acceptable, provided that the area of damage is less than 5 cm2per square metre and tha
