1、Ductile iron pipes, fittings, accessories and their joints External zinc-based coating Part 1: Metallic zinc with finishing layer BS ISO 81791:2017 BSI Standards Publication WB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06 ISO 2017 Ductile iron pipes, fittings, accessories and their joints E
2、xternal zinc-based coating Part 1: Metallic zinc with finishing layer Tuyaux, raccords et accessoires en fonte ductile et leurs assemblages Revtement extrieur base de zinc Partie 1: Zinc mtallique avec couche de finition INTERNATIONAL STANDARD ISO 8179-1 Third edition 2017-07 Reference number ISO 81
3、79-1:2017(E) National foreword This 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 It supersedes BS ISO 81791:2004, which is withdrawn.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 t
4、his committee can 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 2017 ISBN 978 0 580 93432 2
5、 ICS 23.040.10 Compliance 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 publication Date Text affected BRITISH STAN
6、DARD BS ISO 81791:2017 ISO 2017 Ductile iron pipes, fittings, accessories and their joints External zinc-based coating Part 1: Metallic zinc with finishing layer Tuyaux, raccords et accessoires en fonte ductile et leurs assemblages Revtement extrieur base de zinc Partie 1: Zinc mtallique avec couche
7、 de finition INTERNATIONAL STANDARD ISO 8179-1 Third edition 2017-07 Reference number ISO 8179-1:2017(E) BS ISO 81791:2017 ISO 8179-1:2017(E)ii ISO 2017 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in Switzerland All rights reserved. Unless otherwise specified, no part of thi
8、s 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 below or ISOs member body in th
9、e country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.org BS ISO 81791:2017 ISO 8179-1:2017(E)ii ISO 2017 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2017, Publishe
10、d in Switzerland All rights reserved. Unless otherwise 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
11、 can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgISO 8179-1:2017(E)Foreword iv 1 Scop
12、e . 1 2 Normative references 1 3 Terms and definitions . 1 4 Materials . 1 5 Zinc-based coating 2 5.1 Pipeline component surface condition 2 5.2 Method of application . 2 5.3 Coating characteristics . 2 5.4 Zinc-based coating mass . 2 5.5 Repairs to the zinc-based coating . 3 6 Finishing layer . 3 7
13、 Test methods . 3 7.1 Determination of zinc-based coating mass 3 7.2 Determination of the dry film thickness of the finishing layer 4 Annex A (informative) Field verification of the metallic zinc-based coating mass on a finished product 5 Annex B (informative) Field of use in relation to the charact
14、eristics of soils 8 Bibliography .10 ISO 2017 All rights reserved iii Contents Page BS ISO 81791:2017 ISO 8179-1:2017(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International S
15、tandards 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, als
16、o take part in the work. ISO collaborates closely with the International Electrotechnical 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.
17、In particular the different approval criteria needed for the different types of 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 el
18、ements of this document may be the subject of patent rights. ISO shall not be held 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 recei
19、ved (see www .iso .org/ patents). Any trade name used in this document is information 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
20、, as well as information about ISOs adherence to the World Trade Organization (WTO) 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, Su
21、bcommittee SC 2, Cast iron pipes, fittings and their joints. This third edition cancels 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/m 2to 200 g/m 2 ; the revision
22、 recognizes the technological advancements in the field regarding zinc-based coatings to 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 i
23、n the ISO 8179 series can be found on the ISO website.iv ISO 2017 All rights reserved BS ISO 81791:2017 ISO 8179-1:2017(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International
24、 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, a
25、lso take part in the work. ISO collaborates closely with the International Electrotechnical 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
26、. In particular the different approval criteria needed for the different types of 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
27、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. 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 rec
28、eived (see www .iso .org/ patents). Any trade name used in this document is information 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 assessme
29、nt, as well as information about ISOs adherence to the World Trade Organization (WTO) 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,
30、Subcommittee SC 2, Cast iron pipes, fittings and their joints. This third edition cancels 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/m 2to 200 g/m 2 ; the revisi
31、on recognizes the technological advancements in the field regarding zinc-based coatings to 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
32、 in the ISO 8179 series can be found on the ISO website.iv ISO 2017 All rights reserved INTERNATIONAL ST ANDARD ISO 8179-1:2017(E) Ductile iron pipes, fittings, accessories and their joints External zinc-based coating Part 1: Metallic zinc with finishing layer 1 Scope This document specifies an exte
33、rnal protective coating system which is factory applied to ductile iron pipeline components as specified in 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 o
34、r without other metals, or other zinc alloys followed by a finishing layer that can be bituminous paint or synthetic resin compatible with zinc-based coating. NOTE ISO 8179-2 deals with zinc-rich paint coating. 2 Normative references The following documents are referred to in the text in such a way
35、that some or all of their content constitutes requirements 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 2808, Paints and varnishes Determination of film thickness
36、3 Terms and definitions No terms and definitions are listed in this document. ISO and IEC maintain terminological databases 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 :/ w
37、ww .iso .org/ obp 4 Materials The coating materials shall be pure metallic zinc with a purity of 99,99 %, zinc and aluminium alloy with or without other metals, or other zinc alloys followed by a finishing layer that can be bituminous paint or synthetic resin compatible with zinc- based layer. ISO 2
38、017 All rights reserved 1 BS ISO 81791:2017 ISO 8179-1:2017(E) 5 Zinc-based coating 5.1 Pipeline component surface condition The 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
39、 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 application The metallic zinc-based coating shall be applied by a spraying process in which metallic zinc or zinc alloy is heated to a m
40、olten 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 characteristics The metallic zinc-based coating shall cover the outside surface of the pipeline co
41、mponent 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 t
42、he 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 cm 2per square metre and that the minor dimension of the damaged area does not exceed 5 mm. Greater areas of damage shall be repaired in accord
43、ance with 5.5. 5.4 Zinc-based coating mass The mean mass of zinc-based coating measured in accordance with 7.1 shall be as follows: not less than 200 g/m 2with a local minimum of 180 g/m 2 ; in low corrosive areas, by agreement between the purchaser and the supplier, 130 g/m 2of zinc with a local mi
44、nimum of 110 g/m 2 ; in case of very corrosive soils, the manufacturer and the purchaser may decide to use additional coating mass. The manufacturer shall visually inspect each pipeline component for quality and uniformity of coating and shall carry out regular measurements of zinc-based coating mas
45、ses in accordance with the method described in 7.1. The factory quality control tests ensure conformity to the standard. Factory quality control tests shall be the sole determinant of coating thickness acceptance. Where informative field verification is required, one of the methods described in Anne
46、x A shall be agreed upon between the manufacturer and the purchaser. For the selection of coatings in relation to the characteristics of soils, Annex B can be consulted.2 ISO 2017 All rights reserved BS ISO 81791:2017 ISO 8179-1:2017(E) 5 Zinc-based coating 5.1 Pipeline component surface condition T
47、he 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 ma
48、nufacturers discretion. 5.2 Method of application The 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
49、 the spray equipment are not within the scope of this document. 5.3 Coating characteristics The 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 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
