1、BS ISO 28921-2:2015Industrial valves Isolatingvalves for low-temperatureapplicationsPart 2: Type testingBS EN ISO 28921-2:2017(ISO 28921-2:2015)BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN ISO 28921-2:2017 BRITISH STANDARDNational forewordThis British Standa
2、rd is the UK implementation of EN ISO 28921-2:2017. It is identical to ISO 28921-2:2015. It supersedes BS ISO 28921-2:2015 which is withdrawn. Together with BS EN ISO 28921-1:2017, it also supersedes BS EN 12567:2000 which is withdrawn.The UK participation in its preparation was entrusted by Technic
3、al Committee PSE/18, Industrial valves, steam traps, actuators and safety devices against excessive pressure, to Subcommittee PSE/18/1, Industrial valves, steam traps, actuators and safety devices against excessive pressure - Valves - Basic standards.A list of organizations represented on this subco
4、mmittee 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 2017ISBN 978 0 580 94528 1ICS 23.
5、060.01Compliance 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 November 2015.Amendments/corrigenda issued since publicationDate Text affected31 March 2017 This corrige
6、ndum renumbers BS ISO 28921-2:2015 as BS EN ISO 28921-2:2017EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 28921-2 February 2017 ICS 23.060.01 Supersedes EN 12567:2000English Version Industrial valves - Isolating valves for low-temperature applications - Part 2: Type testing (ISO 28921-2:2
7、015) Robinetterie industrielle - Robinets disolement pour application basses tempratures - Partie 2: Essais de type (ISO 28921-2:2015) Industriearmaturen - Absperrventile fr die Anwendung im Niedertemperaturbereich - Teil 2: Typprfung (ISO 28921-2:2015) This European Standard was approved by CEN on
8、10 January 2017. 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
9、 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 t
10、o 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,
11、 Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC M
12、anagement Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 28921-2:2017 EBS ISO 28921-2:2015ISO 28921-2:2015(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions
13、. 14 Test conditions . 24.1 Valve selection . 24.2 Testing criteria and selection of valve design . 24.2.1 General 24.2.2 Representative valve design selection. 34.2.3 Selection and qualification of sealing elements 34.3 Requirements for test valve, direction for installation and conditions 34.4 Pre
14、paration for low temperature test . 34.4.1 General 34.4.2 Valve tests 34.4.3 Test equipment 35 Low temperature testing requirements . 45.1 Safety provisions . 45.2 Cooling of the valve . 45.3 Test gas 45.4 Equipment . 45.4.1 General 45.4.2 Test equipment 65.4.3 Instruments calibration . 66 Informati
15、on to be supplied by the purchaser. 6Annex A (normative) Test procedure for type testing of valves at low temperature . 7Annex B (informative) Information to be supplied by the purchaser .13Annex C (informative) Low-temperature type test record 14Bibliography .18 ISO 2015 All rights reserved iiiCont
16、ents PageEN ISO 28921-2:2017 (E) 3 European foreword The text of ISO 28921-2:2015 has been prepared by Technical Committee ISO/TC 153 “Valves” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 28921-2:2017 by Technical Committee CEN/TC 69 “Industrial valve
17、s” the secretariat of which is held by AFNOR. 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 August 2017, and conflicting national standards shall be withdrawn at the latest by August 2017. Atten
18、tion 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. EN ISO 28921-1 and EN ISO 28921-2 supersede EN 12567:2000. According to the CEN-CENELEC Int
19、ernal 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, Germany, Greece, Hungary, Iceland,
20、Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 28921-2:2015 has been approved by CEN as EN ISO 28921-2:2017 without any mod
21、ification. BS EN ISO 28921-2:2017EN ISO 28921-2:2017 (E)BS ISO 28921-2:2015ISO 28921-2:2015(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Test conditions . 24.1 Valve selection . 24.2 Testing criteria and selection of valve design . 24.2.1 General 24.2.2 Representative
22、 valve design selection. 34.2.3 Selection and qualification of sealing elements 34.3 Requirements for test valve, direction for installation and conditions 34.4 Preparation for low temperature test . 34.4.1 General 34.4.2 Valve tests 34.4.3 Test equipment 35 Low temperature testing requirements . 45
23、.1 Safety provisions . 45.2 Cooling of the valve . 45.3 Test gas 45.4 Equipment . 45.4.1 General 45.4.2 Test equipment 65.4.3 Instruments calibration . 66 Information to be supplied by the purchaser. 6Annex A (normative) Test procedure for type testing of valves at low temperature . 7Annex B (inform
24、ative) Information to be supplied by the purchaser .13Annex C (informative) Low-temperature type test record 14Bibliography .18 ISO 2015 All rights reserved iiiContents PageBS EN ISO 28921-2:2017ISO 28921-2:2015(E)BS ISO 28921-2:2015ISO 28921-2:2015(E)ForewordISO (the International Organization for
25、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 r
26、ight 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.The procedur
27、es 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 in accordance with the editorial r
28、ules 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. Details of any patent rights iden
29、tified 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 an endorsement.For an explanation
30、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 informationThe committee responsible for this document is
31、Technical Committee ISO/TC 153, Valves, Subcommittee SC 1, Design, manufacture, marking and testing.ISO 28921 consists of the following parts, under the general title Industrial valves Isolating valves for low-temperature applications: Part 1: Design, manufacturing and production testing Part 2: Typ
32、e testingiv ISO 2015 All rights reservedBS ISO 28921-2:2015INTERNATIONAL STANDARD ISO 28921-2:2015(E)Industrial valves Isolating valves for low-temperature applications Part 2: Type testingWARNING Persons using this International Standard should be familiar with normal laboratory practice. This Inte
33、rnational Standard does not purport to address all of the safety issues, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory requirements.1 ScopeThis part of ISO 28921 specifi
34、es requirements for the type testing of isolating valves for low-temperature applications to verify the performance of valves at a low temperature from 50 C down to 196 C.NOTE Nominal sizes (DN), nominal pipe sizes (NPS), nominal pressure (PN) and Classes are covered in ISO 28921-1.This part of ISO
35、28921 does not evaluate valve actuators unless they are integral part of the valve. Valves during testing can be operated manually or an actuator can be used during the testing. The effect of cold gas vapours during testing is taken into consideration in particular if the actuator is mounted directl
36、y over the test stand with the cold gases engulfing the actuator.This part of ISO 28921 does not apply to valves for cryogenic services, designed in accordance with ISO 21011, used with cryogenic vessels.2 Normative referencesThe following referenced documents, in whole or in part, are normatively r
37、eferenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 5208, Industrial valves Pressure testing of metallic valvesISO 2892
38、1-1, Industrial valves Isolating valves for low-temperature applications Part 1: Design, manufacturing and production testingASME B31.3, Process PipingEN 13480-2, Metallic industrial piping Part 2: Materials3 Terms and definitionsFor the purposes of this document, the terms and definitions given in
39、ISO 28921-1 and the following apply.3.1symmetric seated valvevalve with an internal construction which has a plane of symmetry perpendicular to the axis of the body endsNote 1 to entry: This is a valve where both seat sealing elements are identical. ISO 2015 All rights reserved 1BS EN ISO 28921-2:20
40、17ISO 28921-2:2015(E)BS ISO 28921-2:2015ISO 28921-2:2015(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 committe
41、es. 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 Inte
42、rnational 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. In particular the different approval criteria needed for the dif
43、ferent 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 elements of this document may be the subject of patent rights. ISO sha
44、ll 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 received (see www.iso.org/patents).Any trade name used in this document i
45、s information given for the convenience of users and does not constitute 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)
46、 see the following URL: Foreword - Supplementary informationThe committee responsible for this document is Technical Committee ISO/TC 153, Valves, Subcommittee SC 1, Design, manufacture, marking and testing.ISO 28921 consists of the following parts, under the general title Industrial valves Isolatin
47、g valves for low-temperature applications: Part 1: Design, manufacturing and production testing Part 2: Type testingiv ISO 2015 All rights reservedBS ISO 28921-2:2015INTERNATIONAL STANDARD ISO 28921-2:2015(E)Industrial valves Isolating valves for low-temperature applications Part 2: Type testingWARN
48、ING Persons using this International Standard should be familiar with normal laboratory practice. This International Standard does not purport to address all of the safety issues, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practic
49、es and to ensure compliance with any national regulatory requirements.1 ScopeThis part of ISO 28921 specifies requirements for the type testing of isolating valves for low-temperature applications to verify the performance of valves at a low temperature from 50 C down to 196 C.NOTE Nominal sizes (DN), nominal pipe sizes (NPS), nominal pressure (PN) and Classes are covered in ISO 28921-1.This part of ISO 28921 does not evaluate valve actuators unless they are integral part of the valve. Valves during testing can be op
