1、May 2017 English price group 13No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 23.060.01!%dp“2659677www.din.deDIN E
2、N ISO 28921-2Industrial valves Isolating valves for lowtemperature applications Part 2: Type testing (ISO 289212:2015);English version EN ISO 289212:2017,English translation of DIN EN ISO 28921-2:2017-05Industriearmaturen Absperrventile fr die Anwendung im Tieftemperaturbereich Teil 2: Typprfung (IS
3、O 289212:2015);Englische Fassung EN ISO 289212:2017,Englische bersetzung von DIN EN ISO 28921-2:2017-05Robinetterie industrielle Robinets disolement pour application basses tempratures Partie 2: Essais de type (ISO 289212:2015);Version anglaise EN ISO 289212:2017,Traduction anglaise de DIN EN ISO 28
4、921-2:2017-05Together with DIN EN ISO 289211:201705,supersedesDIN EN 12567:200010www.beuth.deDocument comprises 26 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.05.17 DIN EN ISO 28921-2:2017-05 2 A comma is used as the decima
5、l marker. National foreword The text of ISO 28921-2:2015 has been prepared by Technical Committee ISO/TC 153 “Valves” and has been taken over as EN ISO 28921-2:2017 by Technical Committee CEN/TC 69 “Industrial valves” (Secretariat: AFNOR, France). The responsible German body involved in its preparat
6、ion was DIN-Normenausschuss Armaturen (DIN Standards Committee Valves), Working Committee NA 003-01-10 AA “Safety devices for the prevention of excessive pressure”. The DIN Standards corresponding to the International Standards referred to in this document are follows: ISO 6708 DIN EN ISO 6708 ISO 1
7、0434 DIN EN ISO 10434 ISO 10497 DIN EN ISO 10497 ISO 15761 DIN EN ISO 15761 ISO 17292 DIN EN ISO 17292 ISO 28921-1 DIN EN ISO 28921-1 Amendments This standard differs from DIN EN 12567:2000-10 as follows: a) requirements from DIN EN 12567:2000-10 have been brought in line with DIN EN ISO 28921-1 and
8、 DIN EN ISO 28921-2; Previous editions DIN EN 12567: 2000-10 DIN EN ISO 28921-2:2017-05 3 National Annex NA (informative) Bibliography DIN EN ISO 6708, Pipework components Definition and selection of DN (nominal size) DIN EN ISO 10434, Bolted bonnet steel gate valves for the petroleum, petrochemical
9、 and allied industries DIN EN ISO 10497, Testing of valves Fire type-testing requirements DIN EN ISO 15761, Steel gate, glob and check valves for sizes DN 100 and smaller, for the petroleum and natural gas industries DIN EN ISO 17292, Metal ball valves for petroleum, petrochemical and allied industr
10、ies DIN EN ISO 28921-1, Industrial valves Isolating valves for low-temperature applications Part 1: Design, manufacturing and production testing DIN EN ISO 28921-2:2017-05 4 This page is intentionally left blank EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 28921-2 February 2017 ICS 23.06
11、0.01 Supersedes EN 12567:2000English Version Industrial valves - Isolating valves for low-temperature applications - Part 2: Type testing (ISO 28921-2:2015) Robinetterie industrielle - Robinets disolement pour application basses tempratures - Partie 2: Essais de type (ISO 28921-2:2015) Industriearma
12、turen - Absperrventile fr die Anwendung im Tieftemperaturbereich - Teil 2: Typprfung (ISO 28921-2:2015) This European Standard was approved by CEN on 10 January 2017. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Sta
13、ndard 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 (Engli
14、sh, 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, B
15、ulgaria, 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, Serbia, Slovakia, Slovenia, Spain, Sweden, Swit
16、zerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN nation
17、al Members. Ref. No. EN ISO 28921-2:2017 EEN ISO 28921-2:2017 (E) 2 Contents Page European foreword . 3 Foreword 4 1 Scope 5 2 Normative references 5 3 Terms and definitions . 5 4 Test conditions . 6 4.1 Valve selection . 6 4.2 Testing criteria and selection of valve design 6 4.2.1 General 6 4.2.2 R
18、epresentative valve design selection 7 4.2.3 Selection and qualification of sealing elements . 7 4.3 Requirements for test valve, direction for installation and conditions 7 4.4 Preparation for low temperature test . 7 4.4.1 General 7 4.4.2 Valve tests 7 4.4.3 Test equipment 7 5 Low temperature test
19、ing requirements . 8 5.1 Safety provisions . 8 5.2 Cooling of the valve . 8 5.3 Test gas . 8 5.4 Equipment . 8 5.4.1 General 8 5.4.2 Test equipment . 10 5.4.3 Instruments calibration . 10 6 Information to be supplied by the purchaser 10 Annex A (normative) Test procedure for type testing of valves a
20、t low temperature . 11 A.1 General . 11 A.2 Test procedures 11 A.2.1 Testing flow chart 11 A.2.2 Ambient temperature test 12 A.2.3 Low-temperature test . 13 A.2.4 Warm-up procedure and post-test examination 15 A.3 Test temperatures . 15 A.3.1 Ambient temperature . 15 A.3.2 Low temperature 15 A.4 Tes
21、t pressures . 15 A.4.1 Low-pressure seat test . 15 A.4.2 Incremental high-pressure seat test . 15 A.5 Duration of seat test 16 A.6 Direction of seat test . 16 A.7 Allowable seat leakage rates 16 Annex B (informative) Information to be supplied by the purchaser 17 Annex C (informative) Low-temperatur
22、e type test record 18 Bibliography . 22 DIN EN ISO 28921-2:2017-05 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 Commi
23、ttee CEN/TC 69 “Industrial valves” 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
24、the latest by August 2017. 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. EN ISO 28921-1 and EN ISO 28921-2 supersede EN 12567:2000.
25、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, Ger
26、many, 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. Endorsement notice The text of ISO 28921-2:2015 has been approved by CEN as EN
27、ISO 28921-2:2017 without any modification. EN ISO 28921-2:2017 (E)DIN EN ISO 28921-2:2017-05 3 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 carrie
28、d 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. IS
29、O 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. In particular the different
30、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 elements of this document may be t
31、he 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 received (see www.iso.org/patents).An
32、y 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 meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in t
33、he Technical Barriers to Trade (TBT) 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 gene
34、ral title Industrial valves Isolating valves for low-temperature applications: Part 1: Design, manufacturing and production testing Part 2: Type testingEN ISO 28921-2:2017 (E)DIN EN ISO 28921-2:2017-05 4WARNING Persons using this International Standard should be familiar with normal laboratory pract
35、ice. 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 practices and to ensure compliance with any national regulatory requirements.1 ScopeThis part of ISO
36、 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.Thi
37、s part of ISO 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 m
38、ounted directly 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
39、 normatively referenced 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
40、valvesISO 28921-1, 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 definit
41、ions given in 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.EN ISO 28921-2:2017 (E)DIN EN ISO 289
42、21-2:2017-05 5 3.2asymmetric seated valvevalve with an internal construction which has no plane of symmetry perpendicular to the axis of the body endsNote 1 to entry: This is a valve with a single seat offset from the shaft centreline.3.3design familyvalves of the same type for which the basic desig
43、n for the outside pressure retaining envelope, in particular the body construction, is the same design for all sizes of the valve range and the same stem movementNote 1 to entry: Valves of the same type include, for example, gate, globe, ball valves.Note 2 to entry: Examples of body construction inc
44、lude one piece, two piece or three piece body, bonnet extension.Note 3 to entry: Examples of stem movement include raising and not rotating.Note 4 to entry: Valves are considered to be of the same design family if they can all be depicted on one dimensionless cross-sectional drawing, with all the ex
45、ternal dimensions added in a table on the same drawing.3.4cold working pressureCWPmaximum fluid pressure assigned to a valve for operation at a fluid temperature up to 38 C3.5operational cyclemotion of the stem that moves a valve obturator from the fully closed position to the fully open position an
46、d returns to the fully closed positionNote 1 to entry: For check valves, an operational cycle is when the obturator moves from the closed position to open and back to the closed position.4 Test conditions4.1 Valve selectionInspection and testing under this part of ISO 28921 shall be carried out on a
47、 randomly selected production valve of a design family and of a particular material of construction. Size selection shall be at mid-range of the design range, the valve PN or Class shall be selected so that it qualifies all valves of the same PN or Class and all valves of the lower PN or Class as lo
48、ng as the valves are of an identical design. Valves of the same design family and the same materials of construction tested at lower temperature qualify valves for applications at higher temperatures up to ambient temperature.NOTE The mid-range valve size selected for testing varies with the size ra
49、nge available from the valve manufacturer. For example, if the valve offering of a particular valve design is DN 50, DN 65, DN 80, DN 100, DN 150 and DN 200 or NPS 2, NPS 2 , NPS 3, NPS 4, NPS 6 and NPS 8, the mid-range valve selected for testing is DN 80 or DN 100, and for NPS valves, it is NPS 3 or NPS 4. Either of the two sizes is acceptable. Alternatively, the size to be tested can be decided by an agreement between the manufacturer an
