ISO INTERNATIONAL STANDARD 28921-2 First edition 2015-11-01 Industrial valves Isolating valves for low-temperature applications - Part 2: Type testing Robinetterie industrielle-Robinets d'isolement pour application a bassestempératures- Partie2:Essais de type Reference number IS028921-2:2015(E) ISO Intemational Organization for Standardization @IS02015 ted without license from IHS IS028921-2:2015(E) COPYRIGHTPROTECTEDDOCUMENT IS02015,Published inSwitzerland 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 can be requested from either ISO at the address below or ISO's 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 +4122 749 09 47 [email protected] www.iso.org Intemationaibr PrganizationforStandardization Uicensee-ZHEJIANG INST OF STANDARDIZAoISQ,5-All rights reserved etworking permitted without license from IHS IS0 28921-2:2015(E) Contents Page Foreword ..iv 1 Scope ..1 2 Normative references 3 Terms and definitions 4 Test conditions. .2 4.1 Valveselection 2 4.2 Testing criteria and selection of valvedesign .2 4.2.1 General 4.2.2 Representativevalvedesign selection. 4.2.3 Selectionandqualificationofsealingelements 3 4.3 Requirementsfortest valve,directionforinstallation and conditions. .3 4.4 Preparation forlowtemperature test. 3 4.4.1 General 3 4.4.2 Valvetests 3 4.4.3 Test equipment. .3 Low temperature testing requirements .4 5.1 Safety provisions .4 5.2 Cooling of the valve .4 5.3 Test gas .4 5.4 Equipment. 4 5.4.1 General .4 5.4.2 Test equipment. 6 5.4.3 Instrumentscalibration .6 6 Information tobe supplied by the purchaser .6 AnnexA (normative)Testprocedurefortypetestingofvalvesatlowtemperature AnnexB (informative) Information tobe suppliedbythepurchaser ..13 AnnexC (informative)Low-temperaturetypetestrecord ..14 Bibliography ..18 iii See=ZHEJIANG INSTOFSTANDARDIZATIONC15956617 thout license from IHS