ISO INTERNATIONAL STANDARD 4991 Third edition 2015-12-15 Steel castings for pressure purposes Pieces moulees enacierpourservice sous pression Referencenumber IS04991:2015(E) ISO Intemational Organization:for Standardization =ZHEJIANG INST OF STANDARDIZATION C1 5956617 @IS02015 ed without license from IHS IS0 4991:2015(E) COPYRIGHTPROTECTEDDOCUMENT IS02015,Published 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 can be requested from either ISO at the address below or ISO's member body in the country of the requester. ISOcopyrightoffice Ch. de Blandonnet 8.CP 401 CH-1214 Vernier, Geneva, Switzerland Tel.+4122 749 0111 Fax +4122749 0947 [email protected] www.iso.org Licensee-ZHEJIANG INST.OF STANDARDIZAoISQ095-All rights reserved etwojking permitted without license from IHS Not for Resale, 2016/3/29 05:06:03 IS0 4991:2015(E) Contents Page Foreword ..iv 1 Scope ..1 2 Normative references 3 Termsanddefinitions ..1 4 Informationtobesuppliedbythepurchaser 5 Heat treatment .1 6 Welding. .2 7 Requirements .2 7.1 Chemical composition .2 7.2 Mechanicalproperties .2 8 Inspection and testing .2 8.1 General .2 8.2 Sampling. .3 8.3 Formation of test lots .3 8.4 Non-destructivetesting. .3 8.5 Marking. .3 9 Supplementaryrequirements .3 AnnexA(normative)Supplementaryrequirements .11 Annex B (informative) Welding conditions ..14 AnnexC (informative)Creepproperties ..15 Annex D (informative) UNS castgrades similar toISO castgrades .17 Bibliography .19 iii 2e=ZHEJIANG INSTOFSTANDARDIZATIONC15956617 lout license from IHS