ISO INTERNATIONAL STANDARD 28721-4 Secondedition 2015-11-01 Vitreous and porcelain enamels Glass-lined apparatus for process plants - Part 4: Quality requirements for glass-lined flanged steel pipes and flanged steel fittings Emaux vitrifiés - Appareils émailles pour les installations industrielles- Partie 4: Exigences de qualite pour les tubes et raccords a brides en acierémaille Reference number ISO 28721-4:2015(E) SO anizationfor Standardization @ IS0 2015 International Org STANDARDIZATION C15956617 ithout license from IHS IS0 28721-4:2015(E) COPYRIGHTPROTECTEDDOCUMENT IS0 2015, 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. ISO copyrightoffice Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +41 22 749 09 47 [email protected] www.iso.org PrganizationforStandardization icensee-ZHEJIANG INST OF STANDARDIZoISQ s1.5 - All rights reserved Not for Resale, 2016/1/8 02:11:28 etworking permitted without license from IHS IS0 28721-4:2015(E) Contents Page Foreword ..iv 1 Scope 2 Normative references 3 Terms and definitions. 4 Materials for steel parts 5 Information to be supplied by the purchaser. ..2 6 Requirements 2 6.1 Requirements for the steel parts 2 6.1.1 Welding .2 6.1.2 Material properties. 2 6.1.3 Surface characteristics .3 6.1.4 Exterior protection 3 6.2 Requirements for the glass-lined components 3 6.2.1 Surfaces 3 6.2.2 Enamel defects. .3 6.2.3 Foreign matter in the enamel. 3 6.2.4 Enamel coating thickness. .4 6.2.5 Dimensions and tolerances. ..4 6.2.6 Other requirements. .4 7 Tests and certificates. .4 7.1 General ..4 7.2 Place of testing ..4 7.3 Testing of the substrate 7.4 Testing of the glass-lined components. .4 8 Marking 5 iii See=ZHEJIANG INST OF STANDARDIZATION C1 5956617 vided by IHS under lic ithout license from IHS Not for Resale, 2016/1/8 02:11:28