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This document (EN ISO 28721-4:2015) specifies the quality requirements for glass-lined flanged steel pipes and flanged steel fittings used for process plants. The International Standard ISO 28721-4:2015 has been prepared by Technical Committee ISO/TC 107 "Metallic and other inorganic coatings" in collaboration with Technical Committee CEN/TC 262 "Metallic and other inorganic coatings", the secretariat of which is held by BSI (United Kingdom). The responsible German committee is Working Committee NA 062-01-63 AA "Prüfung von Emails und Emaillierungen" ("Testing of vitreous and porcelain enamels") at DIN Standards Committee Materials Testing (NMP).
This document replaces DIN EN ISO 28721-4:2013-03 .