DIN EN ISO 28921-1-2017 工业阀门.低温用隔离阀门.第1部分:设计、制造及产品检测(ISO 28921-1-2013);德文版本EN ISO 28921-1-2017
Industrial valves - Isolating valves for low-temperature applications - Part 1: Design, manufacturing and production testing (ISO 28921-1:2013); German version EN ISO 28921-1:2017