阀门标准 BS EN 12351-1999 工业阀门 带法兰连接的阀门保护帽Industrial valves. Protective caps for valves with flanged connections .pdf [db:摘要]
阀门标准 BS EN 558-2008 Industrial valves. Face-to-face and centre-to-face dimensions of metal valves for use in flanged pipe systems.pdf [db:摘要]
