阀门标准 BS 1868-1975(R1990) Steel check valves(flanged and butt-welding ends) for the petroleum,petrochemical and allied industries.pdf [db:摘要]
阀门标准 BS 1212-3-1990 Float operated valves. part 3 Specification for diaphragm type float operated valves (plastics bodied) for coldwater services only.pdf [db:摘要]
