ASME B16.24-1991 铸铁管道法兰和带法兰管件 Cast Copper Alloy Pipe Flanges and Flanged Fittings Class 150 3004006009001500 and 2500..pdf 未知 JIS B2031-1994 Gray cast iron valves.pdf 未知 BS EN 1092-2-1997 Flanges and their joints. Circular flanges for pipes valves fittings and accessories PN designated. Cast iron flanges.pdf 未知 JIS B 2031-2013 灰口铸铁阀 Gray cast iron valves.pdf 未知