This Standard covers cast copper alloy threaded-joint pipe flanges and blind pipe flanges having rating class designations 150, 300, 600, 900, 1500, and 2500. This standard also covers flanged fittings having rating class designations 150 and 300. It establishes requirements for: (a) pressure-temperature ratings; (b) sizes and methods of designating openings for reduced fittings; (c) markings; (d) materials; (e) dimensions; (f) bolting and gaskets; (g) tolerances; and (h) tests. This standard also provides dimensional requirements for flanged ends of valves conforming to MSS SP-80.