check valve.swing type,flange type. Sizes:DN50~DN600. check valve,swing type,flange type.Design & manufacture standard: API6D, ... .0MPa or JIS 10K, 20K.Nominal diameters: 2~ 24or DN50~DN600.Major materials: WCB, WC1, WC6, WC9, A105, CF8(304), CF8M ...