Quoting Standards Design and Manufacture GB12234 Face to face/End to end dimensions to GB12221 Pressure-Temp Rating GB9131 or JB/T74 or HG20604 Flange dimensions to JB/T74～90 or 9113 or HG20592～20635 Inspection and Test to JB/T9092 or GB13927 Material of main parts Valve Bady WCB WC6 Cr5Mo Valve Cover WCB WC6 Cr5Mo Yoke WCB WC6 Cr5Mo Wedge WCB WC6 Cr5Mo Stem 2Cr13 38CrMoA1、25Cr2MoV 38CrMoA1、25Cr2MoV Seat 25 304 304 Seal Reinforced flexible graphite Packing Reinforced flexible graphite Stem Nut ZCuA110Fe3