Cast Iron Gate Valve Main parts and materials Parts Name Materials Bodyã??Bonnet Cast iron ASTM A126 CL. B Disc Cast iron ASTM A126 CL. B+Bronze B16/Stainless Steel 2Cr13 Stem Brass B16/Stainless Steel 2Cr13 Seat Ring Bronze B62/Brass B16/Stainless Steel 2Cr13 Standards Design and Manufacture Face to Face Flange End MSS SP-70 ANSI B16.10 ANSI B16.1 Test Nominal Pressure (PSI) Shell Test (PSI) Seal Test (PSI) 125 350 200