... gage 4)Surface Polishment and NDT Test 5)ISO9001:2 Gate Valve StemsStandard: ASTM, BF,BS, JIS, UNI, ANSI ... , Grey Iron, Copper, Aluminum Bronze, Malleable Iron etc.2) Process: Investment Casting, Sand Casting (Resin Sand Casting ... JIS, UNI, ANSI, ISO etc.valve stem of 303 stainless steel4"API Gate ValveMaterial: Alloy Steel, Stainless SteelMachined ... before packing. JIS API lengthening Gate Valve Stem