... T 12221-19895) Pressure test: GB/T 13927-1992; JB/T9092-1999Material for main partsBody: Cast iron, stainless steel, ... , stainless steel, Cr .Mo .SteelSeal ring: Stainless steel, multi-layer asbestos with temperature resistantStem: Stainless steel, Cr .Mo .SteelBearing ... dimensional principle, the compatible to soft sealing and metal multi-layer structure, with best machining and advanced technology. ...