Applicable standards: 1.Basic design:Api602 & Ansi B16.34 2. Flanged end (F.E):Ansi B16.5 3. Face to face:Ansi B16.10 4.Valves test and inspect:Api598 5.Standard material:A105.LF2.F5.F11.F22.F304.F304L.F316.F316L Features: 1.Bolted bonnet or welded bonnet 2.Spiral wound gasket of stainless steel 3.Flanged ends pact outside screw & yoke 5.Replaceable hardfaced seats 6.Size:1/2"-2 1/2"