... of corrosion, such as acid gas.Structure Characteristics1,fully welded construction2,design according to API 6D3,floating mounted and self- ... type, low torque5,single piston design with self-relieving seat and double piston design is available6,stem estension is available7 ... insert : PTFE,NYLON,PEEK,VITON Applicable standard for Valve :Design and Manufacture according to: API6D,ASME B16.34Length of ...