... clamp, welding neck flangeStructure formFloat, fixed, V-type, and eccentric rotatingSeal formSoft seal, hard, and PTFE sealedConstruction materialA105, SS304, ... working conditions and allowable leakage for soft seal type O ball valve, type V ball valve and eccentric rotating ball ... working conditions and allowable leakage for hard seal type O ball valve, type V ball valve and eccentric rotating ball ...