Three Piece Forged Trunnion Mounted Ball Valve - A & L Valve ...

ISV Series BT3E & BT3G and ISV by MSA 3 Piece Construction Forged Trunnion Mounted BallDESIGN DETAILSSeat: Polymeric or elastomeric seat designSpring loaded seats ensure tight seal at low differential pressure bypushing the seat towards the ball. The unique seat design controlsthe amount of seat force against the ball to achieve a tight seat seal atoptimum valve operating torque.Metal seat ring with elastomeric insert is used for reliable bubble-tightgas service applications. The elastomeric seat inserts are delta shapedand normally provided as HNBR, Viton or as requested.Metal seats with elastomeric delta seat inserts have Double PistonEffect feature (DPE). DPE or “double isolation” feature enables thedownstream side seat seal to remain tight if the upstream seat isdamaged.Polymeric seat insert designs including PTFE, Nylon, PEEK are the preferredseat design option for liquid services & class 900 and higherapplications.Position adjustment (Bare Stem):Bare stem valves are equipped with a unique ball open and close positioning deviceat the stem. This feature enables precise ball positioning when installing orremoving actuators on ISV by MSA ball valves even while the valve is installed inthe pipeline.Test roomBall MachinePhotos at MSA6