电动球阀前后双重密封结构设计 THE bi-sealing design structure,i seat in front of the ball and seat sealing behind the ball
对于某些特定的工况要求以及用户要求，固定球阀可以采用球前球后双重密封结构设计，即是其中一个密封副因意外情况密封失效，阀门仍然能够正常工作，从而提高了阀门的密封可靠性，
对于球前阀座，有D1，D2的面积差形成的活塞效应，在阀前后的介质压差作用下，加上弹簧的预紧力使球阀前阀座与球体紧密接触而密封，并且密封力随着介质压差的增大而增加。
e乐彩对于球后阀座，有D2，D3的面积差形成的活塞效应，在阀座前后的介质压差作用下，加上弹簧的预紧力使球后阀座与球体紧密接触而密封，并且密封力随着介质压差的增大而曾加。

According to some special working conditions and customers, requirement ,MINGTAI has provided the trunnion ball valve with the BI sealing design structure ,seat sealing in front of the ball and seat sealing behind the ball ,thus the reliable sealing of the valve is ensured because the valve can perform normally even if one of the effective sealing designs becomes lost due to the abnor malcondition