Ballvalve having easy maintenance features for extreme environments

摘要

A valve assembly is provided which is particularly suitable for operation and maintenance under extreme environments. It includes a valve body, a ball valve member rotatably mounted within the valve body, a bonnet removably secured to the valve body, and seat retaining asemblies removably secured to the bonnet. Upon removal of the bonnet, the valve member and all internals are also removed as a unit so that they may be serviced at a convenient location. The seat retaining assemblies may include inclined surfaces which seat against oppositely inclined surfaces defined within the valve body. An alignment plate is secured to the seat retaining assemblies to insure proper sealing.