Patent ID: 7201362

Claim:
A thruster valve for controlling a flow of a high temperature fluid, said thruster valve comprising: a valve casing having a fluid flow passage in which a valve plug is disposed, and a through hole; a graphite liner arranged in said through hole, said graphite liner having a cavity and drive rod through holes; a drive rod slidably received in said drive rod through holes of said graphite liner such that a seal is formed and maintained between said drive rod and said graphite liner, said drive rod having an interior end arranged inside said valve casing and an exterior end arranged outside said valve casing, wherein said drive rod is arranged so as to be driven in an axial direction by an actuator attached to the exterior end of said drive rod, and wherein the interior end of said drive rod is attached to the valve plug; and at least one relief hole formed so as to extend through said graphite liner and said valve casing in a direction transverse to the axial direction of said drive rod so as to communicate said cavity of said graphite liner with the exterior of said valve casing, such that any high temperature fluid leaked from said fluid flow passage into said cavity of said graphite liner is provided a drain passage from said cavity to the exterior of said valve casing.