US Patent 7484710 Fluid flow control valve with high temperature bi-directional shutoff

A control valve of the ball type with bi-directional shutoff capabilities is disclosed. The ball valve including an inlet and an outlet, a ball element and a seal assembly. When closing the valve, the ball element, which is eccentrically mounted on a shaft, rotates to abut the seal assembly. While closed, the seal assembly including a seal housing, a main seal and a resilient member, contacts the ball element at the main seal, while the resilient member biases the main seal toward the ball element. The seal assembly further includes a secondary flowpath between the main seal and seal housing, which is restricted by a high temperature seal.