Patent attributes
A valve includes a valve body, a valve element to selectively control flow through the valve, and a seal member and seat member together providing a fluid-tight seal between a valve cavity and a fluid passage in the valve body. A live-loaded biasing member is adapted to apply a live-loaded sealing force to the seat member to bias the seat member toward sealing engagement with the valve element. When the pressure in the fluid passage exceeds the pressure in the valve cavity, an unbalanced passage pressure load biases the seat member toward sealing engagement with the valve element. When the pressure in the valve cavity exceeds the pressure in the fluid passage, an unbalanced cavity pressure load biases the seat member toward sealing engagement with the valve element. The live-loaded sealing force is in parallel with each of the unbalanced passage pressure load and the unbalanced cavity pressure load.
