Patent ID: 7726339

Claim:
A seal cartridge for sealing an outer surface of a plug to an inner wall of a cage in a control valve, the seal cartridge comprising: a flexible seal ring disposed in a seal groove, said flexible seal ring including: a first front sealing face adapted for sealing contact with the outer surface of the plug or with the inner wall of the cage, a rear face, at least one upper face disposed downwardly with respect to an up direction from which energizing fluid pressure is in use applied to the flexible seal ring upper face, said upper face being disposed between the first front sealing face and the rear face, at least one lower face, disposed downwardly with respect to said up direction, and a second front sealing face disposed upwardly with respect to said up direction between the downwardly disposed lower face and the first front sealing face; and an upper retaining ring disposed adjacent to the flexible seal ring, said upper retaining ring including: at least one lower face disposed downwardly with respect to said up direction and proximal to the downwardly disposed upper face of the flexible seal ring; wherein said at least one upper face of the flexible seal ring is adapted to flex away from the at least one downwardly disposed lower face of the upper retaining ring, and said lower face of the flexible seal ring is adapted to flex downward upon the application the energizing fluid pressure to the flexible seal ring upper face.