Abstract: A method of sealing a valve engaging member to a valve body about a borehole and structure thereof. Two seal members disposed on either side of the valve engaging member include a seat member adjacent the valve engaging member and a pocket insert adjacent the seat member. The pocket inserts fit within first and second pockets of the valve body. A C-shaped seal ring is disposed between the seat member and pocket insert, and two U-shaped seal rings are disposed between the pocket insert and the valve body. One of the U-shaped seal rings between the pocket insert and the valve body functions both as a radial seal ring and a retaining ring.

Abstract: A hydraulic actuator (20) with a built-in hydrostatic pressure compensator (111) is provided. The actuator (20) includes an actuator housing (30), a compensator cylinder portion (86), a compensator piston portion (94), a first compensator piston chamber (98), a second compensator piston chamber (103), a hydraulic port (106), and a hydraulic via (108). The compensator cylinder portion (86) is located within the actuator housing (30), is fixed relative to the housing (30), and has a compensator cylinder internal chamber (88) formed therein. The compensator piston portion (94) slidably fits within the compensator cylinder internal chamber (88). The first compensator piston chamber (98) is formed between a first side (101) of the compensator piston portion (94) and the compensator cylinder portion (86). The second compensator piston chamber (103) is formed between a second side (102) of the compensator piston portion (94) and the compensator cylinder portion (86).

Abstract: Valve sealing assemblies and methods of sealing a valve engaging member to a valve body. A first seat member is fixedly disposed within a valve body pocket. Two seal rings are disposed between a valve pocket and a pocket insert and a seal ring is disposed between the pocket insert and a seat member to provide a downstream seal. A built-in lip on one of the seat members and an accommodating groove on the other seat member prevent debris from entering the space between the two seat members. A retainer ring on the exterior annular surface of pocket insert seat member retains the pocket insert within valve body. A retainer ring on the exterior annular surface of the seat member retains the seat member within the pocket insert.

Abstract: A modular portion (71) of a hydraulic valve actuator (64) comprises a hollow cylinder portion (74), a piston (78), a cylinder head portion (80), and a piston retainer portion (88). The piston (78) is located in the cylinder portion (74), and the piston (78) is adapted to slidably fit in the cylinder portion (74). The cylinder head portion (80) closes a second end (110) of the cylinder portion (74). The piston retainer portion (88) is located at an interior surface (134) of the cylinder portion (74) and at a first end (106) of the cylinder portion (74). Part of the piston retainer portion (88) extends radially inward relative to the interior surface (134) of the cylinder portion (74) farther than a portion of the piston (78) such that the piston (78) cannot slide completely past the piston retainer portion (88).

Abstract: A hydraulic actuator for operating a gate valve. The actuator includes a stationary piston coupled to an actuator housing and a moveable cylinder disposed proximate the piston exterior surface. The piston includes a hollow interior portion adapted to house a manual override mechanism. The piston includes a hydraulic pressure line extending between the piston bottom surface and the side of a cap region in the piston. The manual override mechanism includes an override stem disposed within the piston interior portion, the override stem abutting the cylinder.