Abstract: A gate valve comprises a valve body, a stem bore which extends through the valve body, a stem which is disposed in the stem bore and which includes a first stem portion that is sealed to the stem bore, a second, smaller diameter stem portion that is sealed to the stem bore, and a gate pocket that is located between the first and second stem portions, and gate which is disposed within the gate pocket between the first and second seats.

Abstract: The present invention is directed to a valve for controlling the flow of fluid through a component which includes a flow conduit extending therethrough. The valve comprises a first closure member for controlling the flow of fluid through the conduit, a second closure member for controlling the flow of fluid through the conduit, and a valve stem which is connected to both the first and second closure members. The stem is responsive to an external force to move the first and second closure members from a closed position, in which the fluid is blocked from flowing through the conduit by both the first and second closure members, to an open position, in which the fluid is permitted to flow through the conduit past both the first and second closure members.

Abstract: A gate valve comprises a valve body which includes a stem bore that extends therethrough and a seat bore that extends therethrough and intersects the stem bore generally transversely. A stem is disposed in the stem bore and includes a first stem portion that is sealed to the stem bore, a second stem portion that is sealed to the stem bore, and a gate pocket that is located between the first and second stem portions. First and second seats are each positioned at least partially within the seat bore proximate the gate pocket and each include a flow bore that extends therethrough. The gate valve also includes a gate which is disposed within the gate pocket between the first and second seats, a first actuator for moving the gate from a first position to a second position, and a second actuator for moving the gate from the second position to the first position.

Abstract: A gate valve is disclosed which comprises a valve body having an internal flow passage which extends between an inlet port and an outlet port, a pair of seats mounted in respective seat pockets formed in the body coaxial with the flow passage, a gate disposed between the seats and having a transverse opening therethrough, and a valve stem threadedly connected to the gate, wherein rotation of the valve stem raises or lowers the gate to bring the opening into or out of alignment with the flow passage to either open or close the gate valve, respectively. Each seat comprises a generally cylindrical body portion having a substantially uniform outer diameter surface and first and second end faces which are adapted to seal with the gate. In this manner, each seat may be mounted in its seat pocket with either the first end face or the second end face adjacent the gate.

Abstract: The present invention is directed to a gate valve which in one embodiment comprises a valve body having an internal flow passage which extends between an inlet port and an outlet port; a pair of seats mounted in respective seat pockets formed in the body coaxial with the flow passage; a gate disposed between the seats and having a transverse opening therethrough; and a valve stem threadedly connected to the gate; wherein rotation of the valve stem raises or lowers the gate to bring the opening into or out of alignment with the flow passage to either open or close the gate valve, respectively; and wherein each seat comprises a generally cylindrical body portion having a substantially uniform outer diameter and first and second end faces which are adapted to seal with the gate; whereby each seat may be mounted in its seat pocket with either the first face or the second face adjacent the gate.

Abstract: The present invention is directed to a valve for controlling the flow of fluid through a component which includes a flow conduit extending therethrough. The valve comprises a first closure member for controlling the flow of fluid through the conduit, a second closure member for controlling the flow of fluid through the conduit, and a valve stem which is connected to both the first and second closure members. The stem is responsive to an external force to move the first and second closure members from a closed position, in which the fluid is blocked from flowing through the conduit by both the first and second closure members, to an open position, in which the fluid is permitted to flow through the conduit past both the first and second closure members.

Abstract: A caisson gate valve (10) fitting within an outer casing (12) extending downwardly from a subsea wellhead below the sea floor is disclosed. The gate valve (10) includes a valve body or block (14) having an axial bore or flow passage (16) therethrough and a transverse cavity (18) in body (14) which extends through the body (14) to provide open ends (19) for cavity (18). Covers (60, 66) are mounted over the open ends (19) of cavity (18). A gate carrier (24) has an oval opening (26) which receives a gate member (28) having a gate opening (30) therein for movement between open and closed positions relative to the flow passage (16). A pair of opposed stems or pistons (32, 34) extend from gate carrier (28) for actuation of gate carrier (24) and valve member (28) between open and closed positions relative to flow passage (16). Fluid chambers (36, 38) adjacent pistons (32, 34) provide pressurized fluid for actuation of gate carrier (24) and gate member (28) therein.

Abstract: A gate valve adapted for stem back seating has a stem and bonnet assembly with a rotatable bearing ring to which the stem is releasably fixed during normal gate opening and closing operations. During back seating, the stem is released from the bearing ring and the bearing ring is fixed to the bonnet cap, enabling low torque back seating by rotation of the stem relative to the bearing ring and bonnet cap.

Abstract: A kelly cock valve for a drill rig uses a sliding gate to open and close the flow passage through the drill string. The valve has a body with a longitudinal passage through it. The gate is mounted in the body perpendicular to the flow passage. Pushrods extend from each end of the gate out through bonnets mounted to the body of the valve. The fluid cylinders are mounted on each side of the gate. Each fluid cylinder has a piston with a piston rod extending in opposite directions. The piston rods are connected to a beam that also connects to the pushrod. Hydraulic passages supply fluid to the cylinders to stroke the piston and thus move the gate valve between open and closed positions.

Abstract: A gate valve having a body with a valve chamber therein, an inlet passage through the body into the valve chamber, an outlet passage through the body into the valve chamber, a gate positioned within the chamber and having an opening therethrough, a body sealing surface surrounding the openings of each of the inlet and outlet passages within the passages within the chamber, a seat ring positioned between the gate and each of the body sealing surfaces, means for urging the seat rings against their body sealing surfaces, resilient seals between each seat ring and its body sealing surface near the inner and outer diameter of each ring, means for sealing between the gate and the seal rings, and means for moving said gate in said chamber to close and open flow through said valve.