초록

A gate valve assembly, the assembly includes a gate valve having a gate assembly moveable between a closed position and an open position. The gate assembly includes a pressure equalizing assembly coupled to the gate valve that equalizes the fluid pressure across the gate valve.

대표청구항 ▼

1. A gate valve assembly, comprising: a gate assembly configured to move between an open position and a closed position to open and close a passage in a gate valve body, the gate assembly comprising: a first gate;a second gate; anda first pressure equalizing assembly between the first gate and the s

1. A gate valve assembly, comprising: a gate assembly configured to move between an open position and a closed position to open and close a passage in a gate valve body, the gate assembly comprising: a first gate;a second gate; anda first pressure equalizing assembly between the first gate and the second gate, wherein the first pressure equalizing assembly is configured to equalize a fluid pressure in the gate valve body between upstream and downstream sides of the gate assembly, the first pressure equalizing assembly comprises: a housing, wherein the housing defines a first port configured to intake or discharge a fluid relative to the housing and a second port configured to intake or discharge the fluid relative to the housing;a flow control assembly disposed within the housing between the first and second ports, wherein the housing is configured to route the fluid entering the housing through the flow control assembly, the flow control assembly comprises: a cage that defines a plurality of apertures, wherein the cage is configured to route the fluid through one or more of the plurality of apertures between the first port and the second port; anda closure assembly, wherein the closure assembly comprises a closure member configured to open and close the plurality of apertures in the cage, wherein the closure member is configured to move a first distance independently of the first gate and the second gate to equalize the fluid pressure in the gate valve body between the upstream and downstream sides of the gate assembly. 2. The gate valve assembly according to claim 1, wherein the first gate is a first floating gate and the second gate is a second floating gate. 3. The gate valve assembly according to claim 1, wherein the first pressure equalizing assembly is configured to direct all the fluid entering the housing through the first or second ports to flow through the flow control assembly. 4. The gate valve assembly according to claim 1, wherein the first port is in fluid flow connection with the outside of the cage. 5. The gate valve assembly according to claim 4, wherein the second port is in fluid flow connection with an interior of the cage. 6. The gate valve assembly according to claim 1, wherein the housing comprises a cavity therein connected to the first port, the flow control assembly being disposed within the cavity. 7. The gate valve assembly according to claim 6, wherein the flow control assembly is arranged centrally within the cavity, such that the cavity extends around the flow control assembly. 8. The gate valve assembly according to claim 6, wherein the first port is arranged in the housing to extend tangentially to a wall of the cavity. 9. The gate valve assembly according to claim 1, wherein the cage is a generally cylindrical tube, with the plurality of apertures extending through a wall of the generally cylindrical tube. 10. The gate valve assembly according to claim 1, wherein the apertures are arranged in the cage in a plurality of rows, each row containing one or more apertures, with adjacent rows being separated by a land or region having no apertures therethrough. 11. The gate valve assembly according to claim 10, wherein a center of each of the plurality of the apertures in adjacent rows of the cage are offset from each other circumferentially around an exterior surface of the cage. 12. The gate valve assembly according to claim 11, wherein the apertures are arranged such that adjacent apertures in adjacent rows extend in a helical pattern along and around the cage. 13. The gate valve assembly according to claim 1, wherein the apertures extend inwards, in a plane perpendicular to a longitudinal axis of the cage at an angle to a radial direction. 14. The gate valve assembly according to claim 13, wherein the apertures extend through a wall of the cage and open tangentially to an inner surface of the wall of the cage. 15. The gate valve assembly according to claim 1, wherein the apertures extend through a wall of the cage at an angle to a plane perpendicular to a longitudinal axis of the cage and at an angle to a radial direction. 16. The gate valve assembly according to claim 15, wherein the apertures extend at an angle to the plane perpendicular to the longitudinal axis in either an upstream direction or downstream direction of fluid within the cage. 17. The gate valve assembly according to claim 16, wherein the apertures are angled to avoid a fluid stream from one aperture contacting the fluid stream from an adjacent aperture. 18. The gate valve assembly according to claim 1, wherein the closure member is disposed within the cage or outside of the cage, and the closure member is moveable with respect to the cage and the apertures extending through a wall of the cage. 19. The gate valve assembly according to claim 1, wherein the first pressure equalizing assembly comprises a first closure member disposed within the cage and a second closure member disposed outside the cage. 20. The gate valve assembly according to claim 19, wherein the first and second closure members are moveable together. 21. The gate valve assembly according to claim 20, wherein the first and second closure members are sized and arranged differently with respect to one another and the cage, such that in a given position of the closure assembly, the first and second closure members are obscuring and closing a different number of apertures. 22. The gate valve assembly according to claim 1, wherein the closure assembly of the first pressure equalizing assembly is arranged so as to be balanced with respect to the fluid pressure within the first pressure equalizing assembly. 23. The gate valve assembly according to claim 22, wherein the closure assembly is balanced with respect to both fluid pressure at the first port and fluid pressure at the second port. 24. The gate valve assembly according to claim 1, comprising a second pressure equalizing assembly, wherein the first and second pressure equalizing assemblies are actuated by a single actuator. 25. A gate valve assembly, comprising: a gate assembly configured to move between an open position and a closed position to open and close a passage in a gate valve body, the gate assembly comprising: a first gate;a second gate; anda pressure equalizing assembly between the first gate and the second gate, wherein the first pressure equalizing assembly is configured to equalize a fluid pressure in the gate valve body between upstream and downstream sides of the gate assembly.