초록 ▼

A subsurface safety valve has a closure sleeve or rod mounted below the closure mechanism. Control signal pushes the sleeve up (uphole) or down (downhole), whichever is applicable, which causes the closure element to rotate (or slide, or otherwise translate) to its open position. A loss of control s

A subsurface safety valve has a closure sleeve or rod mounted below the closure mechanism. Control signal pushes the sleeve up (uphole) or down (downhole), whichever is applicable, which causes the closure element to rotate (or slide, or otherwise translate) to its open position. A loss of control signal allows the closure spring to push the sleeve or rod downhole (or uphole, whichever is appropriate). This movement causes the closure element to be driven to its closed position against the seat.

대표청구항 ▼

1. A downhole safety valve for a tubular string operated by at least one control line extending independently of the tubular string to the safety valve, comprising:a housing having uphole and downhole ends and a bore extending therethrough and a connection for a control line; a closure element mount

1. A downhole safety valve for a tubular string operated by at least one control line extending independently of the tubular string to the safety valve, comprising:a housing having uphole and downhole ends and a bore extending therethrough and a connection for a control line; a closure element mounted to said housing in said bore; an actuator in fluid communication with said connection for a control line to move said closure element to an open position in response to pressure changes from the control line, said connection mounted substantially between said closure element and said downhole end of said housing; and the weight of said actuator provides at least part of the force to urge said closure element to said closed position. 2. The safety valve of claim 1, wherein:said actuator forcibly pivots said closure element selectively in opposed directions. 3. The safety valve of claim 1, wherein:said actuator is connected directly to said closure element. 4. The safety valve of claim 3, wherein:said closure element comprises a binge extending beyond a mounting pin supported by said housing; said actuator is connected to said extending hinge portion beyond said mounting pin. 5. The safety valve of claim 4, wherein:said connection between said actuator and said hinge portion is accomplished by meshing gears. 6. The safety valve of claim 4, wherein:said connection between said actuator and said hinge portion is accomplished by a projection on one engaging a depression in the other. 7. The safety valve of claim 4, wherein:said actuator comprises a rod piston mounted in said housing. 8. The safety valve of claim 4, wherein:said closure element pivots between an open and a closed position; and said actuator is biased to urge said closure element toward said closed position. 9. The safety valve of claim 8, wherein:said actuator defines a variable volume cavity in said body, said cavity having an inlet on the housing to facilitate movement of said actuator against said bias. 10. The safety valve of claim 9, wherein:said actuator forcibly pivots said closure element selectively in opposed directions. 11. The safety valve of claim 10, wherein:the weight of said actuator provides at least part of the force to urge said closure element to said closed position. 12. The safety valve of claim 11, wherein:said connection between said actuator and said hinge portion is accomplished by meshing gears. 13. The safety valve of claim 12, wherein:said actuator comprises a rod piston mounted in said housing. 14. The safety valve of claim 11, wherein:said connection between said actuator and said hinge portion is accomplished by a projection on one engaging a depression in the other. 15. The safety valve of claim 14, wherein:said actuator comprises a rod piston mounted in said housing. 16. The safety valve of claim 1, wherein:said actuator moves toward said downhole end to move said closure element to a closed position. 17.The safety valve of claim 1, wherein:said closure element comprises one of a flapper, a ball and a sliding gate. 18. The safety valve of claim 1, wherein:said actuator and said closure element are urged toward said closed position by a single biasing element. 19. A downhole safety valve for a tubular string, comprising:a housing having uphole and downhole ends and a bore extending therethrough; a closure element mounted to said housing in said bore; and an actuator responsive to input from outside the tubular string to move said closure element to an open position, said actuator mounted substantially between said closure element and said downhole end of said housing; said actuator is connected directly to said closure element; said closure element comprises a hinge extending beyond a mounting pin supported by said housing; said actuator is connected to said extending hinge portion beyond said mounting pin. 20. A downhole safety valve for a tubular string operated by at least one control line extending independently of the tubular string to the safety valve comprising:a housing having uphole and downhole ends and a bore extending therethrough and a connection for a control line; a closure element mounted to said housing in said bore; and an actuator in fluid communication with said connection for a control line to move said closure element to an open position in response to pressure changes from the control line, said actuator mounted substantially between said closure element and said downhole end of said housing; the weight of said actuator provides at least part of the force to urge said closure element to said closed position; said actuator is connected directly to said closure element; said closure element comprises a hinge extending beyond a mounting pin supported by said housing; said actuator is connected to said extending hinge portion beyond said mounting pin; said closure element pivots between an open and a closed position; and said actuator is biased to urge said closure element toward said closed position; said actuator defines a variable volume cavity in said body, said cavity having an inlet on the housing to facilitate movement of said actuator against said bias; said inlet is located between said closure element and said downhole end of said housing. 21. A downhole safety valve for a tubular string operated by at least one control line extending independently of the tubular string to the safety valve, comprising:a housing having uphole and downhole ends and a bore extending therethrough and a connection for a control line; a closure element mounted to said housing in said bore; and an actuator in fluid communication with said connection for a control line to move said closure element to an open position in response to pressure changes from the control line, said actuator mounted substantially between said closure element and said downhole end of said housing; the weight of said actuator provides at least part of the force to urge said closure element to said closed position; said actuator is connected directly to said closure element; said closure element comprises a hinge extending beyond a mounting pin supported by said housing; said actuator is connected to said extending hinge Portion beyond said mounting pin; said closure element pivots between an open and a closed position; and said actuator is biased to urge said closure element toward said closed position; said actuator defines a variable volume cavity in said body, said cavity having an inlet on the housing to facilitate movement of said actuator against said bias; said actuator forcibly pivots said closure element selectively in opposed directions; the weight of said actuator provides at least part of the force to urge said closure element to said closed position; said connection between said actuator and said hinge portion is accomplished by meshing gears; said actuator comprises an annular piston mounted in said housing. 22. A downhole safety valve for a tubular string operated by at least one control line extending independently of the tubular string to the safety valve, comprising:a housing having uphole and downhole ends and a bore extending therethrough and a connection for a control line; a closure element mounted to said housing in said bore; and an actuator in fluid communication with said connection for a control line to move said closure element to an open position in response to pressure changes from the control line, said actuator mounted substantially between said closure element and said downhole end of said housing; the weight of said actuator provides at least part of the force to urge said closure element to said closed position; said actuator is connected directly to said closure element; said closure element comprises a hinge extending beyond a mounting pin supported by said housing; said actuator is connected to said extending hinge portion beyond said mounting pin; said closure element pivots between an open and a closed position; and said actuator is biased to urge said closure element toward said closed position; said actuator defines a variable volume cavity in said body, said cavity having an inlet on the housing to facilitate movement of said actuator against said bias; said actuator forcibly pivots said closure element selectively in opposed directions; the weight of said actuator provides at least part of the force to urge said closure element to said closed position; said connection between said actuator and said hinge portion is accomplished by a projection on one engaging a depression in the other; said actuator comprises an annular piston mounted in said housing. 23. A downhole safety valve, comprising:a housing having uphole and downhole ends; a closure element mounted to said housing; and an actuator to move said closure element, said actuator mounted substantially between said closure element and said downhole end of said housing; said actuator is connected indirectly to said closure element. 24. The safety valve of claim 23, wherein:said actuator moves toward said uphole end to move said closure element to a closed position.