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Well-safety-valve

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Well safety valve

Details

Inventors: Calhoun, Michael B.; Holland, Jr., Robert L.; Scott, Paul D.;
Assignee: Otis Engineering Corporation (Dallas, TX)
Primary Examiner: Novosad; Stephen J.
Assistant Examiner:
Attorney, Agent or Firm: Garland; H. Mathews

A wire line removable well safety valve in an oil and gas well completion design including a tubing string, a well packer around the tubing string sealing with the well casing, and a submergible well pump on the tubing string below the packer. The safety valve controls flow of pumped well fluids through the tubing string, directs separated gas into the casing annulus around the tubing string above the packer, and shuts off the flow of pumped fluids and separated gas to the surface while permitting recirculation of pumped well fluids between the annulus and tubing string below the packer. The safety valve includes a housing having separate central and annular flow passages for pumped fluids and separated gas, respectively, a ball valve for controlling flow of pumped fluids in the central flow passage, an annular bypass valve for controlling flow of separated gas along the annular flow passage, and a recirculating valve between the central and annular flow passages for recirculation of pumped fluids when the ball and bypass valves are closed. The safety valve is held open hydraulically from the surface and includes means for closing the valve when hydraulic pressure fails, shutting off the flow of pumped fluids and bypass gas while permitting continuous operation of the well pump by recirculating pumped fluids below the packer.

DETAILED DESCRIPTION What is claimed is: 1.
A well safety valve comprising: a longitudinal valve housing; means in said housing defining a longitudinal central flow passage and a separate longitudinal annular flow passage; valve means in said central flow passage; valve means in said annular flow passage; recirculating valve means between said central and said annular flow passage; and means coupled with said valves for simultaneously opening said recirculating valve and closed both said central and said annular flow passage valves and for simultaneously closed said recirculating valve and opening both said central and said annular flow passage valves.
2.
A well safety valve in accordance with claim 1 wherein each of said valve means is remotely controllable.
3.
A well safety valve in accordance with claim 2 wherein said valve means are operable responsive to hydraulic fluid pressure.
4.
A well safety valve in accordance with claim 3 wherein said valve means in said central flow passage is a ball valve and said valve means in said annular flow passage and said recirculating valve means are longitudinally spaced each from the other and from said ball valve and comprise an annular valve member and an annular valve seat.
5.
A well safety valve in accordance with claim 4 wherein said ball valve is connected with and operates each of said annular valves by a central control tube defining said central flow passage through said valve housing.
6.
A well safety valve in accordance with claim 5 wherein said valve housing is connectible with a wireline operable locking mandrel.
7.
A well safety valve in accordance with claim 6 including longitudinally spaced annular seals on said housing for sealing around said housing with the inner wall of the tubing string and means defining a side port in said housing between said seals leading to said annular flow passage up stream from said annular valve in said annular flow passage, said recirculating valve is up stream of said annular valve in said annular flow passage, and a side port between said recirculating valve and said annular valve in said annular flow passage leading into said annular flow passage

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