| 摘要 |
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.
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