Wireline Retrievable Subsurface Safety Valve
After installation of the completion string, we can run, locate & lock a wireline retrievable subsurface safety valve WRSV into a safety valve landing nipple (SVLN) before production. The SVLN (valve nipple) is integral to the tubing string. The valves typically open due to the hydraulic pressure acting on a piston which moves a flow tube against the ball or through the flapper. On bleeding off pressure, a spring ensures reverse movement of the piston and the flow tube, allowing valve closure.
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