摘要 |
A tubular wellhead member has an inner seal surface. A hydraulic passage extends through the wellhead member and terminates at a port at the seal surface. A tubing hanger having an outer mating surface lands in the wellhead member. A hydraulic line extends from a hydraulically operated downhole safety valve to a passage in the tubing hanger and terminates at a tubing hanger port. A seal is located at the tubing hanger port for sealing the junction with the tubular member port. A check valve is located within the seal to maintain the tubing hanger fluid passage closed until the tubing hanger lands in the wellhead. An adapter is employed to apply a running-in hydraulic fluid pressure to the tubing hanger hydraulic fluid passage with the check valve open. Then, the adapter closes the check valve to trap hydraulic fluid pressure in the line leading to the downhole safety valve. This pressure is sufficient to maintain the downhole safety valve in an open position during running in.
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