| 摘要 |
A system for lifting liquid from a wellbore includes a turbine selectively coupled to a source of gas flow originating in the wellbore. The turbine is arranged to convert the gas flow directly into rotation of the turbine. An hydraulic pump is rotationally coupled to the turbine. An hydraulic cylinder and piston are arranged to move a sucker rod string disposed in the wellbore. Control valves are provided to selectively apply gas flow to the turbine and hydraulic pressure from the pump to lift the piston and enable lowering thereof by the weight of the sucker rod string. The system further comprises control circuits configured to operate the control valves.
|
