Hydraulic actuation of double lift pumps arranged round well to serve as extraction pump for use in onshore and offshore petroleum production

摘要

The drive unit has a pump (301,302) constantly delivering to a pressure vessel (303), which provides pressure to actuate different pumps through a multi-way solenoid valve (306). An energy recovery unit, a regulator of ascent and descent speed of independent actuating cylinders and regulation of the time fluid is injected combine to adjust the stroke of the pistons.