OIL-WELL SUCKER-ROD PUMPING UNIT (VERSIONS) Russian patent published in 2015 - IPC F04B47/02 

FIELD: oil and gas industry.

SUBSTANCE: oil-well sucker-rod pump unit consists of long immobile flexible tube with long flexible mobile rod inserted inside, with one rod end connected to power drive on the surface and the other rod end connected to end effector of submersion plunger or screw pump. Inlet and outlet points of long mobile flexible rod and long immobile flexible tube are sealed. Annular space between them is filled with liquid lubricant and features a channel at the wellhead end. Bottom and top ends of immobile flexible tube are connected to wellhead and pump taps. At the bottom rod end, a shell filled with a high-gravity liquid ensuring protection of plunger pump seal is positioned. Long flexible rod is capable of rotational or reciprocal movement. In another version, an overturned shell filled with liquid lubricant ensuring protection of well pump seal is positioned at the bottom rod end and is fed from a bypass valve calibrated for design pressure and installed between the shell and the annular space. Separate lift string or multichannel coil tubing can be used for well fluid transportation to the surface.

EFFECT: improved reliability of deep-well pump operation, longer period between overhauls, reduced power cost of pump operation.

6 cl, 6 dwg