DOWNHOLE ELECTRIC DRIVEN PUMP UNIT

摘要

The invention relates to a downhole electric driven pump unit for oil production. Said unit comprises a submersible electric motor (1), a driven oil pump (2), a working plunger pump (4), an oil tank (7) provided with a secondary oil filter (8), an oil volume expansion compensator (9) and a hydraulic engine (10). The above-piston and under-piston cavities (11, 12) of the hydraulic engine cylinder (13) are connected to the oil pump suction and discharge sides (15, 16) through a distributor (14).The hydraulic engine piston (17) is connected to the plunger (18) of the working pump. The electric motor is provided with a protector (19) and is cinematically linked with the driven pump shaft by means of the protector shaft. The working pump cylinder (20) is provided with a sealed cylindrical diaphragm (21) made of elastic material in such a way that a cavity (22) filled with oil is formed. The working pump plunger (18) is mounted in such a way that it is reciprocatingly displaceable in the cavity (22). A pressure valve (31) is arranged above the discharge valve (6) in such a way that a cavity (23) is formed. The compensator (6) is embodied in the form of a cylinder (24) provided with a cylindrical diaphragm (25) which is placed therein in such a way that an internal sealed cavity (26) communicating with the oil tank (7) and an annular cavity (27) is formed. Said invention makes it possible to increase the performance factor and reliability of the unit.