DOWNHOLE DIAPHRAGM OIL EXTRACTION PUMPING UNIT Russian patent published in 2010 - IPC F04B47/08 F04B43/06 

FIELD: engines and pumps.

SUBSTANCE: invention relates to pumps and can be used in positive-displacement pumps to extract oil from wells. Pumping unit comprises downhole motor and pump. The latter comprises housing with head wherein inlet and outlet holes are made for passage of pumped oil to accommodate suction and discharge valves of the pump. Work chamber accommodates plate-type working diaphragm to divide said chamber into sub-diaphragm chamber and above-diaphragm chamber communicated with said pump suction and discharge valves. Pump comprises also plunger drive chamber filled with work fluid and divided into sub-plunger and above-plunger chambers separated by tight baffle. Said baffle has a bore to accommodate plunger to reciprocate therein. Above-plunger chamber of plunger drive chamber communicates with sub-diaphragm chamber of work chamber. Plunger is spring-loaded towards sub-plunger chamber. Pump comprises plunger hydraulic drive consisting of hydraulic rotor positive-displacement pump coupled with motor shaft and spool-type reversing hydraulic distributor. Pump comprises compensating cylindrical diaphragm oriented along housing axis to form beyond-diaphragm chamber communicated, housing wall channel, with hole clearance and sub-diaphragm chamber communicated with rotor positive-displacement pump inlet. Hydraulic distributor inlet is communicated with outlet of aforesaid rotor pump. Pressure line of hydraulic distributor communicates with sub-plunger chamber of plunger drive chamber via pipeline that passes through sub-diaphragm chamber of compensating chamber. Hydraulic distributor outlet communicates with sub-diaphragm chamber of compensating chamber.

EFFECT: higher efficiency, longer life, reduced sizes.

6 cl, 1 dwg