DRIVE OF WELL PUMPING UNIT Russian patent published in 1999 - IPC

FIELD: driving two deep well sucker-rod pumps. SUBSTANCE: air-loaded hydraulic accumulator 17 is made in form of tandem cylinder with rod 19 having pins 20 and 21 secured at its ends and two hydraulic chambers 22 and 23; each chamber is connected with rod ends of drive cylinders 1 and 2. pressure of working fluid in chambers 22 and 23 and in chambers 3 and (3′) may be equal (at equilibrium of both wells) and different (when equilibrium is disturbed) due to creation of pressure in chamber 28 of air-loaded hydraulic accumulator 17, thus making it possible to operate well pumps at balanced load, at disturbed balance and during operation of one pump. EFFECT: enhanced reliability. 1 dwg