DEVICE FOR OIL RECOVERY AND TREATMENT OF BOTTOMHOLE ZONE Russian patent published in 2003 - IPC

FIELD: oil producing industry; applicable in oil recovery with concurrent treatment of bottomhole zone. SUBSTANCE: device has cylindrical body plugged in its lower end, plunger, plunger stop and filter. Cylindrical body has connecting and extending members on its ends and intake holes in its upper part. Plunger is installed in body for reciprocation and has upper and lower pressure control valves with seats. Length of plunger is not less than its stroke length. Plunger stop determines its lower nonworking position. Filter is installed on cylindrical body connecting member and located at level of intake holes. One of pressure control valves is located under seat and is communicated with sucker-rod string for reciprocation within valve working stroke. Plunger stop is located so that plunger in lower nonworking position proves to be below level of intake holes of cylindrical body. Cylindrical body is provided with settler, in its lower end part. EFFECT: higher pump capacity without increase of immersion to under dynamic level, eliminated shortcomings in operation of series-produced valves occurring in repair of operating wells, increased pump capacity in directional wells. 2 dwg