ADJUSTABLE POSITIVE-DISPLACEMENT INFLATOR PUMP UNIT Russian patent published in 2010 - IPC F04B9/08 

FIELD: engines and pumps.

SUBSTANCE: proposed unit serves to force fluid into formation to maintain formation pressure in development of oil and gas accumulations. Pump unit comprises two working hydraulic cylinders with intake and discharge valves, two drive hydraulic cylinders with pistons rigidly coupled with con rods, and adjustable hydraulic pump with hydraulic lines. Said pump is arranged in the casing. The device comprises also check valves, safety calve, working fluid tank, primary power source coupled with hydraulic pump input shaft and control unit. Casings of working and drive hydraulic cylinders are spaced apart for piston travel and rigidly jointed together by metal clips or similar appliances to make two hydraulic units. The latter are mounted successively in vertical direction and attached to the base common post. Chambers of working hydraulic cylinders are graduated. Pistons represent plungers pivoted to drive cylinder piston con rods. Piston underside chambers of drive hydraulic cylinders communicate, via hydraulic line, with two cocks. Said hydraulic line communicates in its turn, via extra line with cock, with one of adjustable hydraulic station hydraulic lines. Plunger diametre-to-travel ratio is selected from the following relationship, i.e. where K is the factor describing aforesaid ratio, ⌀_pl is the plunger diametre, mm, and L_pl is the plunger length, mm.

EFFECT: simplified design, longer life.

5 dwg