GEAR TO RAISE FLUID FROM WELL BY PUMP Russian patent published in 2004 - IPC

FIELD: running of oil wells. SUBSTANCE: invention is meant for forced lift of fluid when it does not go up due to lack of reservoir energy or formation pressure. Gear includes string of pipes and system "cylinder-piston" mounted on lower end of string and activated by mechanical drive from rocker. Cylinder is made fast to string of lifting pipes. Check valve separating space of string and space of cylinder is placed between string of lifting pipes and cylinder. Piston has orifice shut off by check valve from above and is hydraulically coupled to substitution chamber. The latter comes in the form of closed reservoir with side windows shut off from inside or outside with filter and hydraulically communicating space of chamber with space of well. Substitution chamber is anchored with lower part in well. Volume of substitution chamber is greater or equal to volume of cylinder. EFFECT: widened application field. 2 cl, 3 dwg