FIELD: oil production, particularly to lift fluid from periodically flowing well under low reservoir pressure.
SUBSTANCE: device comprises double pipe string including inner and outer pipe strings arranged in well. Produced fluid lifting means is installed at lower end of inner pipe string. The produced fluid lifting means is made as two-chamber activator including high-pressure chamber and vacuum one. The activator is arranged on outer pipe string support. Each chamber has orifices in bottom thereof and is provided with ball valve. Contraction-diffuser nozzles are created in side surface of high-pressure chamber so that the nozzles are distributed along helical line and shifted one from another by 360°:2n angle, where n is number of nozzles in one helical line turn. Contraction part of inner chamber wall is of cylindrical shape. Diffuser part thereof is shaped as truncated cone. Cylindrical orifices are made in side surface of vacuum chamber. Working agent is gas.
EFFECT: possibility of gas injection in pipe string, increased cost efficiency and simplified technology, possibility to measure reservoir pressure and temperature at well bottom.
4 cl, 5 dwg
