SUBMERSIBLE RODLESS PUMP UNIT Russian patent published in 2020 - IPC F04B47/00 

FIELD: mining.

SUBSTANCE: invention relates to designs of rodless downhole pumping units for extraction of formation fluids in which submersible linear magnetoelectric engines are used as a drive. Submersible well pump unit includes plunger pump, connected to it submersible linear electric motor, tubing string. Above the pump in the tubing string the pneumatic compensator is installed, which housing is connected by a coupling to a through cylindrical channel and a check valve for pumping of inert gas into a gas chamber formed by an inner space between the housing and a rubber diaphragm, fixed with clamps on the pipe, placed inside the housing and connected in the upper part with a transfer coupling. Pipe is made with slot cuts in two mutually perpendicular planes through which at each injection cycle the pumped well fluid enters the working chamber, which is an internal space between the pipe and diaphragm, compressing gas in the gas chamber. Lower part of pipe is fixed in housing by nuts. Seal washer is installed between nuts.

EFFECT: improved operating mode of well pump unit due to use of pneumatic compensators to reduce pressure fluctuations and flow rate along tubing string.

1 cl, 2 dwg