DEEP-WELL PUMP Russian patent published in 2018 - IPC F04B47/08 

FIELD: engines and pumps.

SUBSTANCE: invention relates to pumping equipment and can be used in oil producing industry at operation of marginal wells. Pump contains submersible motor with hydroprotection. Drive unit of normal pump converts rotational motion into reciprocating motion. Normal pump consists of a body, inlet, raveling and bypass valves, slave cylinder, hollow multistage plunger piston, lower stage of which is connected to stem dipping and has diametrical size smaller than diametrical size of upper stage. Under slave cylinder there is additional cylinder, inside which of hollow multistage plunger piston is located. Slave cylinder does not have rigid fixing inside the body.

EFFECT: absence of rigid fixing of slave cylinder allows it to self-center with respect to hollow multistage plunger piston, which eliminates its jamming and improves reliability of a pump and its working lifespan.

1 cl, 1 dwg