WELL PUMP UNIT Russian patent published in 2018 - IPC E21B43/00 F04D13/10 E21B34/06 

FIELD: oil and gas industry.

SUBSTANCE: submersible centrifugal pump with electric motor is installed in the well on a tubing string. A compensator is installed above them. A pneumatic cap with piston is placed therein. From the inside, the piston is spring-loaded by pack series-connected plate springs separated by gaskets. The gaskets form a clearance with pneumatic cap inner surface. The plate springs are configured with different ratios of spring cone height to cone wall thickness and have such power characteristic, so that at parallel connection of forces of spring stack and pressure inert gas on the piston, a resultant restoring force is created with working portion of given low quasi-zero rigidity.

EFFECT: increased serviceability and reliability of plant operation, reduced vibration of underground pump equipment caused by presence of gas inclusions in pumped out product.

8 dwg