METHOD FOR FLUSHING A DOWNHOLE SUBMERSIBLE PUMP AND A CHECK VALVE FOR IMPLEMENTING THE METHOD Russian patent published in 2022 - IPC E21B34/06 E21B37/00 

FIELD: oil industry.

SUBSTANCE: invention relates to the oil industry, in particular to technologies and devices for extracting formation products by a downhole pump and cleaning the downhole pump from deposits without lifting to the surface. A method for flushing a downhole submersible pump, which includes supplying flushing fluid to the pump cavity through a check valve installed above the pump outlet in the lift pipes, creating excess pressure sufficient to open a direct flow of liquid through the check valve towards the pump. In this case, before installation from below, the body of the check valve is additionally equipped with an annular cylinder communicated from below with the outside space, and a movable element with a locking element from below, equipped with an annular piston inserted into the annular cylinder with the possibility of moving down - to the working position from the transport when the spring is compressed. When the movable element is jammed in the working position with no possibility of returning to the transport position, an excess pressure is created in the annulus of the lift pipes by means of a spring, which is transferred to the annular cylinder to force the annular piston with the movable element to move upwards to the transport position.

EFFECT: exclusion of aggressive action on the spring by isolating it from the internal space of the valve, exclusion of a pulsating effect when flushing the pump due to the fixation of the moving element with a spring ring relative to the body when pumping the flushing liquid, exclusion of emergency situations due to the possibility of forced movement of the moving element to the closed state by increased annular pressure.

3 cl, 1 dwg