RETURN VALVE OF ELECTRIC CENTRIFUGAL UNIT AND CLEANING METHOD OF FILTER AT PUMP SUCTION Russian patent published in 2015 - IPC E21B34/06 

FIELD: oil and gas industry.

SUBSTANCE: valve includes a body with the upper and lower connection threads, valve saddle fixed rigidly inside the body, thrust bush and washer with central and peripheral openings fixed in body by a locking ring, disc valve with rod passing through the central opening of washer, driving washer and spring installed between washer and driving washer. The rod of disc valve is made hollow with horizontal openings in the upper section connecting the tubing area over the valve with the area below the valve. The driving washer is a stepped one, and its lower part with less diameter forms a sliding friction couple with outer surface of the hollow valve rod. In the upper part of the driving washer with screwed cover and centralisers there are horizontal openings with diameter larger than diameter of openings in the valve rod. In the upper part of the valve rod from outside there is a locking ring and O-rings of elastic material, which are placed at both sides of horizontal openings in the valve rod.

EFFECT: improved efficiency of filter cleaning.

2 cl, 3 dwg