DEVICE FOR INCREASING OIL RECOVERY OF WELL FORMATIONS Russian patent published in 2019 - IPC E21B43/18 E21B28/00 E21B34/06 

FIELD: oil industry.

SUBSTANCE: invention relates to oil and gas industry and can be used for increasing oil recovery of well formations. Device comprises a cavitation-wave generator, which is lowered into the interval of productive formation perforation, connected to a lower end of the flushing pipes column through a multi-cycle circulating valve assembly, as well as wellhead sealing and lowering and lifting equipment, a container with working fluid and a pump unit for its injection into the flushing pipe string. According to the invention, the multi-cycle circulating valve assembly is made in the form of a tubular coupling body having in its upper part a blind hole located along its main longitudinal axis, equipped with at least one radial channel hydraulically connected to the annular space, wherein the top of the blind hole is equipped with a seat for the spring-loaded locking element located above it with the annular clearance, and the working fluid flow from the flushing pipe column to the cavitation-wave generator is performed by means of at least one circumferentially located in the body of the longitudinal through hole with the non-circular cross section.

EFFECT: technical result consists in reduction of labour intensity and expenditure of time for performance of cavitation-wave treatment of bottomhole zone of productive formations of wells.

1 cl, 4 dwg