METHOD FOR ELIMINATING FLOWS BEHIND THE CASING IN A PETROLEUM PRODUCTION BOREHOLE FROM AN UNDERLYING AQUIFER Russian patent published in 2022 - IPC E21B33/138 E21B33/16 E21B43/00 

FIELD: petroleum industry.

SUBSTANCE: claimed is a method for eliminating flows behind the casing in a petroleum production borehole from an underlying aquifer. Method for eliminating flows behind the casing in a petroleum production borehole from an underlying aquifer includes plugging the borehole. Method also includes extracting the downhole equipment; installing a packer plug in the interval of the bottom of the productive formation. A blocking agent is pumped into the perforation channels through the lowered tubing string with the packer; the tubing string with the packer is then raised. Then the packer plug is drilled out. A slot perforator is lowered on a drill pipe string, and perforation is made in the aquifer interval, forming longitudinal slot channels. Then the drill pipes with a perforator are lifted, and an assembly consisting of a tubing string, a wash shoe, and a packer is lowered. A water insulation composition is then injected and pumped into the slot channels. Then the assembly is lifted, and the borehole is left until the cement solidifies. Then a smaller-diameter casing string is lowered into the borehole from the bottomhole to the overlying bed of the aquifer, cemented, and left until the cement solidifies.

EFFECT: created reliable barrier for the ingress of reservoir waters in the space behind the casing between the casing and the rock.

1 cl, 5 dwg