METHOD FOR ELIMINATING ANNULAR CIRCULATION Russian patent published in 2023 - IPC E21B33/13 

FIELD: oil and gas industry.

SUBSTANCE: sealing of the bore hole annulus through which unauthorized communication occurs between layers, to the liquidation of unauthorized circulation behind the string - CBS. The method for liquidating the CBS includes creating holes in the well casing for injection of an insulating composition, isolating the perforation interval of the productive formation, installing a packer system in the well to isolate the perforation zone and the specified holes into which the insulating composition is pumped. The specified holes for injection of the insulating composition are created in the middle of ±12% of the distance between the perforation interval of the productive formation and the gas-bearing and/or aquifer. After creating holes in the well casing for injection of the insulating composition into the well, a process string with a packer system is lowered into the well; isolation of the perforation interval of the productive formation is carried out by installing a packer system that does not allow the insulating composition to pass through them into the well. After installing the packer system, an insulating composition is injected through the process column at least to the extent of the cement stone fractures through which the sealing process occurs. The insulating composition is forced through the process liquid in a volume not less than the volume of the process column with the possibility of preventing the insulating composition from solidifying in the process column. The insulating composition is forced through the holes created in the well casing for injection of the insulating composition into the CBS zone, displacing liquid from the cracks of the cement stone into the formations and sealing the CBS with this composition, then after waiting sufficiently for the insulating composition to set, the packer system is transferred to the transport folded state and the process column with the packer system is removed from the well.

EFFECT: creating a method for eliminating CBS, which makes it possible to simply and quickly, without loss of quality, isolate the CBS of liquid and/or gas through a one-time installation and use of downhole equipment and a one-time injection of the required volume of insulating composition.

3 cl, 4 dwg