WELL COMPLETION METHOD Russian patent published in 2023 - IPC E21B43/10 E21B33/14 

FIELD: well drilling.

SUBSTANCE: isolation and fastening of reservoirs of oil and gas wells in the process of their completion in the presence of aquifers located above and below the productive formation, with a zone of the oil-water contact zone (hereinafter OWC). The well completion method includes running a casing string into the well and cementing the well, followed by a secondary opening of the productive formation. Preliminarily, according to the available data on previously drilled wells in this area, the thickness of the productive and aquifer and the location of the oil-water contact are determined, a water swellable packer is selected with a length that allows covering the entire thickness of the productive formation and blocking the upper and lower aquifers for a length of at least 2 meters from the OWC zone. Then, the following assembly is installed on the casing from the bottom up: a casing shoe, a water swellable packer, a staged cementing collar. The casing string is lowered with assembly into the well, a water swellable packer is placed in the interval of the productive formation and the aquifers located above and below it, the well is cemented through the staged cementing collar. After completion of cementing, the well is left to wait for the cement to harden and for the activation of the water swellable packer. After activating the water swellable packer inside the casing, a staged cementing collar is drilled. Next, the perforator is lowered into the interval of the productive horizon and perforated through a water swellable packer.

EFFECT: isolating water-bearing formations located above or below the productive formation with guaranteed quality, thereby excluding the occurrence of behind-the-casing flows, reducing the water cut in production during long-term operation of wells by ensuring tightness and reliability of isolation and fixation of reservoirs, as well as increasing the productivity of wells for by achieving hydraulic perfection of the productive part of the well.

1 cl, 1 dwg