METHOD FOR KILLING AND DECOMMISSIONING INJECTION WELL FOR REPAIRS Russian patent published in 2023 - IPC E21B43/12 

FIELD: oil industry.

SUBSTANCE: invention can be used for killing and decommissioning injection wells, as well as emptying a string of lifting pipes in emergency situations. A method for killing and decommissioning an injection well with a string head and injection fittings with shut-off devices includes lowering a pipe string with a packer into the well, installing a packer above the well perforation section, connecting the pipe string with injection fittings to form a closed annulus, and feeding into the well through the string fluid pipes to maintain reservoir pressure. Next, stopping the supply of fluid to the formation by closing the shut-off device, emptying the fluid from the well into a container, ensuring that the pressure at the wellhead is reduced below atmospheric pressure. Through the shut-off device of the injection valve, a weighted liquid is supplied into the well, ensuring pressure at the bottom of the well above the reservoir pressure. A perforator is lowered into the pipe string and perforation is performed in the lower part of the pipe string above the packer location. Next, the perforator is removed, the shut-off device of the column head is opened, followed by the supply of weighted liquid into the well, emptying the liquid from the annulus into the container.

EFFECT: preventing a decrease in the reservoir pressure of production wells by maintaining increased pressure at the bottom of the injection well.

2 cl, 2 dwg