SLIDING SLEEVE DOWNHOLE SYSTEM Russian patent published in 2023 - IPC E21B34/14 E21B43/12 

FIELD: oil and gas industry.

SUBSTANCE: tools for well completion. The downhole system for well completion comprises a downhole tubular metal structure located in a wellbore having wellbore pressure. Downhole tubular metal structure contains an inner surface and an inner volume having the pressure of the inner volume, an opening and an axial extent. The sliding sleeve is movable inside the downhole tubular metal structure and along the axial extent between the first position, in which the sliding sleeve plugs the hole, and the second position, in which it is possible to transfer fluid between the wellbore and the internal volume of the downhole tubular metal structure. The sliding sleeve contains the first sealing element located on the outer surface on one side of the hole, and the second sealing element located on the outer surface on the other side of the hole in the first position. The pressure reducing mechanism is associated with the first sealing element to reduce the pressure exerted on the first sealing element when the sliding sleeve is moved from the first position to the second position. The pressure reducing mechanism is a labyrinth seal. The pressure reducing mechanism is at least one slot passing through the downhole tubular metal structure and extending along the axial extent from the hole in the direction of the first sealing element in the first position.

EFFECT: technical result is achieved - reduction of high pressure effect on the sealing element of the sliding sleeve.

18 cl, 10 dwg