WELL COVERING SYSTEM, WELL SYSTEM CONTAINING SUCH WELL COVERING SYSTEM, AND METHOD FOR SEALING DAMAGED AREA OF WELL TUBULAR METAL STRUCTURE Russian patent published in 2023 - IPC E21B33/124 E21B23/06 E21B33/126 

FIELD: borehole capping systems.

SUBSTANCE: group of inventions relates to a borehole capping system, a borehole system containing such a borehole capping system, and a method for sealing a damaged area of a borehole tubular metal structure. The well shut-off system includes: a shut-off assembly having a first end, a second end closest to the top, an inner surface, a first hydraulic expansion casing barrier, and a second hydraulic expansion casing barrier; a downhole tool assembly having a hydraulically controlled placement tool for releasable connecting the downhole tool assembly to a second end of the shutoff assembly; and a closure module configured to close the first end of the closure assembly. The downhole tool assembly further comprises a first sealing module located above the first hydraulic expansion casing barrier and the second hydraulic expansion casing barrier and configured to provide a seal against the inner surface of the closing assembly. The downhole tool assembly further includes a sealing device located above the placement tool and the first sealing module. The sealing device has an annular sealing member having a first outer diameter in a first state and a second outer diameter that is larger than the first outer diameter in a second state to provide a seal against the inner surface of the downhole tubular metal structure. The sealing device contains a fluid channel for fluid connection of the internal volume of the shut-off assembly with the downhole tubular metal structure above the sealing device, when the sealing device is in the second state, for expanding the first hydraulic expansion casing barrier and the second hydraulic expansion casing barrier.

EFFECT: creating an improved downhole sealing system for sealing a damaged zone in a downhole tubular metal structure for a shorter period of time.

15 cl, 12 dwg