ANNULAR BARRIER WITH ANTI-COLLAPSING UNIT Russian patent published in 2018 - IPC E21B33/127 

FIELD: soil or rock drilling; mining.

SUBSTANCE: group of inventions relates to an annular barrier, a well system, a method for isolating a zone to provide and maintain zone isolation between a first zone having a first pressure and a second zone having a second borehole pressure. Annular barrier is designed to expand in the annulus between the borehole tubular structure and the borehole wall to provide zone isolation between the first zone having a first pressure and the second zone having a second borehole pressure. Annular barrier comprises a tubular metal part for mounting as part of the well tubular structure, the tubular metal part having an outer face; an expandable sleeve surrounding the tubular metal part and having an inner surface facing the tubular metal part and an outer surface facing the wall of the borehole, each end of the expandable sleeve being connected with the tubular metal part; and an annular space between the inner surface of the expandable sleeve and the tubular metal part, the annular space having a space pressure. Annular barrier comprises an anti-collapsing unit comprising an element movable at least between a first position and a second position. Anti-collapsing unit has a first inlet which is in fluid communication with the first zone, and a second inlet which is in fluid communication with the second zone. Anti-collapsing unit has an outlet which is in fluid communication with the annular space. In the first position, the first inlet is in fluid communication with the outlet, equalising the first pressure of the first zone with the space pressure. In the second position, the second inlet is in fluid communication with the outlet, equalising the second pressure of the second zone with the space pressure.

EFFECT: technical result is the creation of an improved annular barrier.

20 cl, 11 dwg