Method for repairing a liner hanger, device and blank for implementation thereof

摘要

Method for repairing a hanger (D) of a liner (B), for making a leak-tight connection, the liner (B) being placed inside and in the continuation of the casing (A) of a well, the method consisting in axially positioning a metal tubular blank (1) in the well, the blank having a solid wall radially deformable beyond its elastic limit and comprising an upper cylindrical portion (10) whose outer diameter is slightly smaller than the inner diameter of the casing (A), a lower portion (13) also cylindrical whose outer diameter is slightly smaller than the inner diameter of the liner (B), and an intermediate portion (11, 12) of diameter varying between these two diameters, and causing radial expansion of at least one of these two cylindrical portions (10, 13) beyond its elastic limit so that they are applied closely and firmly and in leak-tight manner against the inner face of the wall opposite the casing (A) or liner (B).

主权项

1. A method for repairing a hanger of a liner to make the liner and hanger leak-tight, the liner being placed inside a casing of a well, wherein the method comprises, during a first phase, axially positioning a metal tubular blank in the well, the blank having a solid wall radially deformable beyond an elastic limit of the solid wall and including:
an upper cylindrical portion with an outer diameter that is slightly smaller than an inner diameter of the casing; a lower cylindrical portion with an outer diameter that is slightly smaller than an inner diameter of the liner; and an intermediate portion having a diameter between the outer diameters of the upper and lower portions, wherein the positioning step is performed so that the lower portion of the blank is housed in a mouth of the liner whilst the upper portion lies opposite a region of the casing located above the hanger, the method further comprising, during a second phase, the step of causing radial expansion of each of the upper and lower cylindrical portions of the blank beyond their respective elastic limits to thereby apply the upper and lower portions closely and firmly against an inner face of a wall of the casing and the liner, respectively, thereby establishing a leak-tight seal between the blank and each wall, such radial expansion causing deformation of the intermediate portion of the blank to cover the hanger, wherein radial expansion of the upper and lower portions of the blank is caused by a tool carrying a pair of inflatable packer bladders positioned one above the other, and sized so that an upper packer bladder is adapted to expand the upper cylindrical portion of the blank, whilst a lower packer bladder is adapted to expand the lower cylindrical portion of the blank.