Method and device for sealing a well by means of a core plug, plug for implementing the method, and extractor tool designed to remove it

摘要

Methods and apparatus for sealing a well are disclosed. The method includes introducing a plug axially into the well, with a mouth of the plug turned up and a bottom wall part turned down, the plug being positioned in the well at a desired depth. The plug is inflated by injecting a high-pressure liquid into it via its mouth so that a tubular wall part of the plug expands radially beyond its elastic limit and presses firmly and tightly against the wall of the well by a crimping effect, while its bottom wall part serves as a sealing partition, forming a tight barrier between lower and upper parts of the well that it separates. The plug has an internal axial mandrel that connects its mouth to its bottom wall, the mandrel being pierced with channels that allow injection of high-pressure liquid inside the plug via the mouth and channels.

主权项

1. A method for sealing a well by means of a plug of ductile metal, which comprises a tubular wall part whose diameter is smaller than the diameter of the well, and a bottom wall part connected to the tubular wall part, said plug having an open end forming a mouth, the method comprising the steps of introducing the plug axially into said well, with the mouth of said plug turned up and the bottom wall part of said plug turned down, the plug being positioned in the well at a desired depth, after which the plug is inflated by injecting a high-pressure liquid into the plug via the plug's mouth so that the plug's tubular wall part expands radially beyond its elastic limit and comes to press firmly and tightly against the wall of the well by a crimping effect, while the bottom wall part of said plug serves as a sealing partition, forming a tight barrier between lower and upper parts of the well that it separates, the plug having an internal axial mandrel that connects the plug's open end forming the mouth to the plug's bottom wall, the mandrel being pierced with channels that allow injection of high-pressure liquid inside the plug via the mouth and the channels, wherein use is made of the plug, wherein the axial mandrel is attached to said plug wall at upper and lower ends of the wall, so that the mandrel constitutes a spacer that can impede shortening of the plug along the axial direction during the plug's radial expansion.