Patent ID: 6283211
Filing Date: 2001-09-04
Classification: E21B

Abstract:
A method for lining a portion of a casing affixed within a well bore a distance below an upper end of the well bore, the method comprising:providing a viscoelastic pipe having an upper end, a lower end, and an outer diameter greater than the inner diameter of the casing;reducing the outer diameter of the pipe so that the outer diameter of the pipe is less than the inner diameter of the casing, wherein the step of reducing the outer diameter of the pipe comprises:disposing an upper connector assembly in the upper end of the viscoelastic pipe, the upper connector assembly having an outer diameter less than the inner diameter of the viscoelastic pipe;connecting a guide shoe to the upper end of the viscoelastic pipe, the guide shoe having an inner diameter less than the inner diameter of the viscoelastic pipe such that a support shoulder is formed by the guide shoe;linking the upper connector assembly to a carrier section of viscoelastic pipe;passing the viscoelastic pipe and at least a portion of the carrier section of viscoelastic pipe through a roller reduction unit comprising a plurality of banks of rollers wherein the banks of rollers cooperate to form a substantially frusto-conically shaped passageway such that the outer diameter of the viscoelastic pipe is gradually reduced as the viscoelastic pipe is passed therethrough;suspending the reduced viscoelastic pipe from the upper end of the well bore;detaching the carrier section of viscoelastic pipe from the reduced viscoelastic pipe;connecting a lower end of a work string to the upper connector assembly, the work string having an upper end connected to surface equipment and a string mill at the lower end thereof; andlowering the viscoelastic pipe into the casing with the work string;passing the reduced viscoelastic pipe into the casing to a predetermined depth where the upper end of the reduced viscoelastic pipe is positioned a distance below the upper end of the well bore; andallowing the reduced viscoelastic pipe to expand against the internal wall of the casing.