Patent ID: 6923263

Claim:
A method for plugging a casing using a body of plug material into the casing on a carrier, the body of plug material having a melting point higher than the temperature of the casing to be plugged and expanding on solidification, the plug material being supported on a mandrel on which a plurality of circular flanges are spaced apart, comprising: inserting the mandrel carrying the body of plug material into the casing; heating the mandrel to a temperature higher than the melting point of the plug material so that the body of plug material melts to become molten plug material and slumps into the casing between the circular flanges; and cooling the molten material to solidify between the circular flanges, the circular flanges forcing the expanding solidifying plug material against the casing, which aids the transfer of heat between the mandrel and the plug material and reduces creep of the plug material along the casing.