Abstract: A method for removing metallic plugs from conduits such as the heat exchanger tubes in a nuclear steam generator is disclosed herein. In such tubes, plugs formed from a cylindrical shell of Inconel are radially expanded in sealing engagement with the open end of an Inconel tube mounted in a tubesheet by pulling down a cork-shaped expander element disposed in wedging engagement with the shell. The method of the invention removes such plugs by pushing the expander element from the open end back to the closed end of the shell, and then heating the shell to a temperature which substantially lessens its tensile yield while applying a tensile force along the longitudinal axis of the plug shell sufficient to elongate it. In the method, an electrically conductive push-rod is utilized which simultaneously conducts a substantial current of electricity through the plug shell while pushing against the closed end thereof.