An improved system for removing a plug from the open end of a heat exchanger tube in a nuclear steam generator is disclosed herein. It is particularly adapted for removing a plug formed from an elongated, cylindrical shell of Inconel.RTM. having a closed end, an open ends, and an expander element that radially expands the shell when axially drawn from the clossed to the open end of the shell. The system comprises an expander remover for axially pushing the expander element from the open end completely through the closed end of the plug shell, and a TIG torch for creating beads along the longitudinal axis of the plug shell which relax the engagement between the plug shell and the tube after the weld beams harden. Finally, the system includes a plug puller for pulling the loosened plug from the tube. The expander remover and plug puller maybe remotely operated by means of a robotic arm, and a compliance coupling is provided to facilitate alignment between these tools and the plugged end of a selected heat exchanger tube.