Micro-damaged tube fetching device and process for heat transfer tube of shell-tube heat exchanger

The invention belongs to the technical field of machining, and particularly relates to a micro-damaged tube fetching device and process for a heat transfer tube of a shell-tube heat exchanger. By means of the novel micro-damaged tube fetching device and process for the shell-tube heat exchanger, on the premise of minimizing the overall damage to the heat exchanger, a tube expansion transition zoneof the heat transfer tube is completely taken out. The heat transfer tube taken out by the process contains the complete tube expansion transition zone, and the original state of the transition zoneis maintained to the maximum extent, so that the performance evaluation and failure mechanism research of the heat transfer tube after long-term operation are facilitated. In addition, after taking out the tube expansion transition zone of the heat transfer tube with the process, the overall damage to the heat exchanger is small; when a tube hole after fetching the tube is blocked by a welding/mechanical plug, the heat exc