Abstract: With the continuous development of the central heating mode, the long-distance heat transmission pipe network is a vital part of heat supply, and its stable and efficient transmission provides a guarantee for industrial and residential heat. When the thermal pipeline leaks, it takes a lot of time to carry out maintenance and repair work, and the speed and process of maintenance greatly affect industrial production and residents' lives. Therefore, automatic welding equipment technology has gradually emerged and developed in this field, and has now been used as the main technical means of pipeline maintenance and repair. The purpose of this paper is to discuss the common damage and defects of long-distance heat pipelines, repair methods, and the technical development status and prospect of maintenance and repair automatic welding equipment, so as to provide a useful reference for practitioners in the field of engineering.