Due to the curved surface characteristics and different materials of pipelines, various welding techniques such as arc welding, MIG welding, and TIG welding are required. In terms of type, pipelines can be divided into low-pressure pipes, light structural pipes, medium-pressure pipes, and high-pressure pipes. With multiple types and special structural features, high demands are placed on every weld, and good welding not only ensures the uniform stability of the structure but also prevents leakage of the medium inside the pipe.