In twenty-first Century, China vigorously promoted the research and construction of AC and DC transmission technology in order to ensure the optimal allocation of energy resources in a large scale[1]. The transmission line is the core of the power grid, which plays the role of transmission, transformation and distribution of electric energy, and each tower is the core component of the transmission line. At present, because the force of the steel tube tower is more reasonable, it has been widely used in the construction of UHV, and the link of the key position of the steel tube tower is welded, so the quality of the welding is of great significance to the construction of the whole network frame. For the welding of the steel tube tower, the manual semi automatic CO2 gas shielded welding is mostly used. Because of the characteristics of the protective gas medium, it is easy to produce a large number of splashes and not easy to clean up during the welding process. It is easy to make the weld penetration rate and forming decline. It is effective to use the melting pole mixture gas protection welding, If we can make a scientific welding standard, it is possible to reduce the occurrence of welding spatter, achieve the purpose of improving welding efficiency and controlling manufacturing cost.