Aluminum and aluminum alloys have strong thermal conductivity, large heat capacity, large linear expansion coefficient, low melting point, low high temperature strength and great welding difficulty, which should be paid attention to. Some measures should be taken to ensure the welding quality. 2 Pipe fittings and welding wires should be cleaned. Use child soldiers to clean the welding wire and the surface within 50mm on both sides of the breach, and brush off the oxide film on the surface with stainless steel wire to expose the metallic luster. The cleaned breach should be welded within 2 hours, and the cleaned welding wire should be put into the unused cylinder and used up within 8 hours, otherwise it should be reprocessed. , the above content comes from the network.