For example, the heat of the helium arc is large, and it is protected by helium or argon-helium mixed gas, or by gas welding with a large-scale consumable electrode. In the case of a DC connection, "cathode cleaning" is not necessary.
For the purpose of anti-corrosion work, the surface of these workpieces needs to be sprayed and treated, and spray painting is a good solution to the surface. Isolated from air and water.
In the gas welding, flux is used, and the oxide film on the surface of the molten pool is constantly picked up by the welding wire during the welding process.