Welding method and device for cold arc welding of gas shielded welding of thin plate

The invention relates to a welding method and a welding device for cold arc welding of gas shielded welding of a thin plate. A welding pistol with dual-layer shielding gas is adopted in the device, namely a cooling gas protection cover is arranged on the outer surface of a gas protection cover of an ordinary welding pistol; the protection gas has two branches; normal-temperature gas is used in a first branch (an inner layer); cooled gas is used in a second branch (an outer layer) and used for quenching part of a high-temperature weld joint area and part of a welding heat affected area to make the part of the areas sharply contracted, a strong stretching effect of the weld joint area is produced, the generated compressed plastic deformation is compensated, the welding stress and deformation are dynamically controlled, and unstable deformation of a thin-plate element is prevented. According to the welding method and the welding device for cold arc welding of gas shielded welding of the thin plate, the purposes of controlling the weld joint quality and reducing the welding deformation can be realized by reducing weld heat input, and part of the weld joint can be sharply cooled after the weld joint is formed to fulfill the purpose of reducing the welding deformation. Moreover, the operation is more flexible.