Anti-desoldering welding device for capillary tube of tubular heat exchanger

The invention discloses an anti-desoldering welding device for a capillary tube of a tubular heat exchanger, and relates to the technical field of capillary tube welding. The anti-desoldering welding device comprises four groups of fixed assemblies, four groups of movable assemblies, a welding assembly, an end cover positioning assembly and a bottom plate, wherein the movable assemblies and the end cover positioning assembly are tightly connected with the bottom plate; and the four groups of fixed assemblies are arranged on the different movable assemblies correspondingly, and the welding assembly is arranged on the fixed assemblies. According to the anti-desoldering welding device, the output speed of a welding wire is corrected in time, so that the output quantity of the welding wire in unit time can be always kept in a relatively stable state, and the stable output quantity of the welding wire provides a basis for standard welding. A welding gap is completely filled in a negative pressure flow guide mode,