Pneumatic butt welding machine is also called current welding machine or resistance bump welding machine. Using the resistance between the two workpiece surfaces, the use of low voltage and large current, so that the surface of the two metal materials connected to each other immediately hot to melt and combine.
Electric welding machine (generally refers to manual arc welding) is to use the high temperature arc caused by the positive and negative poles in an instant short circuit fault to melt the welding material and welding raw materials on the electrode, so that the object is closely combined. Its structure is very simple, is a large power transformer. Welding machine generally according to the output switching power supply type can be divided into two kinds, one is ac, one is DC power supply. It uses the basic principle of inductor, inductor quantity in the access and break time caused by a great working voltage change, the use of positive and negative poles in a short circuit fault caused by the high voltage arc to melt the welding material on the electrode, so that they achieve the goal of molecular fusion.