AC risistance welding is the welding method with which the end surface of two parts are pressed tightly,and the risistance heat is used to heat up the surface to the pasticized status,and then the upset forging pressure is quickly applied(or without applying the upset forging pressure but only keeping the welding pressure)to complete the welding. The welding process is simple,Just position the parts,and depress the seitch with foot.The welding efficiency is high. The welded joint is smooth,and the burrs are small: The structure is compactly designed,and it can be easily adjusted to weld parts wlth different thickness:The special butt welding control circuits ensure the welding quality: It is mainly used for thr butt welding of metal materias (such as iron wires,pipes,etc.)with a small section area