Electric welding, also known as electric welding machine, mainly relies on the current to dissolve the welding rod and fill the welding ashes existence rack. But spot welder mainly relies on the current to dissolve the surface of the two metals for welding, can only be applied to the welding method of overlapping metal blocks, feel the welding is not strong, including spot welder welding before the need to clean the welding surface to ensure clean, otherwise easy to weld. Welder is the use of instantaneous short circuit when the positive and negative poles generated by the high temperature on the welding material and welding material, so that the purpose of the contact bond. Its structure is very simple and is a high-power transformer. Welding machine can generally be divided into two types of output power, one is AC power, the other is DC power.
There are three types of spot welders in common use: DC, AC and pulse. The working principle of the spot welder is that the welded parts are combined and welded by the resistance heat generated by the contact surface of the joint and the adjacent area.
Advantages of spot welding machine: spot welding machine converts electrical energy into heat energy, short heating time, concentrated heat, small heat affected area, small deformation and stress, usually no need to arrange correction and heat treatment process after welding. No need for filler metals such as welding rod and wire, welding materials such as oxygen, acetylene and argon, etc.. And the welding cost is low.
The spot welder uses the high temperature caused by a transient short circuit of the positive and negative electrodes, and the electric welder uses current resistance to heat through thermal welding. Therefore, although the two work on different principles, there is still a significant overlap in the specific range of applications.