The process of spot welding is to open the cooling water and clean the weld surface, after the assembly is accurate, it is fed into the upper and lower electrodes, exerting pressure to make them contact well; Electricity causes the two workpieces to contact the surface to be heated, partially melted, to form a fusion core; Welding current, electrode pressure, power-on time and electrode working surface size of welding process parameters have a significant impact on the quality of weld.
The spot welder uses the high temperature arc produced by the positive and negative poles in an instantaneous short circuit to melt the welding material between electrodes to achieve the purpose of combining them. Spot welding machine structure is very simple, plainly is a high-power transformer, the 220V AC into low voltage, large current power supply, can be DC can also be AC. Welding Transformer has its own characteristics, that is, the characteristics of a sharp drop in voltage.
After the electrode ignition voltage drop, welding machine work voltage adjustment, in addition to a 220/380 voltage conversion, two times coil also has tap conversion voltage, but also useful iron core to adjust, adjustable iron core. Welding machine is generally a high-power transformer, the Department of the use of inductance made of the principle. When the inductance is connected and disconnected, a huge voltage change occurs, using the High-voltage arc produced by the positive and negative poles in an instantaneous short-circuit to melt the solder on the electrode. To achieve the purpose of integrating them.