The welding method of welding the resistor to make the workpiece under a certain electrode pressure and melt the contact surface between the two workpieces by using the resistance heat generated when the electric current passes through the workpiece. Large currents are usually used. In order to prevent the arc on the contact surface and to press the weld metal, pressure is always applied during welding.

The whole process can be divided into startup, fast down, slow down, pressure up, pressure welding, micro loop, quick return and end. After starting, the motor drives the welding electrode to drop fast close to the workpiece, and then to slow down when approaching, and to continue to press into the starting link after touching the workpiece.
 
In the welding process, the workpiece will melt due to the heat generation of the resistor. In order to ensure the welding effect to continue decline and achieve keeping the set pressure,  
the motor recovers slowly at a distance from the workpiece, and then returns to the origin quickly, completing a period after welding.