How does a spot welding machine work ?

The working principle of spot welding machine is to use electric current and pressure to join metal pieces together through spot welding points. The following is the basic working principle of the spot welding machine:
 

1. Preparation: Place the metal pieces to be welded on the workbench of the spot welding machine, and ensure that there is an appropriate contact area between the metal pieces.

2. Electrode contact: The electrodes of the spot welding machine (usually made of copper) respectively clamp the metal sheets to be welded, so that the current can enter the metal sheets through the electrodes.

3. Apply pressure: The spot welder applies a certain amount of pressure to make the electrode and the metal sheet in close contact to ensure the smooth transmission of current and the stability of the welding joint.

4. Apply current: The spot welder applies high current pulses through the electrodes, usually in the millisecond range. This causes the metal in the welded joint to heat up and melt quickly.

5. Melting and solidification: As electric current passes through the welded joint, the metal at the joint quickly heats to high temperatures and melts. Once the current is disconnected, the metal cools rapidly and solidifies, forming a weld.

6. Detection and control: Some spot welding machines are equipped with detection and control systems for the welding process, which can detect the quality of welded joints and make adjustments and controls as needed.

The working principle of the spot welding machine is based on the principle of resistance heating and pressure connection. Through the action of current and pressure, the metal sheets are instantly melted and connected at the welding joint to form a strong welding joint. This welding method is usually suitable for situations where the metal sheets are thin and need to be connected efficiently, such as in automobile manufacturing and home appliance manufacturing.