Introduction of welding circuit calculation method for spot welding machine

For some weldments, resistance welding transformers with long arms or large openings between arms but with the same capacity are required. The circuit through which the welding current of the spot welding machine flows is called the welding circuit, because this circuit is directly connected to the outlet end of the secondary winding of the resistance welding transformer, so it can also be called the secondary circuit.

welding (secondary) circuit, the welding current is also reduced, so when planning and selecting a resistance welding machine, pay attention to the welding circuit. Arrangement of grading joints, moving jigs and weldments between jigs. Density and other requirements are reviewed. These parts can generally be made of copper alloys with poor conductivity but high strength. When the secondary no-load voltage is constant, when the arm is extended or the opening between the arms is increased, the loop impedance increases and the welding current decreases.

In addition, for welding magnetic materials (such as low carbon steel), the welding circuits of spot welding machines and projection welding machines are mainly composed of secondary windings of resistance welding transformers, secondary soft joints, electric arms, electric grips (spot welding machines) or welding parts (projection welding machines) of electric plates, as well as movable conductive connection points. The welding circuit of the butt welding machine is mainly composed of the secondary winding of the resistance welding transformer and the components in the secondary welding circuit. It not only transmits welding currents above 1000 amperes and 1000 amperes, but also transmits appropriate mechanical force.

Therefore, the mechanical strength or stiffness of these parts and their connection points (contact points) should be calculated. In general, the cross-section is usually larger than the cross-section required for the current density. Therefore, the planning of the welding circuit is generally based on the requirement of mechanical strength or stiffness.