Spot Welders, Professional Electric Spot Welders

The points welders, electric resistance welders or even pressure calls, generate heat in the points of contact between two metal parts for electrical resistance. The heat developed by the current is proportional to the electrical resistance of the conductors .

Spot resistance welding is generally used to weld steels and is carried out in three stages :

1. the electrodes are brought close to the surface of the parts to be welded and the necessary pressure is exerted to compress the parts together;
2. a predetermined current is passed through the electrodes. The welding is controlled by adjusting the intensity of the current and the time during which the current crosses the contact point.
3. the electrodes are moved away from the surfaces of the piece, which are thus joined by means of a small molten and solidified volume. At the point of contact between two metal objects, the resistance is greater than that of the metal, therefore the passage of current causes the area close to the contact to overheat and, if the current is high enough, the two objects are melted and therefore welded. .