How does the resistance spot welder weld steel with high quality and high efficiency?

News 2022-06-14 63

In the production of resistance welding equipment, low-carbon steel, medium-carbon steel, high-carbon steel, low-alloy steel and their combinations are welded. The standardized selection can refer to the welding specification of low-carbon steel. The spot welding machine has high welding strength. For alloy steel, the friction pressure and top pressure should be increased, and the friction time should be extended appropriately.

When the spot welder welds dissimilar steels with large differences in high-temperature strength or some dissimilar metals that do not produce brittle alloy layers, in addition to adding a mold to the material with low strength at high temperatures, the friction time should be extended appropriately to increase the friction pressure. and upsetting pressure. When welding dissimilar metals with a brittle alloy layer, it is necessary to use a mold to seal the street metal, reduce the welding speed, and increase the friction pressure and upsetting pressure.

When welding large-diameter workpieces, under the premise of constant friction speed, the speed should be reduced accordingly, the diameter of the workpiece will expand, the friction pressure will be unevenly distributed on the friction surface, the friction deformation resistance will increase, and the expansion of the deformed layer will take a long time. Therefore, under the premise of ensuring that the amount of friction deformation remains unchanged, a relatively large friction pressure or a relatively long friction time is required. When the spot welder welds carbon steel and low alloy steel workpieces with different sections, due to the different thermal conductivity standards, the temperature distribution on the joint and the thickness of the deformed layer are different. In order to ensure the welding quality, strong specification welding should be used.

Welded medium carbon steel. For high-carbon steel and low-alloy steel, in order to avoid obtaining annealed structure in the weld and reduce the post-weld tempering process, a weaker welding specification should be selected. When the spot welder welds the pipe, in order to reduce the internal burrs, on the premise of ensuring the welding quality, every effort should be made to reduce the amount of friction deformation and upsetting deformation.