电阻焊的原理是：所有材料在有电流流过时温度都会上升，优良导体如铜，巾于电阻低，温度上升就小；不良导体如马口铁，电于电阻大，而温度上升就大，进行焊接时，马口铁从两焊接辊间经过，通过焊接辊传送焊接电流（I）、焊接力（F）及焊接速度（V），在电流的每个正、负半波， Resistance welding principle is: all materials in the current flow will rise when the temperature, good conductors such as copper, towel in the low resistance, the temperature rise is small; poor conductor such as tinplate, electrical resistance, and the temperature rise is large, the welding , The tinplate passes between the two welding rolls, and the welding current (I), the welding force (F) and the welding speed (V) are transmitted through the welding roll, and at each positive and negative half current of the current,