Resistance WeldingResistance welding for wire mesh machines is a method using 2 wires ( line and cross ). Resistance welding is a method to weld a wire metal sheets which can be used in the reinforcing industry or for industrial applications. Two copper electrodes are simultaneously used to clamp the wires in the sheets together and to pass current through the wires. When the current is passed through the electrodes to the wires, heat is generated due to the higher electrical resistance where the surfaces contact each other. As the heat dissipates into the work, the rising temperature causes a rising resistance, and the resistance welding heat is then generated by the current through this resistance. The water cooled copper electrodes remove the surface heat quickly, since the copper is an excellent conductor. The heat in the center has nowhere to go, as the metal of the workpiece is a poor conductor of heat by comparison. The heat remains in the center, melting the metal from the center outward. As the heat dissipates throughout the workpiece in less than a second the molten, or at least plastic, state grows to meet the welding tips. When the current is stopped the copper tips cool the spot weld, causing the metal to solidify under pressure. |