SPOT WELDING METHOD AND WELDER

摘要

PROBLEM TO BE SOLVED: To provide a spot welding method and welder which has long lifetime and enables welding spot interval to be constant, especially suitable for spot welding corrosion resistant foil metal to rail which forms current-carrying portion of return line current bridged network in the rail of railroad. SOLUTION: A metal plate 1 disposed on backing material 2, a disc-form electrode rotating to transfer on the metal plate 1, intermittent current from the disc-form electrode passing into the spacing between the metal plate 1 and the backing material 2, nuggets 5 are formed successively on the contact surface between the metal plate 1 and the backing material 2.