| 摘要 |
PURPOSE:To improve the corrosion resistance of the lap resistance weld zones of surface-coated steel plates by welding while enclosing the outside surfaces of the steel plates to be heated in nonoxidative atmospheres etc. then covering the outside surfaces of the weld zones with metals having a m. p. lower than that of iron. CONSTITUTION:Upper, lower chambers 3, 3' are provided at the heating parts on the outside surfaces of materials 1, 1' to be welded, and shielding gas nozzles 4, 4' are provided to the chambers 3, 3'. Nonoxidative or reducing gases 5, 5' are supplied to these. The materials 1, 1' are welded by a pair of disc-like electrodes 2, 2' which can be internally cooled with water. Wire-, powder- or paste- like low m. p. metals 7, 7' are added and supplied to the heated outside surfaces of the weld zones through feed pipes 6, 6'. |
