RESISTANCE WELDING METHOD FOR GALVANIZED STEEL SHEET, ELECTRODE TIP OF METHOD FOR RESISTANCE WELDING FOR GALVANIZED STEEL SHEET

摘要

PURPOSE: A resistance welding method of a galvanized steel sheet and a regenerating method of an electrode tip for the galvanized steel sheet resistance welding are provided to form into a canonical shape without polishing or removing a deformation part or a rubbed-off part of the electrode tip; thereby preventing the lifetime of the resistance welding of the electrode tip being shortened. CONSTITUTION: A resistance welding method of a galvanized steel sheet and a regenerating method of an electrode tip for the galvanized steel sheet resistance welding comprise the following steps. A CU-ZN alloy thin layer is formed on a front end surface of a pair of electrode tip. An end unit outer periphery surface and an end surface of each electrode tip, which is entered into each shaping chamber, is formed into a canonical shape. A CU-ZN alloy film formed on the end surface is adjusted into a fixed film thickness. By a pair of electrode tip in which the film thickness of the CU-ZN alloy film had been adjusted, the overlapped galvanized steel sheet is resistance-welded by the applied current in a status of supporting with the fixed pressure. The end surface of each electrode tip is entered into the shaping chamber of an electrode tip regenerating inlet. The end unit outer periphery surface of each electrode tip is formed into the canonical shape, and at the same time, a Zn-Fe alloy pellicle formed on the Cu-ZN alloy film is adjusted to have a fixed film thickness. After the adjustment of the Zn-Fe alloy pellicle by the Zn-Fe alloy pellicle thickness adjusting process, the resistance welding processes is reactivated and the resistance welding of the galvanized steel sheet is continued. [Reference numerals] (AA) Activated carbon electrode chip installation; (BB) Copper-zinc alloy film formation process; (CC) Copper-zinc alloy film thickness control process; (DD) Resistance welding process; (EE) Zinc-iron alloy film thickness control process