Method for maintaining corrosion protection of zinc electroplated thin steel sheet with ZE-Mg phase and corrosion-protecting primer during spot welding comprises applying material which evaporates during welding, cooling coated sheet

摘要

Method for maintaining corrosion protection of zinc electroplated thin steel sheet with a ZE-Mg phase and a corrosion-protecting primer during spot welding comprises applying to the position where the spot weld is required and the area of the bead around it a material which evaporates during welding, cooling the coated sheet. An independent claim is included for apparatus for carrying out the method which has two nozzles (2) which apply the material to the coated surface (4) of the sheet. These are mounted on either side of the electrode (1) on carriages (3) which can be moved up and down and are at an acute angle to the surface of the sheet.