| 摘要 |
PROBLEM TO BE SOLVED: To dispense with a post-treatment process of the painting, and to improve the corrosion resistance on the inner surface side in manufacturing a tank, etc., by welding an aluminum-plated steel sheet. SOLUTION: In manufacturing a fuel tank by welding circumferential edge flange parts 2a, 3a of a pair of upper and lower semi-spherical bodies 2, 3 made of aluminum-plated steel sheets which are aluminum-plated on each side, a step (d) is provided on the flange part 3a on one side, and a clearance part formed by the step (d) is irradiated with the laser beam and welded. Unnecessary composition such as Al generated on the lapped side (opposite side) is removed into the clearance, and the quantity of Al, etc., to be mixed in a welded part is reduced to improve the weld strength. |
