| 摘要 |
PURPOSE: To obtain a high joining strength in a short welding time and also to attain simplification and miniaturization of laser tack welding equipment by performing laser tack welding with an abutting part scanned with a laser beam polarized in the direction parallel to the abutting face. CONSTITUTION: In seat bar joining equipment, the tip end and the rear end of seat bars 1, 3 are cut off along the width direction of the bar by a flying shear 11 so that a linear joined face is formed. Then, the rear end face of the preceding seat bar 1 is joined with the front end face of the succeeding seat bar 3, with this linear abutting part 5 tack-welded 7 by laser welding. After that, both seat bars 1, 3 are continuously rolled through a line of rolling mills to complete the joining between the seat bars 1, 3. Accordingly, it is possible to obtain a high joining strength in a short welding time and also to attain the simplification and miniaturization of the laser tack welding equipment. In addition, misalignment is also suppressed at the time of laser tack welding in a line for rolling billets with various thickness. |
