| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a torsion beam using an electroseamed steel pipe without seam buckling and deterioration of appearance by the same, and deterioration of fatigue characteristic.SOLUTION: In a manufacturing method of a torsion beam where an electroseamed steel pipe is pressed so that a cross-sectional shape becomes V-shaped, press working is performed while a seam position of the electroseamed steel pipe is a range: 15-25° relative to a V-shape apex of 0°. Therefore, the torsion beam is provided in which seam buckling can be suppressed and fatigue characteristic can be improved compared with a conventional torsion beam where the seam position is 45°.SELECTED DRAWING: Figure 1 |
