摘要 |
<p>A lightweight hollow member having a high strength such as at least 780 MPa, a complicated shape which can be applied to automotive parts, a high stiffness, and excellent impact properties, and a manufacturing apparatus and method which can form the hollow member by simple steps and which use relatively small and inexpensive forming equipment are provided. The manufacturing apparatus 10 has a feed unit 11 which feeds a hollow steel material being worked 20 having a closed transverse cross-sectional shape in its lengthwise direction, a support unit 12 which supports the material being worked 20 while it is being fed at a first position A, a heating unit 13 which heats the material being worked 20 at a second position B, a transverse cross-sectional shape modifying unit 14 which carries out working to modify the transverse cross-sectional shape of the material being worked 20 at a third position C, and a cooling unit 15 which cools the material being worked 20 at a fourth position D.</p> |