Method for manufacturing shaped steel the cross-sectional shape of which changes in the longitudinal direction, and roll forming device

摘要

A roll forming device, for roll forming for the purpose of manufacturing shaped steel the cross-sectional shape of which varies in the longitudinal direction, is equipped with: first die rolls having an annular ridge part the cross-sectional shape of which varies in the circumferential direction; second die rolls having an annular groove part the cross-sectional shape of which varies in the circumferential direction; and a drive device for the first die rolls and the second die rolls. A gap is provided at the side surfaces of the annular ridge part of the first die rolls, across the entire circumference in the circumferential direction, such that the gap with respect to the side surfaces of the annual groove parts of the second die rolls widens inward in the radial direction.

主权项

1. A method of producing a shaped steel which varies in cross-sectional shape in a longitudinal direction from a sheet by roll forming, comprising:
a step of preparing a first rolling die which has a rotation shaft and an annular ridge part which varies in cross-sectional shape in a circumferential direction which is centered about said rotation shaft; a step of arranging said first rolling die so that the rotation shaft of said first rolling die becomes perpendicular to a sheet feed direction; a step of preparing a second rolling die which has a rotation shaft and an annular groove part which varies in cross-sectional shape in a circumferential direction which is centered about said rotation shaft; a step of arranging said second rolling die so that a gap which is equal to a thickness of said sheet is formed between said first rolling die and second rolling die and the annular ridge part of said first rolling die and the annular groove part of said second rolling die engage; a step of making said first rolling die and said second rolling die rotate synchronized; and a step of feeding the sheet between said first rolling die and second rolling die, wherein side surfaces of the annular ridge part of said first rolling die are provided with a relief so that the gap with respect to side surfaces of the annular groove part of the second rolling die broadens inward in a radial direction throughout the circumference.