Edgewise Bending of Flat Bar by New “Bend-Rolling” Process

Abstract

The bend-rolling process, which is a new method for bending a flat bar or a narrow strip in its plane, is developed In this process, a straight flat bar is rolled between horizontal rolls using a conventional rolling mill and the outgoing rolled bar is forced to bend in lateral direction with a restricting vertical roll placed at the exit side of the mill. The curvature of product is determined by the position of adjustable restricting roll, and the required force acting on the restricting roll increases with the increase in curvature of product and decreases remarkably with the increase in reduction in thickness by rolling. The rolling force is determined by the reduction in thickness independently of the curvature of product. These experimental results are predicted sufficiently by a theoretical analysis. The notable advantage of the bend-rolling process is that the curved product of rectangular cross-section with close tolerance, of which curvature is comparable to the limiting curvature of the conventional edgewise bending method, is obtained by using a conventional rolling mill supplemented simple restricting rolls. This process is applicable to bending several kinds of sections.