Use of Taguchi method to study a robust design for the sectioned beams curvature during rolling

Finite element DEFORM™ 3D software is employed to examine the plastic deformation behavior of V-sectioned and T-sectioned porous beams at the roll gap under various rolling conditions. The finite element code is based on a rigid–plastic model in which it is assumed that the rolls are rigid bodies and that the temperature change induced in the beams during rolling is sufficiently small that it can be ignored. The analytical model is used to systematically examine the effect of the inclination angle of the roll profile, the friction factors between the rolls and the beam, the roll radii and the angular speed of the upper and lower rolls on the curvature of the rolled beam, the rolling torque, the effective strain, the effective stress and the variation of density of the rolled product at the exit. The Taguchi method is employed to design the rolling parameters to optimize the curvature of the beams. The analytic results have shown that: (1) the inclination angle of the inner part (i.e. vacancy) of the upper roll, the friction factor of the lower roll, the angular velocity of the lower roll and the roll radii, respectively, all have a significant influence upon the curvature of the rolled V-sectioned product, κ = 1/ra; (2) the reduction ratio of the porous beam, the friction factor of the lower roll, the angular velocity of the lower roll, and the roll radii, respectively, all have a significant influence upon the curvature of the rolled T-sectioned product, κ = 1/ra.