Minimization of Energy in the Multipass Rolling Process

Abstract

This research focuses on the optimization of the flat rolling process. In order to optimize the process effectively, the existing process model has been especially enhanced—in the neutral zone where the friction changes sign over a region rather than at a point. Pressure and frictional stress distributions as well as total load and torque are thereby estimated as functions of the various rolling parameters. Roll flattening has also been taken into account. The main problem of determining the optimum design parameters of multipass rolling has been considered. The problem has been formulated and solved as a constrained nonlinear programming problem by considering the radius of the rolls, the front and back tensions as design variables. Optimum number of passes have been found, so that the total energy consumed by the tandem mill is minimized. Constraints are placed on the induced stresses, the neutral angle, the angle of bite and the deflections of the rolls, for both cold and hot rolling processes.