A kinematic analytical approach to predict roll force,rolling torque and forward slip in thin hot strip continuous rolling

Abstract

A kinematic analytical approach has been developed to predict the roll force, rolling torque and forward slip in thin hot strip continuous rolling under various rolling conditions. The approach is based on formulating a velocity field in the roll bite zone that expresses the effect of interfacial friction on the distribution of axial velocity and longitudinal stresses across the strip thickness. The results obtained from the proposed approach are in fair agreement with finite element simulation results, whereas available analytical methods, which are usually valid for billets and thick plates, have given considerable error in the results. The proposed approach is applied to study the effect of thickness reduction ratio, coefficient of friction, work roll diameter and front and back tensions on the roll force, rolling torque and forward slip in thin hot strip rolling. The main merit of the proposed analytical approach, as compared to finite element simulation, lies in the drastic reduction in the computational time required in finite element simulation, which favours its use in online control of rolling thin strips.