Simplified Weighted Velocity Field for Prediction of Hot Strip Rolling Force by Taking into Account Flatening of Rolls

The weighted velocity field was simplified for analysis of hot strip roling. Using the field and GM (geometric midline) yield criterion, the deformation power, friction power and shear power were obtained respectively. Summing the partial power contributions, the total deformation power for strip roling was presented. Then, by minimizing the power function, the roling force was obtained; meanwhile, considering the efect of rol elastic flattening, iterative calculation of the rol radius was carried out until the radius was convergent. On-line data were compared with the calculated results to verify the model accuracy. It was indicated that the calculated roling forces were basicaly in agreement with the measured ones since the maximumerror was less than 10? 0%. Moreover, the efects of various roling conditions such as thickness reduction, friction factor and shape factor, upon separating force, location of neutral angle, and stress state coeficient were discussed systematicaly.