ABSTRACT
From the viewpoint of mill operation and design, the prediction of spindle torques is of the same importance as the prediction of rolling force. In 1948 Hill proposed a model relating specific spindle torque to other rolling parameters. By consideration of various artificial distributions of pressure along the arc of contact, he showed that the ratio of the specific rolling force to the specific spindle torque depends only slightly on the precise shape of the friction hill. The electric power input to the main mill motor, the rolling speed and the reduction are noted for the various passes. The energy requirement in terms of horsepower-hours per ton of material rolled is then calculated for each pass and a chart is prepared in which the total horsepower-hours per ton up to and including that pass are plotted against the total elongation at the end of the pass.
