A Model for Prediction of Roll Force and Torque in Edge Rolling

Abstract

Although edge rolling has been important since the early days of rolling, not until lately, methods for calculation of roll force and torque in edge rolling have been developed. Based on a simple upper bound solution, including plastic flow perpendicular to the rolling direction, a model was derived and arranged to be possible to implement into commercial roll pass design and set up software. Verifications were made in a laboratory rolling mill. Heavy strain hardened copper, and precipitation hardened aluminium were rolled. The calculated forces were in good agreement with the measurements. The developed model has been examined from well documented industrial rolling trials. The relation between the predicted and measured forces, are within 10 % and only in one case of twenty the predicted force deviate more than 15 % from the measured value. No trend indicating different precision as a function of the geometrical conditions has been seen. The experimental scatter is caused by the experimental situation rather than error in the model, which still can be assumed to be in the order of the numerical approximations. The mathematical form of the model is sound, and better predictions of the roll force can be done with the new model compared to older models. By implementation of the new model into any commercial software for rolling analysis, all kinds of roll pass sequences for wire rod and bar rolling can be studied.