Predicting rolling behaviour

Abstract

The assumptions which form the foundation of a classical cold-rolling theory are considered in the light of the use to which a theory is put, and it is concluded that differences between ferrous and non-ferrous metals do not appear to warrant variations in models. Reliable methods of calculating roll separating force and torque exist which are useful for design and scheduling purposes and which are applicable to a wide variety of rolling conditions, but there is a continuing need for accurate data on the appropriate values of yield stress and the coefficient of friction. However, because of the numbers of variables and the rapidity with which the variables change during rolling, a classical theory has not been, and is unlikely to be, devised which is adequate for continuous control. Finally, some questions are asked which, it is hoped, will promote discussion and assist the rolling industry as a whole to concentrate on those theoretical and practical problems the solving of which will lead to greater profitability.