Development of a Rolling Chatter Model Considering Unsteady Lubrication

Chatter, limiting the rolling speed for thin steel strips, has been identified as a serious limitation in increasing the efficiency of the cold rolling process. Many experimental investigations have led to the point that lubrication is one of the effective factors causing chatter. In this article, a new chatter model of the cold strip rolling with consideration of unsteady lubrication is proposed. The limiting shear stress concept and the variation of the lubricant viscosity with pressure are considered in this model. The results of the simulation are verified by comparing to experimental data. Also, a parametric study on the effect of some of the major parameters of rolling lubricant on the chatter critical speed is conducted. The results show that under the operating conditions of this paper, the limiting shear stress is an effective parameter.