Chatter prevention in stands of continuous cold rolling mills

Abstract

The article states new results of the theoretical and applied research on prevention of chatter in stands of continuous cold rolling mills. It was found that chatter occurs under those process conditions, which involve violation of a condition of strip rolling with tension because of ongoing change of the process state, when the process proceeds now with tension and now with pushing because of variation of strip volumes per second in a negative or positive range of values. It is demonstrated that it is possible to influence effectively the difference of strip volumes per second and prevent chatter by decreasing reduction in a stand subject to chattering and simultaneously increasing reduction in adjacent stands, and also by changing the ratio of rolling speeds in these stands of the mill. This has led to development of process conditions for thin steel strip rolling on the 5-stand mill 1700 of PAO Severstal, enabling rolling speed increase and process stabilization.

Keywords

• steel strip
• cold rolling
• chatter prevention
• continuous mill stand
• rolling mode