CONTROL OF ROLL CONTOUR FOR STRIP PROFILE AND FLATNESS IN HOT ROLLING

摘要

Variation of roll contours affecting behavior of strip profile and flatness is a key factor in determining the configurations of mill type for hot strip mills. According to the investigated backup and work roll contour pattern, different mills, such as continuously variable crown (CVC), pair cross (PC) mill, varying contact rolling (VCR), work roll shifting (K-WRS) mill, are proposed to be appropriate for upstream and downstream stands for strip profile and flatness control. A rather smooth local work roll contour near strip edges and an increase in length rolled can be achieved by application of long stroke work roll shifting system, especially in downstream stands. The requisite crown can be obtained conveniently by application of varying contact backup rolls in the upstream stands that have almost the same roll contours during an entire hot strip mill cycle. And at the same time the crown control range by bending force and the roll gap stiffness with varying contact backup rolls are greater than that with conventional backup rolls in hot finishing mills.