Idler Flange Rolls
Circumferential differences between the throat diameter and the outer flange diameters translates into surface speed differences that can cause skidding and scuffing of the strip near the outer diameter of the roll. Galling or "pick-up" then occurs. The solution is to separate the root or drive area of the roll from the flange's forming surface. The flange is then mounted on bearings so it can idle or in effect turn at the same speed as the strip and little or no skidding occurs in this area.
This design option is most frequently used on driven breakdown rolls but can also be applied to fin passes and sizing rolls and in extreme cases, idler rolls. When the ratio between the lowest and highest contact points between the roll and the scalp approaches 2:1, this problem is imminent.
A JMC Rolls our representative is always available to discuss with you the various bearing and mounting options for this application.