Brush roll and its brush device

The present invention relates to brush rolls and brush elements therefor for use in grinding, polishing, cleaning or otherwise treating steel sheets, plates or strips (hereinafter referred to briefly as "steel plates") in the iron manufacturing industry, and more particularly to brush rolls of the type wherein a brush element fitted around a shaft comprises annular disks arranged side by side and each having polishing bristles or cleaning yarns implanted in the outer periphery thereof, and also to the brush element. A brush element U includes an assembly of annular disks joined together as arranged side by side. Each disk has polishing bristles or cleaning yarns implanted in its outer periphery. The brush elements U are arranged side by side around a shaft . The brush element U is engageable with the shaft by keyways formed in both a peripheral surface of the shaft and an inner peripheral surface of the brush element U and by sunk keys fitted in the respective keyways . The sunk keys have a length not larger than the length of the brush elements U, and each of the sunk keys is expandable or contractable widthwise and tightly engageable in the keyway when being expanded. The sunk key is disengageable therefrom when being contracted. The sunk key is prevented from slipping out of the keyway by a retainer C when being contracted and fitted in the keyway . The brush roll and brush elements thereof are useful for grinding, polishing cleaning or otherwise treating steel sheets, plates, or strips.