Roll Mills


 

Roll mills

2 rolls, one in adjustable bearings, rotate in opposite directions and the clearance between them can be adjusted according to the size of feed and the required size of product. Both rolls may be driven, or one directly and the other by friction with the solids. The crushing rolls, which may vary from a few cm up to about 1.2m in diameter, are suitable for effecting a small size reduction ratio, 4:1 in a single operation, and it is therefore common to employ a number of pairs of rolls in series, one above the other. The capacity is usually between one-tenth and one-third of that calculated on the assumption that a continuous ribbon of the material forms between the rolls.