One of the simplest roller mill is a pair of rollers of the same size, one fixed and the other adjustable. The two rollers rotate in the opposite direction at the same speed and the maximum diameter of the roller is 250mm.
The crushing degree of the roll crusher is relatively coarse, and only the well-dissolved malt is crushed with a roll, so that a satisfactory wort filtration rate and yield can be obtained. To this end, the crushing of the rolls must satisfy the following conditions: the malt feed is uniform and evenly scattered on the rollers. The feeding amount should be small. The feeding amount per centimeter roller length is 5-20 kg/h, and mal malabsorbed malt is also required to achieve the lowest quality standards. The crusher should be at a low speed of 160-180 r/min.
If the requirements for the crushed malt are high, or to crush the disintegrated malt, it is obviously necessary to repeat the comminution process of the rolls, thereby forming a four-roll mill or a multi-roll mill with two pairs of rolls facing up and down.