For this reason, LAVAL LAB offers a wide selection of high-performance mills, in various product groups, for every application and every specific need Planetary Ball Mills, Ball Mills, Cutting and Beater Mills, Rotor Mills, Jaw Crushers, Roll Crushers, Cone Crushers, Disk Mills and Mortar Grinders.For example, a single-roll crusher, employ shear together with impact and compression. Shear crushing is normally used under following conditions. When material is somewhat friable and has relatively low silica content. For primary crushing with a reduction ratio of 6 to 1. When a relatively coarse product is desired, top size usually larger.