Rock Crushing Rule of Thumb Mineral Processing & Metallurgy
· Impact crushers rotary or hammer mills have the capacity for high reduction ratios up to 40 1 but are rarely applied to hard rock mines Since they depend on high velocities for crushing wear is greater than for jaw or gyratory crushers Hence they should not be used in hard rock mines that normally have ores containing more than 15% silica or any ores that are abrasive Source Barry