... bauxite, manganese ore, iron mine, copper, phosphate ore, etc, which is harder than seven degree ... .Fourth: important part adopt high quality steel, abrasion proof adopt high quality abrasion material, the whole machine ... maintance, etc.4.Technical parameter of Raymond Grinder Model3R21153R26153R27153R30164R3216RollerNumber33334Diameter (mm)210260270300320Height (mm)150150150160160RingInside diameter ...