We have types of ball mill for sale. The ball mill machines mainly include raw mill, coal ball mill, ore ball mill, small ball mill, wet ball mill, ceramic ball mill, overflow ball mill, as well as vertical ball mill, rod mill and automatic semi-automatic mill and other industrial milling equipment.188.8.131.52 Ball Milling. A ball mill is a type of grinder used to grind and blend bulk material into QDs nanosize using different sized balls. The working principle is simple impact and attrition size reduction take place as the ball drops from near the top of a rotating hollow cylindrical shell. The nanostructure size can be varied by varying.