Ball Mills - 911 MetallurgistDec 23, 2017 . Where the finished product does not have to be uniform, a ball mill may be operated in open circuit, but where the finished product must be uniform it is . mills (listed as being the same size) is due to the fact that there is no uniform method of designating the size of a mill, for example: a 5′ x 5′ Ball Mill.ball mill x what can it do,MBMM Ball Mills - Variable Sized Material Reduction EquipmentThe capacity, or throughput, of a ball mill, is directly linked to particle size of the ball mill discharge. For example, it takes approximately 3 times as long to achieve 200 mesh grind as it does to achieve 65 mesh grind. Establishing a commercial liberation size is critical when designing and engineering your grinding circuit.