Tumbling ball mills or ball mills are most widely used in both wet and dry systems, in batch and continuous operations, and on small and large scales. Grinding elements in ball mills travel at different velocities. Therefore, collision force, direction, and kinetic energy between two or more elements vary greatly within the ball charge.
A section cut thru of ball mills A ball mill is a type of grinder used to grind or blend materials for use in mineral dressing processes, paints, pyrotechnics, ceramics, and selective laser sintering. It works on the principle of impact and attrition: size reduction is done by impact as the balls drop from near the top of the shell.
A ball mill also known as pebble mill or tumbling mill is a milling machine that consists of a hallow cylinder containing balls; mounted on a metallic frame such that it can be rotated along its longitudinal axis. The balls which could be of different diameter occupy 30 50 % of the mill volume and its size depends on the feed and mill size.
The ball mill accepts the SAG or AG mill product. Ball mills give a controlled final grind and produce flotation feed of a uniform size. Ball mills tumble iron or steel balls with the ore. The balls are initially 510 cm diameter but gradually wear away as grinding of the ore proceeds.
Ball mill operation is often regarded as something of a mystery for several reasons. Ball milling is not an art its just physics. The first problem will ball mills is that we cannot see what is occurring in the mill. The other problem is that many of the independent variables are non linear or have paradoxical effects on the end results.