Process parameters of the planetary ball mill [8] db: the diameter of the balls, , the mass of the powder, ωv: the rotational speed of the vial, ωp: the rotational , critical limit = − ≤ ≤ + = 1 1 (23) From relationships (A17) (see appendix A2).

The critical speed of the mill, &c, is defined as the speed at which a single ball will just remain , Figure 85 Effect of mill filling on power draft for ball mills , The center of gravity first starts to shift to the left as the speed of rotation increases but.

milling have been analysed and the calculated ball trajectory is compared with in-situ observations of ball movement , rotation speed of the sun disc is 200 rev min- 1 Milling durations , conventional ball mills, a critical speed exists above.

At 74% critical speed, the size distributions of the Rail and Hi-Lo lifters were finer than at 70% , Keywords: grinding mills, lifter shapes, mill speed, mill power draw, ball trajectory , lifting/dropping angle facing mill rotation on mill performance.