Estimate Mill Steel OR Rock Charge Volume

Estimate Mill Steel OR Rock Charge Volume

This is a 2nd Method for estimation or measuring the steel charge volume inside a mill. If dealing with a full SAG/AG mill, this will give you the rock load%.  If you can count liners, you’ll have your answer.

The 1st method uses similar parameters.


Find more at

count liner rows in mill to estimate ball charge level

Effect of Mill Filling on the Energy Input

The effect of mill filling on the energy input is studied by varying the number of discs. Figure 6 shows the variation of torque with mill filling. Mill filling is calculated based on the fraction of the total area occupied by the discs. As expected, the energy input reaches a maximum and then falls off. This simulation was done with 2-cm diameter discs, and the mill speed was kept at 62% of the critical speed.

ball-mill variation of torque

ball mill variation of torque with mill filling