#### TECHNICAL NOTES 8 GRINDING R. P. King - …

charge). Additional power is required to keep the mill rotating. 8.1.3 Power drawn by ball, semi-autogenous and autogenous mills A simplified picture of the mill load is shown in Figure 8.3 Ad this can be used to establish the essential features of a model for mill power. The torque required to turn the mill is given by Torque T Mcgdc T f (8.9)