The grinding effect of ball mill is accomplished by the steel ball, and the strength of the grinding action is determined by how much the steel ball is filled in the mill. From the physical phenomenon, the ball is more, the number of blows, the grinding area is large, the grinding effect is strong, on the contrary, the number of ball-loading is less, the grinding area is small, the grinding effect is weak. The Mechanics phenomenon analysis, the load ball consumes the work to be big, the mill productivity is also big, the ball load is small, the mill productivity is also low.

Since the filling rate of spherical charge and the rotary rate of the mill work together, it is not possible to lose the turning rate when analyzing the effect of filling rate. When the mill is at a lower rotational speed, the ball charge forms a tilted surface in the mill, the ball rises to the high point and rolls down along the ball-load incline, forming the Rorippa movement State. With the increase of the filling rate of the ball charge, the angle of the ball-load inclined surface increases, the ball-load sliding moment increases, the grinding machine needs to work more, according to Davis and Levinson and other people's theory, the ball filling rate reaches 50% when the mill power reaches maximum value, as shown in Figure 1 When the filling rate exceeds 50%, the mill power begins to decline, because the ball load rises too high, the ball falls back to the point when rolling down, and the energy is returned to the cylinder, so the actual need of the mill power drops. When the filling rate of the ball is 100%, the speed grinding machine actually becomes a roller, the mill only needs to maintain the energy of the drum rotation, so the power of the mill is very low. If the mill is fitted with ore and water, the actual curve of the mill power is different from the theoretical curve, and the filling rate is shifted down to the maximum power, which is due to the increase of the actual filling rate of the spherical charge.