Development of an Estimation Method for Grinding State by Radiated Sound from a Ball Mill

Abstract

During grinding operations, ball mills emit high levels of vibration and sound. The vibration and sound relate to internal state and operation condition of mills. In this study, we develop a simulation model for operating ball mills to characterize the relationship between the internal states and the vibration and sound of the mill. The motion of the balls is calculated based on the discrete-element method. Simultaneously, collision force between the balls and the mill wall are calculated. The collision force is used as the input for a vibration analysis of the mill wall by the finite-element method. After that, assuming that there are many point sound sources on the surface of the mill, radiated sound is calculated from the vibration of the mill wall. The model can estimate the influence of operation condition on radiated sound and can clarify the relation between internal state and radiated sound.