Vibration characteristics of an operating ball mill

Abstract

A ball mill, which is used to finely grind materials, causes high levels of vibration and sound during grinding operations. The vibration and sound of mills provide significant information about the internal conditions and can be used to estimate the status of the ground material. We developed a simulation model for the vibration of a mill wall to better understand the relationship between the operating conditions and wall vibration characteristics. The discrete element method can be used to predict the motion of the contents, which are grinding balls and material particles, and estimate the collision force between the balls and the mill wall. A finite element method vibration analysis is performed to calculate the time history response of the vibration from the estimated collision force by DEM. Simulations and experiments are performed to evaluate the influence of changing material particle diameter on the vibration characteristics. The results of experiments and simulations show the same tendencies. A decrease in material diameter reduces the vibration velocity of the mill. The developed simulation is useful for understanding the vibration characteristics of the mill because it could obtain information, such as individual particle element velocities, that is not available from the experiments.