Research on Wear of Grading Steel Balls by Discrete Element Method

Abstract

In this paper, the factors of steel balls' wear were studied by Discrete Element Method (DEM). Firstly models of steel balls' motion were established by Particle Flow Code in 3 Dimensions (PFC 3D) according to experimental condition. Then the motion regions of steel balls were simplified into grinding regions and throwing regions based on characteristics of steel balls' motion, then the quantity of steel balls in the two regions were counted. Void rate in grinding region and quality of steel balls in throwing region were calculated by data processing, and they were used respectively as criterion of grinding wear and impact wear of steel balls. The influence laws of grading scheme, rotary speed rate of mill and ball filling rate on void rate and throwing balls' quality were studied. The results showed that void rate and throwing balls' quality of three grading scheme had the same tendencies that was Grading>;Grading>;Gradingó when ball filling rate and rotary speed rate of mill were constant. Void rate and throwing balls' quality both increased firstly, then decreased with the rising rotary speed rate of mill at the same ball filling rate and grading scheme. When rotary speed rate of mill remained unchanged, void rate decreased but throwing balls' quality increased with ball filling rate increasing.