Ball mill media ball loading and ball size and matching principle

- May 05, 2018-

For the effect of the ball mill, the load of the ball mill media is very important and requires strict control. The load of the ball mill medium mainly includes the amount of ball loading and the size and proportion of the ball. What are the basic requirements to be met?


The first is the calculation of the amount of ball loading on the ball mill media, that is, the percentage of the volume of the grinding media in the effective volume of the mill. We also call it the grinding media filling rate. The ball filling rate of the ball mill directly affects the number of impacts during the grinding process, the grinding area and the loading of the grinding media. At the same time, it also affects the height of the grinding media itself, the impact on the material, and the power consumption.


Under normal circumstances, the ball loading of the ball mill media is calculated according to the corresponding formula, the formula is G = Vρψ, in fact, G is the load of the grinding medium; Ρ is the loose density of the grinding medium; Ψ is the grinding medium filling rate.


When wet grinding, the ball load of the lattice ball mill medium is 40% to 45%, overflow ball mill is 40%, and rod mill is 35%. When the material is mixed into the grinding medium during dry grinding, the grinding medium expands, and when the dry method is used, the material flow ability is poor, and the material flow is hindered by the grinding medium, so the filling rate is selected to be low, and the rate is 28%-35%. Between the tube mill and 25%-35%.


Secondly, the size and ratio of ball mill media must also be controlled reasonably. It has a great influence on the productivity and working efficiency of the ball mill. For coarse and hard materials, larger steel balls should be used; fine and crisp Material, with smaller diameter steel balls.


The number of impacts of the ball mill media in the mill increases with the decrease of the ball diameter. The grinding gap between the ball and the ball is dense with the decrease of the ball diameter. Therefore, the ball with larger mass and smaller diameter should be used. For grinding media. The size of the ball depends mainly on the particle size of the material to be milled, and secondarily the diameter and speed of the mill can be appropriately considered.


After obtaining the diameter of the steel ball, the proportion of the steel ball in the mill can be determined by referring to the curve of the media of the ball of the ball mill. According to the process requirements, material properties, mill specifications and various parameters, after selecting the large diameter and small diameter of the steel ball, and then matching the ratio level, using the curve, check the corresponding steel ball into the mill. Accumulation of the percentage of the mass, calculate the actual mass percentage, so as to obtain the loading quality of all levels of steel balls.