Working Principle of Conventional Ball Mill

Date: 11/11/2012 7:32:09 PM

The grinding effects of ball mill mainly rely on the impact and grinding of body to materials. The motion of ball mill body inside the mill tube contains several different forms such as upward movement, downward movement and projectile motion. In order to further learn the movement rule of ball mill body, when we research the above problems, the following supposes are brought up.

Ball Mill

1. When the ball mill operates at normal speed, ball mill body will move circularly according to its location inside the mill tube.

2. There are two kinds of movement paths in mill tube for ball mill: one is the ball mill moves upward along with the barrel according to the track of concentric arcs. The other is that the ball mill falls according to the track of parabola.
3. Because the slide among ball mill body, supporting wall and ball mill is extremely small, it can be ignored when specific calculation is conducted.
4. The effects of materials inside mill tube to ball mill can be ignored.

The rotating speed and block coefficient of ball mill body plays a big role in grinding effects. When the rotating speed and block coefficient of ball mill body are different, the movement states of ball mill can be divided into two conditions:

1. Falling aslant type

When the rotating speed of barrel is too low and the ball mill body is too little, there is no impact effects except for rolling and slide function. Consequently, grinding efficiency is unsound.
2. Free fall type
When the rotating speed of barrel is appropriate, under the effects of centrifugal effect, ball mill body attaching on the inner wall of barrel moves upward with the barrel and is brought to the proper height, and then falls down like projectile. The materials are crushed by the huge impact effects. Additionally, the rolling and slide function also play grinding role in material grinding process.