The main working part of the ball mill grinding material occurs on the horizontal low-speed rotating cylinder. When the material is subjected to impact crushing and grinding and grinding, the material height of the material feeding end and the discharging end is different, so that the material is fed. The end is slowly flowing to the discharge end to complete the grinding operation. When the cylinder is driven to rotate by the transmission device, the grinding body is attached to the lining surface of the inner wall of the mill cylinder by the action of the inertia centrifugal force, and is rotated together with the belt, and is brought to a certain height and then freely dropped by gravity. At this time, the grinding body crushes the material in the cylinder, and at the same time, in addition to the rising and falling cyclic motion in the rotating mill, the grinding body also generates sliding and rolling, which causes the grinding body, the lining plate and the material to be ground to occur. Grinding causes the material to be fine.
Obviously, in the normal operation of the mill, the motion state of the grinding body has a great influence on the abrasive effect of the material. Can be brought to a higher level by the mill, like a projectile falling grinding body because of its high kinetic energy, so the material has a strong impact crushing capacity, can not be brought to the height of the mill, and the material under the slide, the material has a strong grinding capacity. The movement state of grinding body in mill is usually related to the speed of mill, the amount of RAM and the quality of grinding body. When the barrel has different rotational speed, the grinding body will appear 3 kinds of motion state:
1. When the rotation speed of the cylinder is moderate, the grinding body is lifted to a certain height and then thrown down, showing a "falling motion state". At this time, the grinding body has a large impact and grinding effect on the material, and the grinding effect is better.
2. When the rotation speed of the cylinder is too low, the grinding body can not be brought to a higher height, and the grinding body and the material will then fall due to the action of gravity, showing a "dumping motion state", and the impact on the material is small, almost only Grinding action, resulting in poor grinding results and reduced productivity.
3. When the rotation speed of the cylinder is too high, since the inertial centrifugal force is larger than the gravity of the grinding body itself, the grinding body and the material are attached to the inner wall of the cylinder, and rotate with the cylinder without falling, showing a "circular motion state". The abrasive body does not have any impact or abrasive action on the material.
In the ball mill barrel, the number of grinding body filling is less, the higher the cylinder speed, the more the rolling and sliding of the grinding body, the smaller the grinding effect on the material, the smaller the number of abrasive body filling, and the grinding body distributed near the center part of the barrel, which is not enough to form a ejection motion. And the production of more rolling and sliding, resulting in the grinding of materials and fine grinding. Therefore, in the grinding particle size larger or harder materials, the average size of the grinding body to be larger, the number of filling can be less, so as to ensure that the grinding body has enough ejection landing height, strengthen impact fragmentation. Conversely, in the grinding of smaller or more easily grinding materials, the average size of the grinding can be smaller, but the number of filling should be more, this will enhance the grinding effect.