The function of grinding ball mill liner
2020-04-03 10:19:06
Ball mill is important equipment in the ore beneficiation production line. Its grinding effect mainly depends on the rotary motion of the cylinder. The ball mill lining board is used to bring the stones to the high point for downward throwing motion. It impacts the ball mill lining board to achieve the function of crushing and grinding.
The material first enters the first silo of the mill with a stepped lining. The steel ball grinding bodies of different specifications in the cabin rotate with the cylinder. Due to the combined effects of inertia, centrifugal force and friction, the grinding body is attached to the lining and brought to the after falling at a certain height, the falling grinding body acts like a projectile on the material in the barrel. The material is crushed and ground. After rough grinding in the first warehouse, the material passes through the single-layer compartment board and enters the second warehouse with a flat liner. After further grinding, the powdery material is discharged through the discharge grate plate to complete the grinding operation.
The grinding parts are mainly composed of a cylinder, a hollow shaft for feeding and discharging, a grinding body and a grinding head. The cylinder is made of steel plate and fixed by steel lining plate; the grinding medium is steel ball, or rigid section can be used to load the cylinder according to different diameters and proportions.
The influence of the shape of the liner on the grinding efficiency of the ball mill was simulated and analyzed from three aspects of the ball mill’s media trajectory, useful power and collision energy distribution, and the following conclusions were drawn.
1. The shape of the liner has a great influence on the trajectory of the medium. The shape of the liner is a rectangular mill, the outer layer of the medium performs a dropping motion, and the inner layer of the medium performs a dropping motion; the mill in the shape of a trapezoidal plate has a large number of media in the dropping motion, and the height of the media in each layer is relatively high. Large; the shape of the liner is a wave mill, and there are many media in the drop state, but the drop height of a large number of inner media is very small.
2. At the same speed, the useful power of the mills with different liner shapes varies greatly. Under the premise of ensuring that the medium can effectively impact the medium area when the medium is lowered, the shape of the lining plate is rectangular, trapezoidal, and the wave ball mill has a rotation rate of 60%, 75%, and 90%, respectively.
3. The useful power difference of the mill is caused by the low energy collision (1-20J) at the appropriate speed. When the diameter of the material is small, low-energy collision can also cause the material to be broken. The grinding efficiency of the corrugated liner mill is large; when the diameter of the material is large, only high-energy collision can cause the material to be broken. Therefore, rectangular or trapezoidal linings with relatively low energy collisions should be selected.