Ball mill is the principal equipment for smashing the material after it is crushed. It is widely used in cement, silicate products, new-type construction materials, refractory materials, glass, ceramics, non-ferrous metal dressing and other manufacturing industries. Ball mill can be used for dry or wet grinding all kinds of ores and other grindability materials. Description on the types of ball mill:
Ball mill can be divided into lattice ball mill and overflow ball mill.
(1) Short-type ball mill
The ball mill drum with length-diameter ratio below 2 can be called short-type ball mill. Generally, the single-cylinder short-type ball mills are used for the coarse or primary grinding process. Users can put 2~3 short-type ball mills in series and put them into production.
(2) Medium-length ball mill
If the length-diameter ratio of ball mill drum is at 3, this ball mill can be called medium-length ball mill.
(3) Long-type ball mill
If the length-diameter ratio of ball mill drum is more than 4, it's called long-type ball mill or tube mill.
Generally, the grinding cavity internal of medium-length ball mill and long-type ball mill is divided into 2~4 storehouse. They are widely used in cement plant.
(1) Ball mill
The grinding medium in ball mill is mainly the steel ball and the steel segment. Ball mill is the most commonly used mill.
(2) Rod mill
In rod mill, the steel rod with 50~110 mm diameter is used as the grinding medium. The length-diameter ratio of rod mill drum is often at 1.5~2.
(3) Rod and ball mill
This mill usually has 2~4 silos. Users can load the cylindrical steel rods into the first silo of rod and ball mill as the grinding medium, and then load the steel balls or steel segments into other silos. The length-diameter ratio of rod and ball mill drum should be around 5. The ratio between the length of rod bin and the effective diameter of the mill should be between 1.2 and 1.5. The rod length is about 100 mm shorter than the rod bin, so that steel rods can be arranged in parallel to prevent cross and collision.
(4) Gravel mill
The grinding medium of gravel mill cavity is gravel, pebble, porcelain ball, etc. The lining plate of gravel mill is made up the granite and porcelain materials. Gravel mill can be used to produce the white or colored cement and ceramic.
(1) Tail discharge ball mill
Material is fed from one end of the mill and discharged from the other end.
(2) Middle discharge ball mill
Material is fed by the two ends of the mill, then it is discharged from the middle of the mill drum. This mill is equivalent to two ball mills in parallel, it has compact structure so as to simplify the grinding process.
(1) Central transmission ball mill
The motor drives the ball mill to operate through the reducer drives the hollow shaft of unloading end. The shaft of the reducer is in line with the center line of the ball mill.
(2) Edge transmission ball mill
The motor drives the ball mill to turn by the reducer driving the big gear which is fixed on the unloading end of ball mill drum.
Ball mill can also be divided into intermittent ball mill and continuous ball mill. Compared with the intermittent ball mill, the continuous ball mill has higher mechanization degree and greater productivity. However, the infrastructure investment cost of continuous ball mill is larger and the maintenance is more complicated than that of intermittent ball mill. Intermittent ball mill are rarely used in industry, it is often used for the grinding test in laboratory now.