A ball mill is a type of crushing machinery, classified into crushing machinery and grinding machinery based on the size of the feed particles. Ball mills are a commonly used type of crushing machinery. The development of crushing machinery actually has a long history. A ball mill is a key equipment used after the material has been crushed for further grinding. It is widely used in the cement, silicate products, new building materials, refractory materials, non-ferrous metal ore selection, and glass ceramics industries, for dry or wet grinding of various ores and other grindable materials.
Ball Mill Working Principle
The ball mill consists of a horizontal cylinder, hollow shafts for feeding and discharging materials, and grinding heads. The cylinder is a long cylindrical shell, containing grinding media, which are typically steel balls. These balls are loaded into the cylinder in varying diameters and proportions. Alternatively, steel segments can be used, depending on the particle size of the material being ground. Materials are fed into the cylinder through the hollow shaft at the feeding end. As the ball mill cylinder rotates, the grinding media, due to inertia, centrifugal force, and friction, adhere to the cylinder's lining plates and are carried along. When they reach a certain height, gravity causes them to be thrown down, smashing the material inside the cylinder like projectiles.
During the rotation, the grinding media also exhibit a falling phenomenon, exerting a grinding effect on the material during the fall. To effectively utilize the grinding effect, when the material particle size is generally reduced to 20 mesh, the mill cylinder is separated into two sections by a partition plate, forming a double-compartment mill. When the material enters the first compartment, it is crushed by steel balls. Upon entering the second compartment, the steel ends grind the material. The finely ground material is discharged from the hollow shaft at the discharge end. For materials with smaller feed particles, such as sand slag No. 2 and coarse fly ash, the mill cylinder may not be equipped with a partition, becoming a single-compartment cylinder mill. The grinding volume can also be used with steel sections.
