The most important equipment in various mineral processing plants is the ball mill, which is used for grinding lime, gypsum, sand, slag and other materials. Only after the materials are ground to the required fineness can they be fully mixed and interacted. How to effectively improve the grinding fineness is one of the important links in the whole mineral processing operation, because the cost of grinding operation is a higher part of the mineral processing plant. How to effectively and reasonably control the grinding fineness is an important factor in directly reducing the cost of mineral processing and improving the economic benefits of the mineral processing plant. Grinding fineness is one of the many factors that affect mineral processing indicators. The size of grinding fineness directly affects the grade of concentrate and the recovery rate of products.

The size of the feed particle size of the ball mill has a great influence on the productivity and energy consumption of the mill. Under the specified grinding fineness, the finer the feed particle size, the higher the production capacity of the mill, and the lower the energy consumption of processing unit ore. However, in the ore dressing plant, the feed of the grinding operation is the final product of the crushing operation. Reducing the feed size of the grinding machine means that the crushing operation has to produce finer products, which will inevitably increase the total crushing ratio of the crushing operation, make the process more complicated, and increase the cost. On the contrary, if the feed size is increased, the cost of crushing will be lower, but the cost of grinding will increase. Therefore, when determining the feed size of the grinding machine, comprehensive consideration should be given to keep the total cost of crushing and grinding low.

Usually, when determining the appropriate feed size of the ball mill, the scale of the ore dressing plant is mainly considered, and the performance of the equipment used in the crushing operation and the type of crushing process are also considered. Since in the conventional crushing and grinding process, the energy consumption of crushing is small while the energy consumption of grinding is high, and the efficiency of crushing is higher than that of grinding, therefore, in production, when conditions permit, the ball mill should be provided with fine feed materials as much as possible to give full play to the role of crushing to improve the processing capacity of the ball mill, which is the so-called "more crushing and less grinding".