Generally, the grading range is 25% ~ 35%, but the intermediate grading in practical application is mostly 28% ~ 32%. LM vertical roller mill steel ball grade ratio under common economic operation: steel ball diameter mm Φ one hundred Φ eighty Φ sixty Φ forty Φ 20 mass / total filling quantity 7.5% 6.9% 33.5% 30.1% 22 note: when the grindability of materials is poor or the grinding requirements are fine, the filling rate of one bin shall be & gt; 28%。

The temperature of LM vertical roller mill grinding material is too high. Generally, when the temperature of LM vertical roller mill grinding material is too high, it is easy to reduce the grinding efficiency. When the temperature of LM vertical roller mill exceeds 100 ℃, an air film isolated from each other on the surface of small particles of the material will be damaged, resulting in adhesion.

In order to reduce the temperature in the mill and improve the milling efficiency, a small amount of mist water can be sprayed into the milling bin to reduce the temperature in the mill to below 50 ℃.