The material is uniformly fed into the first bowl of the cement ball mill by the feeding device through the hollow shaft. The first hopper has a stepped or corrugated liner, which is filled with steel balls of different specifications. The rotation of the cylinder generates a centrifugal force to bring the steel ball to a certain height, and the balls falling downward will hit and grind the material. After the material reaches coarse grinding in the first container, it enters the second container through the single-layer transfer partition. The second silo has a flat lining with steel balls inside to continue grinding the material. The powder is discharged through the discharge grille.