In addition, the contact mode between media and materials and between media also has a great influence. Although spherical medium is widely used in China, because its crushing mode is mostly point contact and the crushing force is large, it is also easy to lead to over crushing.
The rolling property of cylindrical medium is slightly worse than that of steel ball, but due to line contact, there is less over crushing. Therefore, it is suitable for coarse grinding rather than fine grinding.
Vertical roller mill lining plate is mainly used to protect the cylinder and avoid damage to the cylinder caused by direct impact and friction of media and materials. Because of its long-term contact with media and materials, it is easy to be damaged.