Differences Between Ball Mill and Rod Mill

Ball mill and rod mill are quite similar whether in external shape or working principle. So what are the differences between ball mill and rod mill? Xinhai mineral processing equipment specialist explains it as follows:

Both ball mill and rod mill have cylinder. Two ends are covered up. There is a neck of hollow shaft on the cover, and the cylinder is rotated in the bearing of shaft neck.

Firstly, the two have in common is that both are cylinder grinding equipment. When the cylinder is rotating, the cylinder rotates with the materials fed from the cylinder inlet and crushed by the falling impacts and autogenous grinding of the steel balls and ores in the cylinder. Due to the continuously feeding materials, the pressure pushes materials to the outlet and the grinded materials are discharged from the cylinder outlet. Qualified materials flow from the cylinder outlet. In wet grinding, the materials are taken out by the water flow.

Ball mill and rod mill are usually driven by asynchronous motor or synchronous motor. The rotating speed of cylinder is below the critical speed. In order to obtain better impact effect, some ball mill speed can be adjusted. Ball mill and rod mill are used in wet and dry process to deal with various hardness of ore, rock and other materials.

So what are the differences between ball mill and rod mill?

1. Ball mill and rod mill are used to deal with various hardness of ore, rock and other materials whose particle size is not more than 60mm. The particle size range is 1.5mm and 1.5mm after treated with ball mill, otherwise the particle size range is below 6mm and 6mm after treated with rod mill.

2. Ball mill and rod mill are distinguished according to different medium. The grinding medium of ball mill is steel ball, otherwise the grinding medium of rod mill is steel bar. The steel bar can contact with mineral surface directly when falling, which has a selective grinding effect, namely grinding the ore according to the size from large to small, the grinding mineral particle size is evener. Therefore, rod mill is often applied in coarse grinding or gravity separation plant that requires light overgrinding.

In the end, Xinhai mineral processing equipment specialist summarizes that ball mill and rod mill have roughly same principle and structure. The main difference is that the grinding medium of ball mill is steel ball, and the grinding medium of rod mill is steel bar. Besides, the particle size of grinding product is also different.