1. Differences in scope of use:
Compared with ball mills, rod mills adopt advanced controllable feeding and discharging technology, and can use appropriate grinding bodies according to the grinding materials. The point contact of traditional ball mills is changed to line contact, which can make the discharge particle size more uniform and the output higher. high. Rod mill is mainly used for gravity separation or magnetic separation of tungsten tin ore and other rare metal ores, because the use of rod mill grinding can prevent dust pollution caused by excessive crushing and improve the recovery rate of sorting operations. Ball mills are suitable for grinding various ores and other materials, and are widely used in mineral processing, building materials and chemical industries. In addition, both can dry and wet grind materials.
2. Differences in grinding media:
Rod mills commonly use steel rods with a diameter of 50-100mm as the grinding medium, while ball mills use steel balls as the grinding medium.
The length of the steel rod is 25-50mm shorter than the cylinder, and is often made of high-carbon steel with a carbon content of 0.8%-1%; the loading amount of the rod is approximately 35%-45% of the effective volume of the rod mill. When observed with the naked eye, The horizontal plane of the rod is about 100-200m below the center line of the cylinder.
3. The difference in the ratio of cylinder length to diameter:
The ratio of the length and diameter of the rod mill barrel is generally 1.5-2.0, and the inner surface of the liner on the end cover should be a vertical plane. Its purpose is to prevent and reduce chaotic movement, bending and breaking of the steel rod in the barrel. Ensure that the steel rod moves regularly.
The ratio of the barrel length and diameter of the ball mill is small, and in most cases the ratio is only slightly greater than 1.
4. The fineness of finished products is different:
If the degree of refinement of the material is analyzed, the surface area of the steel rod medium volume in the rod mill is smaller than that of the steel ball medium in the ball mill, so the utilization coefficient is lower compared with the ball mill of the same size, and the rod mill is not suitable for fine crushing. Because of the characteristics of the rod mill, it is generally used for coarse grinding operations. In some materials, the rod mill can replace the fine crusher and solve the problem that the discharge port of the fine crusher is easily blocked.
5. Differences in ore discharge methods:
The rod mill does not use a grid plate to discharge the ore, but uses an overflow type and an open type to discharge the ore; the diameter of the hollow journal at the ore discharge end is generally larger than that of a ball mill of the same specification.
The speed of the rod mill cylinder should be lower than the working speed of the ball mill of the same specification, so that the medium in the rod mill works in a cascading state.
The above is about the difference between ball mill and rod mill. I hope it will be helpful to you!