Rod mill machines and ball mill machines are commonly used in grinding equipment. Many users don't know how to choose these two types. Here, Jiangxi Changyi Mining Machinery Co., Ltd. will tell you how to choose ore grinding equipment, so continue to know how to choose suitable grinding equipment?
Idea 1: according to the nature of the selected ore
1. hardness characteristics: Rod mill is suitable for ores with Mohs hardness of 5.5-12. Generally suitable for grinding brittle materials. For example, rod mills are commonly used in gravity separation or magnetic separation of rare metals such as tungsten ore and tin ore. Ball mill has strong adaptability to materials and is suitable for grinding hard materials, such as lime and slag.
2. Grain size characteristics: The medium inside the rod mill is a high carbon steel rod with a carbon content of 0.8%-1% and a diameter of 50-100 mm. The inner surface of the end cover liner is a vertical plane, which ensures the regular movement of the steel bar. In the grinding operation, the steel rod is thrown up under the centrifugal force, and after falling horizontally, it comes into surface-line contact with the ore material. Most coarse particles are ground first, and a small part of fine particles are ground. Therefore, the rod mill product is rough, with uniform texture and good grain shape, which is not easy to produce over-grinding phenomenon, and the qualified rate of finished products is high.
Ball mills use steel balls as grinding medium. Because the steel ball is in point contact with the mineral aggregate, the crushed product has high fineness and fine particle size, which is prone to over-crushing and is not suitable for the gravity separation production line in metal beneficiation.
Select suggestions:
Fine grinding stage: when the particle size of the product is less than 0.5 mm, it is recommended to use a ball mill (the feeding particle size of the ball mill is generally 5-25 mm).
Coarse grinding stage: when the granularity of the product is required to be 1-3 mm, it is recommended to use a rod mill (the feeding granularity of the rod mill is generally 15-23 mm).
Idea 2: choose according to the characteristics of the mill equipment.
Mill profile In the design of concentrator, it is usually necessary to design the layout of grinding workshop in advance, so it is necessary to consider the shape of the equipment. The barrel shape of rod mill and the ball mill is different: the barrel of rod mill is long, and the ratio of length to diameter is generally 1.5-2.0; The barrel of the ball mill is cylindrical or conical, and the ratio of length to diameter of the barrel is small, and in most cases, the ratio is only slightly larger than 1. Therefore, whether the equipment installation conditions can be met should be considered when selecting.
