Selection of grinding media balls for ball mills
Views: 636 Update Date:Apr 13 , 2022
During the use of the ball mill, the selection of grinding media is very important. Grinding media is affected by various factors such as material, filling amount, shape, particle size, etc. In the grinding process, different grinding media can be used for different materials, models, and equipment, which can reduce production costs and improve production efficiency.
Material
The grinding material determines the cost and efficiency of grinding. Grinding materials can be mainly divided into three categories: metal media, rock and mineral materials and non-metallic materials. In addition to considering the production cost, the selection should also consider whether the materials and media will cause pollution. Commonly used grinding media are steel balls, alumina balls, zirconia balls, etc.
Filling amount
The filling amount has a direct impact on the grinding efficiency, and the particle size of the grinding media determines the filling amount of the grinding media. It must be ensured that the porosity of the grinding media is not less than 40% when the grinding media moves in the disperser. For different fineness requirements, it is necessary to adjust the crushing and grinding capacity distribution of the grinding media. The higher the filling rate, the stronger the grinding ability, and the stronger the crushing ability.
Media density, hardness, size
The denser the grinding media, the shorter the grinding time. In order to increase the grinding effect, the hardness of the grinding media must be greater than that of the material to be ground. According to long-term experience, the Mohs hardness of the media is preferably more than 3 grades higher than that of the material to be ground. In addition, the smaller the grinding media size, the more media contact points and the more opportunities to grind the material.
Grinding media are generally spherical, because other irregularly shaped media will wear themselves and cause unnecessary pollution. The size of the media directly affects the grinding efficiency and product fineness. The larger the diameter, the larger the product particle size and the higher the output. On the contrary, the smaller the media particle size, the smaller the product particle size and the lower the output. In actual production, it generally depends on the feed particle size and the required product fineness.
Media ratio
Generally speaking, in the continuous grinding process, the size of the grinding media is distributed regularly, and the ratio of the media size is directly related to whether the grinding capacity can be exerted and how to reduce the media wear. It will always maintain a fixed media ratio. In production, the method of supplementing large balls is often used to restore the grinding of the system. It is difficult for the mill to maintain a fixed media ratio for a long time. When the diameter of the media is too different, it will aggravate the ineffective grinding between the media and increase the cost of the grinding process; it is necessary to explore the appropriate ratio according to the type of material and process characteristics in the production process, and remove the media that is too small in time to reduce the cost.
Abrasion resistance and chemical stability
Prev: Application areas and technical standard of grinding steel ball
Next: Grinding media ball determines the grinding effect
Material
The grinding material determines the cost and efficiency of grinding. Grinding materials can be mainly divided into three categories: metal media, rock and mineral materials and non-metallic materials. In addition to considering the production cost, the selection should also consider whether the materials and media will cause pollution. Commonly used grinding media are steel balls, alumina balls, zirconia balls, etc.
Filling amount
The filling amount has a direct impact on the grinding efficiency, and the particle size of the grinding media determines the filling amount of the grinding media. It must be ensured that the porosity of the grinding media is not less than 40% when the grinding media moves in the disperser. For different fineness requirements, it is necessary to adjust the crushing and grinding capacity distribution of the grinding media. The higher the filling rate, the stronger the grinding ability, and the stronger the crushing ability.
Media density, hardness, size
The denser the grinding media, the shorter the grinding time. In order to increase the grinding effect, the hardness of the grinding media must be greater than that of the material to be ground. According to long-term experience, the Mohs hardness of the media is preferably more than 3 grades higher than that of the material to be ground. In addition, the smaller the grinding media size, the more media contact points and the more opportunities to grind the material.
Grinding media are generally spherical, because other irregularly shaped media will wear themselves and cause unnecessary pollution. The size of the media directly affects the grinding efficiency and product fineness. The larger the diameter, the larger the product particle size and the higher the output. On the contrary, the smaller the media particle size, the smaller the product particle size and the lower the output. In actual production, it generally depends on the feed particle size and the required product fineness.
Media ratio
Generally speaking, in the continuous grinding process, the size of the grinding media is distributed regularly, and the ratio of the media size is directly related to whether the grinding capacity can be exerted and how to reduce the media wear. It will always maintain a fixed media ratio. In production, the method of supplementing large balls is often used to restore the grinding of the system. It is difficult for the mill to maintain a fixed media ratio for a long time. When the diameter of the media is too different, it will aggravate the ineffective grinding between the media and increase the cost of the grinding process; it is necessary to explore the appropriate ratio according to the type of material and process characteristics in the production process, and remove the media that is too small in time to reduce the cost.
Abrasion resistance and chemical stability
Abrasion resistance and chemical stability of grinding media is an important condition for measuring the quality of grinding media. Non-abrasive media needs to be supplemented due to wear, which will not only increase costs, but more importantly, affect production. The grinding media needs to have a certain chemical stability in the specific grinding process, and cannot chemically react with the material during grinding, causing pollution to the material.
