The structure and principle of the vertical mill
Source:cronus
Posted:2025-11-14 10:50:23
It is well known that the common processing methods for heavy calcium include dry and wet methods. The advantage of dry processing lies in its facilitation of achieving industrial scale and a certain degree of product refinement. The main dry process equipment includes Raymond mills, high-speed mechanical impact crushers, jet mills, ball mills, vibration mills, ring roller mills and vertical mills, etc. Among them, the vertical mill dry grinding method has the most obvious benefits of scale and refinement. The vertical mill + secondary/tertiary classification process technology has become the preferred technology for heavy calcium processing enterprises.
There are various types of vertical mills at home and abroad, but their structural principles are basically the same. They are mainly composed of drive devices, reduction devices, roller grinding systems, powder selection systems and auxiliary systems, etc. Among them, the grinding roller and grinding disc device are the main working components of the vertical mill.
The working principle of the vertical mill: The vertical mill uses the relative motion between the grinding roller and the grinding disc to crush the material in the material bed. As the pressure of the grinding roller increases, the fineness of the material decreases. The finely ground materials are lifted by the airflow and classified inside the mill by the classification device on top. The coarse powder falls into the grinding disc and is crushed again. Qualified fine powder is carried out by air and ground to the bag dust collector for collection.
Looking at the structure and working principle of vertical mills, the factors that affect their operation and running include the characteristics of the material entering the mill, the pressure difference of the mill, the ventilation volume of the system, and the working pressure of the grinding rollers, etc
The characteristics of the material entering the mill: mainly refer to the hardness, particle size, moisture content and grindability (Bond work index) of the material, etc.
Mill pressure difference: One of the important parameters reflecting the load condition of the material circulation inside the mill. It mainly consists of two parts: the local ventilation resistance at the air ring of the vertical mill and the resistance generated during the powder selection process of the powder separator.
The ventilation volume of the system: It is mainly regulated by the opening degree of the fan damper (or the variable frequency speed regulation of the fan motor). The leakage of air from the vertical mill body, dust collector and ventilation duct has a significant impact on the ventilation inside the mill and is often a factor causing a decrease in output and unstable operation.
The working pressure of the grinding roller: It needs to be reasonably set based on factors such as the feeding amount, the thickness of the material layer, and the fineness of the product.
The rotational speed of the classifier: Under the condition that the ventilation volume of the system is constant, the higher the rotor rotational speed, the higher the fineness of the material coming out of the mill. Conversely, when producing coarse powder, the rotor speed needs to be reduced.
Other factors: Height of the material retaining ring; Air ring clearance (area) Wear of grinding rollers and grinding discs.
Cronus CRLM series vertical grinding mill
Cronus vertical mill is a highly efficient and energy-saving drying and grinding equipment developed based on extensive absorption of advanced foreign technologies and years of practical experience. This equipment has been put into operation in industries such as cement, metallurgy, chemical engineering, non-metallic and non-ferrous metal ore grinding, and coal grinding in power plants. It is used for grinding raw materials of cement, cooked (slag) materials, coal, gypsum and mineral materials such as pyrophyllite, calcite, quartz, zinc and tin.
