Vertical roller mill, referred to as a vertical mill, is a large grinding equipment widely used in the grinding and processing of cement raw meal, cement clinker, slag, and cinder. Its application areas also include electric power, metallurgy, chemical industry, non-metallic minerals, and other industries. It can integrate crushing, drying, grinding, grading, and transportation, and is used to grind block, granular, and powdery raw materials into the required powder. shape material.

 

The main components of the vertical roller mill include the body, grinding disc device, and transmission device. A centering structure for determining the center of rotation is provided between the machine body and the grinding plate device, and a rotary guide rail is fixedly provided at the bottom of the grinding plate device so that the grinding plate device can be rotatably supported on the machine body. The transmission device is connected to the grinding disc device. Since it does not bear the weight of the grinding disc and high axial loads such as grinding pressure, a general-purpose reducer can be used, which has a compact structure and reliable operation.

 

The working principle of the vertical roller mill is as follows: the raw material enters the feed port of the machine through the feeding device and is then clamped by the grinding roller and the grinding disc. The driving device drives the grinding roller to rotate at high speed. The raw materials are squeezed, sheared and rubbed between the grinding roller and the grinding disc, thereby being ground into fine particles. At the same time, hot air enters the mill from the air inlet to help the material dry. By adjusting the separator, the thickness required for different products can be achieved. The ground powder is taken away by the airflow through the separator, the fine powder enters the collection device, and the coarse particles return to the grinding disc for back-grinding.

 

Compared with other equipment, such as ball mills, vertical roller mills have the advantages of low energy consumption, low noise, and a clean environment with no dust. It adopts the principle of material layer grinding. The power consumption of the grinding system is 20% to 30% lower than that of the ball mill. As the moisture content of the raw materials increases, the power-saving effect becomes more obvious. In addition, the vertical roller mill adopts a fully enclosed system and works under negative pressure, resulting in a cleaner operating environment. The residence time of materials in the vertical mill is also short, only 2 to 3 minutes, so that the chemical composition and fineness of the product can be quickly measured and corrected.

 

However, vertical roller mills are not suitable for grinding hard and abrasive materials because their service life may be short and maintenance will be more frequent.