Safety production is greater than days, and safety responsibility is more important than mountains. At present, using air mill to produce ultra-fine powder is a common way, but there are many safety problems in the use process, which have not attracted enough attention, which is not conducive to the personal health and safety of operators. Therefore, it is necessary to understand its working principle, find out potential safety hazards, and deeply carry out safety protection and management.
Airflow comminution technology has the advantages of high strength, regular particles, smooth surface, narrow particle size distribution of finished products, less pollution, high purity, and can comminute low melting point and heat sensitive materials. It is an effective method for ultra-fine comminution. In the airflow crushing, it is important to make the airflow reach a considerable speed, so that the materials can obtain enough energy, and the design of the nozzle, which is the key component to make the airflow meet the requirements, is particularly important.
The nozzle design determines the overall performance of airflow comminution. The structural design of the nozzle of the air mill is analyzed and studied. According to the characteristics of the nozzle, the design method of the three-dimensional axisymmetric nozzle is put forward.
Working principle of air mill
Through the nozzle installed around the crushing chamber and using the pressure energy of compressed air, a high-speed air flow track is formed in the crushing chamber. This jet air flow makes the powder subject to the effects of impact, shear, compression and other forces, resulting in fierce friction between the powder. When the external stress is greater than the internal stress of the particle itself, the purpose of crushing can be achieved.
In the crushing chamber, due to the action of centrifugal force, the function of powder classification can be achieved. According to the working principle and practical operation experience of air flow crusher, it is found that the main safety problem involved in the process of sample crushing is dust hazard.