Why Does The Ultrasonic Vibrating Screen Sometimes Fail To Screen?

The technical and economic indicators of the screening process are screening efficiency and productivity. The former is a quality indicator and the latter is a quantitative indicator. There is a certain relationship between them and many other factors, which determine the screening results. The factors affecting the screening process can be divided into three categories: 

Physical properties of screened materials

Including the particle size composition, humidity, mud content and particle shape of the material itself.

When the fine particle content of the material is large, the productivity of the sieve is also large. Generally speaking, the screening efficiency will decrease when the humidity of the material is high. However, the larger the mesh size, the smaller the impact of moisture. Therefore, for wet materials with large moisture content, in order to improve the screening process, the method of enlarging the mesh size or wet screening can be adopted. If the mud content of the material is large (when the mud content is greater than 8%), wet screening or pre washing shall be adopted.

Influence of screen surface structure parameters

The linear vibrating screen makes the particles and the screen surface move vertically, so the screening efficiency is high and the production capacity is large. The relative movement of particles and screen surface is mainly parallel bar screen, plane vibrating screen and cylinder screen, which have low screening efficiency and production capacity.

For a certain material, the productivity and screening efficiency of the screen depend on the size of the screen. The productivity depends on the screen width, which is high. The screening efficiency depends on the length of the screen surface, and the long screen surface has high screening efficiency. Generally, the aspect ratio is 2.

The larger the effective screen area (i.e. the ratio of the mesh area to the entire screen surface area), the higher the unit area productivity and screening efficiency of the screen surface.

The larger the mesh size, the greater the productivity per unit screen surface and the higher the screening efficiency.

Influence of production conditions

When the load of the screen is large, the screening efficiency is low. To a large extent, the flatness of the circular vibrating screen depends on the size of the mesh and the total screening efficiency; The larger the mesh, the lower the screening efficiency, the higher the productivity.

The uniformity of feed is of great significance to the screening process.

The inclination angle of the screen shall be appropriate, which is generally determined through tests. In addition, the amplitude and vibration times of the screen are related to the structure and physical properties of the screen. In a certain range, increasing the vibration can improve the screening index.