Inadequate material screening will not only reduce the quality of finished materials, but also cause great waste and affect production efficiency. How to improve the screening effect of the vibrating screen? When using a vibrating screen for screening operations, reasonable measures can be taken based on the actual situation, combined with the characteristics of the material and the characteristics of the vibrating screen to improve the screening effect of the vibrating screen while ensuring processing capacity.
Factors affecting the screening efficiency of the vibrating screen: material factors and equipment factors. Among them, material factors include material moisture content, bulk density, particle size, and particle shape that affect the screening effect.
1. Material moisture content: During dry screening, materials with high moisture content or good wettability and adhesion are more likely to condense and agglomerate, causing screen holes to be blocked and greatly reducing screening efficiency.
2. Material bulk density: When the bulk density of the material is large, the screening capacity of the vibrating screen is proportional to the bulk density.
3. Material particle size: The more easy-to-sieve particles in the material, the easier the material is to sieve. On the contrary, the more difficult the material is to sieve. Particles with a particle size of d=1 - 1.5a (a is the size of the sieve) are likely to be stuck in the sieve holes of the vibrating sieve, called obstruction particles, which will affect the material's passage through the sieve holes. Therefore, the more difficult and obstructing particles the material contains, the lower the screening efficiency of the vibrating screen.
4. Material particle shape: When the particle shape of the material is spherical, it is easy to pass through the square hole and round hole vibrating screen, while when the particle shape of the material is strip, sheet and polygonal, it is difficult to pass through the square hole and round hole sieve, but it is easier to pass through the sieve with rectangular holes.
In addition to material factors, equipment factors will affect boring screening results. The screen surface, screen holes, tilt angles and other details of a good manufacturer's vibrating screen will be more accurate, and will also be tailored according to the customer's different cutting types. It can greatly reduce loss and improve screening effect and discharge quality. Equipment factors are specifically divided into screen surface size, screen surface inclination angle, opening ratio, and screen hole shape
1. Screen surface size. If the aspect ratio of the screen surface is too large or too small, the screening efficiency will be reduced. The aspect ratio of the vibrating screen surface should be within an appropriate range, generally 2.5 to 3.
2. Sieve surface inclination. If the inclination angle of the screen surface is too small, the production capacity will be reduced; if the inclination angle is too large, the screening efficiency will be reduced. Therefore, it is crucial to set the appropriate inclination angle of the vibrating screen. The inclination angle of the vibrating screen is generally 0° to 25°, while the inclination angle of the fixed screen is generally 40° to 45°.
3. Opening rate. The ratio of the aperture area to the surface area of the vibrating screen plate is called the aperture ratio. The sieve plate with a large aperture ratio has high screening efficiency and large production capacity, but has low strength and short life compared to the sieve plate.
4. Shape of the sieve hole. The shape of the sieve holes is different, and the passing capacity of the material varies greatly. Therefore, when selecting a vibrating screen, it should be noted that the aperture type of the sieve plate should be compatible with the particle shape of the material in the production line.
How to improve the screening effect of the vibrating screen? The answer is: the feeding amount should be controlled reasonably to avoid too much or too little. When feeding, the material should be fed continuously and evenly so that the material is evenly distributed along the screen surface, which can effectively ensure high production capacity and screening efficiency. In some cases, the feeding of the vibrating screen is not fed along the full width of the screen, which will cause the screen surface to not be fully utilized. Therefore, the feeding method must be carefully checked and adjusted in a timely manner during work. When the screening efficiency is not ideal, consider adjusting the inclination angle of the vibrating screen machine. An appropriate inclination angle will help reduce the thickness of the material. Increase the opening rate of the vibrating screen plate. A high opening rate is conducive to improving the screening effect. Generally, the opening rate of stainless steel welded screen plates is high. To reduce the hole blocking rate on the screen surface of the vibrating screen, consider selecting a screen plate with a self-cleaning function. Compared with dry screening, the screening effect of wet screening is better. For dry screening, the moisture content of the feed must be strictly controlled.
Material screening is an important link in the production of mines, chemical plants, cement plants and other industries. When using a vibrating screen, the above analysis is carried out and the equipment is adjusted, and the results of the screened materials will be better!
