How To Improve The Screening Efficiency Of A Vibrating Screen?

Screening efficiency is an important quality indicator in the screening process. Screening efficiency refers to the degree to which fine particles are separated from the mixture during the screening process and the quality of the screened product. Improving the screening efficiency of vibrating screens has always been one of the important issues in the crushing workshop of mineral processing plants.

The purpose of separating is to ensure that all particles smaller than the screen openings pass through the undersize product. However, achieving this goal is very difficult. The product on the screen always contains some fine particles smaller than the screen openings. The degree of complete screening refers to the ratio of the mass of the screened product to the mass of material smaller than the sieve aperture contained in the feed.

How to improve the screening efficiency of a vibrating screen?

1. Adopting large size screen

Large circular vibrating screens increase vibration force and amplitude, thus increasing the impact and shear stresses on the material from the screen plate. This overcomes the adhesion between mineral particles and reduces screen clogging. It allows the material to be screened to quickly loosen, stratify, and pass through the screen, improving screening efficiency.

2. Increase screening area

Reducing the amount of material per unit screen surface can improve screening efficiency. The screening efficiency is highest when the actual material volume on the screen surface is approximately 80% of the screen’s capacity. When using a screen as a grading device, due to the large number of fine particles, sufficient screening area and an appropriately longer screen surface are necessary. A length-to-width ratio of 2:1 or higher is beneficial for improving screening efficiency.

3. Use a reasonable tilt angle

Controlling the flow velocity of materials on the screen surface is crucial. A larger inclination angle results in faster material movement and higher production capacity, but lower efficiency. To achieve higher screening efficiency, the material velocity on the screen surface is generally controlled below 0.6 m/s. Therefore, the screen surface should maintain an inclination angle of approximately 15°.