Dust bag surface filter

The mechanism of the surface filter of the dust bag is very simple, that is, a thin layer of filter medium with a diameter smaller than the required particle size is used to capture the particles. The surface filter medium is a woven single-layer structure. Therefore, although the pore size of the filter medium is smaller than the particle size of the dust to be collected, when the air carries the dust through the filter medium, the dust particles are easy to be on the small holes of the filter medium Bridge, so that the pore size of the filter medium becomes smaller.

As the amount of dust collected by the dust bag increases, the powder cake on the surface of the filter media acts as a filter medium, and the filter medium itself only serves as a support for the powder cake. The average pore size of the powder cake is smaller than the particle size of the dust to be captured, so the dust in the mixed air stream can be captured. “Surface filtration” is named because the dust particles are collected on the outer surface of the gradually thickened powder cake. The filter medium is usually cotton cloth, but it can also be paper, perforated metal film or sand layer. When the mixed airflow passes through the filter medium, the dust in it is deposited on the surface of the filter medium to form a filter cake. At this time, the filter cake (also known as the initial adhesion layer) is really used for filtering. In surface filtration, the average velocity of the mixed air flow through the filter medium is called the apparent velocity.