The relation of physical characteristics of the paper and the filter performance

1. Ration

For filters, the ration is reflected in the weight and price. For filters, which has a certain filter area, during a certain filter area, the bigger the ration, the heavier the paper, and then filter is heavier. As the cost of the paper occupies much,  so the filter cost is relatively high.

2. Thickness

Corrugated tubular filter, the thickness of the paper can limit the maximum filter area of the filters

3. Deflection and bursting strength are used to reflect filter’s ability of resisting deformation and differential pressure. High deflection and high bursting strength can show the good durability, but if too high, it will become crisp and the filters will be easily broken

4. The quantity of resin that contained

The aim of adding the resin to the filter paper is to increase deflection of the paper and it will be good for the fix in the process of the paper. It is usually between 10% and 30%. If resin too much, it is likely to block the filter paper’s gap structure

The relationship of the filtration characteristics of the paper and filter performance

1. The air permeability of the paper

The air permeability is the concentrated reflection of the filter paper performance and it is the chief index in the filter design. It also has close relation with the filter flow resistance property, filtration efficiency, original resistance, lifetime and performance index. The higher the air permeability, the lower the flow resistance and the original resistance, or it is the opposite. The air permeability has the opposite relation with the flow resistance.

The air permeability is also the index of the moistureproof ability of the filter. The higher the air permeability, the easier it will absorb moisture, after moisture, the filter paper will become longer. When the process size is not stable, it will influence the mass production. The process technology is bad, it even worsen the quality in serious situation. If moisture before sticking the cap, the filter length is 2-4mm and it will influence the controlling of the height of the element. If moisture after sticking, the filter paper will longer and the filter texture will be distorted and it will influence the element quality seriously.

2. The maximum aperture and the average aperture 

The maximum aperture and the average aperture can be tested through the bubbling. The maximum aperture is calculated by the first bubbling pressure. The average aperture is calculated by the group bubbling pressure.

It is usually use the bubbling point to judge the filter’s integrity, and judge the precision of according to the average aperture and the maximum aperture. The average aperture has close relation with the filtration efficiency. The lower the average aperture, the higher the filtration efficiency.