Every compressor is equipped with an air intake filter on the suction side, to prevent solid pollutants contained in the ambient air from entering the compressed air system. Air intake filters are largely adapted to the intended application and there are many differences in type, design and size. The most common air intake filters are constructed according to the following basic principles: Cyclones, which hurl out the dust through centrifugal forces Wet air filters, which bind the dust by means of a liquid Dry filters, exercising a screening effect. Filter efficiency, characterised by the degree of dust removal, indicates which percentage of the dust contained in the air is actually retained, and this by reference to an AFI test dust composition.
Table 3.4.1.1| Test Dust Composition | Grain Sizes | Share |
|---|
| Street Dust | 0 - 5 µm | 28% |
| 5 -10 µm | 13% |
| 10 -20 µm | 11% |
| 20 - 40 µm | 13% |
| 40 - 80 µm | 7% |
| Rust | 0,08 µm | 25% |
| Cotton Linters | | 3% |
