Three Stage Filtration
Stage 1: Gravitational Setting
Compressed air leaves a desiccant dryer containing dust concentrations typically in the range of up to 0.05 ppm by weight in heatless type dryers and up to 5 ppm by weight in heated type dryers. Particle size ranges from 200 microns to about 1 micron. This desiccant laden compressed air enters the filter housing where a reduction in air velocity and a sharp change of direction cause particles in the range of 200 to 20 microns to drop to the bottom of the housing.
Stage 2: Surface Filtration
The air stream then enters the outside of the filter cartridge and flows through layers of glass fabric cloth. Small diameter fibers, which form a web in the openings between thread strands, cause a dust layer to form as dust bridges the pores. Dust continues to collect on the outside of the cloth as separate loose particles. The voids between these particles form pores and flow-passages and become an efficient filter in itself.
As the dust bed continues to thicken it reaches a point where outer layers of dust shed off the cartridge into the bottom of the housing.
Stage 3: In-Depth Filtration
Air next travels through a multi-layer graded in-depth filter media where all remaining fines one micron and larger are captured.
A final wrap of glass fabric cloth prevents fiber migration.
