Fine filters (precision filtration)

Description

Fine filters for compressed air, fitted at the compressor outlet to remove moisture, particles and oil aerosols: this is what is called filtration.

Why filter?

Even after the air/oil separator, the air receiver and the dryer, compressed air still contains water, very fine oil particles and dust. Fine filters protect air tools, machines and the quality of finishes, especially in painting.

How to install them?

Fine filters are fitted in series at the compressor outlet, from the coarsest to the finest. Each filter is drained and its cartridge is replaced when the pressure drop increases: a differential pressure gauge helps you know when.

The filter must be sized for the compressor's air flow. Air flow, filtration grade and fittings to be specified in your quote request.

Three filters at 8 bar, five at 16 bar

A basic set of precision filters has three filters of different grades, each with its own role:

1. the first one performs an initial filtration, in particular of the moisture in the compressed air;
2. the second one refines the filtration and acts as an additional protection;
3. the third one removes the very fine oil particles and oil aerosols still present.

This set suits 8 bar installations. For a 16 bar high-pressure compressor, five precision filters are generally used, and they must be high-end models designed for high pressure. State the pressure of your network in your request.

Which filtration for which use?

For standard air tools, a particulate filter is often enough. For blowing parts or painting, a coalescing filter is added to trap oil aerosols, followed by an activated carbon filter for vapours and odours. The ISO 8573-1 standard describes these air quality classes: our guide explains it simply.