It goes without saying that careful selection of air line oil is also necessary to protect the equipment and ensure long life. Since the expansion of air produces a chilling effect that causes condensation, a light body lubricant is required for air line lubricators. This allows for proper feed and good dispersion in the components being lubricated.
The oil should be made to resist displacement by water and prevent rusting of internal surfaces. (Air pilot control circuits and bag type clutches do not require air line lubrication).
Note that pipe scale, condensate, emulsified and deteriorated compressor oil are all present in compressed air systems. These contaminants are removed by the filter supplied with the equipment if it is regularly drained, the filter element cleaned, and the precautions taken with the compressed air supply.
Other points: The piping for compressed air should be large enough to avoid excessive pressure drop under maximum flow conditions and have as few bends and restrictions as possible. To remove the water present in every compressed air system, pitch compressed air piping in the direction of air flow so that both air flow and gravity carry the water to traps located in the piping system. Drain regularly.