Screw Air Compressors
Rotary screw compressors come in two main versions, oil flooded rotary screw compressors and oil-free screw compressors. Oil-free models deliver 100% oil-free air, but are more expensive. Oil-injected or lubricated version needs oil to operate properly. This oil is later removed by the oil separator, but some oil remains in the air supply.
Rotary-screw compressors tend to be smooth running with limited vibration, thus not requiring a specialized foundation or mounting system. Normally, rotary-screw compressors are mounted using standard rubber isolation mounts designed to absorb high-frequency vibrations.
Screw compressor air delivery technology can deliver air at higher air pressures than regenerative and positive displacement blowers (see below, 1.25 Mpa is 12.5 Bar).
Oil free silent screw compressor
These are completely oil-free as there is no oil lubricant used in the air delivery system.
Pressure conversion table
Belt drive, oil lubricated air screw compressor