The oil-free air compressor has the advantages of simple and compact structure, low speed, low vibration noise, low exhaust temperature, high thermal efficiency, stable and reliable performance, and low specific power, making it the development trend of new oil-free engines.
Its working principle is to inject lubricating water into the compressor chamber and bearing continuously during the compression process through the pressure difference generated by the compressor itself. This design has the following characteristics: lubricating water can absorb a large amount of compression heat, improve the compression efficiency, and avoid the possibility of friction or seizure between rotors, star wheels, and casings due to different coefficient of thermal expansion. Lubricating water can also reduce the noise generated by high-frequency compression. The injected lubricating water can form a rigid water film between the rotor, star wheel, and casing, and the star wheel is directly driven by the main rotor. Lubricating water directly cools the self-lubricating bearings at both ends of the star wheel. The injected lubricating water can achieve airtightness, which is superior to ordinary dry screw compressors.