The oil-free screw compressor element
No oil implies that there is no essential oil for sealing the rotors and for cooling the compressed atmosphere, elements and rotors. … The element is definitely cooled by cooling drinking water that flows through special pockets in the element casing.
In a lubricated screw compressor, the lubricant comes in direct in touch with the compressor inlet air and compressed air. … The oil Oil-free Screw Air Compressor china contains anti-oxidants to try to reduce 
the break down of the lubrication properties due to internal conditions.