The overall mechanism of an air compressor is a piston or rotary element (e.g. rotary screw or vane) that allures atmosphere, which is compressed right into a storage tank. Naturally, because the piston or rotary component needs to move regularly and smoothly because of this to work, it generally needs to be lubricated.
In a lubricated air compressor, there is lubricating oil which keeps the piston or rotary element running smoothly without damaging the system. The lubricant also helps to dissipate heat and keep maintaining air compression efficiency.
Oil-free air compressors also use a piston or rotary element, but they get around the lubrication problem by coating the compression element with a pre-lubricating material like Water Lubricated Air Compressor Teflon. Some oil-free compressors may also use water instead of oil for the lubricating and cooling procedure. These alternate materials shield the pump and allow the mechanism to move smoothly with no need for any oil-based or synthetic lubrication.