The rotary screw air compressor has become the most popular source of compressed air for industrial applications. A major reason is its simple compression concept. Air enters a sealed chamber where it is trapped between two contra-rotating rotors. As the rotors intermesh, they reduce the volume of trapped air and deliver it compressed to the proper pressure level. This simple compression concept, with continuous contact cooling, allows the rotary screw air compressor to operate with temperatures approximately one half that generated by a reciprocating compressor. This lower temperature enables the rotary screw air compressor to operate in a "fully loaded" continuous duty cycle 24 hours per day, 365 days per year, if necessary. Its ability to operate for extended periods of time makes the rotary compressor ideal for demanding industrial applications.