They are powered by two counter-rotating screws that compress air as it moves through the compressor. These units are designed for continuous use, capable of operating 24 hours a day, 7 days a week.
[pdf] Let me explain how a rotary screw element is built up. See this example picture of an oil-free screw element. Compressor element (oil-free type). Photo: Atlas Copco Of course, we see the two rotors (male rot.
[pdf] Check for correct oil level at the ll plug location on the compressor. The oil level is full when oil is at the bottom of the threads in the ll plug hole. Check for oil purging from the air dryer. Refer to the image below as an example.
[pdf] 
