Rotary screw air compressors are used to supply large volumes of compressed air for air tools and other industrial applications. Because they are generally used commercially, there is a high need for reliability. As every industrial engineer knows, the key to reliability is reliability centered maintenance. However, a balance must be struck in establishing a maintenance schedule. A maintenance schedule that is too aggressive can be wasteful because air compressor parts and fluids may be replaced when they are still usable. As a result, maintenance costs are greater than they need to be. On the other hand, a maintenance schedule that is too lax risks damaging equipment. This leads to…