By . Air Compressor. At Sunday, September 16th 2018, 03:38:14 AM.
All reciprocating air compressors throw out some oil with the air they compress. When the tank reaches its designed pressure limit, a switch will interrupt electrical power to the motor. Simultaneously, a certain amount of oily air will be released into the shop environment. You may see oil collecting on the wall behind the compressor and on the pump and compressor as well over time. This is not cause for alarm but periodic cleaning may be needed.
Air output of a compressor is expressed in standard cubic feet per minute (SCFM) or just cubic feet per minute (CFM). Not all 5 HP compressors put out the same volume of air per minute. This is a function not only of motor horsepower but also the efficiency of the air compressor pump the motor is powering. The higher the CFM, the less your air compressor will have to cycle on and off to keep up with the demands you are putting on it. A small compressor pump on a huge tank will produce no more air than on a small tank. The only difference will be in the number of times the compressor cycles on an off each hour and the time it takes to recompress the tank on each cycle. In the final analysis, you need to pay attention to SCFM (or CFM) more than you do motor horsepower or tank size. Air flow is the end product of any compressor and the CFM must be sufficient to the job at hand.
I happen to be just a small portable air compressor. I live with a nice man named John who owns a small construction business. He takes me with him wherever he goes. Usually, we visit job sites where John goes up to other men and talks to them about important stuff. I just hang out in the truck waiting patiently. Sometimes, John will come back to the truck and take me out to start working. These are the good days. Other times, we have to drive off and come back another day.