When considering the purchase of a new air compressor, always do the following;

Determine the REQUIRED pressure

Many people will look for the highest pressure compressor available. (We have found some of our competitors’ technicians, acting as sales people that have a minimal grasp of compressed air theory, telling end users that higher pressure will assure more air. This is simply untrue. Pressure and flow have an inverse relationship. I’ll cover that in a different post.) Most air tools require only 90 psig. Higher pressure simply leaks by the vanes in the air motor. In addition higher line pressure will cause more leaks. Higher pressure also uses higher amperage. Again, I’ll cover the relationship of amperage to electrical costs in a future blog entry.

Determine required flow.

Most machine tool or machining center manufacturers will supply the required pressure but apparently haven’t a clue about flow. If you find yourself in this situation, give us a call. We have solved this dilemma many times in the past.

When flow and pressure have been determined the correct K.W. unit is selected.

At this time, power requirements will become established. The availability can be determined. If there is insufficient electrical service available, the cost for additional infrastructure can be ascertained. Who will stand the cost? The building owner? The tenant? The power company?

Quality of air must be established. Is there an ISO specification?

Is there a Military Specification that must be satisfied? Is there a specific requirement by the end user? This will dictate the compressor type, dryer type, filtration as well as any specialized receiver or piping required. The dryer type may have an impact on compressor sizing as well (i.e. a non-heated dual tower desiccant dryer or a membrane type dryer will demand sweep or purge air in the amount of 15 to 25% of the design flow of the dryer, regardless of the amount of flow through the dryer).