Air compressors have endless uses. You’ll find yourself needing compressed air if you’re painting your porch, filling your football, working on your car or truck, all the way up to the most heavy-duty construction projects. We’ll provide a brief overview of the most common air compressor types, so you can get a better idea which is best for you.
Reciprocating compressors are most efficient and economical at pressures of 30 psi and under. They are generally noisier and lower capacity than rotary compressors. Reciprocating compressors are best for intermittent use. A small reciprocating compressor can be just the right fit for the occasional handyman or hobbyist.
In a piston compressor, a crank-shaft drives the pistons, which move inside a cylinder to compress the air. In a single stage compressor, the action of the piston compresses the air and delivers it to a storage tank in a single stroke. Two-stage compression further compresses the air for higher pressures, up to 175 psi.
Diaphragm compressors use a variation of piston compression where the intake element is replaced with a flexible membrane. Because the membrane and the housing are all that come in contact with the gas, these compressors can be used to safely pump toxic and even explosive gases. They can be quieter than other reciprocating compressors.
Rotary compressors generally provide the most balanced compression for applications which require pressures above 30 psi. They operate continuously, providing up to 100 percent duty cycle. They are high speed and low vibration. Rotary compressors are often preferred in industrial and construction applications.
Rotary screw compressors
Rotary screw compressors operate by the continuous rotation of two intermeshing helical screws. They are great for construction, often powering jackhammers, because they deliver large volumes of pressurized air continuously.
Rotary sliding vane compressors
The sliding vane design allows it operate without bearings, which make these compressors suitable for dirty conditions. They are designed for a long life with a wide variety of applications. You can find them in fountain drink dispensers, power steering systems and vacuum pumps. Multi stage versions can provide pressures up to 200 psi.
Rotary scroll compressors
These pumps can provide very balanced, low vibration operations. A single pump can operate at 10 horsepower, and multiple pumps can be used to bump that up to 50. The oil free version of this compressor outputs clean air which can be used in medical and laboratory spaces without risk of contamination.
You’ll want to select the appropriate compressor for your use. An auto body shop or a construction company will have different needs than you might, if you’re only occasionally operating a pump or a sander in your home. All of the compressors we’ve discussed are available in oil free or oil lubricated versions. Oil lubrication is best for reducing heat, increasing efficiency and protecting the mechanism.