The difference between 1-stage and 2-stage piston compressors

The main difference between a 1-stage and a 2-stage piston compressor is how often the air is compressed between inlet valve and tool nozzle. As the name indicates, in a 1-stage (or single-stage) compressor, it is compressed once and in a two-stage compressor twice.

In the former, the air is routed to a storage tank after being compressed in a single stroke. In the latter, however, the air is moved to a smaller piston via a cooling tube that reduces the air temperature. There it is compressed for a second time, which results in an increase in pressure.

Because the pressure of the compressed air generated by a 1-stage piston compressor is lower (a maximum of 10 bar), these less expensive models are usually the right choice for smaller jobs that do not require a continuous air supply. That not only includes compressors used at home but also those in many small businesses. Typical applications include nail guns, sanders and drills.

Conversely, 2-stage piston compressors are used for jobs requiring high-powered tools and a continuous supply of compressed air. They can generate an air pressure of up to 30 bar, which is sufficient to power lifts, paint sprayers, ratchets and other heavy-duty pneumatic tools typically found in production facilities.

As mentioned above, a common mistake people make is that they confuse the number of cylinders with the number of compressor stages. The designations of 1-stage and 2-stage piston compressors has nothing to do with the number of pistons. A single-stage compressor, for example, can have one, two or even three pistons. These terms merely describe which process is used to compress the air.

However, if you still have questions about this or any other issue related to 1-stage and 2-stage piston compressors, then an Atlas Copco specialist stands ready to support you.

Ask an air system professional about the best options for your needs.