How Do Air Compressors Work?

Air compressors are one of the most useful tools around.

While the average compressor can easily inflate most car or bike tires, that’s not all they’re good for. From woodworking projects to filling scuba tanks, or even industrial applications, compressors are versatile tools that can get a variety of jobs done quickly and efficiently.

But how do air compressors work?

As useful as air compressors are, the nuts and bolts of how they operate is a mystery to many. Keep reading for a closer look at how air compressors work.

How Air Compressors Work

Like the name implies, air compressors compress air into a smaller space. In principle, when air is compressed, it will occupy a smaller area, but the volume will increase with the amount of air pumped into the smaller area.

It’s the pressure created by the air being squished down into a smaller space that makes air compressors so useful.

To move air from the wide open outdoors down into a tank, most compressors use a piston to pump air into the tank. An inlet valve allows air to enter the tank, then as the cylinder compresses the air, it pushes it into the tank in compressed form.

If you’re familiar with internal combustion engines, you’re probably thinking that compressors sound pretty similar. And you’d be right.

Most compressors use a single or two piston design that’s very similar to an internal combustion engine. But, rather than compressing fuel and generating power from the combustion within the engine, a compressor simply uses the piston (or pistons) to pump air into a tank.

How Power Is Calculated

Most compressors will come with a horsepower rating clearly displayed on the unit. But, this isn’t the only indicator of power and perhaps not the best measurement for most users.

A better measurement of air compressor power is how much air pressure can actually be delivered. For compressors, this measurement is typically indicated in cubic feet per minute (CFM) or the more universal standard feet per minute (SCFM).

Both CFM and SCFM are typically calculated at a specific pressure. So, a compressor may put out 2.5 SCFM at 90 PSI, but more or less power at different pressures.

Types of Air Compressors

Compressors come in many shapes and sizes, but most rely on the positive-displacement, piston system for air compression.

Single and twin piston models are available, with single pistons being most common in smaller, single stage units. Larger, twin piston models are available and are typically used in commercial or industrial applications.

Putting It All Together

Air compressors are actually very simple tools.

Don’t let the noise or the pressure confuse you.

Whether you’re filling a scuba tank or remodeling your kitchen, the next time you’re working with a compressor, think about how it works–and how simple it’s making your work.

Just remember that compressors can be dangerous if used improperly or poorly maintained.

Now that you know how compressors work, take a look at the rest of the Max-Air blog for more on how these handy tools are used.

Looking for the right air compression solution for your needs? Give us a call at 830-257-5006 or email