Air compressors come in many sizes, but the size doesn’t determine whether an air compressor is powerful enough for your air tools. Instead, you should assess your tools’ air requirements and find an air compressor size that can meet those requirements.
Why Bigger Isn’t Always Better
We’ve all heard that bigger isn’t always better, and that’s exceptionally true when it comes to air compressors. There are large air compressors with low air output, and there are compact air compressors with high air output.
Some manufacturers, like VMAC, have put significant research and development time into creating air compressors that are as small and lightweight as possible without compromising on power. But not all manufacturers are focused on minimizing size. Therefore, it’s impossible to assess an air compressor’s capability by its size.
How To Determine Your Air Compressor Size
Instead of assessing an air compressor’s capability by its physical size, operators should look at how much air it delivers, measured in Cubic Feet Per Minute (CFM). As a guideline, most air compressors meant for powering tools fall in the 10 to 110 CFM range.
Air compressors with lower CFM ratings are meant for passenger tire inflation and small tools, such as chippers, grinders, and sanders, while higher CFM air compressors are designed for industrial applications and larger tools, including 1” impact wrenches, 90 lb jackhammers and rock drills.
To narrow down your specific requirements:
- Look at the CFM requirements for the most powerful air tool you use.
- Note whether the CFM rating is for 100% duty cycle, as many continuous-use tools are still rated as if you’re only using them 50 to 60%—you will need a higher CFM rating if you don’t want to stop regularly.
- If you use more than one tool simultaneously, combine their CFM rating to determine your need.
Once you know how much CFM your air tools require, you’ll also learn how powerful your air compressor needs to be. Try to find an air compressor sized to meet your air output needs without going too far over.
Air Receiver Tanks
Air receiver tanks are a great way to increase the amount of air available over the short term. These tanks are required for reciprocating air compressors, while rotary screw compressors generally don’t require a receiver tank due to their 100% duty cycle capability.
However, in some cases, operators can choose a lower CFM rotary screw air compressor if they have an air receiver tank. For example, if you need 45 CFM of compressor air and you’re deciding between a 40 CFM air compressor and a 60 CFM air compressor, the 40 CFM air compressor with an additional air receiver tank may be the most cost-effective option.
You can learn more about air receiver tanks, including sizing information, in this article.
Air Tool Consumption Chart
The best way to get an accurate measure of your air power needs is to look up the requirement of your specific tools. However, if you don’t want to look up your tools’ CFM ratings, the fastest way to determine how much air you need is to look at an existing Air Tool Consumption Guide. These guides break down the typical CFM required for most tools and make it easy for operators to know their CFM requirements.
|30-40 CFM Air Compressor|
@100% Duty Cycle
|60-70 CFM Air Compressor|
@100% Duty Cycle
|100-140 CFM Air Compressor
@100% Duty Cycle
|¾” impact wrench||1” impact wrench||Trenchless piercing tools|
|Chipping hammers||Sanders||Pneumatic saws|
|2” horizontal grinders||Large (3”+) vertical & horizontal grinders||Post-pounders|
|Tire inflation||OTR tire inflation||Rock drills|
|Die grinders||60 lb jackhammer||90 lb jackhammer|
|Backfill tampers||Backfill tampers||Air knives|
To view the rest of the info, download our air tool consumption chart here!
Finding The Right Air Compressor
Once you know your CFM requirements, it’s time to start narrowing down air compressors. There is a lot to consider:
- Rotary screw vs. Reciprocating
- Portable vs. Stationary
- Tow-behind, Handheld, Wheeled
- Utility mounted, Vehicle integrated
- Fuel/Power Sources
- Gas, Diesel, Hydraulic, Electric
- Multi-power Systems
Fortunately, a bit of research will help you make quick decisions about the right type of air compressor for you. Learn more about air compressors with the resources below: