It can be tough to know how many CFM you need in an air compressor to operate your air tools. Too little CFM and you won’t be able to run your tools continuously—or at all!—and too much CFM could mean you’ve overspent on your air compressor.
To help you find the compressor that’s right for you, we’ve developed this helpful air tool consumption chart. But before we get into the CFM consumption chart, let’s talk a little bit about why CFM matters to you…
Pneumatic Tool CFM Requirements
Every pneumatic tool is rated for CFM, or “Cubic Feet Per Minute”, and the same goes for air compressors. CFM represents the volume of air that is produced by your air compressor or required by your air tool.
Your tools’ CFM requirements give you an idea of what you need your air compressor to do, but it’s not enough to simply match the air tool’s rating and the compressor’s rating 1:1. In this article, we’re going to help you better understand how many CFM you need to run your air tools.
Continuous vs. Intermittent Use
Air tools need a CFM that matches the manufacturer’s guidelines, but what air tool you have and how you use them matters. For example, if you’re using an impact wrench, are you:
- continuously holding the trigger down while you work, or
- are you using it in quick bursts with short breaks in between use, allowing the air compressor to catch up?
Do you use tools for lengthy periods of time? Or are all of your tools only used for a few seconds here and there? These are the types of questions you need to ask yourself when you start to determine your CFM needs.
If your application requires you to run air tools for an extended length of time, an air compressor with a 100% duty cycle is recommended so you can operate your tools continuously.
By contrast, tools only used intermittently may be able to get away with a less powerful air compressor that uses an air receiver tank, which may save you money.
Another common scenario that impacts CFM requirements is using multiple tools at once. Running more than one tool at a time can be a highly efficient way to get things done, especially when you have two or more people working on a single job. However, if you’re running multiple tools at the same time, you’ll need to combine the CFM requirements of each of the tools that will be running to determine your total CFM requirement.
For example, let’s say your team uses the same air compressor to power a ½” drill that requires 30 CFM, and a grinder that requires 60 CFM. If you use these tools at the same, you would add 30 CFM + 60 CFM for a total demand of 90 CFM. When choosing equipment, you would likely need an air compressor that can reliably produce 90 CFM of air.
Air Receiver Tanks
Air receiver tanks are another factor you should consider when determining your CFM needs. Many air compressors require an air receiver tank—in fact, this is always the case with reciprocating air compressors. “Recips” need an air receiver tank and can only run at 100% duty cycle until the receiver tank runs out of stored air (or the compressor overheats from working too hard – but that’s another story…)
In some scenarios, air receiver tanks can help a lower CFM air compressor keep up with a higher CFM demand, and can be a good strategy when you don’t want to invest in a higher CFM air compressor. These air receiver tanks can vary in size from 5 gallons to over 100 gallons.
Air Tool Consumption Chart
Still wondering what this means for you? We’ve put together a handy air tool consumption chart to help give you an idea of how many CFM you need to run your air tools. We’ve also included 6 tips for choosing an air compressor, the average CFM at load (100% duty cycle), the suggested air compressor CFM, and our recommended rotary screw air compressor based on your CFM needs.
Here’s a sneak peek:
|30-40 CFM Air Compressor||60-70 CFM Air Compressor||150 CFM Air Compressor|
|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||60lb jackhammer||90lb jackhammer|
|Backfill tampers||Backfill tampers||Air knives|
To view the rest of the info, download our full air tool consumption chart here!
VMAC’s Rotary Screw Advantage
Depending on the product, VMAC air compressors deliver anywhere from 30 to 140 CFM at 100% duty cycle, which means you’ll never have to wait for air. VMAC air compressors also don’t require a bulky air receiver tank, thanks to the rotary screw technology, which allows them to operate at max efficiency 100% of the time. Not only are VMAC air compressors lighter and smaller, you’ll get jobs done faster, improve productivity, and be more profitable.