What is Air Compressor Capacity?
When starting a project that requires using an air compressor, you must consider a few things beforehand. One of those things’ is your pressure (PSI) which is straight forward and is determined by the tools you use on the job.
The other factor and the one that is sometimes overlooked is the total air capacity you need to be pushed out which is measured as cubic feet per minute (CFM) and is determined by the total capacity requirements for all the tools and equipment you going to use at once.
CFM will tell you how much pressurized air you can work with where the PSI will tell you how strong that air that is being pushed out.
A small compressor and a large compressor can have the same PSI, but the larger one will have a greater capacity. Don’t confuse the size of the tank with the capacity however, a large tank can still have a small compressor.
CFM can also be expressed as SCFM (Standard CFM). This number is usually larger because it measures the air in an unpressurized and regulated or standard state.
Meaning since CFM is pressurized, usually 90 PSI, it always the smaller number. However, these measurements are of the same feature and neither one is better than the other.
Many people consider the horsepower (HP) to be an important thing to consider, however, the amount of HP won’t tell you if you have enough capacity requirements for your project.
In general, the greater your horsepower, the higher your CFM for your compressor. But you still need to figure out your capacity requirements.
The steps you must take to find out the CFM you’ll need for your project are simple;
- Find out what are the capacity requirements for each of the tools and machines you’ll be using.
- Add them all up.
This is the maximum capacity and should be in the ballpark of the CFM for your compressor.
So let say for your project, you are planning on using;
- One paint shaker needing 3 CFM
- and two sprays guns needing 9 CFM
the total CFM you be using is 21 CFM
This is important to figure this out especially if you plan on having two or more people working with tools at once. Miscalculating the CFM can grind your work to a halt and lead to unnecessary delays.
Generally, the bigger the project the more CFM is required. So next time you are looking at getting an air compressor, keep in mind what you’ll be needing it for and whether or not you’ll be using two or more tools at once. This will give you an idea oh what compressor will work for your needs.