Different tools operate at dissimilar CFM like we have a framing nailer and a wrench. Therefore, the compressor CFM rating and the tools and should match so that the devices operate efficiently. CFM or cubic feet per minute means the flowrate of air volume in an air compressor. This article explains how to increase the CFM in your air compressor.
What Determines the CFM of an Air Compressor?
Air compressors apply in different operations from households, constructions to industrial tools. All these tools require different CFM ratings, and you must understand CFM to help buy the right compressor. You can choose the right compressor suitable for the devices.
First, the power of tools determines the CFM in an air compressor. For instance, extensive tools require high CFM, while smaller devices work fine with low CFM rating like the nail gun. High CFM means more air required, while low CFM uses less air for tool operation.
Each tool has the recommended CFM. When using a single high-powered tool, the highest CFM air tool rating while dictate which air compressor to choose. If using multiple devices, you need to add up all the tools CFM and check which air compressor to operate.
Another feature affecting CFM is the presence of air receiver tanks in the compressor. The air receiver doubles the efficiency of the low CFM compressor. It’s an advantage if you are unwilling to invest in a compressor with high CFM, which is very costly.
How to Improve CFM on Your Air Compressor?
Sometimes you may need a little higher CFM than the air compressor you already have. For example, your compressor may have a flow rate of 5.7 CFM at 70 psi, and you want to operate a sprayer requiring 7CFM. What should you do? Here are some solutions to your problem.
Decrease the Pressure
First, it’s good to understand the relationship between pressure and CFM. Power= volume/ time where volume/ time is pressure. That means you need to lower the pressure down to increase power, which is the CFM. Each tool has a minimum limit of pressure to work. Therefore, by setting the dial lower to the minimum point, maximizing the CFM is possible.
Setting the regulator down slows the airflow in the tank and allows the compressor to keep filling the tank for a longer time. Thus, the CFM of the compressor increases, multiplying its efficiency. The higher the air compressor’s pressure, the higher the air tool demand flow rate, which becomes harder for the compressor. But when you lower the pressure, the compressor can keep up with this amount of CFM needed.
Advantages
- It brings a greater lifespan to your compressor and proper maintenance.
- It allows more time for the compressor to keep filling.
Drawbacks
- The method only allows you to achieve a certain level; the tool’s pressure continues to drop until there is insufficient air to properly run the device.
Hooking two Air Compressors Together
If the method is still not enough, connect another air compressor. You need three hoses, two of which connect the compressors and the third one for connecting the two hoses. The third should have three holes, two for inputs and third for output. Complete the process by attaching the output hose with your tool.
After completion, you will achieve the highest CFM. The more top airflow that you reach will be the total amount of the two compressors.
Advantages
- The method is efficient at first and gives high CFM.
Drawbacks
- Compressors require more time to adapt to the air in the two tanks.
- Leads to overheating and breakdown of the compressors
- It causes lousy maintenance.
Buying a More Powerful Compressor
Purchasing a compressor with a higher CFM is the best and effective solution to your operations. Consider the tool you anticipate using with the highest CFM and buy a compressor meant for that output need for the best results.
Advantages
- Efficient operation
- Proper maintenance
- Ensures long lifespan
Drawbacks
- Purchasing a compressor with the highest CFM is costly.
What Size of Compressor Do I Need to Run Air tools?
Air compressors come in different sizes, but size doesn’t determine whether it will be stronger. Instead, you assess the air requirements of your tools and determine which compressor meets the requirements.
You look at how much air it delivers, and that is the CFM rating. As a guideline air compressor for tools like inflation purposes has low CFM while for industrial purposes have high CFM. Therefore, it means larger and powerful tools require more CFM that’s more air flowrate delivered to them.
Most tools require between 70 and 90 psi, so light to a medium-duty air compressor. For instance, a framing nailer requires 2.2 CFM. So, the highest CFM you require in your compressor is 2.2 X 1.5 = 3.3 CFM in the compressor. Impact wrench requires 5 CFM, so the compressor should have 5 x 1.5 = 7.5 CFM.
You may also consider the size of the tank, which determines the amount of compressed air inside. A portable compressor, which can work for garage tools, contains a 2-20-gallon tank, but still, you can choose a smaller if working in your garage. An example is 2-4 gallons of tank size, sufficient for indoor, semi-professional nailing works with your pneumatic framing nail.
Air Tool CFM Requirements
The table shows some familiar air tools and their average CFM requirements.
| Air Tool | Avg. CFM @ 90 PSI | Avg. Operating PSI |
|---|---|---|
| Air Hammer | 4 | 90-100 |
| Angle Grinder | 5-8 | 90-100 |
| Blow Gun | 2-3 | 90-100 |
| Brad Nailer | 0.5 | 70-90 |
| Die Grinder | 5 | 70-90 |
| Disc Sander | 20 | 90-100 |
| Drill | 4 | 70-90 |
| Framing Nailer | 2 | 100-130 |
| Grease Gun | 3 | 120-150 |
| Hydraulic Riveter | 4 | 90-100 |
| Impact Driver (1/2") | 4 | 90-100 |
| Impact Driver (3/4") | 7 | 90-100 |
| Impact Driver (1") | 12 | 90-100 |
| Impact Wrench (3/8") | 3 | 90-100 |
| Impact Wrench (1/2") | 4 | 90-100 |
| Impact Wrench (1") | 10 | 90-100 |
| Orbital Sander | 6-9 | 70-100 |
| Paint Spray Gun | 4-8 | 90-100 |
| Ratchet (1/4") | 3 | 90-100 |
| Ratchet (3/8") | 4 | 90-100 |
| Speed Saw | 4 | 90-100 |
| Staple Gun | 2 | 70-90 |
| Tire Inflator | 2 | 125-150 |
How to Get the Best Out of Your Air Compressor
To ensure your air compressor gives you the best practice the following;
Carry Out Proper Maintenance
Inspect and clean water jackets to help regulate temperature and avoid overheating.
Minimize Unwanted Moisture
Moisture leads to loss of pressure between compressors and point of use. Do routine inspections to ensure dry air and delivery at the intended force.
Ensure Proper Lubrication
Use lubricant with specific base oils and additives formulation to protect your air compressor against rust and corrosion.
Prioritize Your Air Filter
The filter ensures cold and clean air passes through the system. Use the correct filter and maintain it properly for more extended filter change intervals and reduced loading time.
Use One Tool at A Time
You will enhance your air compressor efficiency and prevent it against overheating and breaking down.
What is the Best CFM rating for a Home Garage Air Compressor?
You may not require a much stronger compressor for a home garage due to the kind of applications you carry out. The best CFM rating is anything between 9 CFM and 14 CFM. 9 CFM is suitable for tools needing less power, and 14 CFM for more potent tools.
What is the Difference Between PSI and CFM?
CFM is a unit that shows how much air is flowing out per minute, which measure the volume, Cubic Feet Per Minute. While PSI, pounds per square inch, indicates the pressure level of air in a compressor.
Conclusion
To increase CFM in an air compressor, you can consider three methods, as mentioned above: decreasing the pressure, connecting two air compressors, or buying a powerful one. If you want to maintain your machine safely, you might reduce the PSI to increase CFM.
However, if you have to increase the CFM, you need to be competent, ensuring that no issue occurs. But for best results, ensure you choose an air compressor that matches your tools’ power needs so that you don’t reach a situation that you require to increase the CFM.