Are you wondering, what is cfm for air compressor? But before that let us take a peek on what is an air compressor.
An air compressor is an electric device. It converts power into potential energy. This compressor uses an electric motor, diesel engine, etc. The air compressor works for any gas or air. The air compressor with lower cfm ratings used for passenger tire inflation. Again the air compressor with higher cfm ratings used for industrial applications.
The air compressors are one of the most efficient and cost-friendly devices. The air compressors help in construction, repairing automobiles or in DIY craft projects. The compressors can be found in different sizes and types. But common types are:
- Portable air compressors.
- Stationary air compressors.
Portable air compressors:
In simple words, these air compressors are portable. They can be used anywhere. They are flexible to use. They are used for inflating sports equipment or for inflating air mattresses.
Stationary air compressor:
These air compressors can’t be moved from one place to another. They are, in simple word, static. They come in large sizes. These air compressors also provide more power than portable air compressors. These air compressors contain larger tanks. As a result, they can maintain cfm as desired.
How air compressors are measured?
The air compressors are measured in two ways.
- Pounds per square inch or PSI
- Cubic feet per minute or in short CFM
The effectiveness of the air compressor is determined by these measurements. While buying an air compressor, you must identify psi and cfm needed for the air tool. Try to use tools with the highest psi and cfm requirements. If you use several tools, you must total the cfm needed for each tools.
Buy an air compressor with 1.25 or 1.50 times more cfm airflow than the air tool needs, to get the best results. This will make the compressor work with more efficiency.
What is cfm for air compressor?
The elongated form of cfm is cubic feet per minute. Measurement of the flow of pushed out air by a compressor is cfm. In a simple sentence, we can say, cfm is the measure of air flow velocity pushed out of an air compressor.
It is very difficult to know how many cfm an air compressor needs to operate it’s air tools. As low cfm won’t run tools properly, again high cfm means overspent of money. Air tool’s cfm requirements give an idea about what an air compressor does. Cfm for air tools must match the manufacturer’s guidelines. Cfm is also known as SCFM or ACFM. SCFM stands for standard cubic feet per minute and ACFM stands for average cubic feet per minute.
What is the difference between psi and cfm
|PSI stands for pounds per square inch.||CFM stands for cubic feet per minute.|
|It is the measurement of the discharged pressure of the air compressor.||2. CFM is the measure of the volumetric flow of the air compressor.|
How is air compressor cfm calculated
Some manufacturers may represent false cfm of an air compressor. For this, it is better to determine real cfm by yourself. If you know how much cfm your air tools need, you can know how powerful compressor you need.
Do you want to calculate the cfm of your air compressor? No worries! Follow the below steps.
Check the volume in gallons of the air compressor tank. It is marked by the manufacturer on the tank.
Divide the volume found in the tank by 7.48. As one cubic foot equals 7.48 gallons. So, we get the volume of the tank in cubic feet.
Release the air from your air compressor.
Start refiling the air compressor with the air. Record the time it takes to refill the tank of the compressor.
Record the pound per square inch or in short psig at two separate times. At first, at the time the compressor kicked in and at the time compressor kicks out.
Now, subtract the recorded psig found in step4. That means psig at the time compressor kicked in from the psig at the time compressor kicked out.
Divide the result of subtraction by 14.7. The result is the amount of pressure in atm added during the filling cycle of the tanks.
Multiply the volume of the tank found in step2 with the amount of pressure found in step6. This result is the number of cubic feet the compressor pumps in the time it took to refill it’s tank. (time recorded in step4)
Divide the result of multiplication found in step7 by the number of seconds it took to pump this result. Multiply the found answer by 60. The result is the cfm of the air compressor.
What is the cfm required for most common tools?
If you don’t want to do the above complicated math. Then, Let us take a look at cfm needed for most common tools:
30 to 40 cfm needed for air compressors like:
- 3 by 4 inches impact wrench
- Chipping hammers
- 2 inches horizontal grinders
- Tire inflation
- Die grinders
- Backfill tampers
60 to 70 cfm needed for air compressors like:
- 1 inch impact wrench
- Large vertical and horizontal grinders
- OTR tire inflation
- 60lb jackhammer
- Backfill tampers
150 cfm needed for air compressors like:
- Trenchless piercing tools
- Pneumatic saws
- Post pounders
- Rock drills
- 90lb jackhammer
- Air knives
CFM requirements based on tools:
To answer the question, What is cfm for air compressor? We can simply say it is one of the most essential parts of the air compressors. The air compressor’s cfm output has to be more than needed by it to work efficiently. CFM increases as PSI decreases. A higher CFM rating can deliver more air. If you want to use several tools, total the cfm needed for each tools.