Know-a-Compressor » Free tool to calculate the air flow or cfm required to operate a pneumatic cylinder


Free Tool to calculate the air flow or CFM (cubic feet per minute) of air required to operate a pneumatic cylinder

By Rajkaran Chawla : Published on 3rd November 2017 : Updated on 4th November 2017

Pneumatic cylinder or air cylinders are devices that use compressed air to produce a force in a reciprocating linear motion.

Compressed air enters into the tube at one end of the piston and, hence, imparts force on the piston.

Like hydraulic cylinders, something forces a piston to move in the desired direction. The piston is a disc or cylinder, and the piston rod transfers the force it develops to the object to be moved.

Pneumatics are widely used in almost all applications today because it is a much faster process compared to hydraulics or mechanics.

Compared to hydraulics they are quieter, cleaner, and do not require large amounts of space for fluid storage.

Because the operating fluid is a gas, leakage from a pneumatic cylinder will not drip out and contaminate the surroundings, making pneumatics more desirable where cleanliness is a requirement.

Pneumatic Cylinder Movement Animation
Rod movement pneumatic cylinder
Pneumatic Cylinders

Types of Pneumatic Cylinders

Although pneumatic cylinders will vary in appearance, size and function, they generally fall into one of the specific categories shown below.

Single Acting Pneumatic Cylinder
Single acting pneumatic cylinder showing red color spring inside and only one air inlet

Single-acting cylinders (SAC) use the pressure imparted by compressed air to create a driving force in one direction (usually out), and a spring to return to the "home" position. More often than not, this type of cylinder has limited extension due to the space the compressed spring takes up. Another downside to SACs is that part of the force produced by the cylinder is lost as it tries to push against the spring.

Double acting pneumatic cylinders
Double acting pneumatic cylinder showing air inlet from both sides

Double-acting cylinders (DAC) use the force of air to move in both extend and retract strokes. They have two ports to allow air in, one for outstroke and one for instroke. Stroke length for this design is not limited, however, the piston rod is more vulnerable to buckling and bending.

Below is a free tool / software where you can find out the cfm that will be consumed by your pneumatic cylinder at the desired strokes per minute and the desired pressure you want to operate the same.

Please note that this is a solution for single acting cylinders therefore if you are using double acting cylinders you can simply double the cfm solution you get from this tool. 

Secondly this is designed assuming that you are located at Sea Level where the atmospheric pressure is highest at 14.7 PSIa. Therefore a compressor delivering higher cfm should be chosen for higher altitude sites.

Please contact us if you face any difficulties in using this tool.