What are air cylinders?
Air cylinders, also known as Pneumatic cylinders or Pneumatic drives, are mechanical devices that are used produce force by utilizing compressed air as a fuel to move objects of various sizes. A piston exists in the pneumatic cylinder which requires compressed air in order to move, as the piston moves, a force is created that helps the object in target to move.
Most of the times, a pneumatic system is preferred as it doesn’t require big space to fit, don’t make much noise & are easier to manage as they are cleaner compared to hydraulic systems.
Types of Pneumatics cylinders:
Single acting Cylinder:
Single-acting cylinders create force driven by the compressed air in a single direction only, most of the time, outwards, after that they return back to the original position. This is done with the help of an internal spring that is placed inside the piston and it automatically springs back the original position it was originally.
In other cases where instead of an internal spring, some other sort of external pressure or external spring is used to pull back the piston to its original position. Some force is lost during this process, as its lost while the spring is returning to its initial point. Let’s take a Pneumatic Cylinder Festo
specification example:
Single Acting cylinder:
- Generally comes in diameters of 12, 16, 20, 25 up to 100mm
- Has a stroke length of 1 to 25mm
- Gives out a force of 59 to 4510N
- Have fixed cushions in the cylinder
- It’s generally compact
- The cylinder tube is made out of steel
- The piston rod is made of stainless steel
- ISO 21287
Double Acting Cylinder:
Pneumatic Double acting cylinder works a bit different compared to a single acting one. In this type, there are two places available on either side of the cylinder that help the air to get in and move the cylinder in either direction.
There are no limitations when it comes to the length of the strokes but there is a possibility of the piston to bend as its being pressured from both sides.
Let’s have a look at the important specifications of a double acting cylinder:
Festo ISO Cylinder Model: DSBC-32-25-PPVA-N3
- It works on double acting mode of operation using compressed air as mode of operation.
- The diameter of its piston in 32mm with a stroke of 25mm.
- It contains Pneumatic cushions at both the ends which help slow down the piston towards the end of a stroke. They can help stop any damage that might happen when the cushion is moving at a high speed and need to be stopped suddenly.
- The position is detected through a proximity sensor.
- The body material is made out of Aluminium die cast or aluminium Alloy.
- The advance stroke gives out 483 N at 6 bar pressure & 415 N at the return stroke at the same pressure.
- Ambient temperature for this cylinder rangers from -20°C to 80°C at max.
- The piston material is made out of high alloy steel.
- The cylindrical aluminium barrel is made out of anodised aluminium alloy.
Telescoping Cylinder:
This is a type of cylinder that can work both modes that is single acting and double acting. These cylinders have the capacity for long strokes compared to the other two types. These are also referred to as a multi-stage telescopic cylinder.
They work in three different types:
- Single acting
- Double acting
- Single & double acting combination
Telescopic cylinders, in general, are used in heavy construction machines with the same speed or same force. These are generally built when you require long travel distances from a single compact are. But when it comes to pneumatics, only lighter units are used to power with compressed air, as that is when a pneumatic system works in an optimal way.
