If you are reading this, I am officially welcoming you once again to my blog. A few days ago, I wrote about the hydraulic system which made me happy as I got lots of positive feedback o the simple explanation of the hydraulic systems.
If you read my conclusion on that post I stated that the hydraulic system has a sister in the pneumatic systems although both of hem work on fluids they are totally different. Today, I officially welcome you to the pneumatic system.
Have you ever boarded a big bus where only the driver has the control to open and close the door with a button? Many Nigerians in Lagos are familiar with the BRT or Lag bus. These busses are one of such and have you ever wondered how the system operates and with the push of a button the door opens and closes.
Quite fascinating right?
Today you would be learning about the systems responsible for that in the pneumatic systems.
The pneumatic systems.
Pneumatics which has its name from the Greeks can be viewed as the branch of applied science or engineering that makes use of gas or compressed air. The pneumatic systems, therefore, use air that is compressed as their source of power. These systems consist of several devices that sucks in the air compresses the air and use them for work this system may be an automatic or manual system.
The air used in the pneumatic systems usually have all their moisture removed to prevent corrosion. Gases such as nitrogen or carbon dioxide are used as gases in the pneumatic systems.
The pneumatic system is being used for several applications in the real world such as construction, mining and even dentistry. If you remember a post I made about elevators where I discussed the pneumatic elevators this is another application of the pneumatic system.
Let us sit tight as we dissect this system together but before we do that we cannot all but discuss how this system came to be.
How the pneumatic systems came to be
The pneumatic systems were the first to exist and they did long before the hydraulic systems were discovered. I guess the hydraulic system was an upgrade to the pneumatic systems due to their inability to produce more power.
The pneumatic systems have existed as far back as the first century which is a very long time ago. It was a Greek mathematician genius who wrote about his inventions which were powered by wind or steam.
Then a German in the name of Otto Guericke took off from where he stopped by inventing a vacuum pump in the sixteenth century. The vacuum pump
as we all know is a device that sucks air or gas from a space. The German proved the vacuum pumps could isolate the pairs of copper hemispheres using air pressure.
The field of the pneumatics has further grown to become a massive invention in the engineering field as it is now being used in several devices and equipment due to their simplicity, reliability, and safety.
The working principle of the pneumatic systems
part of a pneumatic system: img from from wikipedia under Creative Commons Attribution 3.0 License by Ingersoll Rand.
If you have watched power rangers, there is a basic explanation for the pneumatic systems just like there are five rangers that form the team there are also components or devices that come together to form any pneumatic system. Don’t forget, the power rangers can also form a single giant ranger this single giant ranger is taken as the pneumatic system.
And to form this system certain components with different functions come together to make up the pneumatic system. These devices need to be understood to know how any pneumatic systems operate and they include:
- The compressor
- The storage or reservoir
- Control valves
- A motor or actuator
For the pneumatic systems to work they need compressed air which is what I have been clamoring about since and to get this air compressed we need something to do that for us (i.e the compressor) and using the power in the compressed air requires another device to do that (i.e. the actuator). But to get the compressed air from where they are compressed down to where they are being stored and to where the energy in them is being used the air has to travel and it is done by moving through a circuit of pipes which are regulated by the control valves.
let us have a deep understanding of how these devices operate.
The compressors are a wonderful device which
I am sure you have heard about especially if you have read my post on refrigeration. Well, they have the same function which is to squeeze air, but these compressors in the pneumatic system are high powered compressors capable of compressing 7-10 times the atmospheric pressure if you think this is small that’s about 2 to 3 times the pressure in your car tyre.
Now, you are wowed?
The compression of air begins the cycle of the pneumatic systems. It basically does so by converting electrical energy to potential energy which is stored in the pressurized air.
The compressed or pressurized air coming from the compressors have to be kept. The purpose for this is for urbane flow from the compressor other than that, it helps the air to cool. The storage or reservoir has to be large enough to hold all the air being compressed by the compressor and the large surface area of the reservoir allows it to operate as a heat exchanger giving off its heat from the surface.
The control valves
Generally, control valves are used for flow regulation and this is also why they are applied here to regulate and control the direction and flow of the pneumatic system. One of the functions of the control valves is to provide steady downstream pressure in the airline regardless of the variation of upstream pressure. This means that the pressure in the storage is always kept higher than the system pressure.
The actuators are basically a mechanical device that moves, and it is found at the end of the pneumatic tool. Just like the ram moves up and down so does the actuators, they are responsible for carrying out the useful work for us. The actuators move in a to and fro (i.e. reciprocating) motion along a straight part or line. The actuators are empowered by the pistons which slide back and forth in the cylinder due to the supply and withdrawal of compressed air. You can now see how the compressed air turns its potential energy from the storage to kinetic energy of the actuators.
There are several equipment’s that work using this principle above and although the power developed by the pneumatic system cannot be compared to the hydraulic system. But it is very much powerful for carrying out some work in the automobile, dentist drill, polishers and many more devices.
Engineering application of the pneumatic system
The applications of the pneumatic systems cannot but be felt in various ways and applications in the real world from the engineering field to the everyday activities such as transport and production. The use in robotics is very much needed in some of their mechanisms.
Filter regulators, carwashes and test systems, food and beverage industries and dentistry have all benefited from the pneumatic systems. Automated systems too use the pneumatic systems. This shows that the pneumatic system has really made its way to many industries and its now being enjoyed in various fields despite its difference to the hydraulic system.
The pneumatic systems just like the hydraulic systems started from the Greeks and they both deal with the study of fluids to make mechanical work. The pneumatic systems, unlike hydraulics, make use of compressed air to make their work happen and this compressed air must have their moisture removed to prevent corrosion of metal parts.
The pneumatic systems consist of several devices which come together to make things work. The applications of the pneumatic systems cannot be ignored as they are applied and enjoyed in our day to day activities from the industrial world to the medical world. The pneumatic systems are not as powerful as the hydraulic therefore their applications cannot be the same but could be similar in some cases.
I hope you enjoyed reading this content? Stay tuned to my blog and thanks for reading.
For further reading, please get these books or follow these links.
explainthatstuff - pneumatics|rhmfp - pneumatics applications|sciencing.com - principles of pneumatic systems|pneumatics|more-control.com pneumatics|nptel|ispatguru basics of pneumatics and pneumatic-systems|wiki Pneumatics| Engineering Applications of Pneumatics and Hydraulics
by EurIng Ian C. Thrner