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hi sir,
I am 7th semester mechanical engg student from GIMT, Azara, Guwahati. i need your help for our final year project. I would like to study on pneumatics and make a model on pneumatic arm. so , please send me a report on pneumatic arm or a brief idea on it so that I can proceed.
Please send me as early as possible.
Thank you
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Pneumatics
Pneumatics is a branch of technology, which deals with the study and application of use of pressurized gas to affect mechanical motion.
Pneumatic systems are extensively used in industry, where factories are commonly plumbed with compressed air or other compressed inert gases. This is because a centrally-located and electrically-powered compressor that powers cylinders and other pneumatic devices through solenoid valves is often able to provide motive power in a cheaper, safer, more flexible, and more reliable way than a large number of electric motors and actuators.
Pneumatics also has applications in dentistry, construction, mining, and other areas.
Examples of pneumatic systems and components
• Air brakes on buses and trucks
• Air brakes, on trains
• Air compressors
• Air engines for pneumatically powered vehicles
• Barostat systems used in Neurogastroenterology and for researching electricity
• Cable jetting, a way to install cables in ducts
• Compressed-air engine and compressed-air vehicles
• Gas-operated reloading
• Holman Projector, a pneumatic anti-aircraft weapon
• Lego pneumatics can be used to build pneumatic models
• Pipe organs:
o Electro-pneumatic action
o Tubular-pneumatic action
• Pneumatic actuator
• Pneumatic air guns
• Pneumatic cylinder
• Pneumatic Launchers, a type of spud gun
• Pneumatic mail systems
• Pneumatic motor
• Pneumatic tire
• Pneumatic tools:
o Jackhammer used by road workers
o Pneumatic nailgun
• Pressure regulator
• Pressure sensor
• Pressure switch
• Vacuum pump
Gases used in pneumatic systems
Pneumatic systems in fixed installations such as factories use compressed air because a sustainable supply can be made by compressing atmospheric air. The air usually has moisture removed and a small quantity of oil added at the compressor, to avoid corrosion of mechanical components and to lubricate them.
Factory-plumbed, pneumatic-power users need not worry about poisonous leakages as the gas is commonly just air. Smaller or stand-alone systems can use other compressed gases which are an asphyxiation hazard, such as nitrogen - often referred to as OFN (oxygen-free nitrogen), when supplied in cylinders.
Any compressed gas other than air is an asphyxiation hazard - including nitrogen, which makes up approximately 80% of air. Compressed oxygen (approx. 20% of air) would not asphyxiate, but it would be an extreme fire hazard, so is never used in pneumatically powered devices.
Portable pneumatic tools and small vehicles such as Robot Wars machines and other hobbyist applications are often powered by compressed carbon dioxide because containers designed to hold it such as soda stream canisters and fire extinguishers are readily available, and the phase change between liquid and gas makes it possible to obtain a larger volume of compressed gas from a lighter container than compressed air would allow. Carbon dioxide is an asphyxiant and can also be a freezing hazard when vented inappropriately.
Comparison to hydraulics
Both pneumatics and hydraulics are applications of fluid power. Pneumatics uses an easily compressible gas such as air or a suitable pure gas, while hydraulics uses relatively incompressible liquid media such as oil. Most industrial pneumatic applications use pressures of about 80 to 100 pounds per square inch (550 to 690 kPa). Hydraulics applications commonly use from 1,000 to 5,000 psi (6.9 to 34 MPa), but specialized applications may exceed 10,000 psi (69 MPa).
Advantages of pneumatics
• Simplicity of Design And Control
o Machines are easily designed using standard cylinders & other components. Control is as easy as it is simple ON - OFF type control.
• Reliability
o Pneumatic systems tend to have long operating lives and require very little maintenance.
o Because gas is compressible, the equipment is less likely to be damaged by shock. The gas in pneumatics absorbs excessive force, whereas the fluid of hydraulics directly transfers force.
• Storage
o Compressed Gas can be stored, allowing the use of machines when electrical power is lost.
• Safety
o Very low chance of fire (compared to hydraulic oil).
o Machines can be designed to be overload safe.
