Pneumatics and its origin

Pneumatics (from Greek πνεῦμα pneuma "wind, breath") is the branch of engineering that uses gas or compressed air.Pneumatic systems used in industry are usually powered by compressed air or compressed inert gas.A centrally located electric compressor powers cylinders, air motors, pneumatic actuators, and other pneumatic equipment.Pneumatic systems controlled by manual or automated solenoid valves are chosen when they offer a lower cost, more flexible or safer alternative to electric motors and hydraulic actuators.Pneumatics also have applications in dentistry, construction, mining and other fields

Gases used in pneumatic systems

Pneumatic systems in stationary installations such as factories use compressed air because a sustainable supply can be achieved by compressing the atmosphere.The air is usually dehydrated and a small amount of oil is added at the compressor to prevent corrosion and lubricate the mechanical parts.Users of factory installed pneumatic power do not have to worry about toxic leaks as the gas is usually just air.Any compressed gas other than air is a suffocation hazard including nitrogen, which is 78 percent air. Compressed oxygen (about 21% of air) does not suffocate, but is not used in pneumatic equipment because it is a fire hazard, is more expensive, and has no performance advantage over air.Smaller or self-contained systems may use other compressed gases that present a choking hazard, such as nitrogen - often referred to as OFN (oxygen-free nitrogen) when supplied in cylinders.

Portable pneumatic tools and small vehicles, such as Robot vs. Machine and other hobbyist applications, are often powered by compressed carbon dioxide because containers designed to hold it, such as soda cans and fire extinguishers, are readily available, and liquids and gases are separated between them.The phase change between them makes it possible to obtain a larger volume of compressed gas than is required for compressed air from a lighter container.Carbon dioxide is a smothering agent and may pose a freezing hazard if not vented properly.

Origin

The origins of aerodynamics can be traced back to the first century AD, when the ancient Greek mathematician Hero of Alexandria wrote that his inventions were powered by steam or wind.The German physicist Otto von Guericke (1602-1686) developed the idea further.He invented the vacuum pump, a device that sucks air or gas out of attached containers.He demonstrated that a vacuum pump uses air pressure to separate pairs of copper hemispheres.The world of aerodynamics has changed dramatically over the years. It has grown from a small handheld device to a large machine with multiple parts serving different functions.

Comparison with hydraulic systems

Both pneumatics and hydraulics are applications of fluid power. Pneumatics use an easily compressible gas, such as air or a suitable pure gas, while hydraulics use a relatively incompressible liquid medium, such as oil.Most industrial pneumatic applications use pressures of approximately 80 to 100 psi (550 to 690 kPa). Hydraulic applications typically use 1,000 to 5,000 psi (6.9 to 34.5 MPa), but special applications may exceed 10,000 psi (69 MPa).