Pneumatics

Pneumatics is the use of compressed air for mechanical motion. It has many uses.^[1]

Pneumatic transfer systems are employed in many industries to move powders and devices. Pneumatic devices are also used where electric motors cannot be used for safety reasons, such as deep in a mine where explosive dust or gases may be present.

Examples of pneumatic tools

Pneumatic drill (jackhammer) used by road workers
Pneumatic nailgun
Pneumatic switches
Pneumatic actuators
Air compressors
Vacuum pumps
Barostat systems used in Neurogastroenterology and for researching

electricity

Cable Jetting - a way to install cables in ducts
Pneumatic mail systems
Air brakes on buses, trains, and trucks

Comparison to Hydraulics

Both pneumatics and hydraulics are applications of fluid power. Pneumatics uses air, which is compressible, while hydraulics uses relatively incompressible liquid media such as oil or water.

Advantages of pneumatics

The working fluid is very light in weight so supply hoses are not heavy.

Because the working fluid is (mostly) just air, there is usually no need for a return line for the working fluid and leaks of the working fluid tend not to be messy.

Because air is compressible, the equipment is less likely to be damaged by shock. The air in pneumatics absorbs excessive force, whereas the fluid of hydraulics directly transfers force.

Advantages of hydraulics

Higher energy density owing to the much higher working pressures usually employed.

The hydraulic working fluid is basically incompressible, leading to a minimum of spring action. When hydraulic fluid flow is stopped, the slightest motion of the load releases the pressure on the load; there is no need to "bleed off" pressurised air to release the pressure on the load...

References

↑ In dentistry applications, pneumatic drills are lighter, faster, and simpler than an electric drill of the same power rating (because the compressor, is separate from the drill and pumped air is capable of rotating the drill bit at extremely high rpm).

Other websites

www.pneumatics.be - didactic website - for students - how pneumatics works
U.S. Department of Energy Archived 2006-06-25 at the Wayback Machine - Improving Compressed Air System Performance
Fluid Power Educational Foundation Archived 2020-07-08 at the Wayback Machine - Advancing and Supporting Hydraulic & Pneumatic Education
Pneumatics Glossary Archived 2013-03-15 at the Wayback Machine - Glossary of Pneumatic Terms

[1] In dentistry applications, pneumatic drills are lighter, faster, and simpler than an electric drill of the same power rating (because the compressor, is separate from the drill and pumped air is capable of rotating the drill bit at extremely high rpm).

[1]