Pneumatics can be described as the way of transferring mechanical energy from one point to another using air pressure. Gas laws describe the volume-temperature-pressure relationships for gases under a variety of conditions. Boyle's Law states that the absolute pressure of a contained gas is inversely proportional to its volume provided its temperature remains constant. Gay-Lussac's Law states that the absolute pressure of a confined gas is proportional to its temperature provided its volume remains constant. Charle's Law states that the volume of a confined gas is proportional to its temperature provided its pressure remains constant.
A pneumatic system is made out of several key components. The compressor unit is made out of one or more cylinders, with pistons fitted inside, which generate pressure on the air volume, reducing it. The compressor is connected to the air receiver through a discharge line that allows the air to flow only in one way. The air tank is connected to a pressure gauge which shows the pressure inside the tank, and an exhaust valve is used to release the compressed air outwards. Devices that need to be powered by compressed air are connected to the exhaust valve.
The advantages of pneumatics are that it can be used in a variety of applications and can deliver great amounts of power. Among the disadvantages are the costs of the equipment, which may be greater, compared to other power systems. Also, the high pressure air might be dangerous in the event of a failure.
Compressed air is used for a variety of applications from every day object to space technology. The automotive industry also uses pressurized air for the shock absorbers and brake systems. Another use of compressed air is for controlling satellites and spaceships outside Earth's atmosphere.
If working in hazardous environments, pneumatic tools should be considered since they only use air, and therefore are not affected by humidity, unlike electrical tools or flammable substances.