compressed air, air whose volume has been decreased by the application of pressure. Air is compressed by various devices, including the simple hand pump and the reciprocating, rotary, centrifugal, and axial-flow compressors compressor, machine that decreases the volume of air or other gas by the application of pressure. Compressor types range from the simple hand pump and the piston-equipped compressor used to inflate tires to machines that use a rotating, bladed element to achieve
..... Click the link for more information. . Compressed air exerts an expansive force that can be controlled and used in various devices including tires, air brakes, caissons, and diving suits. As a source of power it is used to operate pneumatic tools pneumatic tool (n

măt`ĭk), instrument activated by air pressure.
..... Click the link for more information. , e.g., pneumatic hammers and drills and spraying equipment. It is widely employed for cleaning dust and dirt out of mechanical equipment. It is used also in mining, tunneling, and the manufacture of explosives, since it is not a fire hazard. Compressed air is in readily available supply and is easily stored and transported.

compressed air

Air reduced in volume and held under pressure. Force from compressed air is used to operate numerous tools and instruments, including rock drills, train brake systems, riveters, forging presses, paint sprayers, and atomizers. Bellows have been used since the Early Bronze age to provide air for smelting and forging. The 20th century witnessed a large increase in the use of compressed-air devices. The introduction of jet engines for military and passenger aircraft stimulated the use and improvement of centrifugal and axial-flow compressors. Digital-logic pneumatic-control components (developed in the 1960s) can be used in power and control systems (see pneumatic device).