Air Compressors Information
Air compressors are machines that compress and direct air for industrial applications. There are three basic types of air compressors: reciprocating, rotary screw, and centrifugal.
Reciprocating air compressors use pistons to compress the contents of an air cylinder and force them into a storage tank. These piston-driven air compressors are designed for intermittent use.
Rotary screw air compressors use twin screws instead of pistons to pressurize air. They are designed for continuous use and have a rated duty cycle of 100%.
Centrifugal air compressors are turbine engines that use rotating blades to produce high pressures. Typically, these air compressors are used in power generation and large-scale industrial applications.
Selecting air compressors requires an understanding of specifications and requirements.
Some air compressors are equipped with driers (dry compressors) which remove the condensation that is created during compression. Others include coolers that lower the temperature of the compressed air. Air compressors with paper or polyester filters that remove oil, dust, vapors, and other debris are also available.
Oil-free air is especially important in applications such as food processing and semi-conductor manufacturing, where as little as one part per billion (ppb) of oil is unacceptable. Click below to watch a video on the importance of using clean and dry compressed air.
Video Credit: Kaeser Compressors, Inc.
Size & Power
Smaller air compressors are usually powered by gasoline, diesel fuel, or single-phase electricity. Larger, commercial and industrial units often use three-phase power at 208 V, 230 V, or 460 V.
In terms of mobility, portable air compressors feature wheel, casters, or self-contained trailers. Vertical air compressors are designed for fixed mounting and require less floor space.
Air pressure is usually measured in pounds per square inch (psi).
Air flow is usually measured in standard cubic feet per minute (SCFM). Reciprocating air compressors can achieve air flows of up to 100 CFM. Rotary air compressors can reach 1500 CFM with a single stage and up to 2500 CFM with two stages. Centrifugal air compressors operate at levels greater than 1000 CFM.
With regard to air compressor efficiency, the Compressed Air and Gas Institute (CAGI) has developed a standard set of test criteria. Suppliers of air compressors can provide a CAGI data sheet with information about horsepower, efficiency, and expected energy consumption.
Small-scale devices are designed for pneumatic tools such as grinders, drills and nail guns. Manufacturing-scale products are used to drive punching and stamping equipment, power robotic tools, and convey parts. Air compressors that are designed for direct-use applications such as sandblasting and spray painting are also available.
AFM 85-30 - Operation & maintenance of air compressors
DEF STAN 02-315 - Air compressors
Read user Insights about Air Compressors
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Air Blow Guns
Air blow guns attach to air lines for the manual actuation and/or control of air discharge. They are used primarily for debris removal and purging, non-contact part cleaning and drying, and general laboratory or industrial applications.
Air cylinders are pneumatic linear actuators that are driven by a pressure differential in the cylinder's chambers. They may be single-acting (with a spring return) or double-acting.
Air Hose and Air Duct Hose
Air hose and air duct hose is used in pneumatic systems and controls, or as supply lines for pneumatic devices and tools.
Air motors are powered by compressed air. They operate at relatively high speeds in industrial and spark-prohibited applications.
Air Pressure Regulators
Air pressure regulators control pressure in air lines (usually adjustable) to remove fluctuations and maintain consistent pressure for pneumatic devices.
Air springs contain a column of air in an elastomeric bellow or sleeve to provide suspension, isolation, or actuation. Commonly found in vehicle suspension systems, perhaps in conjunction with a coil spring, they are also used to insulate vibration in machinery and as linear or angular actuators.
Air valves allow metered fluid flow in one or both directions. They are used in pneumatic circuits to regulate the rate of activation or exhaust of cylinders and other pneumatic devices.
Compressed Air Dryers
Compressed air dryers utilize technologies such as refrigeration, desiccant adsorption, and membrane filtration to remove contaminants, particularly water, from the air.
Compressed Air Filters
Compressed air filters are used to remove water, oil, oil vapor, dirt, and other contaminants from a compressed air supply.