An air compressor is a device that converts power (using a power motor, diesel or gasoline engine, etc.) into potential energy placed in pressurized air (i.e., compressed air). By one of the methods, an air compressor forces an increasing number of air right into a storage tank, increasing the pressure. When the tank’s pressure reaches its engineered upper limit, the air compressor shuts off. The compressed air, then, is held in the tank until called into use. The energy within the compressed air can be utilised for a number of applications, using the kinetic energy of the air since it is released and the tank depressurizes. When tank pressure reaches its lower limit, the air compressor turns on again and re-pressurizes the tank. An air compressor should be differentiated from a pump since it works for just about any gas/air, while pumps focus on a liquid.
Positive-displacement compressors work by forcing air in a chamber whose volume is decreased to compress the air. After the maximum pressure is reached, a port or valve opens and air is discharged in to the outlet system from the compression chamber. Common types of positive displacement compressors are
Piston-type: air compressors utilize this principle by pumping air into an air chamber through the application of the frequent motion of pistons. They use one-way valves to steer air into and out of a chamber whose base contains a moving piston. When the piston is on its down stroke, it draws air in to the chamber. When it’s on
Technical Illustration of a two-stage air compressor
its up stroke, the charge of air is forced out and right into a storage tank. Piston compressors generally fall into two basic categories, single-stage and two-stage. Single stage compressors usually fall in to the fractional through 5 horsepower range. Two-stage compressors normally fall
Technical Illustration of a lightweight single-stage air compressor
in to the 5 through 30 horsepower range. Two-stage compressors provide greater efficiency than their single-stage counterparts. Because of this, these compressors are the most frequent units within the tiny business community. The capacities for both single-stage and two-stage compressors is normally provided in horsepower (HP), Standard Cubic feet each and every minute (SCFM)* and Pounds per Square Inch (PSI). *To a smaller extent, some compressors are rated in Actual Cubic Feet each and every minute (ACFM). Still others are rated in Cubic Feet each and every minute (CFM). Using CFM to rate a compressor is incorrect since it represents a flow rate that’s independent of a pressure reference. i.e. 20 CFM at 60 PSI.
Rotary screw compressors: use positive-displacement compression by matching two helical screws that, when turned, guide air right into a chamber, whose volume is decreased as the screws turn.
Vane compressors: use a slotted rotor with varied blade placement to steer air right into a chamber and compress the quantity. This sort of compressor provides a set level of air at high pressures.