Compressed Air Glossary: E to L

Efficiency Compression: The ratio of the theoretical work requirement to the actual work required to be performed on the gas within the cylinder.

Expanders: Engines or turbines in which gas expands, does work & undergoes a drop in temperature.

Filters: Devices that removes or separate the unwanted liquid & dust from air before it enters the compressor.

Fluidics: The general subject of instruments and controls dependent upon low rate flow of air or gas at low pressure as the operating medium.

Gas Bearings: These are load carrying machine which allows some movement in which the lubricant is air or some other gas.

Guide Vane: An adjustable stationary element that helps direct the flowing medium to the inlet of an impeller.

Gauge Pressure: Pressure determined by instruments or gauges.

Head, Adiabatic: The energy in foot pounds required to compress adiabatically and to deliver one pound of a given gas from one pressure level to another.

High Pressure air: Air which is compressed above 150 PSI.

Humidity Relative: The ratio of the partial pressure of the vapour to the vapour saturation pressure at the dry bulb temperature of the mixture.

Inlet Pressure: The pressure at the inlet flange of the compressor, measured in PSIG.

Intercooling: The removal of heat from gas or air between compressor stages.

Inducer: A curved inlet section on impeller.

Intercoolers: heat exchanger device which removes the heat of compression between the stages of compressor.

kPa: Equal to 1000 Pa.

Liquid Piston: A liquid piston compressor is a rotary compressor in which a vaned rotor revolves in an elliptical casing, with the rotor spaces sealed by a ring of liquid rotating with it inside the casing.

Load Time: Time period from when a compressor loads until it unloads.

Load/Unload Control: Control method that allows the compressor to run at full-load or at no load while the driver remains at a constant speed.