Air Compressors and Pumps Flashcards
(295 cards)
Piece of machinery that draws in ambient air, pressurises this air, and delivers in to a holding tank (receiver) or to its end user
Air compressor
7 basic components of an air compressor system
Lubricating system Driving connections Cooling system Compressor element Driving power Control components Air receiver
Three types of driving power
Electrical motors
Internal combustion engine
Reduction gear
Three types of drive connections
Close-coupled
V-belts and pulleys
Reduction gears
When the compressor and the driving unit are mounted on the same shaft, they are ___
Close-coupled
Close-coupling is usually restricted to ___
Small capacity compressors that are driven by electric motors
Sometimes used to join the driving unit to the compressor when the speed of the compressor and the speed of the driving unit are the same
Flexible couplings
Drive connection commonly used with small, low pressure, and some medium-pressure motor driven compressors
V-belts and pulleys
Three types of compressing elements
Centrifugal
Rotary compressors/blowers
Reciprocating
Continuous flow compressor in which the rotating bladed wheels impart a high velocity to the air; the velocity energy developed raises the static pressure of the air without use of valves as it is passed through a diffuser
Centrifugal
Positive displacement compressor in which the displacing and compressing elements are interacting lobes, screws, or eccentrically oriented vanes rotating within housings fitted with suction and discharge ports
Rotary compressors/blowers
Positive displacement compressor in which the displacing and compressing elements are pistons moving back and forth in a cylinder fitted with suction and discharge valves
Reciprocating
Most widely used compressors
Reciprocating compressors
Low operating pressure
150 psi or less
Medium operating pressure
151 to 1000 psi
High operating pressure
Above 1000 psi
Ship’s Service Air
150 psi or less
Start Air, or Diesel Start Air
151 to 1000 psi
SSA
Ship’s Service Air
SA
Start Air
DSA
Diesel Start Air
Total compression form atmospheric pressure to the final discharge pressure, is accomplished in one stroke of the piston
Single-stage compressor
In a two-stage compressor, in ___ of the crankshaft, a compression cycle is completed
One revolution
Cylinder designs very widely depending upon ___
The number of stages of compression required