TPC 309 Basic Pneumatics Flashcards
In compressed air systems, what provides force that performs work?
Compressed Air
What is the formula for work?
Work = Force * Distance
What is Charles’ Law?
Gas pressure inside a sealed container is proportional to the gas temperature.
How does force amplification not violate the work formula?
Force amplification = Distance Reduction
Air flowing through narrowed cross section does what to air speed and pressure?
Air Speed increases, Air Pressure Decreases
What type of compressor is a reciprocating compressor?
A positive displacement type compressor
What opens the inlet in a reciprocating compressor?
Atmospheric pressure overcoming the vacuum inside the compressor chamber
What is the purpose of a compressor intercooler?
Reduce the power requirements of the compressor
(When air is compressed, it heats up expanding the air, once it is cooled it can be further compressed without overheating the compressing chamber [causing leaks] and allows moisture to condense out of the compressed air)
Purpose of Lubrication in a compressor
To improve cooling
Advantage of unloading a compressor
Run without delivering air (so that the compressor can get up to temp)
What pressure can a single stage vane compressors achieve?
up to 50 PSI
What is the typical speed of a rotary screw compressor.
3K to 12K RPM
What is the general purpose of an impeller type compressors
High air volume, low air pressure
What is a downside of a centrifugal compressor?
Requires more power.
How to reduce air output of a centrifugal compressor?
Speed variations
Does have trouble with large reductions to speed, because compressor efficiency drops drastically.
Does compressed air carry more or less water vapor?
Compressed air carry less water vapor (Water is in-compressible)
Most common way to remove water from compressed air
Cooling the air
Where are water cooled aftercoolers used?
For large compressors that is on >10 hours a day
What does a desiccant do?
Absorb Moisture
Main Purpose of a compressed air receiver?
Maintain Pressure at peak demand.