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Improving Compressed Air System Performance


Quiz Questions

1.What is the use of compressor?
To increase the pressure of the gas.
To decrease the pressure of the gas.
To maintain the pressure of the gas.
None of these
2. The inherent characteristic of centrifugal air compressor is that as system pressure decreases the compressor‘s flow capacity decrease.
True
False
3.What is the oldest method of driving compressors?
Steam Engine
Turbine
Both a & b
None of these
4.Dense-phase transport is used to transport solids in a(n) ——————————format.
individual
batch
Both a & b
None of these
5.The term vacuum generation describes applications where compressed air is used in conjunction with a venture, educator or ejector to generate a negative- pressure mass flow.
True
False
6.

Total leakage (percentage) can be calculated as follows: where: T = on-load time (minutes)

t = off-load time (minutes)

Leakage (%)= [(T x 100)/(T*t)]
Leakage (%) = [(T x 100)/(T+t)]
Leakage (%) = [(T x 100)/(T-t)]
None of these
7.While cooling the temperature of the lubricant injected into the compression chamber is generally controlled directly to a minimum of
1600 Fahrenheit.
1500 Fahrenheit.
1400 Fahrenheit.
1300 Fahrenheit.
8.Rotary screw compressors may be air or water cooled.
True
False
9.Depending on air system demand the control range can be anywhere from
1 to 20 psi.
2 to 20 psi.
1 to 30 psi.
2 to 30 psi.
10.What is critical temperature?
The highest temperature at which well-defined liquid and vapour states exist.
Sometimes it is defined as the highest temperature at which it is possible to liquefy or gas by pressure alone.
Both a & b
None of the above
11.Excessive pressure drop will result in
poor system performance and excessive energy consumption.
efficient system performance and less energy consumption.
poor system performance and less energy consumption.
efficient system performance and excessive energy consumption.
12.Centrifugal air compressors are
high speed rotating machines.
low speed rotating machines.
medium speed rotating machines.
None of the above
13.Aerating, agitating, oxygenating or percolating liquid with compressed air is defined as
open blowing.
sparging.
aspirating.
atomizing.
14.The typical applications of cabinet cooling are programmable controllers, line control cabinets, motor control cabinets and relay pads.
True
False
15.Leaks occur most often at ___________.
joints and connections.
only joints.
only connections.
None of these
16.Which compressor is usually limited to higher volume industrial applications?
Centrifugal compressor
Simple and double acting compressor
Rotary compressor
None of the above
17.Valves are used to_______________.
direct the flow
prevent flow
Both a & b
None of the above
18. Seals in compressors are used as________________.
maximize leakage
minimise leakage
increase the flow of the fluid
None of the above
19.Which element is measured in order to estimate the annual electricity consumption of a compressed air system?
Pressure
Power
Temperature
Baseline
20. ___________ detection and repair is an important part of any maintenance program.
Compressor
Leak
Both a & b
None of these