PHEP CH7 Fans, Exhausters, and Air Compressors

Question 1

If all other factors are held constant, the volume of a dry gas decreases.

Answer 1

In direct proportion to an increase in its pressure

Question 2

Absolute pressure is equal to:

Answer 2

gauge pressure plus 14.7

Question 3

If 500 cubic inches of gas under a pressure of 15 psia is compressed to 20 cubic inches what will the new pressure be

Answer 3

375 psia

(Formula: P2/P1 = V1/V2

Question 4

The quantity and pressure of air discharged from a centifugal fan depends on the

Answer 4

ALL OF THE ABOVE

1. Size of the fan rotor
2. Speed of the fan rotor
3. Density of the air

Question 5

Increasing the speed of an unbalanced shaft will:

Answer 5

move the center of gravity further from the axis of rotation thereby increasing the unbalance

Question 6

Which of the following conditions would not normaly contribute to a reciprocating air compressor explosion?

Answer 6

Excessive compressed air demands

Question 7

Large reciprocating air compressors are generally unloaded while starting and stopping to

Answer 7

reduce the starting torque and permit more gradual stopping

Question 8

The temperature at which molecules of water vapor begin to condense upon the surface of objects as air is cooled is called the:

Answer 8

Dew point

Question 9

High outlet compressed ar temperatures could be caused by all of the following EXCEPT

Answer 9

Low oil level

Question 10

Air receivers are installed on all reciprocating air compressors to…

Answer 10

ALL OF THE ABOVE

1. Dampen pressure waves
2. Reduce pressure drops
3. Remove moisture or sludge