PHEP Ch.7

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 pressure be ?
P2/p1= v1/v2

Answer 3

375 psia

Question 4

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

Answer 4

-size of the rotor
-speed of the fan rotor
-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 normally contribute to be 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 of which molecules of water vapor begin to condense up on the surface of objects as air is cooled, is called the

Answer 8

Dewpoint

Question 9

High outlet compressed air 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

-dampen pressure waves
-reduce pressure drops
-remove moisture or sludge