Chapter 9 Flashcards
To prevent surging, the flow through the compressor must not be allowed to fall below the ___________.
A) Surge point
B) Maximum volume
C) Rated point
D) Set point
E) Rated pressure
A
When starting a dynamic compressor:
A) Load up the compressor quickly
B) Ensure surge valves are wide open
C) Ensure suction and discharge valves are closed
D) Ensure surge valves are part open
E) Ensure surge valves are closed
B
A typical instrument air dryer maintains a dewpoint temperature of:
A) 0°C
B) -100°C
C) -40°C
D) -70°C
E) -10°C
D
In the variable speed control method, the compressor output is regulated by:
A) Only small receivers are available
B) A safety relief valve
C) A driver that can be throttled
D) Adjustment of clearance pockets
E) A rheostat
C
A method of unloading a reciprocating compressor is to:
A) Close the inlet vanes
B) Place a check valve in the discharge line
C) Hold the discharge valve closed
D) Hold the inlet valves in the open position
E) Hold the discharge valve open
D
The orientation of an air receiver may be:
- Vertical
- 45° from vertical
- Horizontal
- 30° for vertical
A) 2
B) 1, 3
C) 3
D) 1
E) 4, 2
B
An air compressor will require more power to compress the air if an intercooler is implemented.
A) True
B) False
B
____________ are provided for load control on smaller centrifugal air compressors.
A) Adjustable inlet vanes
B) Dummy piston
C) Moving and fixed blades
D) Variable frequency drive
E) Adjustable diffuser vanes
A
When starting up a compressor, ensure the manual block valves in the suction and discharge lines are:
A) Wide open (suction valve) and closed (discharge valve)
B) Both valves throttled back
C) Both closed
D) Closed (suction valve) and open (discharge valve)
E) Both wide open
E
The inlet pipe to the compressor must be:
A) Twice as large as the compressor intake
B) At least as large as the compressor intake
C) Larger than the compressor intake
D) At least as large as the compressor discharge
E) Smaller than the compressor intake
B
