ABSA: 4th Class Part B - Comprehensive Exam 5
questions with accurate answers
A boiler boil-out
Select one:
a. is done at 1.5 times the maximum allowable working pressure.
b. is done before curing the refractory.
c. must be done annually.
d. is done with an alkaline solution. Ans✓✓✓ d
A centrifugal pump consists of:
Select one:
a. A pulsating disc
b. Sliding vanes
c. Gears rotating in a housing
d. An impeller surrounded by a casing Ans✓✓✓ d
A closed cycle gas turbine:
Select one:
a. Burns fuel with spent exhaust gas.
b. Recycles the same working fluid
,c. Is the most common type of gas turbine
d. Does not need a combustion chamber Ans✓✓✓ b
A cold weather cooling tower bypass valve should not be fully closed
until the temperature reaches:
Select one:
a. about 27°C
b. +5°C
c. the point at which drift stops
d. the compressor setpoint Ans✓✓✓ a
A high stack temperature in a hot oil heater may indicate:
Select one:
a. Inadequate combustion air
b. A tube failure
c. Excessive oil flow
d. Improper fuel-air ratio Ans✓✓✓ b
A hot water boiler operating control (Aquastat) may be a pressure
switch:
Select one:
,a. that is normally open
b. that responds to the expansion and contraction of boiler water
c. operated by a filled system thermometer
d. that is sensitive to steam pressure Ans✓✓✓ c
A inspection of a pump that is in operation should include:
Select one:
a. Re-priming the pump.
b. Checking that the suction and discharge pressures are correct
c. Ensuring waterflowsfreely from the packing
d. Ensuring water drips from the mechanical seals Ans✓✓✓ b
A material that is commonly used as a solid lubricant is:
Select one:
a. Tallow
b. Lime
c. Molybdenum disulfide
d. Sodium carbonate Ans✓✓✓ c
A mercury switch bulb is under high vacuum and contains inert gas:
Select one:
, a. So the contacts will not overheat
b. To decrease electrical resistance
c. To keep the mercury from oxidizing
d. So it will not explode Ans✓✓✓ c
A modulating control steam heating boiler:
Select one:
a. Is always fully automatic
b. Will have a narrow operating pressure range
c. Maintains a steadier boiler pressure than multi-position control
d. Will have a constant combustion air flow rate Ans✓✓✓ c
A safety control designed to protect the chiller from freezing is the:
Select one:
a. Chilled water flow switch
b. Motor demand limiter
c. Low oil pressure shut down switch
d. Vane closed switch Ans✓✓✓ a
A shell type bearing:
questions with accurate answers
A boiler boil-out
Select one:
a. is done at 1.5 times the maximum allowable working pressure.
b. is done before curing the refractory.
c. must be done annually.
d. is done with an alkaline solution. Ans✓✓✓ d
A centrifugal pump consists of:
Select one:
a. A pulsating disc
b. Sliding vanes
c. Gears rotating in a housing
d. An impeller surrounded by a casing Ans✓✓✓ d
A closed cycle gas turbine:
Select one:
a. Burns fuel with spent exhaust gas.
b. Recycles the same working fluid
,c. Is the most common type of gas turbine
d. Does not need a combustion chamber Ans✓✓✓ b
A cold weather cooling tower bypass valve should not be fully closed
until the temperature reaches:
Select one:
a. about 27°C
b. +5°C
c. the point at which drift stops
d. the compressor setpoint Ans✓✓✓ a
A high stack temperature in a hot oil heater may indicate:
Select one:
a. Inadequate combustion air
b. A tube failure
c. Excessive oil flow
d. Improper fuel-air ratio Ans✓✓✓ b
A hot water boiler operating control (Aquastat) may be a pressure
switch:
Select one:
,a. that is normally open
b. that responds to the expansion and contraction of boiler water
c. operated by a filled system thermometer
d. that is sensitive to steam pressure Ans✓✓✓ c
A inspection of a pump that is in operation should include:
Select one:
a. Re-priming the pump.
b. Checking that the suction and discharge pressures are correct
c. Ensuring waterflowsfreely from the packing
d. Ensuring water drips from the mechanical seals Ans✓✓✓ b
A material that is commonly used as a solid lubricant is:
Select one:
a. Tallow
b. Lime
c. Molybdenum disulfide
d. Sodium carbonate Ans✓✓✓ c
A mercury switch bulb is under high vacuum and contains inert gas:
Select one:
, a. So the contacts will not overheat
b. To decrease electrical resistance
c. To keep the mercury from oxidizing
d. So it will not explode Ans✓✓✓ c
A modulating control steam heating boiler:
Select one:
a. Is always fully automatic
b. Will have a narrow operating pressure range
c. Maintains a steadier boiler pressure than multi-position control
d. Will have a constant combustion air flow rate Ans✓✓✓ c
A safety control designed to protect the chiller from freezing is the:
Select one:
a. Chilled water flow switch
b. Motor demand limiter
c. Low oil pressure shut down switch
d. Vane closed switch Ans✓✓✓ a
A shell type bearing:
