Unit 2: Pumps and Compressors UPDATED ACTUAL Questions and
CORRECT Answers
Question: (4-073-2.8) Which type of pump produces the greatest suction? Select one
Correct Answer: a. A volute centrifugal pump b. A centrifugal pump c. A regenerative pump d. A positive
displacement pump: D
Question: (4-073-2.1) Rotary pumps
Correct Answer: Select one: a. Are low-pressure pumps b. Must be primed before each use c. Are positive
displacement pumps d. Must use mechanical seals: C
Question: (4-074-5.4) Priming of a centrifugal pump refers to
Correct Answer: Select one: a. Removal of liquid from the pump b. Filling the pump casing with liquid
and removing the air c. Lifting the pump d. Closing the vent on the pump casing: B
Question: (4-075-3.1) The cooling water for an air compressor should be turned on
Correct Answer: Select one: a. When the compressor reaches operating temperature b. After starting the
compressor c. When the operating pressure is reached d. Before starting the compressor: D
Question: (4-074-2.1) A slight leakage is desired between the pump shaft and the packing in order to
Correct Answer: Select one: a. Prevent the ingress of air b. Prevent wearing of the wear rings c. Lubricate
the packing d. Prevent the pump from vapour locking: C
Question: (4-074-4.1) Shaft misalignment during operation of a pump can be caused by bearing wear,
thermal expansion and
Correct Answer: Select one: a. Shaft flexing b. Overloading the pump c. Loss of lubrication d. Improper
installation: A
Question: (4-075-2.8) Intercoolers should be equipped with
Correct Answer: Select one: a. Moisture separators b. Safety valves c. Baffles d. Automatic blow downs:
B
Question: (4-075-1.4) Which of the following air compressors gives two compression strokes per
crankshaft revolution? Select one
Correct Answer: a. Two-stage two cylinder double-acting compressor b. A two-stroke compressor c.
Single cylinder double acting compressor d. Two cylinder single stage double acting compressor: C
Question: (4-074-5.1) A inspection of a pump that is in operation should include
Correct Answer: Select one: a. Ensuring water flows freely from the packing b. Ensuring water drips from
the mechanical seals c. Checking that the suction and discharge pressures are correct d. Re-priming the
pump.: C
Question: (4-073-3.8) The capacity of a centrifugal pump
Correct Answer: Select one: a. Varies with discharge pressure b. Is fixed and can only be altered by
changing the impeller c. Should be varied by suction valve manipulation d. Can be altered by speed
variation only: A
Question: (4-075-2.1) An air compressor auxiliary which will decrease the power requirement is the
, Correct Answer: Select one: a. Receiver b. Diffuser c. Intercooler d. Aftercooler: C
Question: (4-075-1.9) Centrifugal compressors
Correct Answer: Select one: a. Are used for high pressure and low flow b. Could be of the multi-stage type
c. Must have a safety valve on the discharge when steam driven d. Require inlet and discharge valves: B
Question: (4-073-2.6) When a pump discharges into a vessel operating at 300 kPa, the 300 kPa is referred
to as
Correct Answer: Select one: a. Dynamic head b. Pressure head c. Discharge head d. Friction head: B
Question: (4-074-1.1) Wear rings in centrifugal pumps
Correct Answer: Select one: a. Are non-replaceable. b. Are installed on impellers c. Compensate for
misalignment of the impeller d. Are only found on high pressure pumps: B
Question: (4-074-1.2) Pump wear rings are installed on an impeller by threading, or
Correct Answer: Select one: a. Shrinking b. Welding c. Brazing d. Forging: A
Question: (4-073-3.2) Rotary pumps should be started with the discharge valve open because they are
_____ pumps. Select one
Correct Answer: a. Reciprocating b. Double-acting c. Positive displacement d. Regenerative: C
Question: (4-074-3.2) Proper priming and venting of a pump is important, especially if
Correct Answer: Select one: a. The medium being pumped is high temperature b. The medium being
pumped contains suspended solids c. A mechanical seal is used d. The pump has a stuffing box and lantern
ring: C
Question: (4-074-5.5) Pump priming is
Correct Answer: Select one: a. Done to centrifugal pumps with positive suction head b. Done with the
suction valve open c. Filling the pump with gas d. Done with the suction and discharge valve closed: B
Question: (4-073-3.16) A rotary pump
Correct Answer: Select one: a. Is silent in operation b. Has severe discharge pulsations c. Should be
equipped with a relief valve d. Is a dynamic pump: C
Question: (4-075-2.7) To reduce air temperature between stages, ____________ are used. Select one
Correct Answer: a. intercoolers b. aftercoolers c. receivers d. air dryers: A
Question: (4-073-3.11) When starting up a rotary pump you must be sure that the
Correct Answer: Select one: a. Discharge valve is closed b. Discharge valve is open c. Pump is filled with
air d. Pump suction valve is closed: B
Question: (4-073-2.5) The difference between static suction head and static discharge head is
Correct Answer: Select one: a. Total static head b. Static discharge head c. Static suction head d. Dynamic
head: A
Question: (4-073-2.3) Centrifugal pumps do not develop good suction lift because
Correct Answer: Select one: a. Atmospheric pressure is usually too low b. Their internal component
clearances are too high c. The speed is too low d. They favour pressure rather than volume: B
CORRECT Answers
Question: (4-073-2.8) Which type of pump produces the greatest suction? Select one
Correct Answer: a. A volute centrifugal pump b. A centrifugal pump c. A regenerative pump d. A positive
displacement pump: D
Question: (4-073-2.1) Rotary pumps
Correct Answer: Select one: a. Are low-pressure pumps b. Must be primed before each use c. Are positive
displacement pumps d. Must use mechanical seals: C
Question: (4-074-5.4) Priming of a centrifugal pump refers to
Correct Answer: Select one: a. Removal of liquid from the pump b. Filling the pump casing with liquid
and removing the air c. Lifting the pump d. Closing the vent on the pump casing: B
Question: (4-075-3.1) The cooling water for an air compressor should be turned on
Correct Answer: Select one: a. When the compressor reaches operating temperature b. After starting the
compressor c. When the operating pressure is reached d. Before starting the compressor: D
Question: (4-074-2.1) A slight leakage is desired between the pump shaft and the packing in order to
Correct Answer: Select one: a. Prevent the ingress of air b. Prevent wearing of the wear rings c. Lubricate
the packing d. Prevent the pump from vapour locking: C
Question: (4-074-4.1) Shaft misalignment during operation of a pump can be caused by bearing wear,
thermal expansion and
Correct Answer: Select one: a. Shaft flexing b. Overloading the pump c. Loss of lubrication d. Improper
installation: A
Question: (4-075-2.8) Intercoolers should be equipped with
Correct Answer: Select one: a. Moisture separators b. Safety valves c. Baffles d. Automatic blow downs:
B
Question: (4-075-1.4) Which of the following air compressors gives two compression strokes per
crankshaft revolution? Select one
Correct Answer: a. Two-stage two cylinder double-acting compressor b. A two-stroke compressor c.
Single cylinder double acting compressor d. Two cylinder single stage double acting compressor: C
Question: (4-074-5.1) A inspection of a pump that is in operation should include
Correct Answer: Select one: a. Ensuring water flows freely from the packing b. Ensuring water drips from
the mechanical seals c. Checking that the suction and discharge pressures are correct d. Re-priming the
pump.: C
Question: (4-073-3.8) The capacity of a centrifugal pump
Correct Answer: Select one: a. Varies with discharge pressure b. Is fixed and can only be altered by
changing the impeller c. Should be varied by suction valve manipulation d. Can be altered by speed
variation only: A
Question: (4-075-2.1) An air compressor auxiliary which will decrease the power requirement is the
, Correct Answer: Select one: a. Receiver b. Diffuser c. Intercooler d. Aftercooler: C
Question: (4-075-1.9) Centrifugal compressors
Correct Answer: Select one: a. Are used for high pressure and low flow b. Could be of the multi-stage type
c. Must have a safety valve on the discharge when steam driven d. Require inlet and discharge valves: B
Question: (4-073-2.6) When a pump discharges into a vessel operating at 300 kPa, the 300 kPa is referred
to as
Correct Answer: Select one: a. Dynamic head b. Pressure head c. Discharge head d. Friction head: B
Question: (4-074-1.1) Wear rings in centrifugal pumps
Correct Answer: Select one: a. Are non-replaceable. b. Are installed on impellers c. Compensate for
misalignment of the impeller d. Are only found on high pressure pumps: B
Question: (4-074-1.2) Pump wear rings are installed on an impeller by threading, or
Correct Answer: Select one: a. Shrinking b. Welding c. Brazing d. Forging: A
Question: (4-073-3.2) Rotary pumps should be started with the discharge valve open because they are
_____ pumps. Select one
Correct Answer: a. Reciprocating b. Double-acting c. Positive displacement d. Regenerative: C
Question: (4-074-3.2) Proper priming and venting of a pump is important, especially if
Correct Answer: Select one: a. The medium being pumped is high temperature b. The medium being
pumped contains suspended solids c. A mechanical seal is used d. The pump has a stuffing box and lantern
ring: C
Question: (4-074-5.5) Pump priming is
Correct Answer: Select one: a. Done to centrifugal pumps with positive suction head b. Done with the
suction valve open c. Filling the pump with gas d. Done with the suction and discharge valve closed: B
Question: (4-073-3.16) A rotary pump
Correct Answer: Select one: a. Is silent in operation b. Has severe discharge pulsations c. Should be
equipped with a relief valve d. Is a dynamic pump: C
Question: (4-075-2.7) To reduce air temperature between stages, ____________ are used. Select one
Correct Answer: a. intercoolers b. aftercoolers c. receivers d. air dryers: A
Question: (4-073-3.11) When starting up a rotary pump you must be sure that the
Correct Answer: Select one: a. Discharge valve is closed b. Discharge valve is open c. Pump is filled with
air d. Pump suction valve is closed: B
Question: (4-073-2.5) The difference between static suction head and static discharge head is
Correct Answer: Select one: a. Total static head b. Static discharge head c. Static suction head d. Dynamic
head: A
Question: (4-073-2.3) Centrifugal pumps do not develop good suction lift because
Correct Answer: Select one: a. Atmospheric pressure is usually too low b. Their internal component
clearances are too high c. The speed is too low d. They favour pressure rather than volume: B
