Millwright - 2nd Year: Positive Displacement
Pumps Exam Questions and Answers with
Verified Solutions | Latest Updated 2026
A positive displacement pump Pumping chamber
consists of a _______________.
Why is it important to incorporate Due to high pressure capabilities and the
relief valves on the discharge side need to
of protect the pump from damage
most positive displacement
pumps?
How are the majority of positive Self-priming
displacement pumps primed?
What is volumetric efficiency? The discrepancy between the actual
amount of
volumetric output and the theoretical
volumetric
output. (amount volume output over the
theoretical
volume output multiplied by 100)
Volumetric efficiency reduces as increases
system pressure
______________.
,A pump that utilizes a back-and- reciprocating pump
forth, straight-line motion to move
a
plunger, piston or diaphragm
inside a
cylinder or housing to provide a
pulsating pumping action is known
as a ______________.
What are the 3 types of 1. Plunger
reciprocating pumps? 2. Piston
3. Diaphragm
What is the difference between a The plunger pump's seal is stationary and
plunger pump and a piston pump? attached
to the cylinder housing while the piston
pump's
seal is connected to, and moves with the
piston
What are the advantages of 1. Low cost
plunger 2. Mechanical simplicity
and piston pumps? 3. High-pressure capability
What are disadvantages of piston 1. Cannot handle abrasives and
and plunger pumps? crystallizing liquids
2. Must not run dry as to not compromise
the
packing
3. Require a positive suction head or small
suction
lift
, What is a clearance volume on the space between the piston or plunger
piston and plunger pumps? when it is
fully extended and the cylinder head
What is a stroke? The distance moved by the plunger or
pistoin in a
cylinder.
How is the volume of the liquid Stroke x cross-sectional area of the
displaced by the plunger plunger
calculated?
A plunger pump can only be single
________________ -acting.
What is a single acting pump? A pump with only one discharge or
pumping stroke
per revolution
A _________ pump can also be piston
double-
acting.
What is a double-acting pump? A pump with 2 pumping strokes per cycle
Why does the return stroke Because the space the piston rod occupies
discharge less volume than the
outward stroke on a double-acting
pump.
Pumps Exam Questions and Answers with
Verified Solutions | Latest Updated 2026
A positive displacement pump Pumping chamber
consists of a _______________.
Why is it important to incorporate Due to high pressure capabilities and the
relief valves on the discharge side need to
of protect the pump from damage
most positive displacement
pumps?
How are the majority of positive Self-priming
displacement pumps primed?
What is volumetric efficiency? The discrepancy between the actual
amount of
volumetric output and the theoretical
volumetric
output. (amount volume output over the
theoretical
volume output multiplied by 100)
Volumetric efficiency reduces as increases
system pressure
______________.
,A pump that utilizes a back-and- reciprocating pump
forth, straight-line motion to move
a
plunger, piston or diaphragm
inside a
cylinder or housing to provide a
pulsating pumping action is known
as a ______________.
What are the 3 types of 1. Plunger
reciprocating pumps? 2. Piston
3. Diaphragm
What is the difference between a The plunger pump's seal is stationary and
plunger pump and a piston pump? attached
to the cylinder housing while the piston
pump's
seal is connected to, and moves with the
piston
What are the advantages of 1. Low cost
plunger 2. Mechanical simplicity
and piston pumps? 3. High-pressure capability
What are disadvantages of piston 1. Cannot handle abrasives and
and plunger pumps? crystallizing liquids
2. Must not run dry as to not compromise
the
packing
3. Require a positive suction head or small
suction
lift
, What is a clearance volume on the space between the piston or plunger
piston and plunger pumps? when it is
fully extended and the cylinder head
What is a stroke? The distance moved by the plunger or
pistoin in a
cylinder.
How is the volume of the liquid Stroke x cross-sectional area of the
displaced by the plunger plunger
calculated?
A plunger pump can only be single
________________ -acting.
What is a single acting pump? A pump with only one discharge or
pumping stroke
per revolution
A _________ pump can also be piston
double-
acting.
What is a double-acting pump? A pump with 2 pumping strokes per cycle
Why does the return stroke Because the space the piston rod occupies
discharge less volume than the
outward stroke on a double-acting
pump.
