EPRI EXAM PREP QUESTIONS
WITH CORRECT ANSWERS!!
What do pumps do?
Move a volume of water form a lower pressure to a higher pressure.
What are the important pumps in a BWR called?
Recirc Pumps
How does a positive displacement pump work? How do you control flow?
Transfers a given quantity of fluid per shaft revolution or plunger stroke. To control flow,
you must change operating speed, a length of stroke, or a bypass valve.
How does a centrifugal pump work? How do you control flow?
Imparts a kinetic energy to the liquid being pumped and then transforms this kinetic energy
into flow and pressure. To control flow you must vary system discharge resistance usually with
a control valve or by varying operating speed.
What is unique about a PDP?
Will produce the same flow at a given speed no matter the discharge pressure. Often referred
to as a "constant flow machine".
What happens if a valve downstream of a PDP closes?
The pump can continue pumping until equipment failure occurs.
What are PDP pumps commonly used for?
Make up flow, CVCS, and Hydrostatic pressure tests.
What are the types of PDP's?
, Reciprocating Pumps
Rotary Pumps -
Gear
Screw
Vane
Flexible Member
What are reciprocating pumps most useful for and what are the moving components?
High pressure, low flow due to the high head capacity
1. Piston
2. Plunger
3. Diaphragm
Example: Main Turbine Hydraulic System
What is single acting and double acting?
Single acting - liquid is discharged on forward stroke
Double acting - liquid is discharged on the forward and return stroke
What may be used to dampen pulsating flow characteristics around reciprocating pumps?
What is required?
Dampeners or accumulators
Discharge relief valves
How does a gear pump work? What system are prime users?
Fluid is carried between the gear teeth and displaced when they mesh. Hydraulic and
lubricating systems
How does a screw pump work? What is it good at pumping?
Fluid is carried in spaces between screw threads. The power rotor drives the two idler rotors.
Oil and other viscous fluids.
How does a vane pump work? What are they for?
WITH CORRECT ANSWERS!!
What do pumps do?
Move a volume of water form a lower pressure to a higher pressure.
What are the important pumps in a BWR called?
Recirc Pumps
How does a positive displacement pump work? How do you control flow?
Transfers a given quantity of fluid per shaft revolution or plunger stroke. To control flow,
you must change operating speed, a length of stroke, or a bypass valve.
How does a centrifugal pump work? How do you control flow?
Imparts a kinetic energy to the liquid being pumped and then transforms this kinetic energy
into flow and pressure. To control flow you must vary system discharge resistance usually with
a control valve or by varying operating speed.
What is unique about a PDP?
Will produce the same flow at a given speed no matter the discharge pressure. Often referred
to as a "constant flow machine".
What happens if a valve downstream of a PDP closes?
The pump can continue pumping until equipment failure occurs.
What are PDP pumps commonly used for?
Make up flow, CVCS, and Hydrostatic pressure tests.
What are the types of PDP's?
, Reciprocating Pumps
Rotary Pumps -
Gear
Screw
Vane
Flexible Member
What are reciprocating pumps most useful for and what are the moving components?
High pressure, low flow due to the high head capacity
1. Piston
2. Plunger
3. Diaphragm
Example: Main Turbine Hydraulic System
What is single acting and double acting?
Single acting - liquid is discharged on forward stroke
Double acting - liquid is discharged on the forward and return stroke
What may be used to dampen pulsating flow characteristics around reciprocating pumps?
What is required?
Dampeners or accumulators
Discharge relief valves
How does a gear pump work? What system are prime users?
Fluid is carried between the gear teeth and displaced when they mesh. Hydraulic and
lubricating systems
How does a screw pump work? What is it good at pumping?
Fluid is carried in spaces between screw threads. The power rotor drives the two idler rotors.
Oil and other viscous fluids.
How does a vane pump work? What are they for?