Process Technology Equipment Chapter 6 Pumps
11. What type of loads are parallel to the shaft?
A. Axial
B. Radial
C. Mechanical
D. Stationary
12. What is a measure of a pump’s ability to move liquid through the system?
A. Head
B. Total head
C. Discharge static head
D. Suction static head
13. What is the vertical distance between the centerline of a pump and the surface
of the liquid on the discharge side of the pump?
A. Head
B. Total head
C. Discharge static head
D. Suction static head
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14. Which of the following is a cause of no or low discharge flow?
A. Increased head
B. Open valves
C. Line blockage
D. System design
15. Which of the following is contained in the manufacturer’s supply performance
pump curve for centrifugal pumps?
A. Head
B. Horsepower
C. NPSH required
D. All of the above
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16. How is NPSH calculated with regards to the performance pump curve?
A. NPSH is the maximum flow rate at zero flow.
B. NPSH is the ratio of the liquid horsepower to the brake horsepower.
C. NPSH is normally based on evaluation with water.
D. NPSH is calculated using atmospheric pressure, vapor pressure, liquid height, and
pressure drop.
17. If the specific gravity of the material is greater than 1.0, what is true of
horsepower?
A. Less horsepower is required.
B. More horsepower is required.
C. No horsepower is required.
D. Horsepower will depend on the viscosity of the liquid.
Process Technology Equipment Chapter 6 Pumps
18. What problem can occur when there is improper lubrication?
A. Leakage
B. Cavitation
C. Overheating
D. Overpressurization
19. What problem can occur where the pump shaft exits the pump casing?
A. Leakage
B. Cavitation
C. Overheating
D. Overpressurization
20. Which of the following is a cause for pump shutdown?
A. Overspeed trip
B. Power failure
C. Motor trip-out
D. All of the above
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23. What can cause vibration?
A. High temperature
B. Worn bearings
C. Low pump speed
D. All of the above
24. Which of the following should process technicians do when monitoring and
maintaining pumps?
A. Monitor fuel levels
B. Make sure water is collecting under the oil
C. Check suction and discharge pressures
D. All of the above
25. Which of the following is a typical step in the start-up procedure for a pump?
A. Flush/purge the pump.
B. Ensure the flow rate is as expected.
C. Drain the pump.
D. Close the pump suction.
Process Technology Equipment Chapter 6 Pumps
26. Which of the following is a typical step in the lockout/tagout procedure for a
pump?
A. Warm up equipment.
B. De-energize the driver.
C. Ensure the flow rate is as expected.
D. Shut off the pump.
27. Which of the following is a typical step in the shutdown procedure for a
pump?
A. Drain the pump.
B. Cool down the equipment.
C. Prepare the pump for maintenance.
D. Ensure the flow rate is as expected.
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Clicker Questions
(Note to Instructor: If you have clicker capability in your institution, you may want to
include some of these questions as appropriate. Or perhaps you just want to use them
as a way to check the students’ understanding of the content.)
1. What category of pumps is used more often?
A. Dynamic pumps
B. Centrifugal pumps
C. Rotary pumps
D. Positive displacement pumps
2. What pump should be used in used in high-volume, high-pressure
applications such as boiler-feed water pumps?
A. Single-stage centrifugal pump
B. Multistage centrifugal pump
Process Technology Equipment Chapter 6 Pumps
C. Positive displacement pump
D. Reciprocating pump
3. What pump component is especially critical in preventing environmental
incidents since it may be used to prevent leakage of hazardous materials?
A. Seal flush
B. Bearings
C. Pump seals
D. Mechanical packing
4. What happens to the liquid head in a centrifugal pump as the flow rate is
increased?
A. It increases.
B. It decreases.
C. There is no change.
D. It deadheads.
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APPENDIX, Chapter 6
Table of Contents
Contents
Page
Checking Your Knowledge Answer
Key
32
Process Technology Equipment Chapter 6 Pumps
Checking Your Knowledge Answer Key
1. Define the following terms:
a. Axial pump
b. Centrifugal pump
c. Diaphragm pump
d. Dynamic pump
e. Positive displacement pump
f. Rotary pump
g. Screw pump
h. Vane pump
i. Cavitation
j. Impeller
k. Lobe pump
l. Piston pump
m. Priming
n. Pump performance curve
o. Seal
p. Vanes
q. Viscosity
r. Volute
Process Technology Equipment Chapter 6 Pumps
2. Pump selection is based on (select all that apply):
a. Viscosity
b. Needed discharge pressure
c. Available suction pressure
d. Flow rate
e. Amount of gas in the suction line
6. (True/False) A mechanical packing type sealing system should only be used in
pumps handling hazardous materials.
7. (True/False) Suction head refers to pumping from a point higher than the
liquid (for example, from a sump).
8. Match the potential cause of pump shutdown with the potential
troubleshooting solution:
I. Power failure
a. Check turbine overspeed trip for proper operation; check
suction for proper flow; check discharge lines for large
failure.
II. Flow,
pressure, or
vibration
b. Determine cause (for example, breaker, fuse, or loss of
commercial power). Repair and restore power as
appropriate.
III. Overspeed
trip
c. Pump is using too much horsepower, flow rate is too high,
or mechanical problems exist. Correct problem to return
pump to operation.
IV. Motor trip-out
d. Determine cause (for example, leak, valve closed, or
instrumentation elsewhere in the process). Correct
problem to return pump to operation.
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9. When a pump suffers from ______ lock, the pump loses liquid prime, vibrates,
and makes abnormal noises.
a. vibration
b. vapor
c. cavitation
d. bearing
10. On the diagram below, identify the following parts of a centrifugal pump.
Answers:
1. Casing
2. Discharge Nozzle
3. Eye of impeller
4. Shaft
5. Volute
6. Packing
7. Suction intake
Process Technology Equipment Chapter 6 Pumps
11. Two types of seal systems that employ a seal pot are __________ seal and
________ seal.
12. __________________ in a pumping system is a measure of a pump’s ability to
move liquid through the system.
13. What option would a technician have to increase NPSH available when it is too
low?
a. Decease the pressure above the liquid
b. Decrease the liquid level
c. Increase the pressure above the liquid
d. Increase the liquid temperature
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14. (True/False) During normal pump operations, process technicians must
always wear personal protective equipment (PPE).
15. (True/False) Zero energy state means that all forms of energy have been
removed from the pump.
16. (True/False) When working with pumps, technicians should make sure water is
collecting under the oil.
17. Identify the correct order for the Lockout/Tagout procedure:
____ Shut down any auxiliary systems, such as lube oil and seal flush systems.
____ Close the pump suction and discharge so liquid does not enter the pump.
____ Lock and/or tag the valves and breaker for the motor or valves on the turbine
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____ De-energize the driver by opening the breaker to the motor or blocking the inlet
and exhaust steam valves on the turbine.
____ Flush/purge the pump to clear the pump of the chemical contained in the pump.
____ Drain the pump to the designated collection system.