Deck 16: Pumps

Question 1

Why are centrifugal pumps used more often than positive displacement pumps?

A) They are more effective
B) They are less expensive
C) They require more space
D) They are more complex to operate

Answer 1

B
Explanation: A) Incorrect. Centrifugal pumps tend to be used more often than positive displacement pumps because they are less expensive, require less maintenance, require less space, and are easier to operate.
B) Correct. Centrifugal pumps tend to be used more often than positive displacement pumps because they are less expensive, require less maintenance, require less space, and are easier to operate.
C) Incorrect. Centrifugal pumps tend to be used more often than positive displacement pumps because they are less expensive, require less maintenance, require less space, and are easier to operate.
D) Incorrect. Centrifugal pumps tend to be used more often than positive displacement pumps because they are less expensive, require less maintenance, require less space, and are easier to operate.

Question 2

Which of the following is a main component of a centrifugal pump?

A) Piston
B) Propeller
C) Lobes
D) Volute

Answer 2

D
Explanation: A) Incorrect. The main components of a centrifugal pump are: housing (casing), shaft, inlet (suction eye), outlet (discharge), impeller, bearings and seals, and volute.
B) Incorrect. The main components of a centrifugal pump are: housing (casing), shaft, inlet (suction eye), outlet (discharge), impeller, bearings and seals, and volute.
C) Incorrect. The main components of a centrifugal pump are: housing (casing), shaft, inlet (suction eye), outlet (discharge), impeller, bearings and seals, and volute.
D) Correct. The main components of a centrifugal pump are: housing (casing), shaft, inlet (suction eye), outlet (discharge), impeller, bearings and seals, and volute.

Question 3

What should process technicians do when monitoring and maintaining pumps?

A) Check gas levels to make sure they are satisfactory
B) Check seals and flanges to make sure there are no leaks
C) Feel for leakages
D) Check to make sure water is being used as a lubricant

Answer 3

B
Explanation: A) Incorrect. Process technicians should check oil levels to make sure they are satisfactory.
B) Correct. Process technicians should check seals and flanges to make sure there are no leaks.
C) Incorrect. Process technicians should feel for excessive vibration and heat.
D) Incorrect. Process technicians should make sure water is not collecting under the oil.

Question 4

What should be done to prevent a pump from cavitation?

A) Lubrication
B) Recycle loops
C) Priming
D) Maintenance

Question 5

Which of the following symbols represents a positive displacement pump?

A)
B)
C)
D)

Question 6

What can be used to allow fluid flow circulation if the discharge valves or other downstream valves are closed?

A) Cavitation
B) Recycle loops
C) Priming
D) Vibration

Question 7

Which of the following is an example of a positive displacement pump?

A) Axial
B) Rotary screw pump
C) Multi-stage centrifugal
D) Single-stage centrifugal

Question 8

What type of pump uses a propeller or row of blades to propel liquids axially along the shaft?

A) Axial pump
B) Rotary pump
C) Centrifugal pump
D) Reciprocating pump

Question 9

What is the pressure called that is developed when the speed generated by the centrifugal force is slowed in the volute of the pump casing?

A) Liquid head
B) Deadhead pressure
C) Liquid pressure
D) Centrifugal force

Question 10

What type of pump uses the inward stroke of a piston or diaphragm to draw (intake) liquid into a chamber and then uses an outward stroke to positively displace (discharge) the liquid?

A) Axial pump
B) Rotary pump
C) Centrifugal pump
D) Reciprocating pump

Question 11

Which of the following is a main component of a rotary pump?

A) Shaft
B) Packing/seal
C) Inlet check valve
D) Outlet check valve

Question 12

What can pumps be driven by?

A) Air
B) Electric motors
C) Steam turbines
D) All of the above

Question 13

What type of pump uses an impeller on a rotating shaft to generate centrifugal force, which is converted to pressure in the volute to move liquids?

A) Axial pump
B) Rotary pump
C) Centrifugal pump
D) Reciprocating pump

Question 14

What type of pump uses impellers to generate outward force?

A) Dynamic
B) Plunger
C) Piston
D) Positive displacement

Question 15

Which of the following is a key characteristic of cavitation?

A) Small pressure fluctuations
B) Consistent flow rate
C) Severe vibration
D) Leakage

Question 16

Which of the following symbols represents a centrifugal pump?

A)
B)
C)
D)

Question 17

What type of pump moves liquids by rotating a screw or a set of lobes, gears, or vanes that trap the liquid and physically push it through the pump?

A) Axial pump
B) Rotary pump
C) Centrifugal pump
D) Reciprocating pump