Question 1

Why are centrifugal pumps used more often than positive displacement pumps?&#10;A) They are more effective&#10;B) They are less expensive&#10;C) They require more space&#10;D) They are more complex to operate

Accepted Answer

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?&#10;A) Piston&#10;B) Propeller&#10;C) Lobes&#10;D) Volute

Accepted Answer

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?&#10;A) Check gas levels to make sure they are satisfactory&#10;B) Check seals and flanges to make sure there are no leaks&#10;C) Feel for leakages&#10;D) Check to make sure water is being used as a lubricant

Accepted Answer

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?&#10;A) Lubrication&#10;B) Recycle loops&#10;C) Priming&#10;D) Maintenance

Accepted Answer

A) Incorrect. Priming a pump involves filling the suction line and casing of a pump with liquid to remove vapors and to heat or chill the case metal to its service temperature.
B) Incorrect. Priming a pump involves filling the suction line and casing of a pump with liquid to remove vapors and to heat or chill the case metal to its service temperature.
C) Correct. Priming a pump involves filling the suction line and casing of a pump with liquid to remove vapors and to heat or chill the case metal to its service temperature.
D) Incorrect. Priming a pump involves filling the suction line and casing of a pump with liquid to remove vapors and to heat or chill the case metal to its service temperature.

Question 5

Which of the following symbols represents a positive displacement pump?&#10;A)  &#10;B)  &#10;C)  &#10;D)

Accepted Answer

A) Incorrect. This is the symbol for a centrifugal pump.
B) Correct. This is the symbol for a positive displacement pump.
C) Incorrect. This is the symbol for a centrifugal pump.
D) Incorrect. This is the symbol for a centrifugal pump.

Question 6

What can be used to allow fluid flow circulation if the discharge valves or other downstream valves are closed?&#10;A) Cavitation&#10;B) Recycle loops&#10;C) Priming&#10;D) Vibration

Accepted Answer

A) Incorrect. Cavitation is a condition inside a pump in which the liquid being pumped partly vaporizes because of variables such as increased temperature and pressure drop.
B) Correct. Recycle loops allow fluid flow circulation if the discharge valves or other downstream valves are closed.
C) Incorrect. Priming a pump involves filling the suction line and casing of a pump with liquid to remove vapors and to heat or chill the case metal to its service temperature.
D) Incorrect. Recycle loops allow fluid flow circulation if the discharge valves or other downstream valves are closed.

Question 7

Which of the following is an example of a positive displacement pump?&#10;A) Axial&#10;B) Rotary screw pump&#10;C) Multi-stage centrifugal&#10;D) Single-stage centrifugal

Accepted Answer

A) Incorrect. An axial pump is an example of a dynamic pump.
B) Correct. A rotary screw pump is an example of a positive displacement pump.
C) Incorrect. A multi-stage centrifugal pump is an example of a dynamic pump.
D) Incorrect. A single-stage centrifugal pump is an example of a dynamic pump.

Question 8

What type of pump uses a propeller or row of blades to propel liquids axially along the shaft?&#10;A) Axial pump&#10;B) Rotary pump&#10;C) Centrifugal pump&#10;D) Reciprocating pump

Accepted Answer

A) Correct. An axial pump uses a propeller or row of blades to propel liquids axially along the shaft (as opposed to centrifugal pumps that use an impeller to force liquids to the outer wall of the chamber).
B) Incorrect. A rotary 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.
C) Incorrect. A centrifugal pump uses an impeller on a rotating shaft to generate centrifugal force, which is converted to pressure in the volute to move liquids.
D) Incorrect. A reciprocating 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.

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?&#10;A) Liquid head&#10;B) Deadhead pressure&#10;C) Liquid pressure&#10;D) Centrifugal force

Accepted Answer

A) Correct. Liquid head that is developed when the speed generated by the centrifugal force is slowed in the volute of the pump casing.
B) Incorrect. The maximum liquid head occurs at zero flow, with the discharge valve shut; this is called the deadhead pressure.
C) Incorrect. Liquid head that is developed when the speed generated by the centrifugal force is slowed in the volute of the pump casing.
D) Incorrect. Centrifugal force is an apparent force exerted on the fluid by the impeller rotating in a circular pattern to move it outward from the center.

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?&#10;A) Axial pump&#10;B) Rotary pump&#10;C) Centrifugal pump&#10;D) Reciprocating pump

Accepted Answer

A) Incorrect. An axial pump uses a propeller or row of blades to propel liquids axially along the shaft (as opposed to centrifugal pumps that use an impeller to force liquids to the outer wall of the chamber).
B) Incorrect. A rotary 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.
C) Incorrect. A centrifugal pump uses an impeller on a rotating shaft to generate centrifugal force, which is converted to pressure in the volute to move liquids.
D) Correct. A reciprocating 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.

Question 11

Which of the following is a main component of a rotary pump?&#10;A) Shaft&#10;B) Packing/seal&#10;C) Inlet check valve&#10;D) Outlet check valve

Accepted Answer

The answer of Which of the following is a main...

Question 12

What can pumps be driven by?&#10;A) Air&#10;B) Electric motors&#10;C) Steam turbines&#10;D) All of the above

Accepted Answer

The answer of What can pumps be driven by?&#10;A) Air&#10;B)...

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?&#10;A) Axial pump&#10;B) Rotary pump&#10;C) Centrifugal pump&#10;D) Reciprocating pump

Accepted Answer

The answer of What type of pump uses an impeller...

Question 14

What type of pump uses impellers to generate outward force?&#10;A) Dynamic&#10;B) Plunger&#10;C) Piston&#10;D) Positive displacement

Accepted Answer

The answer of What type of pump uses impellers to...

Question 15

Which of the following is a key characteristic of cavitation?&#10;A) Small pressure fluctuations&#10;B) Consistent flow rate&#10;C) Severe vibration&#10;D) Leakage

Accepted Answer

The answer of Which of the following is a key...

Question 16

Which of the following symbols represents a centrifugal pump?&#10;A)  &#10;B)  &#10;C)  &#10;D)

Accepted Answer

The answer of Which of the following symbols represents a...

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?&#10;A) Axial pump&#10;B) Rotary pump&#10;C) Centrifugal pump&#10;D) Reciprocating pump

Accepted Answer

The answer of What type of pump moves liquids by...

Deck 16: Pumps