WTO Pumps and Motors 2

Question 1

What is the primary purpose of a pump impeller in a centrifugal pump?

Accepted Answer

To convert mechanical energy into fluid velocity

Answer

The impeller rotates to impart velocity to the fluid, converting mechanical energy from the motor into kinetic energy in the water.

Question 2

A pump is experiencing cavitation. Which operational change would most likely resolve this issue?

Accepted Answer

Reduce the suction lift or increase suction head

Answer

Reducing suction lift or increasing suction head raises the pressure at the pump inlet above the vapor pressure of water, preventing vapor bubble formation.

Question 3

What does NPSH stand for in pump terminology?

Accepted Answer

Net Positive Suction Head

Answer

NPSH (Net Positive Suction Head) is the total head of liquid at the pump suction, used to determine if cavitation will occur.

Question 4

A three-phase motor is running on two phases only due to a blown fuse. What will most likely happen?

Accepted Answer

The motor will overheat and may burn out

Answer

Single-phasing causes unequal current distribution, excessive heat buildup, and can destroy motor windings if not quickly corrected.

Question 5

Which type of pump is best suited for high-flow, low-head water transmission applications at a water treatment plant?

Accepted Answer

Centrifugal pump

Answer

Centrifugal pumps are ideal for high-flow, low-to-moderate head applications and are the most common pump type in water treatment.

(WTO) Water Treatment Operator Certification Practice Test

(WTO) Water Treatment Operator Certification Practice Test

WTO Pumps and Motors 2