OIT OIT Pumping Systems and Hydraulics 2

Question 1

What is water hammer and what causes it?

Accepted Answer

Pressure surge caused by rapid change in fluid velocity, such as sudden valve closure

Answer

Water hammer is a pressure surge or wave caused by a sudden change in fluid velocity, commonly triggered by rapid valve closure or pump shutdown.

Question 2

What is the function of a pressure relief valve in a pumping system?

Accepted Answer

To automatically release excess pressure and protect system components from overpressure

Answer

A pressure relief valve automatically opens to discharge fluid when system pressure exceeds a set limit, protecting pipes and equipment from damage.

Question 3

What does pump efficiency measure?

Accepted Answer

The ratio of hydraulic power output to shaft power input

Answer

Pump efficiency is the ratio of the hydraulic power imparted to the fluid to the mechanical shaft power supplied to the pump.

Question 4

If a pump is operating to the right of its best efficiency point (BEP) on its curve, what is likely happening?

Accepted Answer

The pump is moving more flow than its design point, potentially causing cavitation and overheating

Answer

Operating to the right of BEP means the pump is moving excess flow, which can lead to cavitation, motor overloading, and reduced pump life.

Question 5

What is the purpose of a variable frequency drive (VFD) on a pump motor?

Accepted Answer

To adjust pump speed to match varying system demand and save energy

Answer

A VFD varies the motor speed (and thus pump output) to match system demand, saving significant energy compared to running pumps at full speed constantly.

(OIT) Operator in Training Practice Test

(OIT) Operator in Training Practice Test

OIT OIT Pumping Systems and Hydraulics 2