OIT Maintenance and Troubleshooting 3

Question 1

During startup of a heat exchanger, tube-side outlet temperature does not rise as expected. What is the FIRST item to verify?

Accepted Answer

Shell-side heating medium flow is open and flowing

Answer

Without adequate heating medium on the shell side, the heat exchanger cannot transfer heat to the tube-side fluid.

Question 2

A relief valve is found to be leaking slightly at normal operating pressure. What is the MOST likely cause?

Accepted Answer

The set pressure is too close to operating pressure

Answer

Operating too near the set pressure can cause the valve disc to lift slightly, resulting in simmering or leakage.

Question 3

An operator finds that a level transmitter is reading higher than the actual tank level. Which fault is MOST probable?

Accepted Answer

The low-side impulse line is blocked

Answer

A blocked low-side (reference) leg traps liquid and creates a false high-pressure signal, causing the transmitter to read high.

Question 4

What maintenance task should be performed before reinstalling a centrifugal pump after repairs?

Accepted Answer

Check shaft alignment with the driver

Answer

Misalignment is a primary cause of vibration, seal failure, and bearing damage, so alignment must be verified before startup.

Question 5

Which instrument is used to measure shaft misalignment on rotating equipment?

Accepted Answer

Dial indicator

Answer

A dial indicator measures the runout and offset between two rotating shafts to determine alignment quality.

(OIT) Operator in Training Practice Test