Question No. 1

What maybe the possible causes for the safety trip to trip at normal speed?

Answer:                 

1. Excessive vibration.

2. Leakage in the pilot valve.

3. Deposition of dirt in the safety trip valve.

Question No. 2

What other parts of the steam turbine blades suffer from damage?

Answer:

1. Blade roots.

2. Shroud band.