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.