We have GE 6FA Gas turbine and Mark-VIe system with TMR configuration. During shutdown of machine load command was changed from 65 MW to 15 MW, and m/c unloaded normally up to 15 MW, but unloading did not stopped at 15 MW. Load further decreased down to 1.89 MW. At same time fuel mode change-over M6BQ to M6Q, as a resultant GCV4 closed. Load started hunting up/down and GCV-1, 2, & 3 also started hunting.
Exhaust thermocouples TTXD1_1, TTXD1_19, TTXD1_20, TTXD1_21 values decreased. It has occurred two times. Please suggest probable reasons.
Is it advisable to check the combustion internals?
Exhaust thermocouples TTXD1_1, TTXD1_19, TTXD1_20, TTXD1_21 values decreased. It has occurred two times. Please suggest probable reasons.
Is it advisable to check the combustion internals?