This was clearly HCF, there were no corrosion issues, but from low load operation, there was a recirculation from the casing sprays that initiated some erosion at the blade root trailing edge. During the remanufacturing the casing sprays were moved back and the angle adjsuted to reduce the...
The entire turbine was trashed, except for the HP case! Fortunately the stator was okay. We rewound the field. This is an interesting case, as the OEM allowed the EPC contractor to commission at low loads with no restrictions. During our subsequent failure meetings, the OEM put new...
you might look at the Turbomachinery magazine. They just came out with their 2006 handbook (Vol. 46 No. 6), which has general spec's for most gas turbines on the market. They have a web site: www.turbomachinerymag.com
This might help.
The total period of time was 21 minutes. The alarm level for the vacuum is 0.2 Bar and the unit was at the trip point of 0.3 bars for a total period of 21 minutes cumulated over 4 separate events (the last event was for 11 minutes which happened 2 weeks prior to the actual failure). Design...
I have a 130 MW STG in a CCGT plant application that experienced high cycle fatigue failure of several of the L-0 buckets in less than 8700 hours of operation. OEM is stating that 4 separate events of low vacuum opertion caused this failure (a total of 21 minutes in duration), The last low...
