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Dear all,
After a recent GT MI on our frame V MS5001 NP gas turbine, a lube oil leaking issue has developed near the 2nd bearing inside the heat shield.
Initially, it was discovered since there are thick oil mist coating on the UV detectors. By tracing the oil mist stain left in the enclosure, we locked the source of leaking at the 2nd bearing behind the heat shield.
After some investigation, we found that during the major inspection, no Loctite was applied on the oil baffle and all the bearing guard/covers (I am not a mechanical guy). As a result, we opened the bearing No. 2 top cover without opening the exhaust plenum. we cleaned the surface, applied Loctite 510 and did re-tourquing on all of the bolts. However, we did not touch the oil baffle (which was not changed during the GT MI).
2 weeks later, the metal rim above the heat shield developed some visible black burn marks. After checking the bearing cover behind the heat shield, small pool fire was observed. The flame is continuous and had to be put out twice after the GT shutdown.
Our plan now is to open up the roof/exhaust plenum top cover, the 2nd bearing assembly to estimate the damage caused. At the same time, we are planning to change the 2nd bearing oil baffle as well. However, we are not sure about the exact cause of the leakage/fire.
I would like to seek your expertise in determining the cause of the leakage. At the same time, are there any other parts which we have overlooked? What's the worst possible damage can be caused by the fire (at least 2 weeks, since the flame is small and hidden behind the heat shield, it was not captured by the UV detectors). Really appreciate your input, if additional information is required, I will be more than happy to provide the details. Thank you again for reading this thread.
Best Regards,
Dawei
After a recent GT MI on our frame V MS5001 NP gas turbine, a lube oil leaking issue has developed near the 2nd bearing inside the heat shield.
Initially, it was discovered since there are thick oil mist coating on the UV detectors. By tracing the oil mist stain left in the enclosure, we locked the source of leaking at the 2nd bearing behind the heat shield.
After some investigation, we found that during the major inspection, no Loctite was applied on the oil baffle and all the bearing guard/covers (I am not a mechanical guy). As a result, we opened the bearing No. 2 top cover without opening the exhaust plenum. we cleaned the surface, applied Loctite 510 and did re-tourquing on all of the bolts. However, we did not touch the oil baffle (which was not changed during the GT MI).
2 weeks later, the metal rim above the heat shield developed some visible black burn marks. After checking the bearing cover behind the heat shield, small pool fire was observed. The flame is continuous and had to be put out twice after the GT shutdown.
Our plan now is to open up the roof/exhaust plenum top cover, the 2nd bearing assembly to estimate the damage caused. At the same time, we are planning to change the 2nd bearing oil baffle as well. However, we are not sure about the exact cause of the leakage/fire.
I would like to seek your expertise in determining the cause of the leakage. At the same time, are there any other parts which we have overlooked? What's the worst possible damage can be caused by the fire (at least 2 weeks, since the flame is small and hidden behind the heat shield, it was not captured by the UV detectors). Really appreciate your input, if additional information is required, I will be more than happy to provide the details. Thank you again for reading this thread.
Best Regards,
Dawei