Dear all I face to strange behavior vibration of gas turbine.sgt 600 is double shaft gasturbie. Compressor turbine and power turbine. Compressor turbine consist two journal bearing .operational speed is about 10000 rpm for compressor turbine and 7500 rpm for power turbine. Alarm limit is 7 mm/s and the trip limit is 15 mm/s .we have just one accelerometer on the casing near the bearings for measuring and monitoring. overal vibration of both bearing of compressor turbin increase by the same...
Did you restart? How old is it? Have you stable brg. temp and pressure? Any other none normal happenings? Have you inspected mounting of the machine to the foundation? I have another AFAIK unsolved case same machine elsewhere where inspection gave the same result but it create a vibration of the same freq. on all bearings that seem to be unrelated to any speed or other so it would be likely a resonance that is excited from something but your machine seem to have a "better" vibration picture...
Thanks dear oli Temp and pressure are stable.phase vibration is constant .we start more than 5 time at different days. sometime we find the turbine 2 days in service with out increasing vibration. But after shutting down and starting at another day we face to unexpected behavior . Thanks in advance
Yes, the shutdown is normal . At the starting vibration increase at bearing of compressor up to alarm limit but vibration of turbine is good. By passing the critical speeds ,vibration of bearing of compressor decrease but at this time beaing of turbine increase to alarm limit(7mm/s). After that by increasing a little speed of power turbine ,suddenly vibration of bearing of turbine reach to 15mm/s(trip). Age of machine is 3 years .bearing wasn't checked until now . Best regards
So shutdown is normal part from where it trips? Would the vibration be high from start when having a bad start or when do it increase? How old is it? When was bearings checked last time? Can you take a look at the mounting of the machine so nothing misbehave?
Yes we start after event ,vibration some time increase earlier or later . Compressor ideal speed is around 9600 rpm and the pt speed for that is 7300 rpm. By increasing the pt speed to 7500 event will be occur
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .