Abnormal changes in turbine shaft displacement and thrust bearing temperature
Thread Content
The turbines used in our factory are exhaust steam condensing compressors, manufactured by GE. Recently, an anomaly occurred: the shaft displacement suddenly increased from 0.32 to 0.39, before stabilizing at 0.37. The temperature of the shaft bearing on the main thrust side rose by 8 degrees, while the temperature of the shaft bearing on the secondary thrust side increased by 3 degrees. The vibration of the turbine support bearings and the temperatures of the shaft bearings remained stable. Upon checking the trends related to oil pressure, oil temperature, and rotational speed, no fluctuations were detected. Have any of you encountered similar problems?
Both the main steam pressure and temperature are within normal ranges. The key issue in this fluctuation is that the temperatures of both the main thrust and auxiliary thrust bearing shells have increased; however, the increase was smaller for the auxiliary thrust bearing while it was greater for the main thrust bearing
There are many reasons for the increased displacement caused by the steam turbine as well as the rise in bearing temperature; first, check the quality of the steam – it’s possible that the rotor is scaled. Check the changes in exhaust vacuum again, and then consider factors such as increased wear in various steam seal gaps
There isn’t enough information to make a judgment; it is recommended to check the quality of the oil and the quality of the steam first
Could steam carry water? I hope experts can understand; thank you
Here is some additional information: 1. The pressure of the high-pressure steam is 9.0 MPa, and the temperature is 515°C; all parameters are within normal ranges, so it’s unlikely that the steam contains water. 2. The oil quality analysis shows that the levels of mechanical impurities, moisture, flash point, acid value, and viscosity are all within acceptable limits. 3. The exhaust pressure remains at around 20 kPaA, with no fluctuations in the parameters. 4. If the steam seal is worn out, there should be changes in shaft vibration, and steam consumption would increase. Currently, there are no signs of an increase in steam consumption
This is a trend chart; please have the experts give their opinions