Troubleshooting of Start Up for Old Steam Turbine

Abstract

During the start-up of an old steam turbine (about 30 years old), that was internally revamped, it was tripped due to high rotor vibrations. Site investigation was done to find out the root cause. Abnormal casing deformation and rubbing between labyrinth and rotor was found during the investigation. In this study we would like to introduce the detail phenomenon, the root cause analysis, what we learned and what we should have done. We hope this would be beneficial for EPC and the end user to know the impact in case the old steam turbine was partially revamped.