Investigation of process gass compressor shaft vibration phenomena

Case StudyThis paper presents details of investigation results of issues observed during plant start-up on a centrifugal compressor. Compressor was operated with air/ nitrogen during start-up and high shaft vibration (approx. 75 um) were observed on DE side of compressor accompanied by high levels of coast down vibration levels (exceeding alarm levels). This paper presents subsequent detailed rotor dynamics analysis to understand root cause of the high vibrations