EFFECTIVELY AVOIDING DOWNTIME THROUGH PERMANENT VIBRATION MONITORING - SOME CASE STUDIES

摘要

A fast remote analysis of occurring vibrations problems permits vibration experts to assist the plant personnel in taking fast actions, avoiding an unavailability of the units, and assuring a more reliable operation. This assistance is certainly valuable when an unstable vibration behaviour occurs, since this can give rise to important changes in vibration amplitudes in a very short time. Some case studies clearly show the added value of a permanent vibration monitoring of turbomachines above the standard vibration protection instrumentation. A first case concerns a partial rub condition on a large 600 MW generator, causing important subharmonic vibrations. A second case describes a rub condition in the hydrogen seal of a generator, causing slow variations in the vibration behaviour during a long period of time.