Abstract: The rotating machinery fault on site is complex. Due to the non-stationary signal, the diversity of fault causes, the uncertainty between fault symptoms and faults, the mixing of faults and other reasons, the relationship between faults and symptoms is not completely one-to-one. When conducting equipment vibration analysis and diagnosis, it is necessary to fully grasp various equipment information and flexibly use vibration principles and measurement skills. The organic integration of experience and professional knowledge can effectively carry out fault diagnosis and treatment. Taking a relatively serious failure of a core unit as an example, this paper describes in detail the analysis and handling process of the failure. Based on the application of vibration diagnosis theory, this fault analysis comprehensively uses various types of vibration analysis atlas extracted by the S8000 large rotating machinery vibration monitoring system. Such analysis method can provide reference for the fault diagnosis, analysis and treatment of rotating machinery similar to high-speed flexible turbine rotating machinery.

Key words: steam turbine, condensing turbine with extraction, backpressure turbine with a pass out, revamp, energy conservation