Analysis And Diagnostic Method Research On Vibration Characteristics Of Rotor Scaling In Fume Turbine

Fume turbine is an important process equipment as one of the energy recovery unit in FCC workshop,its safe and long term operation not only affects the energy recovery rate but also relates to operation quality of whole reactor and separator.To point at fume turbine high failure rate caused by rotor seriously scaling but defects of present monitoring system and diagnostic method,this paper development a suit of remote monitoring system for fume turbine vibration caused by rotor scaling based on LabVIEW.By means actual test to site fume turbine vibration,one hand checkout the practicability and reliability of the system function.On the other hand according to the vibration condition of actual fume turbine and the rotor scaling situation,establish a causal link between the scaling and vibration.Firstly theoretical analysis the fault mechanism and dynamic model of unbalance and rubbing fault leading by rotor scaling,then carry out the two kind of fault simulation experiment and verify with actual fume turbine vibration.Finally,taking ex ante analysis and ex post analysis to the omen in fault development and symptoms after accident via advanced signal processing method,get some regularity and conclusions with instantly recognizable.Different from the common faults,the unbalanced vibration caused by dynamic blade scaling has unstable phase with the random position and quality of the scale block break off;With the unbalanced fault emerging and developing,the rotor vibration appears that power frequency amplitude step rising and response sensitively to unbalanced excitation,as the same time the displacement time domain waveform is sinusoidal,and the axis orbit is a regular ellipsoid but phase is unstable;after the unbalanced accident,the power frequency amplitude increases continuously and distribute incline as slant in waterfall figure with the revolution rising,the amplitude curve is a uniform parabola,and increasing exponentially.Rotor rubbing caused by enclosure scaling has the feature with stator actively moving to rotor in scaling block growth.During the development of rubbing fault,the frequency-domain waterfall figure shows a large number of high-order harmonics,the displacement time-domain waveform is clipped and distorted,the front orbit get divergence with a number of petals,and finally seriously distorted.The power frequency elliptical orbit whirling ratio increasing continuously and developed into backward whirling,as the same time rubbing friction force will continuously reduce the rotor revolution and the higher speed leading more effect;after rubbing accident,the high order harmonics move to the high frequency direction continuously and the amplitude exceed the power frequency vibration with the revolution rising in waterfall figure.The displacement time domain waveform shows been clipped more seriously and constantly with the uniform distribution,the orbit diverges gradually and crosses frequently,eventually developed into dense reticular distribution.The conclusion from the fault simulation test has certain guiding significance for the fault prediction and accident diagnosis to actual on site fume gas turbine.And the monitoring system designed in this paper can complement and improve the present fume turbine monitoring means with sensitive to vibration caused by scaling,certain practicability and reliability.