Research On The Effect Of Bearing Elevation On Shafting Vibration Of Large Unit

Now the large rotating machinery rotor-bearing system structure becomes more complicated,the probability of faults is also greatly increased.Data show that bearing elevation is one of important factors to cause shafting vibration unit.Bearing elevation will damage the bearing on the state,caused the unreasonable distribution of the bearing load,caused the oil film instability,steam flow induced vibration,rubbing,burning tile and other faults.Therefore,it is of great significance to study the influence of bearing elevation on shafting vibration of large units.The factors that affect the bearing elevation are very complicated.It is difficult to calculate accurately with building models.In this paper,I use the elevation monitoring system based on connectedness and eddy current sensor to change the bearing elevation of the unit during the process of vacuum pumping and load.In order to explore the influence of bearing elevation on the stability of shafting,the lumped parameter method is used to model the shafting structure of a 600 MW supercritical turbo generator set.The transfer matrix method is used to calculate the static elevation and bearing load sensitivity matrix.In addition,using ANSYS to analyze the above unit,calculate the rotor system of natural frequency,vibration mode and critical speed,and discusses the elevation changes on the rotor critical,the influence of rotating speed.Then the experimental bearing elevation on the rotor vibration effect in a three span simulation rotor test-bed.At the end of a 600 MW supercritical steam turbine rotor vibration fault diagnosis,through the collection,analysis of vibration data,determine the flow induced vibration caused by the change of the elevation of steam,adjust the elevation of fault can be solved.