Identification of Accuracy of Relative Shaft Vibration Value in Large Rotating Machine

The concept of run-out in vibration measurements of large rotating machine is first introduced,then the 4 cases which distortion is generated in vibration measurement value during turbine running are presented.The vibration characteristics analysis demonstrates that the distortion of vibration measurement value attributes to the vibration signal mixed with a false high harmonic signal,the basic method of the identification of the accuracy of the relative shaft vibration value is provided by using spectrum and wave form analysis tools.