Vibration Based Analysis of Defects in Rotating Shafts

Abstract

The present study aims at the analysis of vibration responses of a horizontal rotor supported on ball bearings and to develop a fault diagnosis system for rotor systems. The sources of vibration in the rotor are the presence of different types of defects, which are cracks in the shaft, bent shaft and misalignment of shafts. These defects are considered with different severity level and their effect on vibration response has been analyzed using response surface methodology. This study gives designers a diagnostic tool for predicting the trends of vibration conditions in a rotor bearing system for healthy and defective shaft conditions. The devised tool has capability of quantifying the amplitude of vibration based on severity of defects in shafts. In such cases, severe vibration has occurred in the system only due to either large slant crack or due to high level of shaft speed. With the features available in the devised diagnostic tool, the proposed model can be used for design, predictive maintenance of a rotor bearing system and also for condition monitoring of high speed rotating machines.