Using Operating Deflection Shapes to Detect Misalignment in Rotating Equipment

In this paper, we demonstrate the effects of rotating machin-ery shaft misalignment on its dynamic behavior which is characterized in the form of an Operational Deflection Shape (ODS). In this approach, an ODS derived from mul-tiple accelerometer signals acquired at various points on the machine is used to diagnose shaft misalignment. Tests are performed on a machinery fault simulator under various operating conditions. Operating data is simultane-ously acquired using a multi-channel data acquisition sys-tem. Since misalignment produces dominant motion at the rotor running speed and its harmonics, this data is used to construct an ODS. The emphasis is on correlating the ODS of the machine when properly aligned with its ODS following induced shaft misalignment. The results of this work will provide a new perspective of machinery fault detection. The aim is to de-velop a more reliable tool for determining shaft misalign-ment and other machine faults from operating data