Indian Journal of Science and Technology

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Vibration Analysis of Misaligned Shaft-ball Bearing System


Affiliations
1 Dept. of Mech. Engg., Kongu Engg. College, Perundurai, Erode- 638052, India
2 Knowledge Institute of Technology ,Salem, 637504, India
 

Experimental studies were performed on a rotor dynamic test apparatus to predict the vibration spectrum for shaft misalignment. A self-designed simplified 3 pin type flexible coupling was used in the experiments. The rotor shaft accelerations were measured using dual channel vibration analyzer (ADASH) under the misalignment condition. The experimental and numerical (ANSYS) frequency spectra were obtained. The experimental predictions are in agreement with the ANSYS results. Both the measured and ANSYS results spectra shows that misalignment can be characterized primarily by 2X (two times) shaft running speed. However, misalignment 2X is not close enough to one of the system natural frequencies to excite the system appreciably. Therefore, there are cases where the misalignment response is hidden and does not show up in the vibration spectrum. On the other hand, if 2x shaft running speed is at or close to one of the system natural frequencies, the misalignment effect can be amplified and the speed is pronounced in the frequency spectrum.

Keywords

Misalignment, Vibration Analysis, Pin Type Flexible Coupling, Ball Bearing
User

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  • Vibration Analysis of Misaligned Shaft-ball Bearing System

Abstract Views: 573  |  PDF Views: 346

Authors

V. Hariharan
Dept. of Mech. Engg., Kongu Engg. College, Perundurai, Erode- 638052, India
P. S. S. Srinivasan
Knowledge Institute of Technology ,Salem, 637504, India

Abstract


Experimental studies were performed on a rotor dynamic test apparatus to predict the vibration spectrum for shaft misalignment. A self-designed simplified 3 pin type flexible coupling was used in the experiments. The rotor shaft accelerations were measured using dual channel vibration analyzer (ADASH) under the misalignment condition. The experimental and numerical (ANSYS) frequency spectra were obtained. The experimental predictions are in agreement with the ANSYS results. Both the measured and ANSYS results spectra shows that misalignment can be characterized primarily by 2X (two times) shaft running speed. However, misalignment 2X is not close enough to one of the system natural frequencies to excite the system appreciably. Therefore, there are cases where the misalignment response is hidden and does not show up in the vibration spectrum. On the other hand, if 2x shaft running speed is at or close to one of the system natural frequencies, the misalignment effect can be amplified and the speed is pronounced in the frequency spectrum.

Keywords


Misalignment, Vibration Analysis, Pin Type Flexible Coupling, Ball Bearing

References





DOI: https://doi.org/10.17485/ijst%2F2009%2Fv2i9%2F29521