Investigation on Axial Displacement Fault Mechanism Based on Dynamic Characteristic Coefficients Identification of Tilting-Pad Thrust Bearing
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To prevent the thrust bearing damage faults, the thrust bearing pad temperature and the static axial displacement variation are usually monitored and cared about, but axial vibration caused by axial dynamic excitation can also result in the severe rubbing. An electric oil pump system with overflow valve is designed on a similar industrial centrifugal compressor test-rig to apply the axial low-frequency excitation from 3 to 7 Hz, and the axial and radial vibration response amplitudes are analyzed. Then, the stiffness and damping coefficients of tilting-pad thrust bearing (TPTB) are identified by instrumental variable filter (IVF) algorithm to reveal the mechanism of TPTB dynamic characteristics affecting axial vibration. Finally, a fault case about surge and the rubbing of thrust bearing is studied. Compared with axial vibration, radial vibration does not directly correlate to axial excitation, and the axial frequency spectrum is an effective method to diagnose axial displacement faults; the static axial load, the dynamic excitation amplitude and the excitation frequency all exert influence on thrust bearing dynamic characteristics and axial vibration response. The research results can guide the design of thrust bearings and help to diagnose the axial displacement faults, while the test device and method can be used to measure the static and dynamic characteristics of thrust bearings.
KeywordsAxial displacement fault IVF algorithm Thrust bearing Dynamic characteristics
This research has been supported by the National Natural Science Foundation of China (51775030) and the Fundamental Research Funds for the Central Universities (BHYC1703A).
- 4.L. San Andrés, B. Koo, M. Hemmi, A flow starvation model for tilting pad journal bearings and evaluation of frequency response functions: a contribution towards understanding the onset of low frequency shaft motions, Proceedings of ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. Charlotte, NC, USA (2017)Google Scholar
- 8.B.R. Nichols, R.L. Fittro, C.P. Goyne, Subsynchronous vibration patterns under reduced oil supply, Proceedings of ASME Turbo Expo 2017: Turbomachinery Technical Conference and Exposition. Charlotte, NC, USA (2017)Google Scholar
- 18.M. Wodtke, M. Fillon, A. Schubert et al., Study of the influence of heat convection coefficient on predicted performance of a large tilting-pad thrust bearing. J. Tribol. 135(2), 021702-1-11 (2013)Google Scholar
- 19.L. Zhai, Y. Luo, Z. Wang et al., A review on the large tilting pad thrust bearings in the hydropower units. Renew. Sustain. Energy Rev. 69, 1182–1198 (2016)Google Scholar
- 21.W. Wang, J. Gao, Y. Li, et al, Study of fault self-recovery and seal improvement for centrifugal compressor. ASME Turbo Expo 2010: Power for Land, Sea, and Air. Glasgow, Scotland (2010)Google Scholar
- 23.U. Haupt, K. Bammert, M. Rautenberg, Blade vibration on centrifugal compressors—blade response to different excitation conditions. Int. J. Turbo Jet Engines 4(3–4), 271–284 (1987)Google Scholar
- 24.W. Wang, Q. Li, L. Chen, et al, Effect of specific load of bearing on the centrifugal compressor rotordynamic stability, Proceedings of ASME Turbo Expo 2015: Turbomachinery Technical Conference and Exposition. Montreal, Quebec, Canada (2015)Google Scholar