Analysis on the Dynamic Vibration Absorption of Bearings of the Large Turbo Unit

doi:10.11930/j.issn.1004-9649.201703019

Abstract

Abstract: Aiming at the abnormal structural vibration occurred on the bearings of large turbo units, the dynamic model of the rotor-bearing-support system with flexible support is set up to analyze the abnormal structural vibration phenomenon using the dynamic vibration absorber theory. The result shows that the support stiffness of the bearings located on the exhaust cylinder is low. The natural frequencies of the bearings and the rotor system may be reduced from more than 50 Hz as being designed to less than 50 Hz. Once the natural frequencies of the bearings and the rotor system are superposed, the vibration absorbing phenomenon tends to occur. The shaft vibration transfers to the bearings, resulting in small shaft vibration and large bearing vibration. At this time, the system natural frequency is decomposed into two, which are distributed on both sides of the natural frequency. Consequently, a double resonance peak appears.

Key words: turbo unit, dynamic vibration absorber, bearing vibration, shaft vibration

CLC Number:

TK268.+1

WU Yajun, YANG Tianhai, JIANG Chaohui, YANG Jiangang, CAO Zhongxun. Analysis on the Dynamic Vibration Absorption of Bearings of the Large Turbo Unit[J]. Electric Power, 2017, 50(10): 116-119.

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URL: https://www.electricpower.com.cn/EN/10.11930/j.issn.1004-9649.201703019

https://www.electricpower.com.cn/EN/Y2017/V50/I10/116

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