Analysis of the Influence of the Mechanical Imbalance and the Bearing Clearance on the Operating Stability of Hydro-power Unit

doi:10.3901/JME.2016.03.049

Abstract

Abstract: The operating instability of the hydro-power units is often caused by the mechanical imbalance and the excessive bearing clearances. In order to identify the reasons for the vibration of a 45 MW Kaplan turbine, the stability test is done to obtain the vibration and swing information. Through the spectrum and shaft orbit analysis, the reason for the vibration is found out to be the mechanical imbalance and the excessive bearing clearances. The clearances are adjusted and the balancing test is taken using the key phase point method to reduce the amplitude of the vibration and swing. After the clearance is adjusted and 36 kg balance weight is added to the rotor, the amplitude of the vibration and the swing are all reduced into the allowable range. Which means the joint analysis method is appropriate for the vibration problems caused by multiple factors. The spectrum and shaft orbit joint analysis can reduce the number of tests and improve the accuracy of fault diagnosis. And the step by step test and analyze method which can quickly identify the main reason among a lot of reasons is clearly introduced.

Key words: bearing clearances, key phase point method, mechanical imbalance, operating stability test

CLC Number:

TV734

MENG Long, LIU Meng, ZHI Falin, ZHOU Lingjiu, WANG Zhengwei. Analysis of the Influence of the Mechanical Imbalance and the Bearing Clearance on the Operating Stability of Hydro-power Unit[J]. Journal of Mechanical Engineering, 2016, 52(3): 49-55.

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