Examination of the Intermittent High Vibration by the Accumulated Carbide at Oil Deflector of a Steam Turbine for Power Plant

발전용 증기터빈의 Oil Deflector부 탄화물 퇴적에 의한 간헐적 고진동 현상 규명

The intermittent high vibration has been occurred one or two times a day for a 500MW large steam turbine during 5 months. This abnormal vibration was caused by the rubbing between the rotor and the carbide accumulated on the seal tooth of oil deflector. It was found that the accumulated carbide was insulation material installed on the HIP casing from the examination of the chemical composition. Also, this paper presents the mechanism of the intermittent high vibration and the proper method to eliminate this vibration problem. This result would be good practice to find the solution of similar high vibration in the steam turbines for power plant as well as industrial rotating machineries.