500 MW급 석탄화력발전소 증기터빈축 이상진동 원인분석 및 해결방안 연구

Abstract

본 연구에서는 500 MW급 석탄화력발전소 기동 중 고압 및 중압 증기터빈축 양단 베어링에서 발생한 이상진동 현상의 원인을 규명하고 해결방안을 모색하기 위하여 알려진 이론에 근거하여 분석을 수행하였다. 주파수, 진폭 및위상각 분석결과 접촉에 의해 발생하는 진동의 전형적인 특성이 나타나 이상진동의 원인을 접촉으로 판단하였고 증기터빈을 분해하여 내부부품의 마모를확인하였다. 이상진동을 해소하기 위하여 저속회전 및 발란싱 방법을 적용하였는데 발란싱이 저속회전보다 접촉현상 해소에 우수하였다. 따라서 본 연구와 유사한 특성의 이상진동이 증기터빈에서 발생할 경우 발란싱은 유력한 해결방안이 될 수 있을 것이다.|During the start-up of 500 MW class coal-fired power plant, abnormal shaft vibration occurred on bearings installed both side of high and intermediate pressure steam turbine, so the abnormal vibration phenomenon was analyzed to investigate reason and find a resolution, based on well-known theory in this study. Typical vibration characteristics generated when rotating parts contact stationary parts occurred as a result of analysis for frequency, amplitude and phase angle, so the reason of abnormal vibration was assumed rub and wear of internal part was confirmed during maintenance period of steam turbine. As a result of applying low speed turning and balancing for resolution of abnormal vibration, balancing was more effective than low speed turning for rub removal, so balancing should be excellent resolution in the case of occurrence of abnormal vibration which is similar with this study.; During the start-up of 500 MW class coal-fired power plant, abnormal shaft vibration occurred on bearings installed both side of high and intermediate pressure steam turbine, so the abnormal vibration phenomenon was analyzed to investigate reason and find a resolution, based on well-known theory in this study. Typical vibration characteristics generated when rotating parts contact stationary parts occurred as a result of analysis for frequency, amplitude and phase angle, so the reason of abnormal vibration was assumed rub and wear of internal part was confirmed during maintenance period of steam turbine. As a result of applying low speed turning and balancing for resolution of abnormal vibration, balancing was more effective than low speed turning for rub removal, so balancing should be excellent resolution in the case of occurrence of abnormal vibration which is similar with this study.