During the commissioning of a 660 MW unit of Dongqi,the vibration of the No.5 bearing exceeded the standard,resulting in a tripping accident of the unit.The accident process was analyzed and summarized,and the on-site vibration monitoring system was used for data analysis.It is judged that the vibration of the unit is abnormal due to dynamic and static friction,and then the unit trips.In the case of low back pressure operation,the radial shaft seal clearance continues to shrink,resulting in dynamic and static friction failures,which cause thermal unbalance in the shaft system of the steam turbine and cause abnormal vibration of the shaft system.Through the re-start of the unit,strict control of the operating parameters,and gradual implementation of dynamic and static part running-in and other means of vibration control,the unit successfully passed the 168 h full-load trial operation,providing a reference for the abnormal vibration of the same type of unit.
关键词
振动异常/跳闸/动静碰磨/热不平衡/轴封间隙
Key words
abnormal vibration/tripping/dynamic and static grinding/thermal imbalance/shaft seal clearance
维普
万方数据