汽轮机转子碰磨振动特征实测分析

为了分析识别实际汽轮机组在运行过程中的碰磨故障特征, 采用专用振动监测系统针对多台不同类型和容量的汽轮发电机组的振动信号进行长期连续在线监测, 记录机组长期运行的振动数据, 从中获得大量转子发生径向碰磨故障瞬间产生的冲击振动信号, 并采用信号时域分析和频谱分析技术对典型碰磨信号进行分析处理。比较机组在正常运行状态和碰磨故障状态下振动信号时间波形和频谱可以确定, 在多数情况下, 发生碰磨时机组产生瞬时的冲击振动, 信号中高频结构共振成分明显增加, 但转频及其谐波部分变化不明显。根据这些故障信号特征, 对于碰磨故障振动信号的检测方法和故障分析诊断技术进行讨论。

Analysis of Vibration Signatures of Rubbing in Steam Turbines

Based on the results of a long-time on-line monitoring of vibration of rubbing in steam turbines, the main signatures of rubbing vibration in the time and frequent domains were displayed and analyzed. It has been found that in most cases, signals experience impulsive vibrations for a short-time when rubbing occurs, and the resonance portion in the high-frequent components in the signals increase significantly, but the change of the lower harmonics of the shaft speed is not obvious. According to these signatures, the method of measuring the rubbing vibration signals and the techniques for fault diagnosis were discussed.