200MW汽轮发电机组阵发性振动诊断

Diagnosis of Spasm Vibration of a 200MW Turbogenerator Unit

马头发电厂＃7机在运行中发生了阵发性振动。根据振动频谱特征及大修中发现的问题分析认为:轴系正向推力不足,造成机组＃1～＃3瓦尤其＃2瓦严重下沉,导致高压转子在高负荷区产生蒸汽间隙自激振动,进而引发整个机组的低频振动。提出了消除阵发性振动的措施。

The No.7 turbogenerator operated in Matou Power Plant had occasionally developed a spasmodic vibration when operated above a particular load level. According to the frequency spectral characteristics of vibration, the problem was found in overhaul it is regarded that the subsiding of. Nos. 1-3 bearings especially No. 2 brearing, due to insufficient axial positive pushing force of the unit,has resulted in a self-excited vibration at larger load section of HP rotor, which is caused by steam force generated in the clearance space between stationary and rotating components of the HP cylinder. Thus, the low freqency vibration of other bearings is induced dependently. To dispel this kind of vibration some measures are put foward.