可倾轴承损坏引发的燃气轮发电机组 低频振动故障分析

某台大型单轴式燃气轮发电机组发生了不稳定振动。带负荷运行时,#4、#5轴承振动出现随机性大幅波动。对机组带负荷运行状态下的振动进行了测试。试验发现,振动与润滑油温之间有一定关系,振动波动时轴系轨迹紊乱,轴颈中心位置不稳定,振动信号中出现了13 Hz左右的低频分量。振动波动时,50Hz工频分量稳定。轴振波动时瓦振没有波动。对机组上发生的这类少见故障的原因进行了分析。指出可倾轴承损坏是不稳定振动的主要原因。停机后对轴承进行了检修,解决了机组上发生的振动故障。

The Low Frequency Vibration Fault Analysis of Gas Turbine Generator Unit Caused by Tilting Pad Bearing Failure

An unsteady vibration fault occurred on a large single-shaft type gas turbine generator unit. When running at the constant speed 3 000 r/min,vibration of #4 bearing and #5 bearing fluctuated randomly. The vibration of the unit was tested under the normal loading process. There is a certain relationship between the vibration and the oil temperature. The journal orbit is disordered and the journal center position is unstable in case of fluctuation. The low frequency component of the vibration signal is about 13 Hz. The synchronous frequency component of 50 Hz is stable in loading process. When the shaft vibration fluctuated,the bearing vibration did not fluctuate. The cause of this rare fault on the unit was analyzed. The unstable low frequency vibration was caused by the damaged tilting bearing. The bearing was inspected and the vibration fault was solved.