300 MW汽轮机低压转子异常振动分析及处理

对机组在大修后开机发生低压转子轴承超温和振动异常的故障原因进行了详细的分析和判断,并通过现场试验,对所出现的低压转子与发电机转子对轮中心刚度不足、机组轴系标高调整不当、轴承支承与接触面不足且润滑状况较差、轴瓦侧隙偏小且不均匀等问题进行及时处理,故障得以妥善解决,机组顺利并网运行。同时指出,通过跨内动平衡加重来降低低压转子外伸端高转速下产生的扰动力,其效果不明显。

Analysis and Treatment for Vibration Fault of Low-pressure Rotor for 300 MW Steam Turbine

The bearing overtemperature and vibration fault of LP rotor during the start of an overhauled unit was analyzed in detail. Based on field testing, such problems as inadequate rigidity of the coupling center between LP rotor and generator rotor, improper adjustment of the unit＇s shafting elevation, insufficient and poorly lubricated bearing support and contact, small and uneven side clearance of bearing bush were disposed timely to enable proper solution of the problem and smooth grid connected operation of the unit. It is also indicated that dynamic balancing weighting in rotor span is not efficient in reducing the perturbed force of the LP rotor＇s protruding end at high rotary speed.