汽轮发电机组转子材质缺陷引起的振动问题

用于加工汽轮发电机组转子的毛坯锻件如果存在材质不均或残余内应力过大问题时,会导致加工后的转子在运行中发生振动。讨论了因转子材质缺陷引起的机组振动的机理和振动特点,并结合近年国内出现的与材质缺陷有关的振动诊断和处理实例予以阐述。经分析,转子材质组织不均匀和残余内应力过大将引起机组带负荷工况振动爬升且随运行时间增长振动持续增大,后者将使转子出现一定程度的永久弯曲,并造成一阶临界转速下振动显著增大。

Vibration problems caused by material defects of turbine-generator unit rotor

If the blank forgings used to make turbo-generator unit rotors have the problems of material inhomogeneous or residual internal stress excessive, it will lead to vibration when the processed rotor is running. Combining with the vibration diagnosis and the foundation treatment appeared in domestic which are related with material defects, the mechanism of unit vibration and vibration characteristic caused by rotor material defects were described. By analysis, it was found that rotor material inhomogeneous and residual internal stress excessive will lead to the unit on loading vibration climbing, and which will continuously increase with the increase of running time. The latter will cause some permanent deflections of the rotors and also will lead to vibration increasing obviously while the rotor running under its first order critical rotation speed.