超临界汽轮机高中压转子弯曲及异常振动的分析与处理

The Analysis and Treatment of HP/IP Rotor's Bending and Abnormal Vibration of the Supercritical Steam Turbine

针对部分660 MW超临界汽轮机在试生产阶段发生的高中压转子永久性弯曲事故,通过研究各机组的异常振动特征及其发展趋势,分析了高中压转子残余内应力的形成机理及其分布规律,确定了转子弯曲的主要原因是:热处理不当导致部分轴段形成残余内应力,并进而引发强烈轴振.为此,对转子再次采取适当的去应力回火技术,并结合机械切削加工和高速动平衡技术,消除了弯曲与振动异常.此外,还提出了一些合理的建议.

Aiming at the accident of permanent bending of some HP/IP rotors of the 660 MW supercritical steam turbine happened during their pre-production stages,the abnormal vibration characteristics and their development trends were studied for each unit,and the mechanism of residual stress formation and its distribution rules in the HP/IP rotors were analyzed.It＇s found out that the primary cause of the rotor＇s bending was abnormal residual stress existing in internal of some shaft sections caused by improper heat treatment,and thus led to strong shaft vibration.By taking proper annealing technique again to remove the residual stress in the rotor,in combination with the techniques of machinery cutting and high-speed dynamic balancing,the rotors＇ permanent bending and abnormal vibration were eliminated finally.Furthermore,some reasonable suggestions were put forward.