余热电站汽轮发电机组轴振大的处理

巴基斯坦某余热电站汽轮发电机组从额定转速到带负荷运行过程中,3号和4号轴承的轴振存在不同特征。其中3号轴承轴振逐渐增大,数小时后能够在振幅较高范围内趋于稳定运行,而4号轴承的轴振则一直偏大。经过检查轴承结构参数,比较类似机组稳定运行的轴承,分别找出了机组轴振异常的原因。振动故障主要是由质量不平衡、轴承的热稳定性较差造成,进行逐项消除缺陷等改进后,振幅得到减小。

Treatment of Large Vibration for Shaft of Steam Turbine Generator Set in Power Station

On a WHR power plant in Pakistan,when the turbine generator unit ran from rated speed to load carrying,there were different characteristics on the shaft vibration of No.3 and No.4 bearing.The shaft vibration of No.3 bearing was increased gradually but in several hours could run stably with a relative high amplitude while the shaft vibration of No.4 bearing kept rather large all the time.By checking the structural parameters of the bearings and comparing the bearings in similar turbine generator unit which was in normal operation,the reason for abnormal shaft vibration had been respectively found out.The vibration problem was mainly due to mass unbalance and poor thermostability.After remedying the defects one by one,the vibration had been decreased.