某台超超临界1000MW机组振动故障诊断与治理

某台超超临界1 000MW机组8号轴承轴振动接近停机值,5、6、7号轴承轴振动以及3号轴承座垂直振动均超过报警值,且运行中振动大幅波动。经测试诊断分析,认为引发振动的主要原因为励磁机转子质量不平衡、大负荷工况下低-发联轴器连接状态恶化以及3号轴承座及其基础结构共振。经对励磁机转子采用动平衡,对低-发转子采用热平衡等措施后机组振动降至合格范围。

DIAGNOSIS AND REMEDY OF THE VIBRATION FAULT FOR ULTRA- SUPERCRITICAL 1 000 MW UNIT

The shaft vibration of bearing no.8 for one ultra-supercritical unit has been nearing to shutdown value,the shaft vibration of bearing no 5,6 and 7 as well as the vertical vibration of bearing pedestal no.3,all have been surpassing the alarm values,and large fluctuation of vibration has occurred in operation.Through test,diagnosis,and analysis,it shows that the main causes leading to vibration are non-balancing of the excitor’s rotor mass,and deterioration in connection situation of the coupling between the low-pressure cylinder and the generator under large load condition,as well as resonance vibration between the bearing pedestal no.3 and its foundation structure.For this,through carrying out dynamic balancing of the excitor’s rotor,and additionally installing counter-balance bolt,the vibration of said unit has been lowered into a qualified range.