某330 MW汽轮发电机组异常振动分析与诊断

Analysis and Diagnosis of Abnormal Vibration for a 330 MW Steam Turbine Generator Unit

某发电厂机组调停后开机,带负荷过程中5号轴振爬升导致跳机,诊断为动静碰磨。对轴振变化量进行了分析,判断碰磨位置可能为低发联轴器。根据动静碰磨发生时振动同步分量爬升和非同步分量明显上升现象,进一步阐释了动静碰磨热弯曲和力冲击效应。停机检修时发现低压联轴器有明显的划痕,检查结果表明对此次振动的分析与诊断是正确的,为类似的故障问题提供了诊断思路。

After a scheduled unit shutdown in a power plant, shaft vibration of bearing No.5 increased abnormally during operation and finally led to unit tripping, which turned out to be rubbing between stationary and movable parts. Firstly vibration variation was analyzed and determined that the rubbing occurred probably at the shafting coupling device. As the synchronous component and asynchronous component of vibration increased significantly in the case of rubbing between stationary and movable parts, the paper further expounds thermal bending and force impact effect from the rubbing. During shutdown and maintenance, it is found that there were obvious scratches on the shafting coupling device, which means the vibration analysis and diagnosis is correct, and can provide diagnosis idea for handing similar problems.