某9FA燃气轮发电机组异常振动分析与处理

Vibration Analysis and Processing Method on a 9FA Gas Turbine Generator

某9FA燃气轮发电机组在大修后启动过程中突发了异常振动,最大振动值达224μm,严重影响机组的安全运行。针对机组起机全过程振动测试结果,分析了振动特性,研究了引发故障的原因。指出该振动是由于轴承标高偏低,承载太轻从而诱发了油膜失稳。在此基础上通过截面弯矩法对机组轴系标高分布进行了测试,并提出了解决方案,有效改善了机组全过程振动情况。

During the starting process of a 9FA gas turbine generator after the first overhaul, large vibration occurred on the 5# bearing, which the maximum value had been reached 224 um. This seriously affect the unit safe running. According to the whole vibration test, vibration characteristic and the cause of bearing fault are analyzed. It is pointed that the vibration was caused by oil whirl, which is aroused as the 5# bearing low elevation and unload position. Also, bending moment method is used to measure the shaft elevation distribution. Corresponding solution is formulated, which can effectively reduce the vibration of the whole process.