某离心压缩机试运转阶段,在工作转速下出现振动爬升,导致轴振过大,引起机组打闸停机。为消除机组故障,对启动过程和工作转速下的轴振进行了测试。根据轴振变化趋势及对不同转速和不同时刻的振动时域和频域特征分析,判明该转子故障是由转子和密封碰磨造成的。为验证故障原因,取出隔板密封和轮盖密封,使转子无法产生密封碰磨,此状态下机组运转良好,说明查找的故障原因正确。调整机组密封间隙后,转子故障消除,机组运转良好。
During the trial operation stage of a centrifugal compressor, the shaft vibration kept increasing when the compressor was operating at the normal working speed, which would cause the power supply shut-down due to the overlarge vibration. In order to eliminate the faults in the compressor unit, the shaft vibrations in starting process and operation at the normal working speed were measured. Through the analysis of the variation trend and the characteristics of the shaft vibration in time domain and frequency spectrum at different rotating speed and different time, it was concluded that the rotor fault was due to the impact-rubbing between the rotor and the seal. In order to verify the fault reason, the diaphragm seal and impeller seal were removed so that the impact-rubbing between the rotor and the seal was avoided. The unit was found to operate well in this state. This test process shows that the fault reason is pertinent. After the seal gap was adjusted,the vibration fault of the unit disappeared.