某水电机组导轴承瓦温及间隙异常原因分析

Analysis and Processing of Tile Temperature and Gap Exception for Hydraulic Turbine Guide Bearing

某水电站机组在运行中出现导轴承温度变化异常,导瓦间隙逐渐加大导致机组摆度加大的故障。停机检查发现,下导瓦间隙由0.15 mm增大到0.30 mm以上,上、下导瓦也受到不同程度的磨损,润滑油质劣化。现场测试和分析表明,导瓦表面不平整以及与滑转子的接触面过小,是导致故障的主要原因。通过对机组的轴线、轴瓦的修复和对间隙的重新调整,机组摆度、振动明显改善,导瓦温度基本稳定。

The failure of abnormal temperature variation of the guide bearing was found for a hydraulic power unit in op- eration, the gap of the guide pad was also gradually increased, which resulted the increase of bearing swing. By the field test,it was found that the lower guide bearing tile gap was increased from 0. 15 mm to 0. 30 mm,tbe lubrication oil was deteriorated, and the wear and tear at different degree was found in upper and lower guiding bearing tile. Field test and analysis showed that the main reasons for the failure were the surface of the guide pad is uneven and the contact surface of the sliding rotor is too small.By the reparation of guide bearing tile and unit axis and the adjustment of guide bearing gap ,the swing and vibration of the unit are improved obviously, and the guide bearing tile temperature shows stable basically.