关键词: 非轴伸端, 固有频率, 共振, 动平衡, 轴瓦间隙

Abstract: Asynchronous motors are widely used in the petroleum and petrochemical industry. Taking 3.8MW asynchronous motor as the research object, the vertical vibration problem of the non-driving end of the motor is studied. By analyzing the frequency characteristics to detect the natural frequency of the motor, it is determined that there is a resonance of 50Hz at power frequency in the motor system. We perform dynamic balance test on the motor to confirm the fault characteristic frequency that causes vibration. The cause of the vibration is determined to be weak foundation and bearing bush wear. We adjust the bearing bush clearance after disassembling and checking the motor bearing bush. After the motor runs under load, we measure and analyze the motor operation data. The results show that when the problem of weak motor foundation cannot be solved in the short term, adjusting the bearing bush clearance reasonably has a certain effect on reducing vertical vibration.The vibration control analysis method in the article can provide reference for vibration control of large-capacity motors.

Key words: non-driving end, natural frequency, resonance, dynamic balance, bearing bush clearance