SERVICE
What are the causes of excessive vibration and loud, harsh noise during motor operation, and how can these issues be addressed?
There may be several possible causes of the malfunction, such as,
Misalignment: The coupling connecting the motor to the pump, fan, or other load is off-center; in belt drives, the belt tension is uneven.
Mechanical faults: bearing wear, oil starvation, bearing spalling; rotor shaft bending, rotor imbalance;
Anchor bolts are loose, and the base foundation is unstable.
Electromagnetic noise: three-phase voltage imbalance, loose iron core, and broken rotor cage bars.
Stator rubbing (bearing failure causing the rotor to rub against the stator core).
The handling method is as follows:
Identifying abnormal noises: a steady hum indicates an electromagnetic issue; metallic friction suggests bearing wear or stator‑rotor rubbing—replace the bearings promptly.
Re‑align the coupling to ensure coaxiality and adjust the belt tension.
Tighten all anchor bolts and reinforce the vibration-isolating base.
Balance the three-phase voltage and inspect for broken rotor bars.
Bearing clearance inspection requires shutdown for maintenance, including core repair and bearing replacement.
