CASE STUDY Critical Fan Wheel Imbalance Caught Before $406K Failure
At an energy facility, Waites analysts detected an increasing velocity vibration trend on an induced draft fan. The issue was first called out in December and continued to be monitored as vibration levels remained elevated across both the shaft drive end and non-drive end.
As the condition progressed, vibration data showed a strong peak at running speed, indicating a developing imbalance condition with possible looseness. When levels spiked significantly in April, Waites escalated the Action Item to critical and recommended immediate inspection.
The facility shut down the equipment and performed an inspection. When the fan stopped, the fan wheel fell off the hub mount. The customer confirmed that corrosion in the mounting hardware appeared to be the cause.
The failed hub connection created a major imbalance condition and elevated vibration across the asset. Based on the inspection findings, the facility replaced the fan wheel, shaft, and shaft bearings.
Velocity levels increased over time before spiking sharply, prompting Waites analysts to escalate the Action Item to critical.
After Waites escalated the Action Item, the facility actively shut the fan down for inspection and repair. The confirmed issue showed that the fan wheel had separated from the hub mount, creating a major imbalance condition that could have caused severe secondary damage if left unresolved. Maintenance teams replaced the fan wheel, shaft, and shaft bearings, then balanced the asset upon startup.
Following the repair, Waites analysts confirmed that overall vibration levels decreased significantly, validating both the diagnosis and corrective action. The early warning helped the facility avoid a much larger failure event and complete the repair under controlled conditions.