CASE STUDY Early Detection of Unbalance Prevents Arbor Bearing Failure at Lumber Mill
The arbor bearing in a planer top head is critical to smooth lumber processing. Failure can disrupt operations and cause expensive repairs. At a lumber mill, Waites’ sensors detected abnormal vibration on the arbor bearing non-drive end.
Velocity FFT spectrum showed a 1x peak at 59.7 Hz with increasing RMS and pk-pk vibration, clear signs of unbalance. Although the site’s first inspection found nothing abnormal, Waites’ analysts kept the team informed that vibration required further investigation. Persistent monitoring confirmed an unbalance condition that required corrective action.
Velocity trend on the arbor bearing showed rising vibration levels through June, confirming analyst concerns and prompting further investigation despite initial inspections finding no issues.
FFT spectrum after corrective action showed the 1x peak at 59.7 Hz returning to normal amplitude, confirming that vibration levels had stabilized.
The maintenance team replaced the motor and gearbox after identifying a rolled key that caused coupler failure. Waites’ analysts confirmed stable vibration levels and reset baselines.