Eliminating Fan Vibration: A Practical On‑Site Balancing Solution

When a facility notices elevated vibration levels, the most common culprit is fan rotor unbalance. Modern balancing instruments, paired with data‑collection and analysis software, can quickly pinpoint and correct the issue.

Consider the case of a carton‑manufacturing plant that had operated without a predictive maintenance program for years. A new reliability engineer initiated a vibration analysis and identified the root cause: dust and dirt accumulation on the rotor blades had produced a 1× peak in the velocity spectrum. Sine‑wave and phase‑analysis confirmed a static unbalance.

The corrective action was a one‑plane on‑site balancing during the plant’s next shutdown. The balancing instrument performed the runs, and the results were archived in the associated PC software. The latest monitoring technology added a second‑plane control feature, using a second accelerometer to neutralize any negative influence on the non‑drive end (NDE) bearing during trim runs. This ensured that vibrations on both bearings were equally reduced, achieving a target quality grade of 6.3 (DIN ISO 1940).

Within days, the plant returned to full operation and operators reported the fans running smoother than ever. The operations manager noted, “In the past six years, I have never seen those fans run so smoothly.”

Florian Buder, Pruftechnik Canada, Laval, QC.

Find the original article on the MRO Website.