CASE STUDY Vibration Trend Prevents Supply Fan Disruption in Tunnel Dryer
Tunnel dryers in tobacco manufacturing rely on supply fans to maintain steady airflow for consistent drying. At a major facility, a supply fan began showing abnormal vibration patterns. Without prompt action, a chain-related imbalance risked halting operations for more than four days, resulting in significant production and revenue losses.
Waites’ monitoring detected a sharp increase in X-axis peak-to-peak vibration, rising from 2 g to over 20 g. The frequency signature matched the turning speed of the tunnel chain, indicating mechanical imbalance. Inspection revealed the chain had jumped two sprockets, transferring vibration to the fan. This finding directed maintenance to the true source of the problem.
Peak-to-peak vibration on the X-axis spiked to 20.39 g, significantly exceeding the alarm threshold, indicating a severe imbalance related to the tunnel chain speed.
Following the replacement of the damaged fan impeller, vibration velocity quickly returned to normal operating levels, validating the effectiveness of the maintenance intervention.
The chain was reset, lubrication inspected, and associated components verified. Post-repair readings returned to baseline, and new vibration thresholds were established for ongoing monitoring.