Pharmaceutical fan repair
Condition monitoring and balancing
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Working to Achieve
Working to achieve a reliable and predictable plant operation via condition-based monitoring repairs supported by the Machine Sentry® platform.
Our Approach
The fan was added to the Condition Monitoring program. As the fan is behind guarding and there is no access to collect readings with the mobile sensor, Machine Sentry® Fixed (MSF) sensors were fitted. One MSF on the motor DE and one MSF on the motor NDE.
Readings were set to collect once a day. The MSF sensors were installed during the shut-down in 2021. On the monthly visits the readings were then downloaded from the sensor via Bluetooth with a tablet running the Machine Sentry app and then synced to the cloud.
Our Findings
Initial readings showed a high 1x peak, this would indicate an imbalance. An action was raised to clean the impeller and check the fan balance. Over time the trends started to slowly increase, and some rotating looseness started to appear in the bearings.
The additional forces generated from the imbalance had started to cause wear to the bearings. The action was updated to also change out the motor bearings. These works were carried out during the 2022 shut-down.
The Solution
During the shut-down on-site maintenance personnel removed the motor for repair. There was rust and dirt build up noted on the fan impeller and excessive play was seen in the motor bearings. The motor bearings were replaced, and the fan impeller was cleaned of any rust and dirt build up.
When the fan was re installed and a test run preformed high vibration was still observed. AVT Reliability carried out an in-situ fan balance and this rectified the imbalance issues, and the vibration trends returned to acceptable levels as set by ISO.
Follow-Up
The bearings were examined, and a lot of rotating looseness was observed. The looseness is a result of excessive wear on the bearing races from the overload caused by the imbalance in the fan. If the bearings had failed it would have caused secondary damaged to the motor shaft and fan impeller and housing. There would have been a significant financial impact as this failure would have stopped all production on-site.
"This highlights the value in implementing a condition based monitoring program, allowing the site to pro-actively plan repairs and mitigating the potential for an unplanned outage, which would have significantly impacted site production."
