We have made considerable improvement in the reliability of our fin-fan fans. Our program includes changes to design, repair practices and preventive maintenance.
Many of our fans were originally built with V-belt drives. Almost all of them have been converted to cog belts. We standardized on heavy duty, flange-mount roller bearings. We have made improvements to the structure that supports the motor in many fans where the original support was inadequate to maintain proper belt alignment and tension.
We created a repair sheet for our mechanics to use when repairing fans. In makes sure that they check all of the critical parameters and continually updates and corrects our documentation. We have purchased the tools necessary to do high quality alignment and tension adjustments. We use a laser system for belt alignment. We use a simple spring mechanism to check and adjust tension.
We standardized on a single grease for use in all fans. We set up a preventive maintenance program to grease most fan bearings quarterly. In order to be able to safely access the upper bearing for this task, we extended the grease fittings down below the guard using stainless steel tubing.
We do not perform routine vibration monitoring of our fans. But, if the operators notice a problem, they call for a vibration technician to take data and analyze for possible problems with balance, alignment or bearing condition. We have performed field balance if the vibration indicates it is needed.
Johnny Pellin
