Big Fan of Clean Fans

Drive units have aluminum bases to remove the heat from the high power components (such as the transistor, and diodes). These bases have fins that allow air to flow across them. Some units have fans to pull larger amounts of air across those fins. When the fan gets clogged by contaminants from the machining process (chips, coolant, and grease) the aluminum bases get coated and move less air, which means the life of high power components is shorted. This chain of events will eventually cause an unexpected failure and sudden down machine. This doesn’t have to happen. Periodically pulling the drives out of the machine tool to inspect and perform light cleaning can prevent sudden failure, increase the life of the drive, and save you money.

The photo below shows an example of an axis drive that came in with dirty and clogged fans.

Proper Cleaning If done regularly, cleaning the fans and aluminum bases isn’t hard. Use a mild degreaser to break up the grime then blow off the grime with an air gun – that’s usually enough for light jobs. If the grime has built up, and the fans are completely covered, or no longer turning, it’s best to replace the fans with new ones. While you have the fans removed, soak the aluminum base with a degreaser and scrub with a pipe brush, and blow or wipe down the aluminum base.

For heavier jobs use a wash tank to spray and soak the aluminum base, then blow out the grease and cleaner. Be sure not to get water into the electronics side of the drive. If you do, dry it overnight at 100F in a heat chamber.

Once you’ve completed cleaning the drive, when you put it back into the machine, make sure you apply new gasket material to the base. This seals it to the electrical cabinet, so the cabinet doesn’t get contaminated.

Thanks to Chris Heeg (Board Repair Supervisor, Okuma America) for providing this Service Tip.