Many mixer drives include greased bearings that require periodic regreasing.  While it’s generally understood that fresh grease is better than darkened, oxidized grease, it might not be apparent that waiting until you see a visible change in color is often too late.

As grease approaches the end of its useful life, the oil within it oxidizes and begins to dry out.  It separates from the thickeners and forms cakes of material.  While bearing noise and temperature may not have begun to elevate, the old grease must be purged with fresh grease.  If left alone, the old grease can reach a condition where the solid cakes prevent the new grease from replacing it. 

If in doubt about this condition, remove the grease nipple or cap plate to visually inspect the exiting grease and ensure it purges with minimal resistance.  In fact, in extreme cases the old grease cakes can jam the bearing elements and cause sudden failure.

About the author: Mr. Geesaman has been engineering rotating equipment for 8 years and with Philadelphia Mixing Solutions for 4 years. He holds a Bachelors degree in Mechanical Engineering.

Tags: bearings, grease, greased bearings, oxidize, regrease

This entry was posted on Tuesday, October 20th, 2009 at 5:00 pm and is filed under Chemical Processing, Clean Air Processing, Maintenance and Repair, Mineral Processing, Nuclear Waste, Paper and Pulp, Petroleum refining, Research & Development, Wastewater treatment, Water treatment. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.