Pro Tip: Variables such as rotation speed, temperature and size should be considered when selecting the best grease for your bearings.

Over-greasing of bearings is said to be the No. 1 factor in premature bearing failure. Excessive lubrication inside the bearing creates heat causing the oil to separate from the thickening agents in the grease. This is known as oil bleed.

Different bearings and even the same bearing on a different application can each have different lubrication needs. Things such as rotation speed, ambient heat and bearing size all factor into selecting the best grease

SKF Manufacturing Company provides the grease volume calculation as G = 0.114 x D x B, where G = the amount of grease in ounces, D = the outside diameter of the bearing in inches and B = the bearing width in inches.

You can purchase grease guns that displace specific volumes per stroke or simply weigh the grease displaced by your plant’s grease guns to learn how many pumps each bearing requires. Most bearing manufacturers can provide you the cycle intervals for when to regrease your bearings.

A new issue is failures related to powered grease guns. Not only can some of these grease guns reach as much as 8,000 to 15,000 psi, they do so without the operator sensing the resistance normally felt when greasing manually.

Grease also needs to be added slowly or you risk damaging the grease ring and especially the seal. In addition to damaging the seal, you’ve also increased the odds of future foreign material exposure from leaking grease or oil.

Based on my experience over the past 40-plus years, I’d recommend a high-quality seal for life bearing that uses an eccentric locking collar. Not only do you save labor and grease, but odds are you get longer bearing life.

Today modern eccentric collars center the shaft in the bearing, which lowers vibration as compared to double setscrew style bearing designs, which push the shaft a few thousandths of an inch out of center and tend to loosen thus requiring additional maintenance.

Installing a modern eccentric locking, sealed-for-lifetime bearing is one of those rare opportunities to get more by doing less and decrease the risk of bearing failure.

Rowdy Brixey is founder and president of Brixey Engineering Inc.


You can connect with him on LinkedIn.