Expert Guide to Bearing Lubrication: Selection, Use, and Storage

Why Lubrication Matters

In every bearing, proper lubrication is essential to keep the rolling elements and races, or the shaft and plain bearing, from direct contact. A high‑quality lubricant—containing the right additives and viscosity—creates a protective film that reduces friction, heat, and wear.

Choosing the Right Lubricant

For oil‑lubricated bearings, viscosity is the key factor. The required viscosity depends on operating temperature and speed. An oil that is too thin will fail to form a sufficient film, allowing metal‑to‑metal contact that generates heat and accelerates wear. Conversely, an overly thick lubricant can create excess drag and heat buildup.

Grease is the most common alternative for many applications, especially where a stable, long‑lasting film is needed. Your SKF dealer can supply detailed data sheets and recommendations tailored to your specific load and speed conditions.

Using the Correct Quantity

Once the lubricant type is selected, the amount applied is equally critical. Too little lubricant leads to inadequate film thickness and premature failure; too much can cause heat generation, oil migration into motor housings, and even electrical shorts in electric motor bearings. Studies show that over‑lubrication often results in more bearing damage than under‑lubrication. SKF’s product literature includes precise fill‑rate guidelines for your application.

Storage and Contamination Prevention

Proper storage of lubricants is vital. Exposure to moisture or aggressive chemicals can degrade the oil or grease, leading to water‑induced corrosion. When a bearing is idle, free water tends to settle at the bottom of the housing, concentrating near the load zone and creating “etching” – a deep‑seated corrosion that undermines the bearing’s structural integrity. This is especially problematic in high‑temperature, chemically aggressive environments such as paper‑machine dryer sections.

To mitigate these risks, seal the bearing housing to prevent moisture ingress, use lubricants with proven rust‑inhibiting additives, and regularly inspect for contamination.

Figure 2 – Etching and its impact on bearing life.

For the most accurate lubricant selection and application guidance, consult the original SKF article here.

At J/E, we are proud to be an authorized SKF distributor. We stock a full range of bearings, seals, and lubricants. For product inquiries, visit our contact page or email info@je-bearing.com.