What is the best method for lubricating roller bearings?

The best method for lubricating roller bearings is using grease. Grease provides several advantages over oil, especially in applications involving roller bearings. It acts as a better seal against contaminants, helping to keep dirt and moisture out of the bearing, which can significantly extend the lifespan of the bearings.

Grease also has a higher viscosity than oil and adheres better to the bearing surfaces, ensuring that lubrication is maintained even under heavy load and high-speed conditions. This reduces friction effectively and minimizes wear.

In contrast, while oil can also be used for lubrication, it may not stay in place as effectively as grease, particularly in situations where there may be vibration or external force acting on the bearings. Graphite, although a good dry lubricant for certain applications, does not offer the sealing and protective qualities of grease. Water is unsuitable for lubrication as it can cause rusting and corrosion, leading to premature failure of the bearings. Thus, grease is widely accepted as the most effective lubrication method for roller bearings in various operational contexts.