In bearing design, what function do the balls or rollers provide?

In bearing design, what function do the balls or rollers provide?

• A. They bear the load
• B. They seal
• C. They lubricate
• D. They guide motion

Answer: (A)

The rolling elements are designed to carry the load between the moving part and the housing. By rolling between the inner and outer races, they transform potentially sliding contact into rolling contact, which greatly reduces friction and wear. This load-bearing role is what lets the shaft rotate smoothly while the bearing supports radial and/or axial forces. Seals and lubrication are separate functions, and while the raceways and rolling elements enable guided, smooth motion, the primary purpose of the balls or rollers is to bear the load.