Are the two basic categories of rolling-element bearings ball bearings and roller bearings?

The statement is true because rolling-element bearings are generally classified into two primary categories: ball bearings and roller bearings.

Ball bearings utilize spheres as their rolling elements, which facilitate movement with minimal friction. They are particularly effective at handling radial loads and moderate axial loads. Their design allows for smooth operation and high-speed applications.

Roller bearings, on the other hand, employ cylindrical or tapered rollers as rolling elements, which provide a larger contact area with the races compared to balls. This characteristic allows roller bearings to support heavier loads and endure higher pressures, making them suitable for various mechanical applications.

The distinction between these two categories is fundamental in the field of equipment maintenance as it influences decisions related to selecting the appropriate bearing type for specific applications, considering factors such as load capacity, speed, and overall performance.