Ball Bearings vs Roller Bearings: What's the Difference?

How each type carries load

A ball makes contact with the raceway at a single point, so a ball bearing has a small contact area. A roller makes contact along a line, spreading the load over a larger area. For the same size, this gives roller bearings a higher load capacity.

Speed

Because of the lower friction at the small contact point, ball bearings are generally better suited to high speeds. Roller bearings run well at moderate speeds under heavy load.

Load direction

Deep groove ball bearings take radial load and some axial load in both directions. Angular contact ball bearings carry combined load, with axial load in one direction per bearing. Cylindrical roller bearings carry radial load only, while tapered and spherical roller bearings carry radial and axial load together.

Misalignment and shock

Self-aligning ball bearings and spherical roller bearings accept some shaft misalignment. Roller bearings cope better with shock and heavy loading than ball bearings of the same size.

Typical uses

• Ball bearings: electric motors, fans, small pumps, conveyors, household and light industrial machines.
• Cylindrical roller bearings: gearboxes, heavy motors, rolling mills, machine tool spindles.
• Tapered roller bearings: wheel hubs, gearboxes, axles.
• Spherical roller bearings: crushers, vibrating screens, heavy fans, mining and cement plant.

Which should you choose?

For light to moderate load and higher speed, start with a ball bearing. For heavy load, shock load or large shafts, start with a roller bearing. If you are replacing an existing bearing, match the old part number rather than switching type.