Roller bearings have a large rolling surface area in contact with the inner and outer races and typically support heavier loads than comparably-sized ball bearings. A ball bearing’s contact type can be referred to as “point contact”, whereas a roller bearing has a “line contact”. Because of this line contact, the rollers are less likely to become deformed over time. Roller bearings carry heavy loads and can handle shock loads. They are more sensitive to misalignment because there is more surface area to manage the load, and maintaining even contact along the line can be difficult.
Types of Roller Bearings
Cylindrical Roller Bearings
This roller bearing has the highest combined radial load and speed capacity. A non-locating cylindrical bearing has a cylindrical shape that allows the inner ring to have axial movement relative to the outer ring. This is especially important when accommodating thermal expansion. Generally, a roller length that is equal to the roller diameter provides the best balance of load and speed capability.
Needle Roller Bearings
Similar to cylindrical roller bearings but have a much smaller diameter-to-length ratio. They carry high radial loads in a minimal amount of radial space. Sometimes a hardened shaft acts as the needle bearing’s inner race. Cage-separated needle bearings have a retainer and accommodate higher speeds. Full complement style (drawn cup) needle bearings have elements in the outer ring that are up against one another and not separated with a retainer.
Spherical Roller Bearings
Usually contain one or two rows of barrel-shaped rollers within a spherical outer raceway. They support high radial or combined radial and thrust loads in both directions. Spherical bearings have internal, self-aligning capabilities. They can handle misalignment from 0.5 – 2 degrees without affecting rating or life.
Tapered Roller Bearings
Accommodate heavy radial loads, thrust loads, or combined loads. Parts include an inner ring, an outer ring, and tapered rollers that are spaced and contained in a cage. The race and roller angle determine the load capacity. Because they support thrust loads in one direction, they are usually used in sets facing opposite directions.
Cam-Type (Load Following)
These incorporate a shaft and head configuration and accommodate applications with symmetrical and elliptical rotation. Cam-type bearings are used when the shaft needs to follow a specific running alignment or support an extended load.
- Stud / Threaded: has a threaded rod, or stem, that screws into a threaded hole
- Yoke / Shaft Mount: the roller head does not have a stub shaft extension
Key Manufacturers of Roller Bearings We Offer
- Fafnir (Timken)
- FAG (Schaeffler)
- General Bearing
- INA (Schaeffler)
- Kaydon (SKF)
- Rollway (Regal Beloit)
- Schaeffler Group
- Smith Bearing (ABC)
Content on this page was created using excerpts from the Power Transmission Handbook (5th Edition), which is written and sold by the Power Transmission Distributor’s Association (PTDA). The Power Transmission Handbook is just under 400 pages and is a valuable resource for anyone involved or interested in the power transmission industry.