It’s not hard to understand why some product designers and engineers would hesitate to use plastic bearings in their designs.
After all, they’re probably used to rugged products and subsystem components like bearings being made from alloys such as steel and bronze. Or they simply don’t think plastics can handle tough applications or extreme environmental conditions.
Why would you use plastic bearings and bushings? Depending on the application, choosing to use plastic over metal materials can offer exceptional advantages. Plastic bearings contribute to longer life, reduced maintenance costs, and lower energy consumption.
Plastic ball bearings are bearings built from plastics, such as nylon, acetal, and PTFE. They can be self-lubricating when combined with carbon graphite and other non-metallic materials.
These types of bearings were a necessary development to replace metallic bearings in applications with a higher risk of corrosion, electrical conduction, and magnetism.
For instance, they were not ideal for food processing, swimming pools, and applications in the medical field. Also, they can be easily machined to fit various applications and absorb shocks better than metal, since plastics are naturally elastic.
This type of bearing (no matter the material) has a wide range of applications. This is because they are built to withstand heavy loads and high operating speeds.
In applications where the load is both axial (acting along the shaft) and radial (acting around the side of the shaft), deep groove ball bearings have proven to be dependable. Although the amount of axial load capacity is limited. But when built of plastic, this gives a silent and smooth bearing.
This is a type of rotary bearing built specifically for axial load, not radial loads. They are available as single direction or double direction thrust ball bearings and are designed to support thrust loads at high speeds. The plastic variant of thrust ball bearings makes them the best option for high-precision use.
Angular contact bearings have their bearing axis at an angle with the line of action of the load. And this load could be radial or thrust loads. But the thrust can only be in one direction. They’re ideal for high-speed applications.
How can a plastic ball bearing be self-aligning? When its outer ring’s trajectory is spherical. The center of curvature of the bearing matches the center of the bearing. This allows the inner ring, ball, and retainer to rotate freely around the bearing center. And that’s how it aligns itself.
They can correct shaft misalignment more than any other type of plastic ball bearing and that’s what makes them popular for sophisticated devices these days.
As the name suggests, they’re smaller versions of plastic bearings and are required for small diameter parts and lighter applications. Even though they’re small, they’re built to support the load they bear and perform well in high-precision equipment and applications too small for other types of plastic bearings.
Most engineers and technicians don't expect plastic ball bearings to be as reliable as their metallic counterparts. But the opposite is the case. While this kind of bearing can withstand heavy loads, high-speed and high-temperature applications, they also provide corrosion resistance that helps put less pressure on maintenance teams.
And there are more advantages of plastic bearings:
Slideways is a manufacturer of high quality engineered plastic extrusions and wear components since 1994.
