Advantages of High-Performance Polymer Bearings and Bushings

Plastic is a fantastic material that is used in practically everything from playground equipment to lawnmowers to vehicles. But what about as a bearing or bushing?

Many engineers resist using plastic bearings, thinking they won’t stand up to harsh environments, extreme temps, heavy loads, or high speeds. Some engineers believe in metallic bearings and are reluctant to change. However, high-performance plastic bearings are turning heads and changing minds

Standard Metal Bearings

Polytetrafluoroethylene (PTFE)-lined metal bearings are made up of a thin, self-lubricating layer, embedded with PTFE, which is permanently bonded to an aluminum housing. However, the liner isn’t replaceable and can be scratched off by contaminates, which results in metal-to-metal contact between the bearing and shaft. This increases the coefficient of friction (COF), accelerates wear rates, and increases the risk of shaft damage.

How about injection molding the entire bearing or bushing from FEP, PVDF, or PFA?

High-Performance Plastic Bearings

With advancements in resins, plastic bearings are gaining in popularity because they are more versatile, economical, and more corrosion-resistant than metal alternatives. PEEK, Torlon® (PAI) PBI (polybenzimidazole) Ultem® (PEI), and PPSU (polyphenylsulfone) are all available as material options and suitable for use in plastic bearings. Plastic bearings are made of a thermoplastic alloy with a fiber matrix and solid lubricants, which account for their superior strength and consistently low COF.

High-performance plastic bearings offer a great many advantages:

Cost savings, first and foremost. High-performance plastic bearings reduce overall cost because they resist wear, reduce maintenance costs, and can replace more costly alternatives.
No need to lubricate. These bearings are self-lubricating, with lubricants embedded in the tiny chambers of the composite material. This eliminates the costs of both additional lubricants and continual maintenance.

Plastic bearings can be reinforced with carbon fiber or fiberglass and can operate continuously at temperatures between -40°F and 500°+ F. But their thinner walls are better at dissipating heat. Plus, they’re less likely to deform under heavier weights.

Corrosion Resistant. Plastic bearings are specifically designed to operate in harsh environments, surviving daily washdowns and caustic chemicals. Plus, their self-lubricating nature eliminates seal failure and contamination.
Consistent COF. These bearings are designed to maintain a low COF over their lifetime, while their metal-backed counterparts can become scratched and increase the COF.
Lighter weight. Plastics are significantly lighter than their metal alternatives, which can be up to five times heavier.
Plastics can dampen vibrations with lubrication, becoming virtually silent.

To learn more about high-performance plastic bearings from Pexco, please visit our website at www.pexco.com/materials/high-performance-plastics.