Selecting the right engineering plastic for bearing and wear applications can make or break your machinery’s performance. Factors like moisture, temperature, and friction dictate which polymer will survive in your specific environment.
To simplify your selection process, here is a breakdown of four of the most heavily utilized engineering plastics, their distinct benefits, and where they excel.
Acetal (Copolymer & Homopolymer)
Acetal is a go-to workhorse for precise components, particularly in damp environments.
- The Benefits: Acetal provides excellent dimensional stability. It is exceptionally ideal for wear applications in wet environments.
- The Limitations: It experiences excessive wear in dry applications.
- Top Applications: Bearing and wear parts, pump parts, gears, solenoid blocks, and dispensing heads. It is heavily utilized in the food processing, medical, and paper processing industries.
PET (Polyethylene Terephthalate)
PET bridges the gap between the strengths of Acetal and Nylon.
- The Benefits: PET combines the excellent wear resistance of Nylon with the superior dimensional stability of Acetal. Unlike Acetal, PET wears well in both wet and dry environments.
- The Limitations: It is inherently a brittle material.
- Top Applications: Scrapers, plungers, tension wheels, valves, and bottling equipment.
Nylon
Nylon is legendary for its toughness, but requires careful environmental consideration.
- The Benefits: In dry applications, Nylon dramatically outwears Acetal by a factor of 3:1.
- The Limitations: Nylon readily absorbs moisture. If used in wet environments, this moisture absorption results in excessive wear and potential tolerance issues due to swelling.
- Top Applications: Bushings, rollers, star wheels, slide pads, and chain guides in construction and conveying equipment.
PEEK (Polyetheretherketone)
When environments get extreme, PEEK is the premier high-performance choice.
- The Benefits: PEEK offers incredible chemical resistance and stability, excellent wear resistance, and a continuous use temperature of up to 480°F.
- The Limitations: It carries a typically much higher cost compared to other standard mechanical plastics
- Top Applications: Valve seats, insulators, pump wear rings, and wafers. It is highly sought after in semiconductor, chemical processing, and high-heat transportation applications.
Need Help Selecting the Right Material?
Choosing between Acetal, PET, Nylon, and PEEK ultimately comes down to the specifics of your operating environment, such as moisture levels , continuous use temperatures , and whether you require dry or wet wear resistance.
At W.S. Hampshire, we specialize in helping engineers select, machine, and fabricate the perfect non-metallic materials for demanding applications. Our team can help you navigate the “word games” of material data sheets and ensure you are using the correct test criteria for your specific industry requirements.
Contact us today to discuss your project or request a material recommendation.