Commonly preferred to metal, molded acetal (polyoxymethylene) is a thermoplastic of choice for mechanical parts like bushings, bearings, gears and chain links. The material’s low-friction coefficient against other metals and plastics, stiffness and good wear properties contribute to acetal’s long-lasting durability.
The two types of acetal, homopolymer, produced as Delrin®, and copolymer, produced as Celcon®, share many of the same characteristics, can be used in similar applications and are included in acetal plastic injection molding. Both are strong, easily machined, and can meet tight tolerance requirements. Either can be colored although acetal plastic is utilized for internal pieces versus external pieces which rely on aesthetics.
Acetal is slippery which gives it exceptional friction resistance resulting in minimal energy loss during interaction with other plastic or metal. Its inherent strength and easy machinability for tight tolerances add to the characteristics that make acetal a widely used thermoplastic. In addition, acetal plastic is:
Commonly found in transportation and electronics, acetal is also widely used in a multitude of industries which rely on moving, mechanical parts coming in contact with each other. For example, acetal gears, acetal sleeve bearings and all types of acetal bearings can be found wherever plastic mechanical parts are used.
The unique wear-resistant properties of the molded plastic make it particularly suited to applications including:
Although a commonly used material with benefits for many applications, acetal has limitations. It can weaken and become brittle with prolonged sunlight UV exposure.
When selecting materials, consider acetal if your application requires internal parts with friction resistance for high-impact performance, stiffness, strength and the ability to withstand wet or dry environments.