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Molding Parts with Delrin

August 5th, 2022

Much of the success in designing a custom plastic injection-molded component comes from using the right material for the job. Both the intended use of the part and its design help determine the properties that its material should have for effective manufacture and use. As a result, at Southwest Plastics we frequently use specialized materials to achieve superior results for our clients. One such material is Delrin®, a high-performance acetal resin produced by DuPont.

Delrin® Acetal Homopolymer

Delrin® is an acetal homopolymer (Polyoxymethylene POM) that combines low friction and high wear resistance with high strength and stiffness, making it ideal for injection-molded parts intended to replace metal. High-load mechanical applications where it can be successfully used include gears, door systems, safety restraints, conveyor system components, medical delivery devices, and more. Delrin® has a wide operating temperature range (from -40 degrees C to 120 degrees C), good colorability, good electrical insulating characteristics, and excellent dimensional stability in high-precision molding. It also mates well with metals and other polymers.

Although Delrin® is so well known that the name is sometimes used interchangeably for acetal resin in general, there are key differences between acetyl copolymers and Delrin®. As an acetal homopolymer, Delrin® has a larger, uniform crystal block structure that provides better chemical bonding than acetyl copolymers. That imparts higher tensile strength, stiffness, creep and fatigue resistance, and much higher impact resistance. The combination of these mechanical properties give Delrin® significant advantages for part design and production, including:

·       Thinner wall sections at the same physical part performance

·       Lighter parts

·       Less material used

·       Improved mold filling

·       Shorter molding cycle times

·       Increased design flexibility

·       Potential for reduction in part production cost

While Delrin® is the stiffest unreinforced engineering polymer available, DuPont also offers dozens of specialized varieties of the resin that have been treated or reinforced to enhance selected characteristics. These include glass-reinforced polymers for extra strength; UV-stabilized polymers; polymers modified with PTFE fibers, lubricants, or Kevlar® for low wear and low friction; and polymers designed for food contact applications.

Due to its properties, Delrin® is typically used for demanding applications in the automotive, industrial engineering, electronics, consumer goods, domestic appliance, and sports industries. Of course, to get the most out of the advantages Delrin® can provide, you need an experienced manufacturing partner who can help determine the ideal type of material to use for your project. Southwest’s engineering team can help you select the right variety if your part has unusual requirements.

Industry-Leading Experience and Service

If you’re searching for the right manufacturer for your custom plastic molding projects with Delrin®, Southwest Plastics has the expertise and experience you’re looking for. As a proven U.S.-based engineering and manufacturing firm, we have worked continually over the years to keep our knowledge and capabilities at the forefront of our industry to provide top quality service at competitive prices to our clients in the automotive, aerospace, healthcare, electronics, telecom, and defense sectors. Our engineering department has the knowhow to solve challenging design problems and optimize your part design to take advantage of the features of materials like Delrin® for smoother manufacturing and better performance.

Southwest prides itself on white-glove customer service on every order, whether it’s a design prototype or a large production run. When it comes to quality, schedule, and price, we don’t believe in compromise—we’re dedicated to providing value, reliability, and service to all our customers. We also put the utmost emphasis on protecting your valuable intellectual property, ensuring that you retain control over your design and intellectual property rights. Based in Southern California, we can provide fast turnaround times, flexibility, dependability, quality, and reduced shipping costs that overseas manufacturers just can’t match.

Whether you’re looking to re-shore your injection molding projects or simply need a highly skilled manufacturing partner to produce specialized parts to exacting standards, Southwest Plastics is your source for quality parts custom-made in America. For more information about Delrin® or to find out how Southwest Plastics can support your manufacturing needs, contact us here.

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