Plastic Fasteners Key Terms

Understanding key terminology related to plastic fasteners

By Kim Finn

Plastic fasteners offer a sound alternative to their metal counterparts. They often cost less than metal fasteners, and they also have to meet the same fit and dimensional thread class dimensions. Plastic snaps, screws, bolts, clips and other fasteners serve useful purposes in applications where end-use features like weight, electrical, thermal, environmental, chemical and optical are important criteria.

Whether you're in the market for, plan to sell, or intend to manufacture threaded or nonthreaded plastic fasteners, review key terminology connected to plastic fasteners so you make better informed business decisions. This guide addresses six terms: injection molding, Ultem, self-reinforced polyphenylene, Uni-Screw, Canoe Clips and Christmas Tree Clips.

Injection molding

With regard to plastic fasteners, injection molding is a manufacturing process in which melted plastic is forced into fastener molds where it solidifies in its final shape.
Try: Learn more about the injection molding process and presses used by The Rodon Group, a manufacturer of plastic fasteners and other plastic components.

Ultem

Ultem is an amorphous polymer with excellent mechanical strength. It serves as a great replacement for metal fasteners because of its radiation resistance, natural flame retardant and microwave transparency properties. Ultem fasteners work well in water and hot air environments, as well as in medical and electronic applications. Ultem is the trademark name for polyethermide.
Try: Read more about Ultem 1000 and Ultem 2300 fasteners at the Craftech Industries website.

Self-reinforced polyphenylene (SRP)

Self-reinforced polyphenylene is an amorphous thermoplastic with high compressive strength and used in injection molding, compression molding and extrusion processes. It makes a suitable alternative to metal fasteners. The brand name for SRP is PrimoSpire.
Try: Get more information about PrimoSpire SRP at the Professional Plastics website.

Uni-Screw

Uni-Screw is the brand name of a metal screw-head and driver design that was developed by British engineers. It incorporates a series of tiered recesses that helps eliminate stripping and cam-out with high torque applications, reduces tooling costs and enhances assembly productivity. One of the primary advantages of the Uni-Screw is that it requires only one driver for several screw sizes. Volt Industrial Plastics and Uni-Screw Worldwide combined efforts to develop the Uni-Screw in plastic.
Try: Learn more about the Uni-Screw in Plastic at the Volt Industrial Plastics website.

Canoe Clips

Canoe Clips are lightweight push fasteners that snap into place and make great replacements for metal rivets and screws. They're best used in permanent applications, although they will withstand occasional removal.
Try: View a diagram of different Canoe clip head styles at Thread-Rite Screw Products.

Christmas Tree Clips

Christmas Tree Clips are plastic, push-in fasteners with a ribbed shank design that works well in either prepared or unprepared holes.
Try: View diagrams of a Christmas Tree Clip at the ITW Fastex website. Scroll down to read about different styles of Christmas Tree Clips at Fastening Systems.