Molded PEEK Parts - Cryogenic Deflashing

Cryogenic Deflashing for PEEK Plastic


Cryogenic deflashing for PEEK plastic removes mold flash from parts made of polyetheretherketone (PEEK), an engineering thermoplastic that provides chemical resistance, mechanical strength, and dimensional stability. Flashing is sometimes a cosmetic issue, but PEEK molders need to avoid surface defects that can interfere with a component’s performance. Cryogenic deflashing removes surface imperfections without affecting part tolerances and offers numerous advantages over hand trimming.  

Molded PEEK Parts: Advantages and Applications

PEEK is a high-performance plastic that maintains its strength and stiffness over a wide range of temperatures. Applications for molded PEEK parts include aerospace components, medical instruments and devices, and electrical connectors. PEEK plastic is available with a UL 94 V-0 flammability rating and can have very low smoke and toxic gas emissions when exposed to flame. PEEK plastics can be unfilled (virgin), glass-filled, bearing grade, or FDA compliant. Many proprietary brands are available.

Injection Molded PEEK Parts and Flashing

During injection molding, PEEK plastic can leak between the mold’s parting line, the dividing line that separates the two halves of a mold. In addition to worn tooling, the causes of mold flash include improper venting, inadequate clamping pressure, poor sprue bushing support, and excessively low viscosity. Because of PEEK’s stiffness and strength, molded PEEK parts are susceptible to hard residual flash that can be difficult to remove by hand. Fortunately, there’s a better way to remove these surface defects.     

Advantages of Cryogenic Deflashing for PEEK Plastic

Unlike hand trimming, cryogenic deflashing is a computer-controlled batch process. It’s faster, more accurate, and less labor-intensive than manual operations where workers handle a single part a time. Cryogenic deflashing also provides a higher level of consistency while maintaining part integrity and critical tolerances. The cryogenic-grade polycarbonate media that’s used is non-abrasive and comes in different lengths and diameters to meet application-specific requirements. 

Case Study: Cryogenic Deflashing for Molded PEEK Aerospace Parts

An injection molder asked Nitrofreeze® to remove flash from PEEK aerospace parts. These components are seated within an electrical housing and must be free of surface defects that can affect performance. The molder required that flash extend no more than 0.003” from the part’s surface. Production volumes were between 400 and 800 pieces per week. The injection molder had tried hand trimming, but manual deflashing produced unacceptable nicks along the parting lines and ejector pin locations.        

Nitofreeze® evaluated sample parts and determined that these molded PEEK components had parting line flash that extended 0.012” from the surface with a thickness of 0.005” at the base. The mold flash at the three ejector pin locations was 0.020” tall and .004” thick. Nitrofreeze® developed proprietary processing parameters for its cryogenic deflashing system. Initial sampling revealed that these parameters reduced parting line flash and ejector pin flash within tolerance.

Nitofreeze® then extrapolated a process for production runs of over a hundred parts per cycle. With hand trimming, the PEEK molder reported cycle times of one minute per piece. With cryogenic deflashing, the molder leveraged batch processing and was able to save nine labor hours per week. The transition to Nitrofreeze® cryogenic deflashing eliminated scrap, too. Compared to manual operations, cryogenic deflashing cut costs by 83.4%.  

Cryogenic Deflashing for Your PEEK Plastic Parts

Cryogenic deflashing from Nitrofreeze® is ideal for all grades of PEEK materials, including FDA approved grades used in medical implants.  Contact the experts at Nitrofreeze® to discuss your application requirements. If your part is a viable candidate for cryogenic deflashing, we can perform sampling to demonstrate our process. The consultation is free of charge, so send us your part drawings, photos, or actual samples of silicone parts.

To get started, contact Nitrofreze® at the phone number and email listed below.

(508) 459-7447 x109 |