Teflon machining is used to produce components for the aerospace, electrical, medical, and processing industries. Filled and unfilled grades of this fluoropolymer are used in machined parts such as beads, bushings, and bearings; seals, gaskets, and O-rings; gears, guides, and fittings; and valve bodies and valve seats. Machined Teflon is also used for arc shields and electrical insulators. Teflon is a well-known brand name for polytetrafluoroethylene (PTFE), but there are other trademarked PTFE resins.
Nitrofreeze® cryogenic deburring removes PTFE burrs, raised areas on machined Teflon parts that can interfere with sealing or assembly. Compared to manual deburring, cryogenic deburring is safe, quick, and efficient. This computer-controlled, automated process can deburr batches of components instead of just a single part at a time, and without affecting critical dimensions. Contact Nitrofreeze® to discuss your Teflon deburring project or keep reading to learn why PTFE is a good candidate for cryogenic burr removal.
What is Teflon? What is PTFE?
Teflon is both a semi-crystalline thermoplastic and fluoropolymer. Because of its molecular structure, it has high impact resistance. Because of its fluorine additions, it has strong resistance to chemicals. Teflon also withstands extreme temperatures, including high heat, and resists wear and abrasion. Importantly, Teflon is also an excellent electrical insulator. Teflon is a brand name from Chemours, but PTFEs such as Dyneon (3M) and Fluorosint (Mitsubishi Chemical Advanced Materials) are also available.
How is Teflon machined?
Teflon supports CNC milling, drilling and turning; however, it’s difficult to achieve tight tolerances with this soft, dense material. That’s because PTFE has a high coefficient of expansion and is prone to stress creep. Post-machining annealing can reduce material stresses, but the problem of burrs remains. Even when machinists use sharp, narrow tools and non-aromatic, water-soluble coolants, achieving an optimum surface is challenging. Therefore, deburring is often required.
Why use cryogenic deburring with machined PTFE parts?
Cryogenic deburring safely and cleanly removes Teflon burrs and surface imperfections without affecting the part’s structural integrity. This includes PTFE chips, flakes, and raised or pointed areas. With manual deburring, there’s a risk that Teflon parts could experience dimensional changes under excessive pressure from trimming tools or industrial brushes. By contrast, cryogenic deburring removes only the burrs and surface imperfections, and without changing part geometry or affecting critical tolerances.
How does Nitrofreeze® cryogenic deburring work?
Cryogenic deburring uses very low temperatures and polycarbonate media to remove burrs from PTFE machined parts. With this machine-based process, batches of parts are placed in a chamber and cooled to very low temperatures so that the burrs become brittle. These surface imperfections are impacted with the non-abrasive media for quick and easy removal. Part edges are maintained without rounding, little or no dust or residue remains, and this automated process provides part-to-part consistency.
How is dry ice deburring different?
Cryogenic deburring uses polycarbonate media that comes in different sizes and maintains its aggression with holes are small as 0.015” (0.381 mm). The parts also tumble against each other. Dry ice deburring blasts batches of parts with dry ice instead and can target specific areas, including holes smaller than 0.015” (0.381 mm). Dry ice blasting, as it’s also known, is effectively media-less because the dry ice particles turn into a gas or vapor (sublimation) after impingement.
What’s the best way to deburr machined Teflon or PTFE?
What’s the best way to deburr machined Teflon or PTFE parts? Contact the experts at Nitrofreeze® to discuss your application. No job is too large or too small, and our standard turnaround time is two days after receipt! If your Teflon / PTFE part is a viable candidate, we can perform sampling to demonstrate the process we recommend. We can also save your recipe for future batches of the same part. The consultation is free of charge, so send us your part drawings, photos, or samples to get started.
(508) 459-7447 x 105 | email@example.com