Nitrofreeze® cryogenic deburring provides OEM manufacturers and machine shops with a fast, efficient, and reliable way to remove burrs from machined Delrin gears. Cryogenic deburring uses tumbling, freezing, and blasting with a cryogenic-grade polycarbonate media to remove outer diameter (OD) and inner diameter (ID) burrs in a safe, clean process that’s a cost-effective alternative to hand trimming.

Material : Delrin   Description : Gear   Area for Concern :  Burrs on Machined Gear Teeth and ID Cutout

The Challenge

Nitrofreeze was asked to remove both the OD and ID burrs from machined Delrin gears. Delrin, an engineering thermoplastic, is used in precision parts that require high stiffness, low friction, and excellent dimensional stability. Delrin is available in a wide variety of colors, supports CNC machining, and is a good choice for demanding applications such as the gears used in industrial printing equipment.

Delrin can be challenging to deburr, however. Before contacting Nitrofreeze, the customer used brushes and knives in a manual deburring process. Both types of hand tools have their disadvantages. Brushes can cause part discoloration and may require different types of tools for OD and ID burr removal. Knives can gouge parts and affect both surface quality and geometry.

The Solution

Nitrofreeze used cryogenic deburring to remove heavy burrs from the gear’s teeth and lighter burrs from a central hole in the middle of the gear. This process does not affect surface finish or part dimensions. Plus, it’s computer-controlled for repeatable, reliable results. Cryogenic deburring is also more cost-effective than hand trimming, which can be inconsistent across parts.

With cryogenic deburring, machined parts are placed in a chamber, cooled, and impacted with a non-abrasive PC media that’s sized from 0.015” (smallest) to 0.060” (largest). The costs to deburr parts can range from less than a cent to several dollars apiece, depending on part complexity. Lot sizes can range from low-to-high volume quantities. The standard turnaround time is two days after receipt.

The Result

Nitrofreeze cryogenically deburred and then released 125 to 250 pieces of various gear sizes. For the customer, cryogenic deburring saved time and money while supporting key application requirements. With gears, a burr-free surface finish on the teeth is essential for proper meshing and reduced noise and wear. The hole in the middle of the gear also requires a burr-free finish to support attachment to a shaft.