Cryogenic Deflashing for Molded Acetal Plastic Parts

Introduction to Acetal Plastic

Acetal plastic, also known as polyoxymethylene (POM), is a thermoplastic polymer that is used in a wide range of industrial and consumer applications. It is characterized by its high stiffness, low friction, and excellent dimensional stability. This material has good chemical resistance; it can withstand high temperatures and high loads.

Some common uses of acetal plastic include gears, bearings, rollers, bushings, and other mechanical parts that require low friction and high wear resistance. It is also used in electrical and electronic applications, such as insulators and connectors. In addition, it can be found in consumer goods such as handles, toys, appliances, toys, utensils, among others.

Acetal plastic is produced by polymerizing formaldehyde and can be produced in a variety of forms like rod, sheet, film, and more. The most common variants are homopolymer and copolymer.

How Is Acetal Injection Molded?

Acetal (polyoxymethylene or POM) can be injection molded using the following basic steps:

1. Material preparation: The polymer pellets or granules are loaded into a hopper and then fed into an extruder. The extruder melts the polymer and pushes it through a nozzle into a heating chamber.
2. Mold clamping: The two halves of the mold are closed tightly, and the clamping mechanism is activated to hold the mold securely in place.
3. Injection: The molten polymer is injected into the mold under high pressure. The pressure helps the polymer flow into all the intricate details of the mold and ensures that the part has a good surface finish.
4. Cooling: The mold is cooled with water or air to solidify the polymer and form the desired shape. Cooling time will depend on part geometry, thickness and the mold temperature.
5. Ejection: Once the polymer has solidified, the mold is opened and the part is removed. Any flash (excess material) will be removed manually or with one of the many deflashing solutions available today.
6. Inspection and packaging: The parts are inspected to ensure they meet the desired specifications, and then they are packaged and shipped to the customer.

Depending on the complexity of the part, the injection molding process can be automated to produce large quantities of parts with high precision and uniformity. And the process can be optimized in terms of temperature, pressure, and cooling time to get the desired properties on the final product.

Does Molded Acetal Plastic Flash?

Acetal plastic, also known as polyoxymethylene (POM), is a thermoplastic material that can be molded into various parts. Flash is a term used to describe excess material that extrudes from the mold along the parting line and other locations during the injection molding process.

Flash can occur during the injection molding process, even when using high-quality molds and proper processing conditions. However, the amount of flash present on a part can be minimized through proper mold design and process optimization. Additionally, the use of release agents and proper mold maintenance can also help to reduce the occurrence of flash.

Cryogenic Deflashing for Molded Acetal Plastic Parts

Molded acetal plastic parts can be cryogenically deflashed. Cryogenic deflashing is a process that uses cold temperatures to remove flash (excess plastic material) from injection-molded parts. The process typically involves subjecting the parts in a gaseous nitrogen atmosphere, which cools the plastic to low temperatures. The cold temperatures cause the acetal flash to become brittle, which makes it easy to remove. This process is most commonly used on parts that have small or intricate geometries that are difficult to remove flash by hand or using mechanical means.

Are you interested in sending your Acetal parts for a free cryogenic deflashing evaluation? Please contact us at (508) 459-7447×105 or email us at info@nitrofreeze.com.