Injection molding is one of the processes most commonly used in the development of plastic parts for a wide variety of applications. Before the process starts, you must first develop a mold that will be used for the creation of your parts. The mold features both a core and a cavity.
Once you’ve got a mold built, it gets loaded into an injection molding machine, at which point the process begins. There’s a hopper that contains thermoplastic pellets that get sent through the machine’s barrel, and friction between the rotating screw and the barrel results in the pellets melting. Then, electric or hydraulic toggles close the mold halves and then push them together with a massive amount of pressure.
After this, the rotating screw moves along a predetermined distance, injecting a prescribed amount of the molten plastic into the mold cavity under an intense amount of pressure—thousands of PSI. When the material enters the mold, it cools off and solidifies, conforming to the mold’s shape. By the time it has cooled enough, the mold opens up automatically and the part comes out of the core, being ejected by a series of pins.
To sum this up, here’s a quick step-by-step list of the injection molding cycle processes we just described:
- Material comes into the barrel
- The material in the barrel melts and then gets mixed up
- The material is distributed into particular volumes
- The mold closes up
- The plastic material is injected into the mold cavity
- The molten material cools down, at which point the next cycle can begin preparing
- Once the material is cool enough, the mold opens up, and the part ejects, at which point the new cycle is ready to go, with newly melted and mixed material being put into the mold to repeat the last several steps
There are a lot of benefits associated with the injection molding process. It’s highly repeatable, because of the existence of the molds. The parts you produce will always be essentially identical, so long as the mold doesn’t get damaged. This is an ideal way to establish brand consistency with your products, even with high-volume orders and production.
The process also results in a very low volume of scraps. Other types of manufacturing processes, like CNC machining, result in cutting away a substantial amount of the original material. The waste you get from plastic injection molding, however, generally comes from overflow material that leaks out of the part cavity, or in a few other small areas. You’re not cutting away large sections of material—it’s a much smaller amount of scrap, which means you’re getting more economic efficiency out of the injection molding process. In addition, less scrap is better for the environment, which is something you’ll want to consider in your manufacturing processes.
For more information about the process of injection molding in Utah and everything it entails, we encourage you to contact the experts at D&D Plastics today. We’d be happy to answer any questions you have for our team!
Categorised in: Injection Molding
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