
Plastic Injection
Mold and Molding
Plastic Injection Molding Design
Injection molding is an efficient manufacturing process for mass production of the same parts with strict specifications. CADmize mold designers would balance the quantities, molding efficiency, and the cost, creating the tooling cost-effectively.
CADmize is a product development company, our expertise in both engineering design and molding can make us keep the end in mind, finding the commercial way from the very start.
Cost of Injection Mold
In order to minimize the costs of mold making while maintaining the required quality, you should consider these elements:
Mold size
Mold cost is proportional to mold size, the bigger the envelope of the plastic parts requires a larger mold. The multi-number cavities also increase the size of the mold with a higher price of mold development but will reduce the per-piece cost of each part. CADmize engineer will help you make an economical decision on how many cavities should include.
Machining time
The cost is proportional to time. The size, number of the cavities, and the complexity of geometries influence the machining time. The other factors are mold finishing, tolerance, etc. The steel mold also needs more machining time than that of aluminum.
Material for production life
The mold for a large quantity and long production run requires a high-class mold. Select the right material for mold making. Aluminum is always for prototype mold, low volume production, and pre-hardened steel could wear for a long period. Steel mold has a higher upfront cost but will save money in the long production run.
Mold Complexity
These factors will increase the cost of injection molds: Insert or Overmold, Undercuts, Surface Finish, and Parts Complexity. But these features are usually defined in the front stage of industrial design or mechanical engineering, So it’s important to consider the product definition upfront. CADmize experienced engineers would consider these factors from the very beginning to help you make a better decision.
custom plastic injection mold is an initial investment, It’s expensive and will have a great impact on mass production. There is nearly any place to make a mistake for injection mold manufacturing. The whole process requires lots of attention to ensure the specifications are the right definition. Send us your requirements to get professional advice.
Plastic Injection Molding Process
The injection molding process happens in seconds and can mainly be divided into about 5 steps.
1. Clamping
The mold is composed of two parts- core, and cavity. Install these two parts into the molding machine, and clamp them under strong pressure.
2. Injection
The raw material is fed by a screw and melted into a molten state. Then it is injected into the mold by the pressure generated by the rotating screw
3. Dwelling
Continuously send materials with high pressure, to make sure the molten plastic fills all the cavities and compensates for the withdrawal that occurs when it cools.
4. Cooling
Water cycled through the mold to harden the plastic, During this process, new materials are prepared for the next cycle.
5. Ejection
Open the mold, and eject the solid parts with a bar, or be picked always by robots.
The time spent in the 5 steps above is the injection molding cycle. The injection molding time is also a factor that influences the final product. Contact us to start your plan.
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