Injection molding is one of the most popular methods for manufacturing plastic parts. It is simple, versatile, and time tested. However, those are not the only reasons why injection molding remains one of the more common methods for making plastic parts.
Here are six major benefits of injection molding in manufacturing. We’ll also explain how injection molding has improved over the years to further these benefits.
High Production Speeds.
Injection molding is efficient and effective, resulting in a fast production rate. Its high production rate (averaging 15 to 120 seconds per part) makes it ideal for mass production. There’s little that can go wrong with it, and there is rarely a need for finishing steps. Just inject into the mold, cool, release and send on to the next step in the manufacturing process. All of this is achieved with relatively little labor output. Most of the molding equipment runs with self-gating, an automated system that keeps production both efficient and fast while minimizing wasted material and supervision requirements.
Because of the simplicity of injection molding technology, it is a low-cost plastic forming process. More time and effort goes into the design of the mold and selection of the plastic formulation than anything else. Once the molds are made and assembled, the production line can be up and running in short order. Then the production line can ramp up. Each mold can be used to make a huge number of parts, resulting in increasingly cheaper final products.
Companies like Rapid Direct are notable for offering both affordable high volume and low volume injection molding. They offer custom injection molding and prototype molds. They can make rapid tooling and prototype molds, so you can go through several generations of injection mold designs before you find the ideal mold for mass production. They are the injection molding China experts, and China’s lower cost of labor means you can afford to make injection molded prototypes to show to your customers and investors.
Injection molding is an option for a variety of plastics, though material selection that affects the strength of the part and the ideal mold design. Injection molding is a great choice if you may want to change the color of the part. You’d simply change the chemical additives to the plastic to get a new color without altering any of the other performance characteristics of the part.
You can also switch between liquid color additives and pre-colored resins to get a consistent finish. If you find that part quality isn’t high enough, you could add fillers or alter other aspects of the design to improve impact strength, tensile strength, elasticity or water absorption. This flexibility minimizes the speed and cost of process changes until you get things just right. Injection molding is also the only option that allows you to use multiple plastics simultaneously via co-injection molding.
Injection molding allows you to create incredibly uniform parts at high speed and with minimal handling. This results in extremely high quality, whether you’re making a simple toy or a complex part. Injection-molded parts can be as strong or stronger than nearly any other plastic part on the market if you use the right ribs and gussets to reinforce the part relative to the stresses it is placed under. If it almost never cracks or fails, your customers will consider it to be high quality. A secondary benefit of plastic injection molding is that you can often eliminate other finishing steps like assembly and painting, each of which creates the opportunity for errors that hurt your quality metrics.
The Ability to Handle Complex Parts.
Injection molding can be used to make very complex parts. For example, you can add a lot of detail to the part as it is made, and it is literally part of the final product instead of something you have to add to it later. Better yet, injection molding does so with high levels of quality and speed compared to multi-stage finishing processes. However, key design elements need to be taken into account to create solid, durable injection molded parts. For example, insufficient wall thickness, poor rib design or bad gate placement will create defective products. This makes good part design essential to seeing the high levels of quality from injection molded parts.
One of the greatest points in favor of injection molding is that it produces relatively little waste. Some injection molding companies are able to reduce their waste production even more by recycling any excess plastic generated. They simply grind up the waste and add it back to the plastic resin stream. This is aside from the most eco-friendly firms using state of the art machinery that produces as little waste as possible. Between computer-aided design and computer-aided manufacturing, the best injection molding facilities rarely need to recycle bad parts.
Plastic injection molding is simple, fast, cheap, efficient and almost everything else you need your plastic part production to be. The ability to make complex parts, the level of quality and environmental friendliness of operation varies between manufacturers.