It’s widely known that plastic injection molding can consistently produce thousands or millions of plastic components or products for OEMs, aftermarket suppliers, packaging companies, and consumer goods manufacturers. Plastic injection molding can produce various products varying in size, complexity, and composition—applications for plastic injection molding range from the automotive, medical device, and commercial filtration manufacturing to home appliances, lawn gardens, and medical equipment manufacturing as well.
Once an engineer has designed a part, a toolmaker will build a metal mold, usually out of steel or aluminum. The mold can have a single cavity or multiple cavities, precision-machined to form the desired part. Part and mold design can be precise, even achieving (or exceeding) a tight tolerance of +/- 0.02mm.
Various polymers, including thermoplastics, thermosets, and elastomers, can be used for plastic injection molding. Pellets or granules of the selected material are heated in the barrel of an injection molding machine until the mixture is pliant enough to be injected into the mold. A ram- or screw-type plunger forces the correct volume or “shot” of material to fill the cavities under pressure while the two halves of the mold are clamped tightly together. The plastic material cools and hardens into the shape of the part, then ejected out from the opened mold so the process can begin again.
There are eight benefits of plastic injection molding.
Plastic injection molding reliably creates a high volume of consistent, high-quality units, and there are several other compelling reasons to consider the process:
1. It enables complex metal-to-plastic conversions, lowering overall part costs by reducing several machining operations into a single molding process.
2. Plastic components are lower in weight than machined or cast metal parts.
3. When plastic instead of metal, corrosion is no longer an issue for products.
4. Plastic injection molds allow greater design freedom for parts because they allow the addition of radii or soft edge areas that would require extra machining (at an additional cost) in metal parts.
5. Another element of design freedom is the ability to create highly detailed parts with complex geometry. Because the plastic material enters the mold under high pressure, it fills the cavity and is pressed against the mold harder than in other molding processes. The plastic will conform to tiny, intricate shapes and details inside the mold.
6. Combining different materials into the same part for more excellent utility with fewer assembly processes is possible. With two-shot molding, you can use hard and soft plastic to create a sealing edge, soft-touch edge, or use two different colors. Insert molding allows a non-plastic component to be incorporated, such as a metal screw built into a plastic cabinet knob.
7. The plastic injection molding process involves a high degree of automation, which can significantly save production costs. Many of the steps can be completed by machines or robotics controlled by a single operator, reducing labor costs and overhead. The process can also be performed more quickly and efficiently, increasing production output.
8. This process generates little to no material waste, as leftover scrap plastic can be re-grounded and reused.
Plastic injection molding reliably produces parts and components economically and efficiently. It also gives you a range of material and design options that can reduce the overall cost by decreasing the weight of equipment or a vehicle and reducing costs associated with its use. It’s time to reevaluate your processes and see how plastic injection molding can benefit your company.
TDL has more than 20 years of experience with plastic injection molding, and our team of experts offers knowledge from various molding and manufacturing backgrounds.
Please request a quote or contact us to learn more.