Plastic Injection Molding Manufacturing: How Does It Work?

plastic injection molding manufacturing

Did you know that the world’s largest plastic injection molding machine weighs 585 tons? Modern life as we know it wouldn’t be the same without plastic injection molding manufacturing. Everything from Legos to combs and plastic instruments relies on this important fabrication technique.

Are you curious about how plastic injection molding works? If so, read on to learn more about this manufacturing process.

How Does Plastic Injection Molding Manufacturing Work?

The injection molding process relies on three basic components: the feed hopper, the screw, and the heated barrel.

The Hopper

Workers at a plastic injection molding company begin by taking granules or plastic power and placing it in a hopper. The hopper’s job is to hold the plastic granules and to feed those small parts to a device known as the screw.

The Screw

The frictional action of the screw creates heat that turns the granules into a liquid resin.

Once the resin reaches the right temperature, a technician injects it into the mold cavity. This results in the “injection” part of injection molding.

Heated Barrel

Once the super-hot resin fills the mold, a technician leaves it to cool. The cooling resin then takes the shape of the mold.

The final product will be entirely made from plastic. Therefore, some products introduce materials into the mold that are then encased within plastic.

Plastic Injection Molding Monitoring

Although the process sounds simple, plastic injection molding services are complicated. The process requires constant monitoring in order to maintain quality control.

Special technicians must watch the three basic steps of the process: injection time, cooling time, and change over time.

The Parts Uses

Plastic injection molding companies supply aerospace, medical, automotive, and other industry with critical components.

The technology was developed more than a century ago. Therefore, engineers continue to refine the technology to this day. The products made from the plastic injection molding service serve many industries.


From the moon landings to today’s modern space stations, injection molding has made space travel possible. Plastic is ideal for space because the material is light, durable, and capable of handling the rigors and extremes of space travel.

Consumer Goods

Electronic devices like TV casings and CDs are only possible due to injection molding.


Pill bottles are made using injection molding. Plastic is a non-reacting material, which makes it safe for human contact.

Work with a Trusted Injection Molding Company

Plastic injection molding manufacturing is a complicated and fascinating process that is critical for our modern way of life. At Nova Stevensville, our vertical injection molding machine and 26 horizontal machines work to fabricate a wide range of products for several industries.

By using smart technology and maintaining the highest standards, our clients have come to expect quality and prompt results — every time. So, reach out to our team today to learn how we can serve your company’s needs. We will work to get you an accurate quote.

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