Plastic Extrusion 101: What is a Plastic Extruder?

We are surrounded by plastic products. Be it pipes, sheets, or laminates; it is estimated that more than 300 million tons of plastic are produced annually.

You may not realize but plastic extruders play a fundamental role in many sectors, including construction, manufacturing, refurbishment, interior design, and fit-out.

The environmental impact of plastic production is high, and that is where plastic extrusion comes in help. The extrusion process is fast and efficient at producing continuous shapes in various lengths. Products can be produced in large volumes, and there is minimal wastage.

And yet, the importance that plastic extrusion plays in our lives is often underlooked.

This article is part of a much broader series about plastic extrusion. We will dig deeper into this process, starting from the basics and moving on to more technical aspects.

Before reviewing what a plastic extrusion machine is, let’s first review what we mean by “plastic extrusion.”

What is Plastic Extrusion?

Plastic extrusion is a manufacturing process in which raw plastic is melted and formed into a continuous profile.

A plastic extruder enables the creation of such plastic products while also speeding up workflow and output volume. With the same plastic extrusion machinery, you can also ensure a higher consistency through your products, which are continuously made to your specifications.

What is a Plastic Extruder?

An extruder is a device that creates extrusions by pushing or pulling material through a shaped die. The goal is to create a continuous length with a preset cross-section.

A standard plastic extrusion machine consists of the barrel containing the raw material and screws. It is also made of screws that are used to force and combine the material with the barrel. There is not one single type of extrusion. Different variants of this concept apply to a wide range of industries working with different materials.

What are the Types of Plastic Extruders?

There are several different types of extruders, including wet and dry as well as low, medium, and high shear extruders.

With dry plastic extruders, the temperature is increased by using the materials only. “Shear” refers to the action of two parts moving in opposite directions. Shear extruders execute this type of processing to extrude plastic products.

How Does a Plastic Extruder Work?

The extrusion process can be broken down into three main steps:

1. Mixing

2. Melting and extrusion

3. Shaping and cooling

The first step, mixing, consists of mixing all raw ingredients together for plastic extrusion. Raw plastic is then fed into a long barrel-shaped extruder, where any additives - such as colorants - can be added according to the required specifications.

In the second stage, the ingredients are melted all together through heating zones positioned along the barrel. These zones melt the plastic gradually, therefore reducing any risk of overheating and polymer degradation. The molten plastic emerges then at the end of the barrel. During this part of the process, the plastic material is also filtered to ensure the absence of all contaminants in the final product. During the melting and extrusion stage, you can finally see the plastic taking its final shape.

The newly formed plastic is then forced into a die, which provides the final shape to the molten polymer. After this step, the process continues to a cooling zone, where the profile is held in shape by formers and goes through water baths. Shaping and cooling are both essential parts of a more complex plastic extrusion process. They both ensure that the plastic product hardens upon cooling to maintain its desired shape.

These are the three main stages of the plastic extrusion process. However, once the plastic material has taken its final shape, it is then processed and cut into smaller pieces according to the original product design.

The exact components of a plastic extruder depend on the plastic extrusion process they follow. However, the most common components include the following:

1. Extruding zone

2. Sizing zone

3. Cooling zone

4. Processing zone

5. Cutting zone

What Next?

If you need to extrude plastic, make sure you choose the right manufacturer to find high-quality products at competitive prices. We at Boyu have over 20 years of experience and have earned more than 60 patents for our plastic extrusion machinery.

We’re a leading plastic extrusion specialist because of our broad experience and knowledge in the field. We specialize in producing PVC floor extrusion, and we invented our patented SPC floor equipment machinery. All our plastic extruders are highly customizable and designed to fit perfectly in your factory area.

Not all plastic extruders are made equal, and not all of them can get the job done with the standards and specifications that you require. Whether you’re looking for floor extrusion profiles or melt-blown fabric production lines, our machinery can create what you need.

When you decide to work with our plastic extrusion experts, you find the right one-stop solution to cover all your needs. We integrate design, production, sales, and after-sales services. In other words, we’re ready to serve you at our best from day one.