In one of our previous blogs, we talked about the benefits and uses of plastic extrusion, and how it might be the answer to your problem. But how can you know for sure if you don’t fully understand what it is? Today, we’re going to cut the industrial talk and break the process down for you step by step.
First, let’s start with a general explanation of what plastic extrusion is. Plastic extrusion is a manufacturing process in which thermoplastic material, or raw plastic, is melted down and shaped into a continuous profile. As we mentioned in our previous blog, these profiles can be used for anything from pipes and tubing to window and door frames. Now that you have an idea of what the process is, let’s get into the steps.
A typical extruder consists of four zones: the feed zone, the transition/compression zone, the mixing zone, and the metering zone. First, the raw plastic material is fed into the extruder in the feed zone. In screw extrusion, there is a screw in the center of the barrel that creates pressure as the material goes through the extruder.
In the transition/compression zone, the material is compressed by the screw rotation and the shrinking space it passes through. This, as well as friction and energy transfer from the extruder, heats up the thermoplastic material and it begins to plasticize.
In the mixing zone, the channel the material passes through evens out and the material is completely melted and homogeneously mixed. A special mixing element may be in place to ensure the material is consistently mixed.
Finally, in the metering zone, the material is forced through the shaping die, a small channel that gives the plastic profile its shape, and out of the extruder. The product or extrudate is then cooled, pulled from the extruder, inspected, packed, and shipped. Due to the versatility of die shapes, plastic extrusion can create a variety of different profiles for a variety of industries and uses, making it a popular and useful process.
Trimco offers plastic profiles such as chrome trims, decorative trims, drip rails, and lip guard trims to assist with your next project. With our in-house tooling design and engineering and our customizability, we provide the perfect product every time.