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It's always important to know the ins and outs of every difficult process right? To me mostly yes, but the other day my friend was talking about what he learned about in his college class, something by the name of plastic manufacturing. Interested to learn more on a college worthy topic I listened to his brief description. I was fascinated by how many simple things can be made out of plastic, things I never took a second to think was plastic! I learned that Plastic extrusion is a manufacturing process when plastic is put into a large heater, melted, shaped, and cut to length. As I was eager to learn a little more I did some research and asked a couple people their knowledge on plastic extrusion. The results were a lot of people had mixed reactions on knowing what it was or not!

But now after lengthy research I can call myself a plastic extrusion information center. The production of plastic being heated, melted, shaped, and cut is used for the production of plastic sheeting, wire insulation, adhesive tape. A lot of window frames are even made from plastic extrusion.

In the plastic extrusion process small bead forms of plastic are fed into a heater extruder cavity or cylinder. In some cases ultra violet inhibitors may be added to the raw plastic beads as well. Once inside the heater the small beads enter the extruder cavity towards a screw mechanism. The screw rotates forcing the plastic material through the extruder.

This was an interesting fact; inside the heater is a whopping 400 degrees F, due to the heater having to be the same temperature of the plastic materials melting point. Over heating is a big issue in plastic extrusion and there's one way to make it stop!

Friction and pressure serve as separate source of heat that is independent from the heaters. And in some cases the friction might conduct so much heat the actual heaters for the extruder are shut off. The pressure and friction maintain at the desired temperature.

The die it is placed into is responsible for the plastics profile, after the die the plastic must be cooled. It's cooled by a sealed water bath; the water bath protects the newly formed product in its still molten state. If the plastic was being formed into a sheet a specially designed cooling roll replaces the water bath.

This process is also called the Polymer Extrusion Process. The program I intensely payed attention too showed every aspect I was willing to learn about this process. After the cooling is complete, it's time for the plastic to be cut to size. The product can also be spooled, coiled, or cut to length. Materials such as Aluminum and rubber are examples of extruded parts of the plastic. The extrusion process is used every day for household items, city structures, and simple things as tape. But no one realizes that injection molded products are made from extruding plastic. After everything is cooled, it is now time for the plastic to coiled or cut to length.