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The students in the class I teach challenged me on my knowledge of polymer injection molding. With them not fully knowing my lengthy awareness of every aspect of Polymer Extrusion I told them whoever wrote a better research paper would receive extra credit. With the news of extra credit in the ears of my students the mission was on. Well here we go, Polymer Extrusion is simply the manufacturing of raw plastic for a wide variety of products such as piping, wire insulation, and plastic sheeting. Sometimes it's even used to make simple items such as adhesive tape. Window frames are products of Polymer Extrusion as well. It all starts with raw plastic beads that are fed into a heated extruder cavity or cylinder.

The temperature inside the cavity is a high 400 degrees F. The cavity needs to constantly be this temperature to match the exact melting point of the plastic beads. Overheating is a problem within the extrusion process.

The screw then rotates eventually forcing the plastic out. The Heat inside the extruder cavity is a high 400 degrees F; it must match the plastic beads melting point. Three heaters are used in most extrusion machines. I always wondered why they needed three heaters.

A big problem in the extrusion process is the problem of overheating. Most often in the extrusion process 3 heaters are used. The plastic is gradually introduced to the three heaters to gradually melt so overheating is not a problem.

Ah! My favorite part, sometimes the friction and pressure are so great there's no need for the extrusion heaters. The friction and pressure maintain the maximum temperature desired for the plastic. After the heat is added it is then time for the cooling fans to be put in place.

It must be tricky trying to filter molten plastic but it's interesting how Plastic manufacturers use the filter to do it. After the molten plastic goes through the filter it's time for the special dye. The die the plastic goes into is responsible for giving the plastic its profile.

Polymer Extrusion Companies are pretty interesting and provide a lot of exterior panels for our community. I once toured a Company in Florida and saw the how the die was added. After the die is added it is time for the plastic to go into a sealed water bath.

Specially designed cooling rolls replace the water bath for more delicate plastic products such as plastic sheeting. If my students don't add that fact I'll send them all to the chokey! After the process the plastic is spooled, coiled, or cut to length. I bet my knowledge of the Polymer Extrusion Process will overcome my pupils.