Plastic extrusions are produced by a process known as plastic extrusion where raw plastic materials are melted down and then formed into a continuous profile. To extrude plastic into various forms, raw thermoplastic material called resin in the extrusion industry, and in the form of small beads, are loaded into a gravity-fed hopper which is mounted onto the top of an extrusion barrel. UV inhibitors and additives such as colourants are very often mixed into the resin before it is loaded into the hopper.

It is also very interesting how so much friction and pressure builds up inside the heater that sometimes the heater will be shut off. Hence, so much heat is being produced on its own.

Plastic extrusion typically takes advantage of tiny plastic pellets or chips, which are melted at high temperature and slowly poured into a mould. After that process, the die gives the product its final shape or profile and must be designed to allow the molten plastic to flow evenly from a cylindrical profile to the products final profile form. A vast number of different shapes and forms can be created using this process, as long as it is a continuous profile.

The final heated product is then cooled by being pulled through a water bath. When compared with some metals, plastic conducts its heat away approximately two thousand times more slowly, because plastics are very efficient thermal insulators. As soon as the product is cooled it may be cut into manageable lengths or spooled for later use.

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