How Do They Extrude That?

We’ve just added Extruded Polypropylene Round Rods to the OnlineMetals inventory, which inspired us to give you the quick ABCs of what happens to the plastic before you machine it, and what you can do once you’ve got it!
How it works:
The extrusion process is used to create all sorts of plastic shapes. (We could have added Extruded Polypropylene Star Rods, but that might make your job a little more difficult!)
The process starts with pellets of plastic, could be polypropylene, polyethylene or one of many others. The pellets are melted by forcing them down a long heated channel and through a die at the end of the channel. The continuous piece of plastic coming out will be the same shape as the hole in the die. This could be round, square or other choices.

Aluminum Extrusion Molds

Aluminum Extrusion Molds

Solid shapes are most easily created by a simple opening die, however, sometimes you want tubes! To achieve this a die is created with an additional piece that is floated in the opening of the negative shape, so there are no breaks in the outer wall of the final plastic piece. Otherwise, you would end up with “C”s instead of “O”s.
What you get:
Extruded Polypropylene Round Rod is a very cost-effective material with outstanding physical, chemical, mechanical, thermal and electrical properties, starting at $1.85 per foot for a .5″ diameter piece.
Extruded Polypropylene Round Rod Now In Stock. Cut-to-size-lengths.

Extruded Polypropylene Round Rod Now In Stock. Cut-to-size-lengths.

More features:

-Now available in sizes .5″ to 1″