The plastic extrusion process involves melting and forming raw plastic into a continuous profile. It is most commonly used to make items such as pipe/tubing, weatherstripping, fencing, deck railings, window frames, plastic films and sheeting, thermoplastic coatings, and wire insulation.

Although all of the things mention above are created using the extrusion processes most of them are used one of the many types of extrusion processes available. In this two-part post we’ll look at six types of extrusion process and what they entail.

Sheet (Film) extrusion

This technique is used to make flat plastic sheets and films from different types of resin. In this process the plastic is put through one or more sets of rollers after exiting the die to gradually thin the material to the desired thickness. Depending on the thickness of the sheet, they are used for a wide variety of applications. From truck bed liners, to playground equipment and deli containers these extruded sheets of plastic make their way into everyday life without us even noticing.

Blow film extrusion

This is another film based extrusion technique which is used mainly in the manufacture of products like plastic bags. The process involves inflating a cylinder of film created by the die creates a cylinder with compressed air. Blow film extrusion is the preferred method for making plastic shopping bags because it creates more consistent wall thickness than sheet extrusion.

Over jacketing extrusion

The jacketing process is used primarily for coating wires. It involves pulling a bare wire (or bundles of jacketed wires, filaments, etc.) through the centre of a die similar to a tubing die. Depending on the application many different materials are used for the process.

Lookout for part 2 of our post where we look at three more plastic extrusion techniques.

Plastic & Chemical Trading together with our international partners deliver world class extrusion solutions to Southern Africa. If you’re in the market for a plastic manufacturing solution that can stand the test of time, contact Plastic and Chemical trading today.