What is Plastic Extrusion?

Extrusion is a process where a hot material is pushed through a tool called an extrusion die, a thick, circular steel disk containing one or more openings to create a desired shape and thickness. Extrusion processes are widely used in the construction industry to create useful materials in large quantities.

Plastic extrusion is a high-volume manufacturing process where a polymer material, enriched with additives, is melted and formed continuously. It has proven to be a fast and efficient process for shaping plastic and can produce high volumes of products in various shapes, sizes, textures, thicknesses, and colours. Plastic extrusion is also considerably cheaper than other plastic manufacturing methods.

Different Types of Plastic Extrusion

There are many different plastic extrusion forms, all of which are used for slightly different reasons and the process changes for each.

Tubing Extrusion

Tubing extrusion is a type of extrusion used to create materials such as tubes and pipes. During this process, positive pressure is applied to the material and then pulled into a water tank to be cooled.

Blow Film Extrusion

Blow film extrusion is a type of extrusion used to create materials such as shopping bags. During this process a film tube melt is cooled before leaving the die, creating a semi-solid tube which can be blown to expand into a desired size and film thickness.

Sheet Film Extrusion

Sheet film extrusion is used for plastic sheets or films that are too thick to be blown. During this process the sheet is usually pulled through three or four cooling rolls after exiting the die to be cooled and to regulate the thickness of the sheet.

Over Jacket Extrusion

Over jacket extrusion is used to create wire coating. During this process the wire is pulled through the centre of the die. If adhesion is required between the wire and the coating, a pressure tool is used; to do this, the wire coating is covered in molten plastic whilst in the die and pressurized when exiting. If adhesion is not required, a jacketing tool is used where the wire is covered by the melt as it exits the die.

 

Here at Rayda, we manufacture bespoke products to our customer’s specification or can design a product for a specific purpose using plastic extrusion. If you need any more information on our plastic extrusion or what is discussed in this blog or have any other enquiries, please contact our team.