The extrusion process
Today we started a series of articles to help understand the extrusion process.
In the first place, it is necessary to get the idea of a continuous section profile, this is the general idea that gave name to our company SCT "Secciones continuas técnicas", since a basic process of extrusion tries to manufacture profiles of any length, but the same geometry.
For this process, it is necessary to have the correct features with facilities, staff, machinery, tooling, and raw materials.
Both the facilities and the staff will largely depend on the type of company and the market strategy, but we will focus on three fundamental parts of plastic extrusion:
-Machinery: Extruders are the heart of the line; complex machines that can be simplified to a hot endless screw to melt the different plastics that we load into a hopper. If we go into the complexity of why different models are used or because it is better to work with one screw or another, it will be necessary to have a specialist (hence the staff).
In addition, it is necessary to have a cooling tray, a drag and cutting elements. A line can be as complex as a part requires, with all kinds of sensors and automatisms.
-Tooling: to shape and maintain the different raw materials until their solidification is an essential part of the process. That is why it is necessary to have a specific design and manufacture for each profile of dies and calibrators.
-Raw material: according to the technical requirements of each piece, it is necessary to select a specific raw material between the different options such as polyvinyl chloride (PVC), polypropylene (PP), polyamide (PA), polystyrene (PS), polyethylene (PE) , or thermoplastic elastomers (TPE and TPV).
For example, it is not the same to use polyethylene to make a reference in the automotive sector than polypropylene for lollipop sticks.
In the next article, we will develop the process to understand the extrusion of plastics with our experience and technical capacity.