In conjunction with the material selected, the most important part of the extrusion process is the die that is created that forms the shape for the final part. Knowing what is possible and what can cause issues is critical in developing effective die designs. There are guidelines that can help you to understand what makes dies work well and what can cause issues.
The best place to start is in understanding how a die is part of the extrusion process. The extrusion process starts with pelleted plastic material, such as PVC, vinyl, high density polyethylene (HDPE) or butyrate, placed at the beginning of the extrusion line where it is forced down the line. The movement occurs because a screw pulls the plastic pellets out to the bin and presses them into the extrusion line. During this process, the combination of the friction of the screw and external heat elements causes the plastic to become soft and pliable. The pliability of the material is what allows it to flow through the die. These are critical steps before the plastic material gets to the area of the line where it is formed by the die.
A die is a tool used by extrusion engineers to get the shape that they want on a final product. Generally made from a metal plate, the die offers the reverse of what the product will look like as it creates the spaces within the stream of the molten plastic material. Much the same way that foods, such as spaghetti, are formed, the die is the way that the plastic is shaped into the final product. After the plastic flows through the die, it is quickly cooled and cut into the desired length before it is packaged and sent out to the customer.
At Extrudex, we can assist you in determining the best materials and processes to get the results that you need for your industry. We offer custom die design, top notch customer service and rapid prototyping. Call us for expert advice today!