Plastic extrusions refer to an industrial process wherein materials are extruded by using certain processes to form a specific shape. Plastic, because of its flexibility and malleability, is often extruded into various shapes and sizes for a variety of industrial and commercial applications. These may be thin films, sheets, rods, wire, hose, gaskets, and pipe shaped items. Plastics are used in a wide variety of industrial applications because of their tremendous corrosion resistance properties, their durability and their low cost.
Some popular extrusion methods that are used include: hot extrusion, cold extrusion, co-extrusion, dual or multi-durometer extrusion, impact extrusion, reverse or backward extrusion, and hydrostatic extrusion, etc. Hot extrusion is performed at high temperatures while cold extrusion is performed at room temperatures. Some of the types of plastics that are used in these processes include ABS, acrylic, butyrate, fiberglass, nylon or polyamide, polycarbonate, polyethylene (PE), polyethylene terepthalate glycol (PETG), polypropylene (PP), polystyrene, PTFE, polyurethane or urethane, and PVC.
The process of extrusion is often in the form of a short bar which is pushed through a die, which in turn creates long, flat sheets. In cold extrusion the material is held in place at one end and pulled on the other. The plastic is slowly stretched until it is fully extended without the bonds that are holding it together breaking down. In hot extrusion the material is heated which softens the bonds enough to enable the extrusion process to be performed.
The process of extrusion is also commonly performed with other materials such as bronze, brass, ceramics, composites, rubber, silicone, precious metals, copper, aluminum and even steel. In the plastics industry, extrusion is used to create pipes, rods, rails, seals, bags and other shaped objects. There are certain standards that have to be met by plastic extrusions whenever the finished products are going to be used in the consumer and industrial fields.
You must take care while extruding plastic into a desired shape that the dies used in the process are of high quality. In fact, quality checks must take place frequently while extruding plastics.