In the plastics industry, twin screws are at the very heart of the extrusion process that transforms raw materials into rigid PVC pipe or profile. These highly engineered components are integral to transporting, compressing, mixing, heating, cooling, shearing, and pumping a variety of viscous substances through dies into highly structured products. As such, the screws are also the primary factors in production throughput and final quality.
Given the critical role that screws play in the extrusion process, when it inevitably comes time to replace them, many rigid PVC pipe or profile manufacturers continue to underestimate the impact of an optimized screw design. With the variability in raw materials, recipes, additives, and fillers utilized, screws are not off-the-shelf parts that can be simply “switched out” based on category of product.
An optimized design, on the other hand, is a consultative approach in which every parameter of the process is evaluated to create a customized solution that fits the application. When coupled with a replacement screw supplier with an extensive knowledge base of designs and an intimate understanding of extrusion processes, screw replacement morphs from a task into an opportunity for rigid PVC extruders to refine their process, resolve current processing and product quality issues, and even ensure that the next replacement is further in the future.
We have accumulated a database of materials, formulations, parameters, and OEM designs. In addition, the company has developed proprietary simulation software to optimize counter-rotating screw design based on specific raw materials, compounds, formulations, temperatures, and operating conditions.
Why Design Services Matter
A screw manufacturing company that offers screw design services can be a valuable resource. With years of experience and specific manufacturing knowledge a screw designer can provide recommendations that improve efficiency and performance. A screw design can pay huge dividends.
Performance Driven Screw Design
The type of material you are processing and your desired production rate are key performance considerations. Whether it is adjusting material flow rates, controlling mixes or temperatures we have the knowledge to make effective and smart recommendations. If you can define what you need to achieve we can design and manufacture a new screw that meets the requirements.
Material Selection Considerations
Whether the twin screws are conical or parallel, wear life is an issue when extruding challenging materials. With rigid PVC, extruders generally require screw replacement in one to four years because of abrasive or corrosive fillers.
When designing a new screw or barrel, you have the opportunity to select the screw steel and finishes that will provide optimal wear resistance and longevity. We have a wide variety of base materials, hard surfacings, platings, coatings and heat treatments to choose from for your new screw. Our screw design experts can introduce material and finish options including explaining the advantages offered by each of these.