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The article explains what a triple-screw extruder is and how adding a third screw significantly improves plastic mixing and compounding. Compared to twin-screw extruders, triple-screw extruders offer multiple intermeshing points, resulting in better plasticizing, higher throughput, superior dispersive and distributive mixing, and improved energy efficiency. They excel in producing highly filled masterbatches with greater toughness and uniformity. The design also provides better degassing and even allows in-situ molecular grafting for specialty applications like PP foam beads. While twin-screw extruders remain ideal for precision reactive extrusion and small-batch production, triple-screw extruders are recommended for large-scale, high-capacity manufacturing, especially for materials requiring complex mixing and high filler content. The article concludes that triple-screw technology has strong potential in advanced compounding and future polymer processing.
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This article shares practical methods to improve and control the melt flow rate (MFR) of TPE (thermoplastic elastomers) during pelletizing and injection molding. Key strategies include adjusting the oil content in SEBS/SBS base resins, optimizing formulations by selecting higher MFI PP/PS and adjusting fillers and lubricants, and fine-tuning processing conditions such as temperature, screw shear rate, injection speed, and holding time. Together, these approaches help achieve better flowability, stable processing, and high-quality TPE products.
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To prevent common injection molding defects in TPE and TPR products—such as flow marks, sink marks, and gate breakage—manufacturers can improve melt strength by adding 5–15% TPV during pelletizing. TPV modification enhances molecular chain entanglement, improves dimensional stability, and slightly increases hardness while maintaining thermoplastic processability. For best results, TPV should be uniformly blended using a twin-screw extruder, with process adjustments made to account for higher melt viscosity. This approach helps achieve better product quality and reduces defects in thin-walled, complex molded parts like medical grips and precision seals.
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This article explains how plastics processors can improve purging efficiency by combining high-quality purging compounds with well-managed processes. It highlights common mistakes—like using cheap virgin resin, choosing purging compounds only by price, and ignoring supplier instructions—that often reduce cleaning effectiveness. The article also emphasizes the importance of consistent training, process monitoring, and choosing the right supplier to reduce downtime, extend equipment life, and improve profitability in extrusion and injection molding operations.
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This article explores common causes of die hole blockage in underwater pelletizing systems—especially when processing engineering polymers like PET, nylon, and polycarbonate—and outlines three key strategies to reduce cleaning frequency: automating the startup sequence to avoid premature cooling or smearing, optimizing die heating and insulation to prevent uneven temperature distribution, and maintaining stable extrusion conditions using melt pumps and continuous screen changers. These solutions help ensure consistent pellet quality, reduce downtime, and improve overall production efficiency.
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This article explores the five main factors that cause wear in twin-screw extruder barrels and screws: abrasive wear from fillers, corrosive additives, high-intensity wear zones, extreme operating conditions (temperature and pressure), and internal moisture or gases. It emphasizes the importance of choosing high-performance materials—especially powder metallurgy steel—to extend component lifespan, reduce maintenance costs, and improve production efficiency in plastic compounding operations.
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This article explains how to identify and resolve resin degradation in single screw extruders. Resin degradation, often caused by stagnant flow and high temperatures, leads to product contamination. The solution involves step-by-step screw removal, inspection, and design analysis—especially addressing issues like small thread radii, improper groove dimensions, and poorly designed mixing elements that cause Moffatt eddies and stagnation. Preventive measures include proper screw design, temperature control during shutdowns, and avoiding deep or narrow grooves that trap resin.
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This article outlines the main types of twin-screw extruders—classified by screw rotation direction, structure, engagement, purpose, and size—and explains how to choose the right model based on material characteristics, production scale, and efficiency needs. It emphasizes that factors like screw design, speed, temperature control, and process parameters significantly affect output and performance.
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This article explains the advantages of side vacuum exhaust systems in plastic extrusion. Unlike traditional top-mounted systems, side vacuum systems prevent material overflow by positioning the vacuum port laterally, improving process stability and reducing maintenance. It also clarifies that a stable negative pressure—not higher vacuum strength—is key to effective degassing. Factors such as temperature control, screw speed, and screw design also significantly impact performance. The side vacuum system is especially suitable for high-volatility materials where reliability is critical.
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This article explains the principles of screw configuration in different sections of a twin-screw extruder. It outlines five key process zones—feeding, melting, mixing, venting, and metering—and describes the role of various screw elements such as conveying screws, kneading blocks, and mixing threads. It emphasizes that selecting the right screw combination based on material properties and processing needs is essential for achieving high product quality and efficient operation.