Cost reduction using Inline Compoundierung for injection molding
Themes: Leichtbau, Process- and Production Engineering
The group Polymer Technology of the University of Paderborn and Arenz GmbH are developing a special injection molding process for the inline compounding of glass fibers into thermoplastic materials. A continuously working single-screw extruder uses a special screw to compound the desired recipe. The focus here is on a gentle and sufficient homogenization of the fibers in the matrix, wherein the fiber damage is reduced by about 50% compared to conventional injection molding. This results in longer fibers in the component leading to improved strength and rigidity. Thus, depending on the application, the use of materials can be reduced or new applications can be developed. The melt is Ieached via a hydraulically actuated hot runner system into sequential reciprocating injection units and then injection molded. The use of two piston injection units reduces the cycle time because the dosing process is cycle-neutral. In addition, the single-screw extruder can operate continuously through the two syringe units, which has been shown to improve melt homogeneity. As a result of the special process better mechanical properties of the component are available, which can be produced with lower material costs. Depending an the recipe, the material costs are 50% lower than those of precompounded material, as this is more expensive than the sum of its components.