A computational fluid dynamics (CFD) model has been developed to compute the pressure, temperature, velocity, viscosity and viscous dissipation in the high-density polyethylene (HDPE) extrusion process. The numerical approach agrees fairly well with the experimental data recorded during the extrusion process of the material. The extrusion spider die was designed to produce high-density polyethylene pipes of 32 mm inner nominal diameter and 2.4 mm thickness. In order to investigate if the spider legs are able to perform under the pressure occurred using the maximum flow rate provided by the single screw extruder of this study, a stress analysis was conducted on a single spider leg. This fluid-structure interaction (FSI) problem was solved using the COMSOL Multiphysics software. Finally, the results obtained from the FE analysis were applied in the design and fabrication of the spider die, selecting IMPAX (tool steel) as fabrication material.
Part of the book: Extrusion of Metals, Polymers, and Food Products