Using the same configuration as the filament extrusion line, our Haake is also capable of measuring the melt strength of thermoplastics with the Göttfert rheotens. The rheotens, is mounted underneath the capillary die. When a constant flow of polymer is established, the rheotens draws on the extruded filament. the force that is needed to extend the extrudate a certain length is proportional to the melt strength of the polymer used.