Some melt flow and mechanical design aspects of large extruders

This paper examines two aspects in the design of large extruders. An analysis of the thermal problems in the flowing melt is given in terms of dimensionless groups and the results are applied to the scale-up problem in extruder design. An analysis of the mechanical stability of extruder screws is also given including the effect of axial buckling and whirling. The results are examined as a possible limitation on extruder dimensions.