Making Industrial Processes More Cost Efficient

Extruder Barrel

Temperature profile in the extruder barrel matters

Too low or too high extruder barrel temperatures cannot be used in production. However, the best barrel temperatures are almost never determined with objective criteria. Temperatures influence the throughput of the extruder besides the melt temperature and several other consequences of extrusion. These relations are fairly complicated, and it is not efficient to determine good temperature profiles simply by trial and error experimentation. Higher throughputs are often limited by limits on the melt temperature.

Systematic experiments followed by development of nonlinear models result in the necessary quantitative knowledge for determining the optimal temperature profiles in a given extruder. This article describes how nonlinear models developed from a limited series of experiments can be used to calculate the best temperature profiles in presence of constraints on melt temperature. The case described in the article is of extrusion of medium voltage power cable insulations of one grade of LDPE compounded with carbon black, from one NXW80-20D extruder of Maillefer Extrusion. The approach proposed in the article was found to be efficient.