PROCESS-CONTROL OF PROFILE EXTRUSION USING THERMAL METHOD .1. MATHEMATICAL-MODELING AND SYSTEM-ANALYSIS

An analytical model based on the heat penetration through the die wall was proposed to calculate the effect of die wall temperature on the flow of polymer melt in profile dies. Model prediction matched well with the experimental data measured from a modified Instron capillary rheometer. The model was applied to an extrusion line with an L-shaped profile die. Dynamic responses of the profile extrusion line based on this die were measured and modeled. The pairing of manipulated variables and controlled variables was analyzed.