Effect analysis for compensating viscosity fluctuations by means of a self-optimising injection moulding proceb

Abstract

As the conventional control of the injection moulding proceb is based on machine variables which cannot compensate proceb fluctuations, a constant part quality cannot be guaranteed. The aim of the self-optimising procebing method is to compensate the effects of proceb fluctuations, to ensure a repeatable forming of the moulded part and therefore achieve a constant part quality. The so called pvT-optimisation allows, in combination with a closed-loop cavity prebure control, a systematic consideration of variable boundary conditions of the proceb. In addition, the effort required for setting up the proceb can be significantly reduced. The pvT-optimised procebing method enables the compensation of thermal disturbances and prebure fluctuations. Additionally, the influence of variations in material viscosity on the proceb variables, caused by the usage of recycled material, is addrebed. Changing temperature and prebure of the material during the proceb compensates for the variations in material viscosity. An effect analyses of the influence of viscosity-relevant proceb parameters such as melt temperature, mould temperature and injection velocity on quality criteria such as part weight is conducted. The effect analysis shows a strong correlation between injection velocity and the weight. Thus, the part weight can be controlled by adapting the injection velocity.