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

As the conventional control of the injection moulding process is based on machine variables which cannot compensate process fluctuations, a constant part quality cannot be guaranteed. The aim of the self-optimising processing method is to compensate the effects of process 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 pressure control, a systematic consideration of variable boundary conditions of the process. In addition, the effort required for setting up the process can be significantly reduced.The pvT-optimised processing method enables the compensation of thermal disturbances and pressure fluctuations. Additionally, the influence of variations in material viscosity on the process variables, caused by the usage of recycled material, is addressed. Changing temperature and pressure of the material during the process compensates for the variations in material vis...