Experimental validation of shrinkage predictions for injection molded products

Two injection moulding simulation codes (C-MOLD of AC Technology and VIp of Eindhoven University) are compared with experimental results regarding cavity pressure and product shrinkage. It turns out that the cavity pressure profiles are only moderately well predicted by both codes. The shrinkage predictions can be considered as a post processing step with temperature and pressure fields as an input (the so-called thermoelastic model). It is shown that the shrinkage predictions agree well with the measurements using the thermoelastic model with actual pressure profiles as an input. Direct simulation of product shrinkages resulted in an overprediction of shrinkage.