Simulation of the stretch blow molding process of PET bottles

Simulations of various stretch blow and blow moldings of axisymmetric PET bottles has been carried out using ABAQUS. A creep constitutive model with material data developed for a thermoforming process was used in the finite element analysis. Simulations using shell and solid elements were compared with experimental moldings. The creep material model, when combined with solid elements and a very high coefficient of friction, provided the best predictions for bottle side wall thickness, strains, blowing pressure, and general material movement. It was found that, using ABAQUS, the predicted wall thickness distribution of the material in an injection blow molded bottle agreed well with the values obtained using commercial process conditions.