Push-pull-processing (PPP) is a live in-mold manipulation method of co-injection molding providing increased opportunities for controlling the melt flow during solidification. The mold has two gates connected to two synchronized injection units. During the packing phase, the melt moves through the mold several times. This modified filling process influences the orientation of fibers in a part significantly. In this work, a modified 3-D model for PPP has been developed and performed with the aid of a commercial software package (Moldflow) in order to predict the fiber orientation distribution within the weldline area of PPP parts. The predicted values of orientation tensor components (a11) are found to agree reasonably well with corresponding experimental measurements.
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