A weakness or visible flaw created when two or more flow paths meet and converge while filling a plastic part.
Meld lines can be caused by holes or inserts in the part, multiple injection gates, or variable wall thickness where hesitation or race tracking can occur.
Parallel flows typically form a meld line. Flows meeting at higher angles, often head on, form Weld lines.
Note: The Weld and meld lines result in the Study Tasks pane do not always show meld lines if the model mesh is too coarse.
Meld lines tend to be less weak than weld lines. The material type, the type and number of fillers, and the pressure and temperature at the meld line affect the quality of the meld line.
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