Engineering Insights
Mold Venting: What to Vent and Where
Venting removes cavity air and material gases. Its location must follow filling ends, flow convergence, and sealing conditions.
Why venting matters
Trapped gas can cause burns, short shots, weak weld lines, high local pressure, and unstable dimensions.
Where to place vents
Focus on final-fill areas, weld regions, deep rib ends, enclosed geometry, and locations that seal early during filling.
Common methods
Parting-line vents, insert clearances, ejector clearances, and dedicated structures can be used. Vent depth must balance gas release with flash prevention.