10 Key Injection Molding Terms to Learn Now
· Cavity – The concave space in the mold, which is filled with hot plastic to create the desired part. Sometimes referred to as the “A side” or “A part” of the mold.
· Flash – Leftover plastic that goes outside of the intended part molding.
· Gate – Where the plastic enters the mold. It can be trimmed manually or automatically once the part is ejected.
· Line of Draw – The point at which the two molding halves separate to reveal the injection molded part. This allows the part to be ejected without damage from metal obstructions.
· Runner – A canal for plastic to travel from the injection molding machine, through the sprue to the gate through which the part is filled.
· Shear – The heat-inducing force created when layers of resin rub together during the injection molding process.
· Shrink Rate – Ranging from 0.001-0.060 per inch, the rate at which the injected plastic will shrink once it is cooled.
· Sprue – The canal connecting the runner to the injection molding machine nozzle.
· Vestige – Excess material protruding from the gate that can be automatically or manually trimmed by a machine operator.
· Warp – A distortion in the injection molded part, often caused by residual stresses and differential shrinkage during the cooling process.