There are different reasons to eject the material from the injection cylinder in front of the mold.
This is done during the start of a machine, after a long residence time in the cylinder or if a change of the material is needed.
If purging compound is used, it will not go into the mold but is collected right after the machine nozzle.
A cylindrical strand of melt emerges from the machine nozzle. The melt accumulates in any form in front of the nozzle.
This form is called the melt ejection.
After the melt is cooled down the melt ejection will be removed from the machine.
Due to it’s irregular shape and it’s weight the melt ejection will not be recycled but thrown away.

Melt ejection in Plastic Industry

Plastic: Melt ejection in front of the machine nozzle.

Melt ejection in Plastic Industry

Plastic: Melt ejection after it is removed from the machine.

Related topics:

Degeneration

This glossary of plastic industry is provided by PLEXPERT Canada Inc.