Pelletizing is the step at the end of an extrusion line that cuts molten plastic into small, uniform granules, also called pellets. It is the point where recycled plastic becomes a standard raw material that converters can store, dose and process.
There are three common methods. In strand pelletizing, spaghetti-like strands are cooled in a water bath and chopped. In water-ring, or die-face, pelletizing, rotating knives cut the melt at the die and a ring of water cools the pellets. In underwater pelletizing, cutting happens fully submerged, giving very round, even pellets. After cutting, pellets are dried, screened for size and packed. Uniform pellets flow and melt evenly, which is what makes recycled granules a drop-in replacement for virgin plastic granules.
