The thermoplastic melt goes through die bores, arranged in a circle and will be directly cut by rotating blades running on the die surface. In contrast to the waterring pelletizing system the complete pelletizing chamber of the underwater pelletizing system is filled up with water - that means the cut is "under water". The pellets are cooled down in the water and in cause of the high flow rate they will be transported directly in the centrifugal dryer. There the pellets will be separated from the water and dried - the process water flows back into the watertank. After cooling down inside the heat exchanger the water will be pumped back into the pelletizing head.
A starting automatic will save, that in the starting procedure melt and water flows exactly at the same time, which prevents smeared blades and frozen die bores.