Underwater Pelletizer

The underwater pelletizing system consits of a polymer diverter valve, a pelletizing unit, a water treatment and drying system and an electrical control system.

● When started, the melt flow is directed downwards by the polymer diverter valve. Once a constant melt flow is given, the stream is redirected and the die plate is rinsed with melt.

● As soon as the melt is continuously emerging from each hole, the stream is once again directed downwards. The die plate is cleaned and the pelletizer housing is fixed to the pelletizing head by means of the hydraulic lock.

● Afterwards, the melt is directed to the pelletizing head with the die plate installed, and the emerging melt strands are pelletized under water. The pellets are then moved to the water treatment and drying system by the process water. The separator then removes any potential lumps.

● In the pre-dewatering unit, the pellets are separated from the process water and conveyed to the centrifugal dryer. The centrifugal forces in the dryer and the special arrangement of the blades propel the pellets upwards and simultaneously separate the residual water via screens.

● The pellets exit the system at top and move on to the next step.

● The process water is collected in the water tank, filtered and recirculated to the process. A cooling circuit with plate heat exchanger is integrated to control the process water temperature.

Cowin has the original R&D team of under water pelletizing system in China. We focus on the latest technology innovation which helps our UW series to be high quality and more competitive.

● Full automatic pneumatic knife feeding system to guarantee stable and continuous production. Cutting blade which contacts the die head can be adjusted automatically after abrasion, thus to guarantee the precise contact between cutter and die head. With PLC controlling system to meet manual/automatic operation, touch screen makes the operation and maintenance easily.

● Super anti-wear hard alloy cutting blade with constant pneumatic cutting adjusting system to guarantee a longer life span.

● Modular Designed Tempered Water Circulating System to meet different requirement from customers. Every part can be installed independently which makes it easier and faster to replace.

● Based on requirements of customers as well as the characteristic of raw materials. COWIN EXTRUSION super anti-wear hard alloy die plate, cutting blades, high efficient and low energy consumption heading system make the cutting result more perfect.

Typical application areas are:  

● Polyolefins, e.g., LDPE, HDPE, PP

● Styrene polymers, e.g., PS, SAN, ABS

● Acrylic resins, e.g., PMMA, PAN

● Polyacetals, e.g., POM

● Polycarbonates, e.g., PC

● Polyesters, e.g., PET, PBT, PEN

● Polyamides, e.g., PA 6, PA 66, PA 11, PA 12

● Thermoplastic elastomers, e.g., TPE-S, TPE-E

● Polyurethanes, e.g., TPU

● Hot-melt adhesives

● Rubber

● Natural and synthetic resins

● Biopolymers, e.g. PLA, PHA, Bio-PA, Bio-PET, Bio-PP