Single Screw Pelletizer For PET Plastic Flakes

Working principle

1. Feeding and Removing Moisture. The motor drives the conveyor belt and hauling device with automated controlled feeding speed. A metal detector can be added to the belt conveyor and can be integrated with the control system to warn and stop the system.The compactor removes moisture from the PET flakes by high speed rotary and friction. This is very important as high moisture content of the material will lower the IV.

2. Single Screw Extruder. The PET material is moved forward by the screw’s rotation and at the same time completes the compacting, melting, and homogenization process. The screw is made of high quality nitride steel (38CrMoAlA) and processed with nitride treatment to increase it’s ability of corrosion resistance and wear-resisting.

3. Barrel. The barrel is part of screw pair and is made of nitride steel where the inner surface is treated with nitride to increase surface hardness and improve wear resistance. The energy generated by heaters transmits through the barrel to the melt the plastic. There are temperature sensors and cooling fans assembled within each heating zone.

4. Vacuum Degassing. Its function is to remove low molecular weight materials and any remaining moisture from the melted PET plastic.The vacuum degassing system consists of vacuum pump, vacuum room, filtering tank, pressure gauge and pipelines. It makes use of a water ring vacuum pump which forms high negative pressure by water sealing and is therefore suitable for removing waste gas and water.

5. Plasticizing And Degassing. A specialized single-screw extruder gently melts the PET plastic material. During the melting and plasticizing process, a double-zone vacuum degassing system efficiently removes volatiles such as low molecular weight materials and moisture.

6. Melt Filtration. A single-plate / piston double-station or non-stop double-plate / piston four-station screen changer can be installed on head of extruder to present significant filtration performance. The requirements on the filter technology depends heavily on the quality of the input material as well as the application of pellets.

7. Pelletizing. Underwater pelletizing system is the standard granulating method for PET flakes. Our system has a self-adjusting pelletizing head resulting in the best granulate quality possible.

8. Vibration Dry And Bagging Station. Advanced vibration sieve combined with a horizontal centrifugal dryer offers high-performance dried pellets at low energy consumption. The final bagging station can be built as per the height of the PP jumbo bags you use.

Product Parameter