High-Consistency Pelletizing for Polymer and Elastomer Compounding
The underwater pelletizing line is designed for applications that require uniform pellet shape, controlled pellet size, efficient cooling, and compact line layout. It is commonly used for low-viscosity polymers, TPU, TPV, elastomers, and other polymer compounds where pellet consistency is important.
In underwater pelletizing, the material is cut directly in water at the die face. The pellets are cooled immediately and transported through the water circulation system to dewatering and classification equipment. This fast cooling and controlled cutting process helps produce pellets with stable size and good appearance.
This system is especially useful for high-output production lines where compact layout and consistent pellet quality are required. It can also be used for selected PA and PC applications when pellet consistency is a critical requirement.
How the System Works
After the polymer melt exits the extruder, it passes through the underwater pelletizing die. The cutting blades rotate directly against the die face, cutting the melt into pellets inside the water chamber.
The water immediately cools the pellets and carries them through the circulation pipeline. The pellet-water mixture then enters the dewatering system, where water is separated from the pellets. After dewatering, the pellets are classified and transferred to the product silo or downstream handling system.
According to project requirements, the line can also be connected with automatic packaging systems or other downstream equipment.
Main Components
The underwater pelletizing line typically includes:
- Underwater pelletizing die head
- Underwater pelletizer
- Cutting chamber
- Water circulation system
- Heat exchanger or water temperature control system
- Dewatering system
- Vibrating classifier
- Product silo
- Optional automatic packaging connection
Suitable Materials and Applications
This system is commonly used for:
- TPU compounds
- TPV compounds
- Low-viscosity polymer compounds
- Elastomer materials
- Modified polymer compounds
- Selected PA and PC applications requiring consistent pellet quality
- High-output compounding lines requiring compact layout
- General polymer compounding applications suitable for underwater pelletizing
Key Advantages
- Excellent pellet size control
- Uniform pellet shape and stable quality
- Compact layout for high-output production
- Fast and efficient pellet cooling
- Suitable for TPU, TPV, elastomers, and low-viscosity polymers
- Can be used for selected PA and PC applications
- Can be integrated with downstream handling or automatic packaging systems
Controlled Pellet Quality for Demanding Applications
For TPU, TPV, elastomers, and other materials requiring precise pellet formation, underwater pelletizing delivers fast cooling and consistent cutting in a compact production layout. The system can be engineered around the polymer’s viscosity, die pressure, pellet size specification, water temperature control, and downstream transfer or packaging requirements.
