Underwater Pelletizing Systems - High Efficiency & Superior Pellet Quality
USEON's Underwater Pelletizing System is an advanced granulation solution in which thermoplastic materials are melted and cut directly in water to form uniform pellets.
This technology offers high throughput rates, tight pellet size tolerances, a wide application range, and a high level of automation. It is particularly ideal for TPU, TPV, elastomers, and micro-pellet production.
What is Underwater Pelletizing?
Underwater pelletizing operates by transferring molten polymer through a die plate into a water-filled cutting chamber.
The material is instantly cut by high-speed rotating knives under water and simultaneously cooled. The resulting pellets are transported by water flow, separated, and then directed to a drying system.
This synchronized cutting and cooling process ensures dimensional stability and consistent pellet geometry.
System Components & Production Flow
A typical USEON underwater pelletizing line includes the following main components:
Melt Pump + Filtration Unit
Ensures stable melt pressure and consistent material flow.
Diverter Valve
Directs the melt stream toward the pelletizer.
Die Head & Underwater Pelletizer
The cutting and pellet forming unit, consisting of multi-hole die plates and precision cutting knives.
Water Circulation System
Provides continuous cooling and controlled cutting environment.
Dewatering & Drying System
Separates pellets from process water and ensures low residual moisture.
Control & Automation Panel
Monitors and optimizes all key process parameters for stable production.
All components operate in an integrated engineering structure, delivering high product quality and excellent production stability.
Advantages - Performance & Production Efficiency
1. Micro-Pellet Production (≤ 1 mm)
Underwater pelletizing enables micro-pellet production that is difficult to achieve with conventional strand systems.
Benefits of micro-pellets include:
• More homogeneous distribution of solid additives such as masterbatch
• Reduced dosage of colorants and functional additives
• Lower overall formulation cost
• Dust-free pellets with excellent flowability
2. Exceptional High Capacity
Conventional pelletizing systems often struggle to maintain efficiency above 1,000 kg/h.
USEON underwater pelletizing systems can achieve production capacities of up to 50 tons per hour.
This wide capacity range makes the system ideal for petrochemical plants and large-scale industrial extrusion lines.
3. Processing of Soft & Elastomeric Materials
Low-hardness materials such as TPE, TPV, EVA, and compounds below Shore A < 40 can be processed reliably using underwater pelletizing technology.
The immediate water cooling prevents sticking, deformation, and strand breakage typically encountered in conventional pelletizing systems.
Technical Capacity Examples
Below is an overview of USEON model ranges and typical output capacities:
Model | Diverter | Hole No. | Knife No. | Output
UWP300 | D30 | 8-10 | 4-6 | 50-300 kg/h
UWP500 | D40 | 20-30 | 6-8 | 200-700 kg/h
UWP1000 | D50 | 40-80 | 8-12 | up to 2 ton/h
UWP2000 | D60 | 100-160 | 10-16 | 2-6 ton/h
UWP4000 | D60 | 100-160 | 12-18 | 3-8 ton/h
These ranges can be further optimized depending on material type, formulation, and overall line configuration.
For example:
• TPU micro-pellet production line: 30 kg/h output
• PS micro-pellet line: pellet diameter of 0.8 mm
Product Quality & Technical Features
Pellets produced by underwater pelletizing systems offer:
• Uniform and spherical pellet shape
• Narrow dimensional tolerances
• Low dust generation
• High bulk density and excellent flow characteristics
• Closed-loop water circulation for reduced operating costs
• Full automation and precise process control
These characteristics significantly improve performance in masterbatch production, TPU/TPV compounding, elastomer granules, and micro-pellet applications.
Application Areas
Underwater pelletizing technology is widely used in:
• Industrial plastic granule production
• Elastomeric compounds and TPE manufacturing
• Masterbatch and additive masterbatch production
• Polymer recycling
• Engineering plastics production
• Bioplastics and PET applications
• High-performance specialty polymers
USEON underwater pelletizing systems combine high capacity, superior pellet quality, and broad material compatibility, making them one of the most strategic components of modern extrusion and pellet production lines.
With underwater pelletizing, manufacturers achieve:
• Reduced material waste
• Lower operating costs
• Higher production efficiency
• Consistent pellet quality in both micro and standard sizes
Underwater pelletizing is not just a cutting method - it is a high-precision granulation solution designed for demanding industrial production environments.
