Underwater Pelletizer (UWP)

The Underwater Pelletizer (UWP) represents a revolution in the field of polymer material granulation. It combines the extrusion of molten polymer with precise temperature controlled circulating water to achieve instant granulation and synchronous solidification. This system is designed specifically for high-yield, automated plastic modification and recycling production lines, and is an ideal choice for pursuing dust-free and perfect spherical particles.

·Closed loop circulating water system: The fully enclosed water circuit design ensures uniform distribution of water temperature, allowing the melt to achieve rapid and consistent cooling and shaping after cutting.
·Hydraulic mold surface detachment device: using a servo controlled hydraulic mechanism, it can quickly and automatically move away the mold surface for easy cleaning, significantly reducing downtime during material switching.
·High speed synchronous cutter assembly: The precision machined cutter assembly synchronizes with the extrusion speed in real-time, ensuring high uniformity of particle size even under high production capacity conditions.
·Wear resistant alloy components: The mold head and cutting blade are made of high-quality alloy steel and wear-resistant coating treatment, which maintains a long service life even when processing high filling materials.

Noted: Details depend on your requirements and need.

Why choose underwater cutting system instead of traditional strip cutting or air-cooled cutting?
·Better particle morphology: The edges of cylindrical particles obtained by traditional strip cutting are prone to burrs and powder, while UWP can generate perfect spherical particles with uniform and dust-free particles, greatly improving the packing density and avoiding dust problems during pneumatic conveying.
·Efficient and energy-saving: The entire plastic granulation process is completed in a closed environment, without the need for long-distance cooling conveyor belts. Compared to traditional water tank stretching lines, it occupies about 30% less space.
·Adapting to high temperature and high viscosity materials: For high viscosity or high melting temperature polymers, traditional water ring cutting can easily cause particle deformation. UWP instantly fixes the particle shape by immersing the melt in water as soon as it exits the mold, ensuring product quality.

Our UWP Underwater Pelletizer is widely used in the following plastic granulation scenarios:
·Modified plastics industry: high filling masterbatch (calcium carbonate, talc powder), fiberglass reinforced PP/PA, colored masterbatch.
·Recycling industry: post consumer hard plastics (HDPE, PP), film recycling (LDPE, LLDPE), electronic and electrical waste recycling.
·Special materials: hot melt adhesive, elastomers (TPU, TPE), biodegradable plastics (PLA, PBAT).
·Chemical fiber industry: Production of polyester chips.

Nanjing Kelongwell Chemical Machinery Co., Ltd. is well aware that each production line has unique requirements. We provide comprehensive OEM/ODM customization services:
·Customized design of mold heads: Based on the rheological properties of the material, optimize the number, arrangement, and heating zones of the mold faces.
·Whole line integration: can seamlessly integrate with your existing twin-screw extruder or upstream feeding system.
·Wear resistant reinforced coating: For highly abrasive materials, tungsten carbide or diamond-like carbon coatings are provided to maximize the lifespan of critical components.
·Automation solution: The PLC control system can choose between semi-automatic or fully automatic Industry 4.0 interconnection solutions according to requirements.

Q1: What are the main differences between underwater pelletizing systems (UWP) and traditional strip pelletizing systems?
A: The core difference lies in the sequence of cooling and cutting. Strip cutting is the process of first extruding a strip of material, cooling it in a water tank, and then cutting the particles into cylindrical shapes, which require a lot of manual operation. And our UWP cuts directly in the water chamber as soon as the melt exits the mold, and the particles are immediately cooled by the water flow to form a perfect spherical shape, while achieving fully automated operation. Compared with traditional stretching lines, labor costs can be reduced by about 50%, and there is no need for manual stretching, greatly improving efficiency.

Q2: Can this underwater cutting system process high filling materials, such as 80% calcium carbonate masterbatch?
A: Sure. We have designed reinforcement specifically for high filling and high abrasion applications. The mold head and cutting blade are made of high wear in steel, and special coatings are provided through OEM customization options. At the same time, the hydraulic mold surface detachment device facilitates quick cleaning of the mold surface, ensuring that the plastic granulation process remains stable and continuous under harsh working conditions.

Q3: Is UWP suitable for both recycling material granulation and new material modification?
A: Yes. Our underwater pelletizing system has a wide range of material adaptability. For recycled materials, the cutting blade component can withstand fluctuations caused by impurities in the melt; For new material modification, a precise temperature control system can ensure that the material quality is not affected. Therefore, UWP is the true solution for achieving "one machine, multiple uses" in plastic granulation lines.

Q4: Compared to air-cooled pelletizing systems, how does the energy consumption performance of underwater pelletizing systems compare?
A: Although UWP uses a water cycle, its overall energy consumption is often lower. Air cooled pellet cutting requires long-distance cooling of conveyor belts and multiple fans, which occupies a large area and has limited heat dissipation efficiency. Our closed-loop water system uses efficient water pumps and heat exchangers, which significantly reduce the specific energy consumption per unit capacity. At the same time, the particle cooling is uniform and the post-treatment is simpler.

Q5: How automated is the system? What are the security guarantees?
A: We provide an integrated PLC control system that can achieve automatic startup process, mold head pressure monitoring and emergency shutdown interlocking, automatic water temperature adjustment, etc. The hydraulic die surface is disengaged and interlocked with the cutter motor and extrusion pressure to ensure safe operation. Operators only need to manage the entire plastic granulation line through the central human-machine interface, greatly reducing manual intervention and improving production safety.