Ring Die Pelleting Machine

The ring die pelleting machine is a high-efficiency device that uses a ring die and pressure rollers to extrude powdered materials into cylindrical pellets. The ring die has a vertically installed ring structure, and the pressure rollers rotate and crush the material inside the die, extruding it from the inside out. This design makes the ring die pelleting machine superior in terms of production capacity, pellet density, and continuous operation stability, making it particularly suitable for medium to large-scale feed processing and organic fertilizer production. The equipment features mature technology, a high degree of automation, and a wide range of single-machine capacity, making it one of the main models in the pellet feed industry and large-scale organic fertilizer processing. The ring die pelleting machine is highly adaptable to different materials and performs stably even when processing organic fertilizer raw materials with high fiber content, making it an important equipment choice for pelleting in the feed and fertilizer industries.

Working Principle for Ring Die Pelleting Machine

The material is forcibly fed into the granulation chamber by a screw feeder. The granulation chamber contains a vertically installed ring die, and the inner cavity of the ring die has two to three pressure rollers. Driven by the main motor, the ring die rotates at a uniform speed. Material entering the ring die cavity is distributed between the pressure roller and the inner wall of the ring die. As the ring die rotates, the pressure roller passively rotates under friction, crushing and forcibly squeezing the material into the densely packed die holes on the ring die wall. The material undergoes compression and shaping within the die holes, and is continuously extruded from the outer wall of the ring die in a cylindrical strip shape. An adjustable cutter is installed on the outside of the ring die to cut the extruded strip material to a set length, forming uniform cylindrical granules. The entire granulation process is completed at room temperature through pure mechanical extrusion, with limited material temperature rise. No external binder or steam heating is required, resulting in dense, uniformly sized granules.

Structural Components for Ring Die Pelleting Machine

Ring Die: A ring-shaped die forged from high-quality alloy steel; its surface undergoes heat treatment to ensure high hardness and strong wear resistance. The die wall features precision-machined holes—with diameters ranging from 2mm to 12mm—that determine the size of the finished pellets. The ring die is a wear part and can be replaced once it reaches the end of its service life.

Roller Assembly: Two or three rollers are mounted on an eccentric shaft within the ring die’s inner cavity; their surfaces feature a toothed pattern to enhance material grip. Supported by bearings, the rollers rotate passively as the ring die turns, maintaining a slight clearance from the inner die wall while crushing and forcing material into the die holes.

Drive System: The main motor connects to a gearbox via belts or a coupling, with the gearbox output shaft driving the rotation of the ring die. The system features a compact design, high torque transmission efficiency, and smooth operation, making it suitable for continuous, heavy-duty conditions.

Feeding and Conditioning Unit: A screw feeder is positioned above the inlet, with feed rates controlled by a variable-frequency drive (VFD). Some models include a conditioner between the feeder and the granulation chamber, allowing for the addition of small amounts of water or steam to pre-treat the material and improve pellet quality.

Cutter Assembly: Adjustable cutters are mounted on the exterior of the ring die; the assembly typically features two to four blades, with the gap between the blade and the die surface being adjustable. The cutters sever the extruded material to a set length, ensuring uniform and controllable pellet size.

Frame and Guarding: The frame is constructed from welded steel plate, offering high structural rigidity. A protective guard encloses the granulation chamber to ensure operational safety while facilitating cleaning and maintenance.

Performance Characteristics

Large Production Capacity: The ring die structure forces material to be extruded from the inside out, resulting in a large effective working area and significantly higher single-machine capacity than flat die pelleting machines of the same specifications. Suitable for continuous operation in medium to large-scale production lines.

Dense and Uniform Particles: The material undergoes strong compression between the ring die and the pressure rollers, and is fully compressed and shaped after being squeezed into the die holes. This results in high-density, high-strength particles that are not easily broken or pulverized, offering excellent storage and transportation performance.

High Die Utilization: The inner wall of the ring die is covered with die holes, providing a large working surface and relatively uniform wear. The lifespan of a single die is long, resulting in good overall economic efficiency in terms of both production capacity and die life.

Wide Material Adaptability: It can process both fine materials such as compound feed and concentrated feed, as well as coarse materials such as fermented organic fertilizer with high fiber content and straw powder, making it widely applicable.

Stable and Reliable Operation: The transmission system is maturely designed, with high precision in the fit between the ring die and the pressure roller. The equipment operates with low vibration and noise, making it suitable for long-term continuous production.

Convenient Operation and Maintenance: Dedicated tools and operating windows are provided for ring die replacement and pressure roller disassembly, facilitating maintenance. The equipment has a high degree of automation and can be integrated into a central control system for the entire production line.

Application Fields for Ring Die Pelleting Machine

Feed Industry: Core equipment for pelleting compound feed, concentrated feed, aquatic feed, and pet food.

Organic Fertilizer Processing: Pelletizing fermented chicken, pig, sheep, and cow manure; granulating agricultural waste such as straw powder and rice husk powder.

Bio-Organic Fertilizer: Granulating bio-organic fertilizer with added functional microbial agents at room temperature, preserving the activity of the microbial agents.

Biomass Fuel: Pelletizing biomass powders such as sawdust, straw, and peanut shells for use in the biomass energy sector.

Chemical Industry: Extrusion granulation of certain chemical powders, additives, and auxiliaries.