Single-Screw Plastic Pelletizing System

Single-Screw Plastic Pelletizing System

The plastic recycling pelletizing system is used in recycling plants for processing both soft and rigid plastic wastes. It handles crushed flakes and shredded materials smoothly, bringing plastic through melting and pelletizing in one continuous process. This plastic recycling line is commonly used for PE, PP, ABS, PS, PA, and PC, including regrind and plastic flakes. The finished output is uniform plastic pellets, which can be reused as raw material for film blowing, injection molding, and pipe extrusion in downstream plastic manufacturing processes.

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Recyclable Materials
  • PP rigid waste plasticPP rigid waste plastic
  • PE rigid waste plasticPE rigid waste plastic
  • PS rigid waste plasticPS rigid waste plastic
  • ABS scrapsABS scraps
  • PA rigid waste plasticPA rigid waste plastic
  • PC rigid waste plasticPC rigid waste plastic
  • PP woven bagPP woven bag
  • LDPE filmLDPE film
  • PE greenhouse filmPE greenhouse film
  • PP bulk bagPP bulk bag
  • PP woven bag (mixed color)PP woven bag (mixed color)
  • PE agricultural mulch filmPE agricultural mulch film
Video
Single-Screw Plastic Pelletizing System
Single-Stage Plastic Pelletizing System
  • High-cost efficiency as one extruder completes the full extrusion and pelletizing process. The system has a compact footprint and is suitable for plants with limited space.
  • Moisture and trapped air are released during extrusion through a single vent on the screw. The pellets come out solid and compact without visible pores.
Inquiry
Model Screw Diameter (mm) Screw Length (mm) Power (kW) Output Capacity (kg/h)
HS 110 Ø110 2600 37 150-200
HS 120 Ø120 3000 45 200-250
HS 130 Ø130 3200 55 250-300
HS 140 Ø140 4000 75 300-350
HS 150 Ø150 4200 90 350-400
HS 160 Ø160 4500 110 400-500
HS 180 Ø180 5200 160 500-700
HS 200 Ø200 6000 250 700-800
Double-Stage Plastic Pelletizing System
  • Double-Stage Plastic Pelletizing System
  • Double-Stage Plastic Pelletizing System
  • Double-Stage Plastic Pelletizing System
    • Double-Stage Plastic Pelletizing System
    • Improved melting and plasticizing.
    • The screw design includes two venting sections, which results in higher efficiency for larger-throughput production.
    • The system can handle a broad range of plastics, including PE, PP, PA, PS, PC, and ABS.
    Inquiry
    Model Screw Diameter (mm) Screw Length (mm) Power (kW) Output Capacity (kg/h)
    HS 110/110 Ø110 2600 37 200-250
    Ø110 1100 11
    HS 120/120 Ø120 3000 45 250-300
    Ø120 1200 15
    HS 130/130 Ø130 3200 55 300-350
    Ø130 1300 18.5
    HS 140/140 Ø140 4000 75 350-400
    Ø140 1400 30
    HS 150/150 Ø150 4200 90 400-500
    Ø150 1500 37
    HS 160/160 Ø160 4500 110 500-600
    Ø160 1600 37
    HS 180/180 Ø180 5200 160 700-900
    Ø180 2000 45
    HS 200/200 Ø200 6000 250 900-1000
    Ø200 2600 75
    Video
    Triple-Stage Plastic Pelletizing System
  • Triple-Stage Plastic Pelletizing System
  • Triple-Stage Plastic Pelletizing System
  • Triple-Stage Plastic Pelletizing System
    • Triple-Stage Plastic Pelletizing System

    In addition to the advantages of single-stage and double-stage systems, the triple stage palletizer is used for tighter control over pellet quality. It is mainly used in plastic film and other soft-material processing.

    Inquiry
    Model Screw Diameter (mm) Screw Length (mm) Power (kW) Output Capacity (kg/h)
    HS 110/110/110 Ø110 2600 37 200-250
    Ø110 1100 11
    Ø110 1100 11
    HS 120/120/120 Ø120 3000 45 300-350
    Ø120 1200 15
    Ø120 1200 15
    HS 130/130/130 Ø130 3200 55 350-400
    Ø130 1300 18.5
    Ø130 1300 18.5
    HS 140/140/140 Ø140 4000 75 400-450
    Ø140 1400 30
    Ø140 1400 30
    HS 150/150/150 Ø150 4200 90 450-500
    Ø150 1500 37
    Ø150 1500 37
    HS 160/160/160 Ø160 4500 110 500-600
    Ø160 1600 37
    Ø160 1600 37
    HS180/180/180 Ø180 5200 160 700-900
    Ø180 2000 45
    Ø180 2000 45
    HS 200/200/200 Ø200 6000 250 900-1000
    Ø200 2600 75
    Ø200 2600 75
    System Composition and Operating Process
    Step 1

    Material Feeding & Conveying
    After crushing and washing, the material is transferred to the extruder by a conveyor belt. Once it enters the screw, compression and melting begin. Moisture and trapped gases are released along the way. The melt is passed through the filtration system before pelletizing. Feeding speed is adjusted based on how the line is actually running, rather than fixed settings. Depending on line size, conveyor motor power usually falls between 0.4 kW and 3 kW. The conveyor belt is made from PVC or rubber, chosen for wear resistance and long service life. A magnetic roller at the top section catches metal fragments before they reach the extruder.

    • Rigid plastic conveyingRigid plastic conveying
    • Flexible plastic conveyingFlexible plastic conveying
    Step 2

    Volumetric Feeding

    • Rigid material feederRigid material feeder
    • Flexible material feederFlexible material feeder
    Step 3

    Single-Screw Extrusion

    • Variable-frequency control is used so feeding speed adjusts with extrusion load, allowing a stable feeding speed that follow the actual output requirement.
    • A photoelectric sensor monitors material flow and manages automatic feeding control.
    • The barrel uses a longer L/D ratio. A single-stage extruder can be configured to run as a double-stage setup.
    • The screw is made from high-strength 38CrMoAl alloy steel, heat-treated for long-term stability.
    • Single-Screw Extrusion
    Step 4

    Filtration System

    Self-Cleaning Melt Filter
    Self-Cleaning Melt Filter (Optional for double-stage plastic palletizing line)

    The self-cleaning melt filter operates while the extruder is running. Contaminants are removed automatically from the filter surface without interrupting the production. It reduces manual cleaning and maintenance work, and is suitable for recycling materials with higher levels of contamination.

    Double Plate Screen Changer
    Double Plate Screen Changer (Screen change without stopping the line)

    This filter uses two screen plates that work alternately. When one screen is being changed, the other remains in operation, allowing filtration to continue without interruption. Heating elements are built into the unit to keep temperature consistent during screen changes. In double-stage single-screw lines, a piston-type screen changer can also be used as an alternative option.

    Step 5

    Cooling & Pelletizing
    After extrusion, the molten plastic strands pass through a cooling water trough, where they are solidified quickly. The cooled strands are then pulled forward and fed into the pelletizer. The rotating cutter in the pelletizer slices them into pellets of consistent length.

    • Strand PelletizerStrand Pelletizer
    • Strand PelletizerStrand Pelletizer
    Step 6

    Screening
    The vibrating screen is made from stainless steel to resist corrosion during long-term operation. As pellets pass through, screening, conveying, and cooling take place at the same time. Qualified pellets move forward, while oversized pieces and fine powder are separated out for consistent pellet sizes.

    • Vibrating ScreenVibrating Screen
    • Vibrating ScreenVibrating Screen
    Step 7

    Packaging & Storage
    Qualified pellets are collected, packaged, and moved into storage.
    Our factory has over 30 sets of CNC lathes in the production of plastic processing equipment, such as feeding sawing machine, CNC gantry machining center, CNC screw milling machine, CNC deep-hole boring machine, and cylindrical grinder. Meanwhile, with the adoption of more technologies into plastic recycling, CAD/CAM continues to grow in importance. Thus during the whole manufacturing process, our experienced engineers and technicians utilize CAD/CAM engineering approaches to optimize the entire operation. This allows us to supply high quality plastic machinery with optimal performance.

    Melting and pressure-building are handled separately in double-stage pelletizing line. The second stage of pelletizing performs melt stabilization, degassing, and filtration. This improves material consistency and removes impurities commonly found in ABS and PS regrind.

    The main difference between the pelletizing lines depends on how the screw units are arranged and divided. A single-stage line completes the entire process with one screw, while double-stage and triple-stage lines separate melting, degassing, and pressure control into different sections. These configurations are selected based on material behavior and process needs, rather than performance ranking.

    Using a double-stage pelletizing line combined with efficient filtration, recyclers can produce clean, stable pellets that meet the forming requirements for agricultural planting pots.