I. Single-Screw Feeder

Applicable Materials:

1. Free-flowing powders & granules: Such as PVC pellets, urea, quartz sand, and food additives (acidity regulators, preservatives) .
2. Recycled/irregular granules: Suitable for uneven-sized recycled materials .

Features:

• Simple structure: Low-cost design, easy maintenance, ideal for low-precision applications .
• Flexibility: Speed adjustable via frequency conversion (1-500 kg/h) .
• Limitations: Struggles with sticky, bridging-prone, or fibrous materials (e.g., pigments, glass fibers) due to friction or clogging .

II. Twin-Screw Feeder

Applicable Materials:

1. Challenging materials:
   • Viscous substances (e.g., masterbatches, high-pigment concentrates) .
   • Bridging-prone powders or fibers (e.g., flour additives, fibrous materials) .
   • Glass fiber-reinforced or flake materials: Improves flow via screw shear .
2. Mixing requirements: Intermeshing screws enable preliminary mixing for colorants or multi-component formulations .

Features:

• High precision: Equipped with loss-in-weight systems (±0.25%–±1% accuracy) .
• Anti-bridging design: Horizontal/vertical agitators prevent material buildup .
• Modularity: Easy disassembly for cleaning and material changes .

III. Selection Guidelines

1. Choose single-screw when:

   • Handling free-flowing materials without mixing needs.
   • Budget-constrained or precision requirements are moderate .

2. Choose twin-screw when:

   • Processing viscous, fibrous, or bridging-prone materials.
   • High-precision dosing or mixing is required (e.g., multi-component systems) .

IV. Key Technical Insights

• Twin-screw advantages: Higher throughput (1.5–2× single-screw) and better mixing .
• Material compatibility: Stainless steel (304/316L) contact parts for corrosion resistance .
• Extended applications: Even for free-flowing materials, twin-screw is preferred if precision or mixing is critical .