Screw flights are critical components in aggregate processing equipment, particularly in screw conveyors and classifiers used in sand/gravel production lines. Their helical design ensures efficient material transport, mixing, and size separation.
Modern screw flights for aggregate applications typically feature:
– Material: Hardox 450 or AR400 steel (3-12mm thickness)
– Diameter: 300-1500mm (matched to conveyor housing)
– Pitch: 0.5-1.5x screw diameter
– Surface treatment: Tungsten carbide overlay for abrasive resistance
| Parameter | Standard Range | Heavy-Duty Option |
|---|---|---|
| Flight Thickness | 6-8mm | 10-12mm |
| Rotational Speed | 15-45 RPM | 10-30 RPM |
| Capacity | 50-200 TPH | 300-500 TPH |
| Abrasion Life | 6,000 hrs | 10,000+ hrs |
Cold-formed flights provide better dimensional accuracy for precision classifiers, while hot-rolled flights offer superior durability for raw material handling. Advanced CNC plasma cutting ensures consistent helix geometry critical for maintaining proper material flow gradients.
1. Sand Washing: Spiral classifiers with wear-resistant flights separate fines from commercial sand
2. Feed Distribution: Variable-pitch screws ensure even material spread across vibrating screens
3. Dewatering: Steep-pitch screws remove excess moisture from crushed aggregates
Q: How often should screw flights be replaced?
A: Typically every 18-24 months under normal operation, but wear monitoring systems can extend this interval.
Q: Can existing flights be refurbished?
A: Yes, through hardfacing or complete flight segment replacement while retaining the central shaft.
Q: What’s the optimal clearance between flight and housing?
A:
