Prestressed Corrugated Duct Selection Guide-Comparing Plastic, Metal & Dual-Wall Solutions for Structural Applications
1. Product Types & Core Applications
A. Plastic Corrugated Duct (HDPE/PP)
- Material: High-density polyethylene (HDPE) or polypropylene (PP)
- Key Features:
- Chemical resistance (pH 2–12)
- Lightweight (0.9–1.4 g/cm³)
- Flexible installation (bending radius ≥30×OD)
- Applications:
- Electrical conduit (UL 651A)
- Drainage systems (ASTM F2648)
B. Prestressed Corrugated Metal Duct (Galvanized Steel)
- Material: Galvanized steel (G235) or aluminized steel (AZ150)
- Key Features:
- High tensile strength (≥500 MPa)
- Grout-tight spiral seams (EN 523)
- Post-tensioning compatibility (PTI M50.3)
- Applications:
- Bridge tendon ducts (AASHTO LRFD)
- Nuclear containment structures (ACI 349)
C. Dual Wall Pipe (HDPE/Steel Hybrid)
- Material: HDPE outer wall + steel reinforcement
- Key Features:
- Crush resistance (≥50 kN/m²)
- UV-stabilized outer layer
- Electromagnetic shielding (for utility tunnels)
- Applications:
- Trenchless installations (ASTM F1962)
- Oil/gas secondary containment
Dual Wall Pipe
2. Selection Criteria Comparison
| Parameter | Plastic Duct | Metal Duct | Dual Wall Pipe |
|---|---|---|---|
| Max Pressure | 0.5 MPa | 2.0 MPa | 1.6 MPa |
| Temp Range | -40°C to +60°C | -30°C to +300°C | -30°C to +80°C |
| Lifespan | 25–50 years | 50–75 years | 40–60 years |
| Cost (per meter) | 5–15 | 20–50 | 30–70 |
3. Installation & Compliance
- Plastic Ducts:
- Require sand bedding (150mm min.)
- Joints: Thermal fusion or couplers (ASTM D3212)
- Metal Ducts:
- On-site welding/bolting (AWS D1.4)
- Grout injection testing (PTI M55.1)
- Dual Wall Pipes:
- Horizontal directional drilling (HDD) compatible
- Leak detection via tracer wires (API RP 1130)
4. Industry Standards Quick Reference
- Plastic: ASTM F2160 (HDPE), ISO 9001 (QC)
- Metal: EN 523 (ducts), ACI 318 (grouting)
- Dual Wall: ASTM F2947 (polyethylene), ASME B31.3 (process piping)
