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GeoStruct™ Structured Wall HDPE Pipe (KN4 / KN8) | Spiral Corrugated Drainage Pipe South Africa
GeoStruct™ Structured Wall HDPE Pipe (Spiral KN4 / KN8)
GeoStruct™ Structured Wall HDPE Pipe is a spiral-profile engineered thermoplastic pipe system designed for gravity and non-pressure applications including stormwater, sewer, drainage, culverts, and infrastructure networks.
GeoStruct™ Structured wall HDPE pipe is produced through a profile extrusion process where a rectangular profile is spirally wound and fused into a continuous pipe with smooth internal bore and structural external profile.
This manufacturing method combines:
structural strength
low weight
hydraulic efficiency
into a single engineered pipeline solution.
Applicable Standards
GeoStruct™ pipes can be supplied in compliance with:
SANS 21138 — Structured Wall Thermoplastic Pipes
SANS 10268-1 — HDPE Welding Procedures
SANS-approved HDPE raw materials
Manufacturer testing includes melt flow, thermal stability, carbon black dispersion, tensile analysis and pressure testing.
Dimensional Range
GeoStruct™ Structured wall HDPE pipe systems are specified by:
Inside Diameter
Ring Stiffness Class
Available range:
| Parameter | Range |
|---|---|
| Internal Diameter | 300 – 1500 mm |
| Stiffness Classes | SN4 / SN8 |
| Pipe Type | Structured Wall |
| Application | Gravity / Non-pressure |
GeoStruct™ Structured wall pipe sizes from 300mm to 1500mm with stiffness of 4kN/m² or 8kN/m² are standard production capability
Jointing Systems
GeoStruct™ systems can be supplied with multiple jointing methods depending on project requirements:
Mechanical Coupling + Rubber Seal
Sand-tight or water-tight configuration
Resistant to stormwater and sewer effluent
Installed by alignment, cleaning, lubrication and push-fit assembly
Extrusion Welded Joints
Fully welded joint system
Leak-free performance
Suitable for dolomite ground conditions
Compliant with SANS welding standard
Sleeve & Clamp Joint Systems
Used for:
maintenance
repair
gravity drainage systems
Typical Engineering Applications
GeoStruct™ Structured wall HDPE pipe systems are commonly used for:
Stormwater drainage networks
Sewer pipelines
Culverts
Municipal infrastructure
Road drainage systems
Marine outfalls
Industrial drainage
Mine water management
Structured wall pipe is increasingly replacing concrete, corrugated metal pipe and PVC in gravity applications
Hydraulic Design Characteristics
GeoStruct™ Structured wall HDPE pipes have low internal friction.
Typical Manning roughness coefficient:
n = 0.01
Product Range: Spiral Structured Wall (KN4 / KN8)
GeoStruct™ Spiral is available in the following nominal diameters:
300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1500mm
Ring stiffness classes: KN4 and KN8
GeoStruct™ Structured Wall Pipe — Key Specs
Type: Spiral Structured Wall HDPE Drainage Pipe
Classes: KN4 | KN8 (Ring Stiffness)
Diameter Range: 300–1500 mm
Standard Lengths: Project-specific supply
Material: HDPE Structured Wall Profile
Application: Gravity drainage & stormwater systems
Key Performance
Lightweight – fast installation
Corrosion & chemical resistant
High flow capacity (smooth bore)
Flexible yet structurally strong
Long service life
Typical Uses
Stormwater drainage
Culverts
Mine drainage
Industrial runoff lines
Agricultural drainage
Installation Compatibility
✔ Trench installation
✔ Bedding class systems
✔ Road crossings (KN8)
✔ Deep burial conditions
Supply Options
• Supply only
• Supply + delivery
• Supply + installation support
Mechanical & Material Properties
GeoStruct™ HDPE properties:
Density: 0.93 – 0.97 g/cm³
High strength-to-density ratio
Continuous service temperature ≈110 °C
Short-term temperature ≈120 °C
Excellent chemical resistance
HDPE material characteristics allow use for potable water, chemical effluent and industrial applications.
Structural Advantages vs Conventional Materials
Compared to traditional drainage materials:
Up to 90% lighter than concrete pipe
5× more abrasion resistant than concrete
Excellent chemical resistance
Up to 100-year service life
These characteristics significantly reduce installation cost, transport cost, and structural loading
Handling & Installation Guidance
Recommended handling practices:
Small pipes may be handled manually
Larger diameters require lifting equipment
Lifting straps must be used — not chains
Pipes must never be dropped
Larger pipes should be loaded first during transport
System Performance
GeoStruct™ Structured wall HDPE systems provide:
leak-free joints
corrosion resistance
root intrusion resistance
reduced joint count
long service life
low installation time
Specification For Drawings & BOQs)
Structured wall pipe shall be high-density polyethylene conforming to SANS 21138 with stiffness class SN4 or SN8 and internal diameter as indicated on drawings. Pipe shall be GeoStruct™ or approved equivalent.
High Performance Drainage Solutions Guaranteed
Leading Supplier Of GeoStruct™ Structured Stormwater Pipes
As a premier structured wall HDPE pipe supplier, Geosynthetics Africa delivers high-strength drainage pipe systems engineered for stormwater, culvert, and infrastructure applications across Africa.