Ductile Iron Pipes
General Description
Ductile Iron Pipes (DI Pipes) are one of the most reliable and timeless solutions for water, wastewater, industrial fluid transportation networks and special infrastructure applications.
They are made of ductile cast iron, a material that combines the high mechanical strength of steel with the resistance of cast iron to corrosion and subsoil stresses.
The pipes are produced in accordance with international standards EN 545, EN 598 and ISO 2531 and are used in water supply, sewage, irrigation, industrial installations and fire protection networks.
Key Advantages
High mechanical strength
Malleable cast iron pipes feature:
- Minimum tensile strength ≥ 420 MPa
- Yield strength ≥ 300 MPa
- Elongation up to 10%
providing excellent behavior in traffic loads, settlements and seismic actions.
Long lifespan
The expected lifespan exceeds 100 years when appropriate internal and external protections are applied.
Hydraulic performance
Smooth internal linings reduce pressure losses and limit the formation of deposits.
Corrosion resistance
With appropriate linings, pipes can operate in:
- marine environment
- aggressive territories
- industrial wastewater
- acidic or alkaline environments
Dimensions
Cast iron pipes are produced in nominal diameters:
| DN | Outer Diameter (mm) |
|---|---|
| DN80 | 98 |
| DN100 | 118 |
| DN150 | 170 |
| DN200 | 222 |
| DN250 | 274 |
| DN300 | 326 |
| DN400 | 429 |
| DN500 | 532 |
| DN600 | 635 |
| DN700 | 738 |
| DN800 | 842 |
| DN900 | 945 |
| DN1000 | 1048 |
| DN1200 | 1255 |
| DN1400 | 1462 |
| DN1600 | 1668 |
| DN1800 | 1875 |
| DN2000 | 2082 |
| DN2200 | 2288 |
| DN2400 | 2495 |
| DN2600 | 2702 |
The standard length dimensions are:
- 5,0 m
- 5,5 m
- 5,7 m
- 6,0 m
- special lengths upon request
Thickness Categories
K7
Suitable for standard water supply networks.
K8
Increased mechanical strength.
K9
The most common category for water supply and pressure projects.
C25 – C30 – C40
Newer categories according to EN 545 that optimize wall thickness depending on diameter and pressure requirements.
Connection Types
T-Type Connection (Tyton Joint)
The most common form of connection.
It is characterized by:
- rubber sealing ring
- easy installation
- angular deflection capability
- high tightness
Self Restrained Joint
Suitable for:
- high pressures
- large slopes
- address changes
- soils with subsidence
It offers increased resistance to pullout without the need for special concrete anchors.
Domestic Investments
Depending on the type of fluid being transported, the following are available:
Blast Furnace Cement
For drinking water and general water supply networks.
Sulfur-resistant Cementitious Compound
For wastewater and aggressive environments.
Epoxy Drinking Water Paint
Suitable for networks with high water quality requirements.
Polyurethane (PU) Coating
Offers:
- excellent abrasion resistance
- low roughness coefficient
- high chemical resistance
Epoxy Ceramic
For extreme environments and high wear resistance requirements.
External Protections
Available external protections include:
- Zinc Coating
- Zinc – Aluminum
- Epoxy coatings
- Polyurethane (PU)
- Bitumen coating (Bitumen)
- Special anti-corrosion coatings for marine environments
Special Types of Cast Iron Pipes
Water Pipes
For transporting drinking water.
Sewerage Pipes
With special anti-corrosion coatings.
Jacking Pipes
For microtunnel applications and projects without open excavation.
Gray Water Pipes
For recycled water networks.
Fire Fighting Pipes
For fire protection networks.
Flanged Pipes
With flanged connections for pumping stations, industrial facilities and special technical projects.
Field of Application
Malleable cast iron pipes are used in:
- City water supply networks
- Water transport pipelines
- Sewerage networks
- Industrial facilities
- Irrigation projects
- Pumping stations
- Desalination plants
- Fire protection networks
- Large diameter hydraulic projects
- Pipe Jacking Projects
Conclusion
Malleable cast iron pipes are today the leading choice for long-lasting infrastructure projects. The combination of high mechanical strength, excellent corrosion protection, high hydraulic efficiency and production capability in diameters up to DN2600 makes the system suitable for any modern water supply, sewage and fluid transport project.