Ductile Iron Pipe - Saint Gobain PAM
September 2009 saw the start of construction on one of the biggest regional water and wastewater projects in Australia. The $189M Townsville Wastewater Upgrade Program, with the major works being delivered by Baulderstone Queensland, includes a new pipe product design supplied by Vinidex, previously unavailable in Australia.
The world leading manufacturer and exporter of ductile iron pipe systems, SAINT-GOBAIN PAM works as a privileged partner of industrial companies committed to designing drinking water supply, sewage or fire protection networks. SAINT-GOBAIN PAM has considerably extended its product offer (pipes, fittings, hydrants, valves, couplings and street fixtures), making it possible to implement all systems, from the simplest to the most complex.
Vinidex is proud to be Australia's leading provider of Saint Gobain Ductile Iron pipe and fittings.
Pipe Benefits
- A high tech coating system that can negate the need for protective polyethylene sleeving at installation
- DI fittings systems and maintenance systems readily available now in the Australian market from a number of sources including Vinidex Superlink® DI fittings
- Provides a high quality competitive alternative to traditional DI pipe systems supplied into the Australian market
- The system is supported by Vinidex who provide Australian corporate strength and have 50 years of success in supplying the Australian market. Vinidex has a commitment to stocks, and has systems and procedures in place to ensure the safe and efficient distribution of the products
- The Saint-Gobain pipe system has undergone WSAA appraisal and has Australian standards product certification
- Has product approvals with most major Australian water companies
- Vinidex and Saint-Gobain have experience in supplying major projects here and overseas. AS2280 pipes for the Australian market are now in full production with stocks on the ground.
Performance benefits also include:
- Material and energy efficient options available - environmentally more sustainable
- High impact strength
- High toughness
- Excellent damage tolerance
- High fatigue strength
- Jointing - Pipe jointing will be made in EPDM in accordance with AS1646
- Fittings - The existing ranges of VX DI Superlink® pressure fittings available in the Australian market are fully compatible with SAINT-GOBAIN Pam DI pipe system pipes.
Linings & Coatings
Internal protection
PAM ductile iron pipes will be internally lined with cement mortar. The cement mortar lining is in accordance with the Australian Standard AS3972 with the thickness given in following table:
The basic internal protection for PAM pipes is a cement mortar lining applied by centrifugal action.
This process has the advantage of producing a sound mortar with a smooth internal surface.
This results in the following properties:
- High mortar compactness
- Good bonding to metal
- Low surface roughness
Cement mortar has a very smooth inner surface, which enhances flow and reduces head losses. This mortar guarantees hydraulic performance is maintained over time (absence of deposits).
When such circumstances are feared or known to exist, ductile iron pipes may need a passive lining, such as PUR (polyurethane lining in accordance with EN 15655) which will allow the system operator to benefit from all the properties of ductile iron, even under adverse conditions.
The roughness coefficient (COLEBROOK formula) for a pipe alone is k = 0.03 mm. SAINT-GOBAIN PAM recommends using k = 0.1mm in practice when designing a pipe system in order to take any peculiar head losses in the complete main into account.
The cement mortar lining protects both pipes and drinking water:
- Protective mechanism. The cement lining does not act merely as a barrier, but protects the iron through a passivation mechanism: during the filling, water gradually soaks into the mortar and absorbs alkaline compounds; by the time it reaches the metal wall, it is consequently non-corrosive
- Crack plugging. Crazing (hydraulic shrinking), or even small cracks occurring during transport, storage or laying, close up through the combined effect of two reactions: rapid mortar swelling on exposure to water and low hydration of the cement’s constituents
External protection
The following table shows the different coatings used by Saint-Gobain PAM. The coating is chosen according to the nature of the soil. If needed, Saint-Gobain PAM can conduct a soil survey to get more details about potential risks.
- A metallic 200 g/m2 zinc + a bituminous varnish or equivalent anticorrosive paint (Standard PAM® Range)
- A metallic alloy zinc/aluminium 400g/m2 + a blue epoxy (Natural® Range)
- A Polyurethane PUX 700µm coating with a spray-applied
The coating of SAINT-GOBAIN PAM pipes consists of a layer of metallic zinc or Zn/Al spray applied and covered with a finishing bitumen or epoxy paint. This is an active coating suitable for the vast majority of soils.
Zinc metallization is an active protection due to the galvanic effect of the zinc/iron electrochemical couple. Its mechanism is twofold:
- Formation of a stable protective layer:
In contact with the surrounding soil, the metallic zinc slowly transforms into a dense, adherent, impermeable and continuous zinc salts. This acts as a protective barrier. The pore sealer, whilst permitting galvanic protection and self-healing, favors the formation of a stable and insoluble layer of zinc conversion products.
- Self-healing of damage:
One of the particular features of the external zinc coating is its ability to restore the continuity of the protective layer where small areas of local damage exist. The Zn++ ions migrate through the pore sealer to plug the damage and then convert into stable, insoluble zinc corrosion products.
SAINT-GOBAIN PAM has chosen to raise the zinc quantity to 200 g/m (instead of the 130 g/m prescribed by the standards). 50% of extra zinc ensures a significant increase in the galvanic protection’s life span.
In experiments carried out at the SAINT-GOBAIN PAM Research Centre, two identical notches were practiced on samples and then immersed in a highly corrosive medium.
AS2280 Pipe Classes & Pipe Dimensions
SAINT-GOBAIN PAM DI pipe system pipes are classified in terms of their nominal working pressure at 20°C. Pressure classes are identified by their PN designation as shown in the table below:
Australian & International Series
International Series
Ductile iron socket and spigot PAM STANDARD ductile iron pipes will be centrifugally cast in accordance with the European standard EN 545 (2006) and with ISO 2531 (1998). Each pipe is subjected to a hydrostatic works test, in accordance with the European Standard EN 545 (2006). Size range 100mm – 2000mm
NOTE: International pipe specifications and dimensions available on request
Australian Standard Series AS2280.
Ductile iron socket and spigot PAM pipes will be centrifugally cast in accordance with the Australian standard AS2280. Each pipe is subjected to a hydrostatic works test, in accordance with the Australian standard AS2280. Size range 100mm – 750mm
To download a PDF copy of this information:
Ductile Iron Pipe Systems Vinidex Saint Gobain PAM (1.63 MB)
For more information please click on the link below or call Vinidex on 13 11 69: