Civil Pipe
INFRAPIPE produces pipe for gravity sewer and storm water applications and low pressure potable, sewer and storm water applications. These are made in a state-of-the-art Krah machine from Europe. Pipes are manufacHelical wound HDPE is the ideal solution for most civil engineering pipe requirements because it has the following benefits for the asset manager, design engineer or contractor:
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- Email: [email protected]
- Office: 3 Averton Place East Tamaki Auckland 2013
- 100 year asset life
- Fully recyclable and all production waste is recycled
- Smooth bore means better hydraulic performance
- Faster installation speed
- Fabricated bends mean less expensive manholes
- Access hatches mean less expensive manholes
- Lighter weight means less, cheaper diggers
- Lighter weight means less freight costs
- Lighter weight means a safer trench
- Longer lengths mean less joins
- Manufactured to the exact SN rating required
- Optimum seismic resistance
- Optimum abrasion performance
- Better hydraulic performance can mean smaller pipes required
- Less prone to damage on site or during installation
- Chemically and biologically inert means less decay
- No maintenance means no cost for the asset owner
If you are an engineer, asset manager or contractor, download this Guide to Stormwater applications which has everything you need to know.
SN Rating
The Ring Stiffness Rating (SN) of the pipe is dictated by the native soil, the cover height, the water table and the loading. Alternatives to PE are only manufactured in a couple of strengths, but the unique nature of the spiral wound product means that pipe can be designed for the exact ring stiffness required for each pipeline, each section of that pipeline or even each individual pipe. This saves money directly in the product manufacture and then in weight, freight and trench size. For those converting from concrete, Class 2 equates to SN16 and Class 4 to SN4.
Design software selects the most appropriate core tube size and varies the core tube spacing and thickness of inner and outer layers to achieve the required strength with the minimum material (with a significant 25% safety factor)
Sustainability
HDPE is completely recyclable and all excess or waste product is reprocessed by INFRAPIPE. NZS5065:2005 does not permit the use of third party recycled product but for non-civil applications INFRAPIPE uses post-consumer recyclate (PCR) in its pipes. Pipes at the end of their working life will be entirely recycled and become pipes again. INFRAPIPE observe that while concrete is theoretically recyclable, most production or site waste is buried. See this page on Sustainability for more information.
Pipe dimensions
INFRAPIPE can manufacture in a range of sizes from 450 to 3200mm in diameter as shown below. For these pipes the DN – the name – is the ID unlike some alternatives which sound 15% bigger than they actually are. The table below shows the cross-sectional area of the pipe – and its equivalent in smaller pipes (shown by their ID). For use where burial is required, the cross-sectional area with 25% burial is also shown. Weight and OD are shown for the typical sizes for light duty and heavy duty applications; the OD is used for trench dimension calculations.
Standards
INFRAPIPE is accredited to ISO 9001:2015 and the pipe is certified to ISO Type 5 5065:2005, these certificates can be provided on request or found on the INFRAPIPE website. Producer Statements and Certificates of Conformity can be issued by INFRAPIPE on request. Overall testing is in accordance with ISO 5065:2005 and raw material used is tested for Melt Mass-Flow Rate (MFR) in accordance with ISO 1133-1:2022 Plastics – Determination of the melt mass-flow rate and melt volume-flow rate of thermoplastics. All resins used are certified to AS/NZS 4131:2010 and batch certificates are retained.
Installation Instructions are in accordance with AS/NZS 2566.1:1998 Buried Flexible Pipelines: Structural design and AS/NZS 2566.2:2002 Buried flexible pipelines – Installation. Manufacture of the product is designed to DIN16961, EN13476, ASTM F894 and ISO 9969.
Bends
No more expensive manholes for every change of direction! INFRAPIPE can be fabricated into any angle. Now the pipeline suits the site not the site being designed around the pipes and manholes.
The example below is from the worlds largest water treatment plant, completed in 2023 in Egypt. It also proves that HDPE pipes are the best option when faced with the poorest soils which can barely support a human:
Joining the pipe
INFRAPIPE has an effective length of 5800mm (pipe length 6000mm)
Shorter lengths can be produced which means there is no waste and the asset owner is not charged for a length of pipe which then has to be cut and the offcut disposed of. Pipes can be joined in factory for a delivered length of 11.8m or longer.
Whilst joins are normally located at full pipe lengths (effective length is 5800mm) the presence of bends and structures can require them to be located at shorter lengths; Infrapipe will calculate this.
There are two types of joins used for INFRAPIPE; Double Rubber Ring Joint (RRJ) is the standard join which is conducted by contractor staff onsite. Each join takes approximately ten-twenty minutes in good conditions (dependant on pipe size).
Electro Fusion (EF) Welds are performed onsite by INFRAPIPE specialist personnel or by contractor personnel who have been trained by INFRAPIPE. This is a much more sophisticated process than the small EF couplers used – see more detail on EF welding process. EF welds take approximately one hour each, depending on pipe size, during which time the next pipe can be laid in the trench ready for insertion and joining.
EF welds are essential with significant grades or where the pipe is pressurized and are preferred by some asset owners for all waste applications as there is no possibility of infiltration.
The gradient at this project in Wharenui Rise required EF joins because of the 22% fall. Once welded nearby, it then took 2 minutes 47 seconds for three diggers to position the entire 51m section next to the trench. See this video of the installation
Can INFRAPIPE join to existing concrete?
EASILY WITH A FITTING LIKE THIS:
This Manhole ‘starter’ is a very effective, reliable and easy to fit means of joining HDPE pipes to concrete structures. For joining HDPE pipe to concrete pipes INFRAPIPE uses a slip coupler:
Solid Wall Alternatives
The KRAH Technology can also create solid wall pipe which can be much more economical than traditional inline extrusion (which has large setup costs) for shorter runs of larger diameters, or more extreme wall thicknesses. Whilst the table below shows the most common SDRs (Standard Dimension Ratios – which dictate the wall thickness for a given pressure rating), INFRAPIPE can achieve any SDR.
Emergency repairs
There is no tooling setup or curing time for INFRAPIPE – pipe can be made and used immediately. When Nelson main water supply was washed away in Sep 22, INFRAPIPE despatched a truck load of replacement three days later.
Spiral HDPE is the pipe of choice in the earthquake prone Philippines for supplying the hundreds of hydro electric schemes as it can be quickly and easily repaired after a seismic event. The pipe itself Is not damaged by the earthquake, but then the hill side falls away afterwards!
Trench Design & Cover
INFRAPIPE will advise on the specific trench design and cover height when supplied with Geotech and water table data, to minimize installation cost. The general details of trench and cover requirements are below, and available in This Handling & Installation Guide
