Skip to main content

Novel Technology for Low Cost Re-lining of Pipe Infrastructure

Final Report Summary - EZ-LINE (Novel Technology for Low Cost Re-lining of Pipe Infrastructure)

Executive Summary:
Much of the water pipe infrastructure in European cities requires frequent maintenance and repair, with older cast iron and clay pipes being particularly problematic. Over 2.6 billion cubic metres of drinking water are lost each year through leaks. For example In Italy more than 40% of pipe infrastructure need to be repaired, mostly in rural district., Every day in England and Wales, more than 3.3 billion litres of treated water are lost through leaking pipes. The water lost would meet the daily needs of 21.5 million people and despite ongoing expensive repair and maintenance programmes, the losses are getting worse. Compared with a decade ago, an additional 234 million litres of water is lost each day. This is caused by a number of factors including heavy traffic in cities where vibration can lead to fatigue and cracking. The age of pipe infrastructure is another important factor. In London for example, over 20% of the pipe infrastructure is over 150 years old and in poor condition. Climatic weather extremes are also causing the ground to experience very wet and dry periods which can cause pipes to fracture through ground movement, expansion and contraction.

Overall, a large proportion of the European pipe infrastructure requires repair. Leaks are wasteful of water, energy and water treatment resources. In hotter European countries where water resources are less plentiful, the need to conserve and manage resources is of great importance and urgency. Repairs can be costly and very disruptive, particularly where a trench must be dug to undertake complete pipe replacement.

Increasingly stringent European legislation on drinking water quality is also creating significant demand for pipe rehabilitation programs to be undertaken. To date, such programs have been most extensively undertaken in North Western regions of Europe (e.g. UK, Scandinavia, Germany, Netherlands and France). Even in these locations, remedial works are progressing slowly and will take many years to complete, while in many of the eastern and accession states they have yet to start. In addition, tight margins, large liabilities and rising insurance costs are putting pressure on SMEs working in the pipe repair sector.

In most cases, repairs continue to cause disruption and high costs are incurred for every hour needed to complete the repair. The situation is now largely regarded as unsatisfactory, even by the industry sector. There is on-going political demand for better infrastructure, and subsequently, higher demand for more efficient and lower cost repair processes. Although the pipe rehabilitation market is mature, it has failed to develop cost effective, rapid relining solutions that are capable of addressing the aforementioned issues.

In response, the industry has developed repair methods which increasingly involve relining old pipes in-situ, thus eliminating complete pipe replacement. These ‘trenchless’ technologies offer many advantages also in social sustainability and low environmental impact.

This project is highly innovative as it has anticipated a matter which has become one of the pillar of Horizon 2020.

Pipe related activities (new construction and rehabilitation sectors) within Europe, comprises some 32,500 SMEs of which an estimate 1,600 SMEs work in pipe rehabilitation, directly employing 14,000 people and rehabilitating some 4,900km of water and sewerage pipes per year (25% of the total market).

Recognising the problems and opportunities in the pipe rehabilitation sector, the EZ-Line project was conceived and subsequently supported financially by the European Commission under Framework Programme 7, a scheme supporting research and development activities within Europe. The project, administered through the REA, has been led by the Italian Association for Trenchless Technology (IATT) with partner associations representing SME members across Europe engaged in pipe rehabilitation. The EZ-Line Consortium members included companies involved in many aspects of ground works including installation, cleaning, pipe rehabilitation and fibre based reinforcement solutions.

The EZ-Line Consortium members were as follows:-

1) IATT (Coordinator) – Italian Association for Trenchless Technology, Italy – SME AG
2) PFTT – Polish Foundation for Trenchless Technology, Poland – SME-AG
3) TechniTex, UK – SME-AG
4) Sirris, Belgium – RTD
5) UKMatRI – UK Materials Technolgoy Research Institute, UK – RTD
7) Centrocot – Centro Tessile Cotoniero e Abbigliamento Spa, Italy – RTD
8) GAdmon Industries, UK – SMEP
9) CEPA – Controlloe Energia e Protozione Ambiente srl, Italy – SMEP
10) Longrock Ground Works Ltd, UK – SMEP (replaced Timco in 2012)
11) Eurocarbon B.V. Netherlands – SME
12) Medworks srl, Italy - RTD

The primary objective of the project was to develop a cheaper and faster repair technology that could provide effective and durable pipe repairs in a trenchless environment. The benefits delivered by the EZ-Line project, successfully completed early in 2014, are summarised below.

The EZ-Line principle involves pipe relining. This approach eliminates the need for total pipe replacement and only requires access to each end of the pipe requiring repair. EZ-Line therefore offers a trenchless solution, eliminating the need for major excavations along the pipe run.
More over the expenses bearded by network agencies, being Public or Private, for the repairing and rehabilitation of pipe infrastructures should be attributed to the “asset” thus increasing their value.

The pipe is first inspected and cleaned prior to the repair being undertaken. Debris is removed as required and as much of the original pipe as possible is left in place. Once the pipe diameter is confirmed, a thermoplastic liner is prepared prior to the repair being undertaken.

The liner is deformed into a unique shape which reduces the effective diameter. This is achieved using an innovative single stage forming process utilising a tension controlled winch system. The liner is then pulled through the defective pipe with minimal pulling force since friction between the pipe and liner is reduced. The liner can optionally be braided with reinforcing fibres before the diameter reduction process is carried out. This offers a means of increasing the burst strength of the liner where high water pressures will be experienced, or where there are significant discontinuities in the original pipe structure. Once formed, the liner can be held in stock indefinitely until it is required.

After the deformed liner is positioned in the pipe, one end is anchored to prevent longitudinal movement. The EZ-Line process then expands the liner back to its original dimensions using a thermal and mechanical deformation process. It is a modular consolidating head, called PIG, which initially heating the novel liner so it can easily be formed into a tubular geometry. After forming the liner will be immediately air cooled so that it maintains the tubular shape. The PIG has an umbilical cabling and sensors controlled by remote. If reinforcing braids were specified, these now provide a circumferential reinforcement in contact with the external surface of the liner.

The project Consortium successfully demonstrated the EZ-Line rehabilitation process at the UK Materials Technology Research Institute (UK MatRI). The trial demonstrated relining of a clay drainage pipe of 150mm internal diameter and 8m length. The clay pipe was buried in wet soil and sand to represent realistic ground conditions. The relining process was carried out using prototype equipment at a speed of 6 metres per hour. It is anticipated that this speed will increase significantly when commercial equipment rated at higher capacity is used.

Following repair of the clay pipe, the interior liner surface was shown to be smooth and defect free. Therefore, a durable repair solution with high levels of integrity is provided by the EZ-Line process. The conclusion of the Consortium is that the process can be adapted to a wide range of relining industries and provides a low cost, rapid relining solution with minimal disruption. In addition this relining method by thermoplastic liner, instead of traditional methods, eliminate the eventual risk of contamination from chemical agents. Further, the technology can be tailored for a variety of pipe diameters and thermoplastic liner materials as required by current legislation. Optional braiding can be used with the liner to provide additional strength and pressure capability.

In summary, the EZ-Line process provides a repair solution that:

• Is capable of relining a wide variety of pipe diameters
• Utilises a trenchless technology with low environmental impact and high sustainability
• Provides a smooth and durable inner repaired pipe surface
• Can be used in pipes with significant structural defects
• Achieves a close fit to the original pipe, maximising pipe capacity after relining
• Complies with current legislation
• It is less labour intensive process resulting in lower labour costs
• It is a technology capable of relining longer runs of pipe in a single operation
• Allows the use of reinforcement braiding for higher pressure applications
• Eliminates the use of hazardous solvent based resins, as used by some competitive systems
• Provides a solution that is attractive commercially whilst minimising disruption during repair
• Removes the risk of chemical contamination into water supplies from the liner

More information can be obtained at web address http://www.ezline.info

Project Context and Objectives:
The project vision was to create an innovative rehabilitation process designed to meet the needs of the pipe rehabilitation market and the SME-AG members:-
- A low cost system (33% reduction in total costs compared to cured in place resin lining)
- A high production rate system (2 x the production rate of cured in place resin lining)
- A low maintenance solution with suitable operational characteristics (long life time and flexible use for fresh and waste water)
- Reduced energy use (a 15% reduction over cured in place resin lining)
- Ready ability to deliver c. 250m contiguous lining runs
- No increase in infrastructure cost
- Integration with existing working equipment and tools

The EZ-Line solution comprises a conformable solid thermoplastic composite liner with integral fibre re-enforcement, which is supplied in a collapsed format, pulled through the host pipe, and pushed and consolidated against the inner surface of the pipe to be relined with a heated novel install PIG design.
During consolidation in the host pipe, the liner fabric will re-assume its original circular shape to form a smooth, water tight solid ‘sheet’ of reinforced plastic.
The EZ-Line system would use standard commercially available pressure water jet cleaning technology to clear debris in the pipe and clean it prior to the lining process.
The EZ-Line system will use a unique heated, articulated pig design to ensure rapid processing and relining of the damaged pipe; placing the liner in situ and consolidating the structure as it traverses along the length of the pipe. This simplifies the design to produce a very robust device.
The EZ-Line system will not require water pressure to ‘push’ a sock into the pipe (as required for thermosetting resin impregnated felts); neither will EZ-Line need hot water or steam to carry out any chemical curing process.
The lining technology will allow longer relining runs to be undertaken using a trenchless technology. The liner will take the form of a star-formed collapsed reinforced thermoplastic composite, envisaged to be spooled on a reel for delivery on-site.
Compared to existing processes, infrastructure requirements would be minimised. The benefits to include faster, lower cost, efficient repairs, with reduced labour, reduced risk and no smell or chemical hazards typically associated with thermosetting resins in the cured in place process.
The consolidation head will provide electrical heating for liner softening and re-forming and a cooling method for retrospective consolidation, these provided by an umbilical cable fed from a control and power unit.

General Project Objectives
The overall objective then was to design, develop and create a novel trenchless pipe relining solution for:-
- Renovation of underground non-pressure drainage and sewerage networks
- Renovation of underground drainage and sewerage networks under pressure
- Renovation of underground water supply networks
- Also for consideration, renovation of underground gas supply networks and industrial pipelines
Standards were to be represented by the related ISO norms, in line with cured-in-place pipes, using ISO EN 13566- 4:2002 as a benchmark and as the standard used for this project.

Project Results:
To achieve the project objective of establishing EZ Line as a technology, to benefit the SME-AG members, the partners needed to address the following scientific and technical objectives : -
Scientific
- Enhanced scientific knowledge of thermoplastics for the liner
- Enhanced understanding through experimental analysis of textile solutions
- Enhance understanding of polymer forming, heating and consolidation processes
- Enhanced understanding of fabrics development and consolidation of requirements
Technical
- Development of former tool
- Development of install PIG and head, consolidation, monitoring and umbilical systems
- Validation of mechanical properties for the consolidated liner
- Integration of components and fabrics to produce a prototype demonstration system

Potential Impact:
On behalf of pipe rehabilitators (represented in the consortium by CEPA and Gadmon):-
- Total savings in relining costs of c. €279 million pa in the EU by 5 years post project

On behalf of machinery manufacturers (represented in the consortium by Longrock):-
- Direct sales of machinery of up to a cumulative value of c. €10.2million in the EU and c. €5million into the Rest of World market by 5 years post project with an additional revenue of some €2.5m pa from year 6 onwards

On behalf of textile/fabric manufacturers (represented in the consortium by Eurocarbon):-
- Direct sales of liner materials in excess of c. €41.5 million pa 5 years post project

On behalf of communities, and other employment factors, within the EU:-
- The protection/creation of c. 337 jobs pa within EU SME companies
- Creation of sustainable employment and protection of communities

List of Websites:

The Ezline project website is available to the members of the Project Consortium.

A general website is available for public viewing and access:-

www.ezline.info http://www.iatt.it/index.php?option=com_content&view=article&id=268&Itemid=118&lang=it

The project co-ordinator for the Ezline project is:-
Sergio Bianchi
c/o IATT
Via Ruggero Fiore, 41
00136 Roma
Tel. +39 06 39721997
iatt@iatt.info www.iatt.it

Responsible for the web portal is Letizia Rinaldini iatt@info.it