Extensive investigation, has demonstrated that the majority of larger diameter tier 3 mains (18-48” diameter) are less likely to fail through cracks and fractures, and more likely to fail due to leaks within the existing joints.

In the past Network Licensees would either fully replace these ageing assets, which are a high cost activity, or aim to maintain them to prolong the asset life. To date the options available to repair large diameter joints have been limited to the use of mechanical joint clamps, encapsulation, or injection of anaerobic sealant into jute packing. While cheaper than full replacement, these repair techniques have a number of disadvantages including the costs incurred due to significant excavations and material requirements, and considerable disruption to SGN customers.

The objective at this stage of the project is to develop a liquid sealant for the repair of leaking joints from within a live pipe. This involves researching materials for the sealant as well as the tooling to apply the sealant into the joint, for deployment from a platform within the pipe. This must be deployed remotely or through a tethered system.   

• Successful production of a tested liquid sealant suitable for deployment from the inside of the pipe with a 50 year life expectancy.

• Suitable tooling to allow application of the sealant.

• Completed investigation and report into the potential of integration with a third party delivery platform.

• Completed study of sealant conveyance methodology to increase distance.

• Completed project reports.