Project closure report - Acoustek NIA_SGN0044

Abstract:

During the life of a pipeline there are occasions when a Network Licensee is required to excavate in order to enable the following activities:

The only existing method is to insert remote video cameras at regular intervals along the pipeline being surveyed. Typically, for remote video surveys, holes must be dug approx every 50 metres(m). Surveying long lengths of pipeline (> 100m) using this method is impractical. Other than remote video cameras there is currently no method to identify the exact location of problems or features of interest. Current techniques are typically multiple excavations supported (if appropriate to the problem under investigation) by pressure testing in the locality until the obstruction or asset can be found. There is a significant opportunity to reduce excavation, costs and time if a method to rapidly identify the location of features and causes of network problems can be developed.

Researchers at the University of Manchester had developed an acoustic monitoring system that was capable of surveying short and long lengths of pipe. The system had recently been commercialised for use in offshore natural gas pipelines and for surveying the relatively small tubes within shell and tube heat exchangers.

The system works by fires a sound pulse using a gas safe pulse injection system, it then "listens" to the return pulse waveform with a microphone, recording the reflected signal. The system analyses the return signal using purpose designed software.

The purpose of this collaborative project was to extend the technique and develop a tool that is capable of surveying pipes with lengths of up to 300m, diameters ranging from 25-200mm and rated for pressures of up to 350mbar, such that it can be used to survey the pipelines used in domestic gas distribution networks. The developed tool could be used for both planned and emergency reactive work in gas networks, where it has the following possible applications.

This document details the processes and learning from the project along with a summary of the field trials conducted which guide the recommendations and next steps. Following approval from all participating GDNs, this project began in May 2014 and progressed to field trial status in 2015/16. This document marks the closure of this project.

1. Introduction
2. Investment Proposal
3. Design and Development
4. Prototype System
5. Field Trials
6. Stage three -Test and optimise the prototype
7. Conclusion
8. Recommendation

• Appendix A - Stage 2 field trial results
• Appendix B - Stage 3 field trial results

Publication Year:

2016

Publisher:

Ofgem

DOI:

No DOI minted

Author(s):

SGN