Probes shed light on hidden corrosion

Laboratory modelling demonstrates the applicability and performance of sensor probes in underground soil conditions.

A series of research projects funded by Australia’s energy pipeline industry are paving the way for a world-first pipeline monitoring system based on a high tech sensor developed by researchers at the Institute for Frontier Materials (IFM).

Funded by the former Energy Pipelines CRC (EPCRC) and now supported by the Future Fuels CRC, the unique sensor-based pipeline health monitoring system should help the industry extend the lifespan of pipelines by decades.

“Pipelines are a multi-billion dollar asset in Australia,” says project leader, Professor Mike Tan. “They were designed to last for 30-40 years and many of Australia’s oil and gas pipes are near the end of that timeframe, but the companies would face huge difficulties and expense if they were to replace them.”

The technology being developed and commercialised at IFM should help the energy pipeline industry achieve its aspiration of a safe operational pipeline life of 100 years.

High pressure underground pipelines are typically protected against corrosion with a combination of barrier coatings and cathodic protection systems.

When their coatings become ‘disbonded,’ due to the effects of various chemical, electrochemical, electrical and environmental factors, pipelines become susceptible to corrosion that can eventually lead to leaks or catastrophic failure.

The current method to detect corrosion involves inserting a testing device which is carried along the pipe by the fluid flow. However, this is expensive and is usually only carried out at intervals of at least five years.

The sensors could play an important role in complementing that technique, with a focus on the outside of the pipes, where most of the underground pipeline corrosion tends to occur.

Over the past three years, the research team has carried out extensive field testing and comprehensive laboratory modelling to demonstrate the applicability and performance of these probes in underground soil conditions.

They conducted field tests by deploying probes in four gas pipeline locations and in a large sand box in Melbourne and Geelong. The results showed good agreement between the corroded surface image and the corrosion condition of the water pipeline after the probe was withdrawn.

The results provide the possibility for engineers to perform more proactive maintenance of major infrastructure assets. With the sensors, they can monitor the likelihood of corrosion continuously and the system can be adjusted well before significant corrosion takes place.

The possibility of extending the life of pipelines by being able to reliably monitor their safety and health has huge potential economic benefits.

For more information, contact:
Professor Mike Tan, Professor of Applied Electrochemistry and Corrosion