Pipeline safety: The evolution of the smart pig

Smart pigs are sophisticated inline inspection tools used to ensure pipeline safety. Like small submarines, smart pigs travel inside a pipeline – using ultrasonic and magnetic technology similar to medical MRIs to detect and report issues to the pipeline operator.

Advances in technology have led to major changes to these pipeline inspection tools since they were first introduced in the early 1980s. And the improvements in the technology are making pipelines safer than ever before. Not only do they detect the smallest impurities in a pipe – the data they provide allows operators to forecast and predict potential issues that may arise in the future. This information ensures companies know exactly what is happening inside their pipelines and what they need to do to keep them safe and secure.

We spoke with Ziad Saad from ROSEN Canada, which designs and manufactures inline inspection tools. He told us they have an interesting history–even their name has a story behind it.


Named after squealing pigs?


Q. We’ve heard that smart pigs are named for the squealing sound they make as they pass through a pipeline. Is that true?

This is a common industry folklore. Some industry “old timers” will assert that, indeed this is the origin of the term. However, this continues to be hotly debated (and the debates are always fun!). There is no definitive consensus on the origin of the name. Many believe pig stands for “pipeline inspection gauge”.


History of inline inspection


Q. Could you please give us a brief history of inline inspection tools?

The early versions started showing up on the industry scene in the early 1980s. At the time, the tools were analogue and rather primitive in comparison to the complexity and sophistication of today’s digital tools.

The early version smart pigs would produce reels of paper – can you imagine, actual paper – with what looked like squiggly lines running across. These “channels” would represent a sensor output along the length of the pipeline segment and would have a somewhat regular pattern to them. Technicians would go through these reels and manually look out for any apparent deviations from the regular patterns. A location would be identified and a pipeline dig would be conducted to visually confirm if there were any pipeline anomalies at that location.

It was laborious and far from an exact science, but it was all we had at the time and was considered state of the art.


Evolving to ensure pipeline safety


Q. How have smart pigs evolved over the years?

While the basic approach has not changed much, what has changed is the sophistication and significantly increased capabilities of the tools. A number of different technologies are available to detect and identify different pipeline threats, including:

  • Corrosion (magnetic flux leakage tools or ultrasound tools)
  • Deformation such as dents (caliper tools)
  • Coating disbandment (electro magnetic acoustic transducer, or EMAT tools)
  • Pipeline movement (inertial measurement unit, or IMU, tools)
  • Cracking (EMAT or ultrasound tools)

The detection capabilities of smart pigs has increased dramatically. Tiny anomalies – mere millimetres in dimension – are detected. This may include pitting defects or stress corrosion cracking.

Finally, the software used for analyzing the recorded data is significantly more advanced. Manual review alone has become impractical as gigabytes and terabytes of data is collected in each inspection. Now sophisticated algorithms, incorporating forms of AI such as machine learning, are incorporated to augment the capabilities of the analyst. This ensures no significant anomaly is missed and proper identification of the anomaly type and accurate sizing is achieved.

Q. How advanced and innovative are today’s smart pigs?

Today’s smart pigs utilize cutting edge technology to ensure pipeline safety.

The tools are expected to collect very large amounts of data while operating in a very harsh environment. Smart pig sensors are required to function reliably in a range of temperatures (some specialized tools that ROSEN has built operate in hot bitumen pipelines up to 140 degrees Celsius). The smart pigs are used in all different oil and gas products that are shipped in pipelines, and must endure high levels of vibration and extremely high pressure all while maintaining high resolution coverage of the pipe surface.

I often compare smart pigs to medical diagnostic equipment such as MRI’s and ultrasounds. Except in this case, the machine has to travel and stay intact through hundreds of kilometers of pipeline during each inspection. However, the smart pigs themselves are only part of the story. Exceedingly, the techniques for dealing with all the collected data in an efficient and effective way to make proper decisions is a big part of the overall picture.


Smart pigs in the energy future 


Q. How will this technology fit into a lower carbon energy future?

As the industry strives to reduce its carbon footprint, new products are being introduced to pipelines such as hydrogen and renewable natural gas. Many pilot programs are underway as we endeavor to learn about the effect of introducing these new products into pipelines and if they pose new integrity challenges.

Also – as Carbon Capture Utilization and Storage (CCUS) becomes more commonplace, it is expected that we will see more and more CO2 pipelines. Similarly, these pipelines will require maintenance and also will introduce new challenges that the industry continues to understand better and devise the appropriate techniques to operate this infrastructure safely and efficiently.

Taking pipeline safety to a new level


The evolution of inline inspection tools, or smart pigs, has brought us into a whole new world of pipeline safety. This cutting-edge technology gives the industry more capacity to collect and analyze data – allowing us to see into the future and prevent incidents before they happen. This information is leading to improved results and is invaluable in our mission to reach zero incidents.

Special thanks to ROSEN Canada’s Ziad Saad for his contribution to this article.