French tubular solutions specialist Vallourec is working with its compatriots Forssea Robotics and iXblue to develop a pipeline inspection solution combining subsea drones and the use of visual markers, removing the need for surface vessels.
Traditionally, the inspection of subsea pipelines and structures requires the use of a surface vessel with acoustic positioning used to monitor the deployment of autonomous underwater vehicles (AUVs) or remotely operated vehicles (ROVs).
These subsea vehicles then collect the required information – such as a pipeline’s general aspect and route, anode consumption, free span, burial and crossing areas – using observation sensors.
In order to reduce pipeline inspection operational costs, Vallourec, iXblue and Forssea decided to develop a solution using visual markers directly integrated on subsea pipelines that enables vessel-free subsea navigation.
The project relies on bar codes placed on installed pipes, resulting in many passive positioning references logged with their own coordinates during the laying operation which will remain accessible throughout the life of the field.
These markers would be navigation aids for subsea drones with Forssea cameras and iXblue’s inertial navigation system that easily relay the pipelines’ locations to the operators thus removing the need for acoustic positioning systems and costly mother vessels.
To remain visible to divers and subsea drones throughout the project’s lifespan, these markers are long-term resistant to marine growth and erosion.
“This technology had already proven itself on large structures in the field,” said Jean-Guillaume Besse, Vallourec’s R&D project leader. “Back in January 2020, we did a first sea trial on much smaller surfaces – down to pipes of 6” in diameter – in the South of France. The tests were a success, proving that these markers, combined with iXblue’s and Forssea’s expertise, can be used to provide accurate subsea positioning without the need of acoustic systems.”
This inspection technology could advance further when combined with existing digital solutions from Vallourec smart’s services portfolio. For example, the Smartengo Best Fit digital solution already associates a unique tag on each pipe to ease traceability, fit-up and pipeline construction.
The advanced solution developed with Forssea and iXblue could be the next step in the Vallourec.smart offering, further facilitating operators’ asset management.
This article originally appeared in Offshore Energy magazine, which owns all rights. Reprinted by permission. For more information, visit offshore=-energy.biz
Republished from Marine Construction Magazine Issue IV, 2021