There’s a shake-up happening in the pipeline inspections business. More evolved remotely operated vehicles (ROV), digital aspirations and unmanned surface vessels (USV) are driving a new era of data acquisition and deliverables.
It’s offering something of a revolution in the amount of new insights that operators can acquire on their pipelines, while reducing offshore campaign time.
Some of those operating in the space are Equinor, Shell and BP. A big driver has been reducing cost, as well as minimizing safety exposure. It’s the latest evolution in this space, Tom Glancy, Advisor Pipeline Mapping & Geographical Information at Equinor outlined at an October Hydrographic Society meeting in Aberdeen.
He says remote vehicle operation – during his own career – has gone from untethered manned submersibles (putting humans at risk) to ROVs, to unmanned underwater vehicles (UUV, usually referred to as autonomous underwater vehicles/AUVs, while not being wholly autonomous, highlights Glancy). While the move to ROVs removed humans from risk, the tether connecting them to a support vessel limited their scope. AUVs meant surveys could be done faster, but, AUVs weren’t able to stop and do detailed spot assessments if and when an issue was spotted.
A more recent evolution has been toward fast ROVs. Equinor has agreements with the two main providers, DeepOcean, using the Superior ROV, and Reach Subsea with the Surveyor Interceptor ROV, says Glancy. While both are tethered, they can survey faster than an ROV, at 4 knots (kt) compared with 2kt, says Glancy, thanks partly to their onboard HD imaging and laser packages. But, that does also means they come with a support vessel – and over overheads that comes with.
For Shell, with more than 200 pipelines and umbilicals, totaling 3,000 kilometers (km) in length, in the UK North Sea alone, easier, faster surveys is a tangible bonus. In 2018, Shell ran a new survey using DeepOcean’s “Fast Digital Imaging Service”. This involved a Kyst Design Superior ROV, with auto tracking capability, operated from the Edda Flora vessel on a 45-day nonstop campaign, starting in September 2018. The Superior was fitted with Teledyne dual head multi-beam echo sounders, Edgetech side scan sonar and sub bottom profiler, pipetracker, a CathX ultra-high definition (UHD) cameras (x3) and high specification inertial navigation. An ability to launch the vessel in up to 4.5-meter seas meant work could be started earlier in the season and run late into Autumn, says Shand, with speeds of 5kt in acoustic mode and 3.5-4kt for pipeline inspection.