Internal FPSO turret scan

The Operation

While planning for a mooring line chain out, our client noted that the status of numerous components inside the FPSO turret below the water-line was unknown.

We were tasked with helping to choose a suitable marine contractor, planning and executing an internal 3D scan of the chain table, as well as ascertaining the status of these components, and whether there were any anomalies within the turret.

The client elected to use Viewport3 for the task due to the flexible nature of the scanning process and our ability to innovate to overcome project challenges.

The Challenge

The scanning was focused inside the chain table of a North Sea FPSO turret.  Cramped working conditions and the use of a small form factor ROV made this a challenging scanning contract for the team.

The Solution

We worked in conjunction with a marine contractor with previous experience on the FPSO, whereby both reported directly to the operator.

During a period outside of the annual maintenance, ROV operations were conducted from a gravity-based structure ROV spread on the FPSO.  Viewport3 designed and built custom equipment to assist in the operations, and mobilised the applicable equipment to have a single one-stop scanning hub on the FPSO.

ROV dives were conducted during weather windows and timed with other FPSO operations.  The capture data was completed and subsequently verified onboard the FPSO in the client’s presence.

The Result

The end scanned data was of high quality thanks to both the planning conducted by Viewport3 and the marine contractor’s willingness to innovate while offshore.

The final product was rendered, and fly-throughs were produced to enhance the initial planning, as well as reverse engineering of the point-cloud data. This was used to ascertain dimensions and locations of the welds within an I-Tube for a future Riser install (an optional extra mentioned during the upfront tendering scope). The data also provides an interactive 3D environment which client will use to aid efficiency of dive planning activities.

The flexibility of Viewport3’s capture system and onboard verification enabled the client to see the data and also to request extra work to be conducted while we were onsite – in essence alleviating a future mobilisation offshore in 2020.

In Numbers

Despite there being limited windows for diving, our flexible use of experienced people reduced the actual scanning time inside the turret to just under 6 hours.

Furthermore, the operation gave the client the answers they needed well within the deadline.

It was the first contract of this type for Viewport3, which saw us undertaking asset based 3D scanning, but the second within a ‘decom’ setting.