TECHNOLOGY
Saipem Sonsub – Solves Statoil Norne Heidron Deepwater Tie-ins with BRUTUS Saipem Sonsub, with main technology centres in Venice and Aberdeen is presently engaged in upgrading the BRUTUS Tie-in system for an important Statoil Subsea project in Norway for replacing a Norne Gas Export Riser. The BRUTUS system can perform deepwater connections of “rigid to rigid pipeline” and “riser to subsea structure” in any combination utilising spool pieces or flexibles and implementing standard bolted flanges as the preferred connector. The tie-in can therefore be utilised for pipeline repair by spoolpiece inclusion. The system provides the means of alignment and connection of a rigid repair spool. The system is based on a suite of modular tools, each one neutrally buoyant, installed and operated by a work class ROV. The system can operate on line sizes between 8” and 26”, and the system has completed connections on both 16” and 26” pipelines. The working philosophy centres around the following concept: The flanges to be connected are pulled together and aligned by two spools, each one sitting behind the relevant flange. The idea is to create a single structure starting from the two tools and use its strength to counteract the required pull-in and alignment loads. These tools are called the Reaction Tool (RT) and the Axial Force Tool (AFT).
In 2003, Saipem were awarded the Kvitebjorn pipeline tie-ins project by Statoil. This project involved a further upgrade of the BRUTUS system to accommodate 26” flanges. The BRUTUS system was mobilised in Summer 2004, and successfully completed the four connections. Pipe handling and spool alignment were performed remotely utilising H-Frames. A Saipem Sonsub project Team based in Aberdeen was assembled in January 2013, and after six months of intense refurbishment, BRUTUS has been fully re-assembled, tested to be delivered to the West Coast of Norway, off Bergen, to clients Statoil.
“We have a very strong track record in conceiving, designing, engineering and building diverless Pipeline Connection and Pipeline Repair systems,” said Massimo Fontolan, who heads up Saipem’s Sonsub Division.
The Flange Connection Tooling (FCT) carries all the bolts and nuts together with the bolt tensioning equipment, and is provided with functions to perform the connections remotely by ROV. The BRUTUS system was conceived in 1997 and developed with backing from Saipem, and in 2000 completed the tiein of two 16” rigid steel pipeline systems and a 10” flexible riser to subsea structure for Statoil (a total of seven flanged connections for the Norne-Heidron project in the Norwegian sector of the North Sea).
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Subsea UK News | September 2013
Above: BRUTUS – A diverless horizontal flange connection system Below: Graphic showing AFT positioned on pup piece, RT installed on spool piece and tool deployment basket on left