Control Cutter AS has successfully released the mooring lines on ExxonMobil Canada’s Hebron platform, which is now being towed to its permanent location. Each of the 120mm mooring lines was cut in less than 15 minutes by Control Cutter’s new Subsea Cutter.
During its construction, the Hebron platform—which measures about 220 meters in height and weighs about 750,000 tonnes—has been moored in Trinity Bay via nine 120mm R4 links. These major mooring chains needed to be released to allow the platform to be towed to its permanent location in the Jeanne d’Arc Basin, offshore Labrador and Newfoundland.
Control Cutter’s Subsea Cutter for was tested and qualified by ExxonMobil Canada and KKC in November 2016, and verified to operate with any type of ROV system. An agreement was signed in January 2017 to design and deliver six systems by the end of March.
After cutting the first three mooring lines in April, the six systems were installed on the remaining mooring lines in May. The plan was to release the Hebron platform when the tow fleet—including 8 large, anchor-handling tug supply vessels—had been attached and were ready to tow the platform to its final location.
On the 2nd of June, the six remaining mooring lines were released using the Control Cutter Subsea Cutter. All cuts were achieved between 10 and 15 minutes. The Subsea Cutter was deployed using a ROV system without any umbilical or strings attached from the surface.
“This is a major achievement for Control Cutter,” says founder and CEO, Petter Birkeland., “I would like to thank ExxonMobil, KKC and the Hebron team for giving Control Cutter the opportunity. As the first application of our new Subsea Cutter, we are extremely pleased with the performance of the tools. This adds momentum to a series of new projects where we have qualified the system to additionally cut large flexible risers, conductors and casing in less than 5 minutes.”
ControlCutter AS, established in 2010, is a privately held, Norwegian company formed to develop and commercialize a unique technology for rapidly cutting resistant metals. The patented technology comprises a self-contained system that generates immediate hydraulic power to knives composed of a proprietary alloy. It has been successfully field tested and verified and has been shown capable of cutting steel up to 167 mm in diameter.
In June 2017, Control Cutter was qualified by Statoil to perform the cutting of various types of subsea flowlines and pipelines. On September 6, cuts were carried out on a 10″ flowline at Troll B. All cuts were successfully completed in less than 5 minutes, a key factor in minimizing vessel time. But ControlCutter technology has additional benefits. For example, it is unaffected by internal forces and possible twisting of the object being cut. This is because, once ControlCutter’s knives have latched onto the object to be cut, the tool will ignore any twist and will correct itself. Also, ControlCutter is capable 100 cuts or more on the same run, thus avoiding unnecessary returns to the vessel as with other cutting technologies.