Approved AC-ROV operator Allied Marine Logistics (London, England) carried out the world’s first internal inspection of a crude oil offloading marine hose system offshore West Africa.  The AC-ROV was deployed and recovered from the rescue zone of an Anchor Handling Tug Supply vessel in 1m seas with a 1kt current.

The AC-ROV is the only ROV capable of completing this complex inspection,  with it ingressing a 12-24in flexible bonded rubber hose string.  The systems cube shape and vectored thruster design gives it the ideal profile for this kind of confined inspection work.  The alternative to in-situ hose bore inspection is to decommission the hose system periodically which is far more costly, reduces the availability of the terminal and runs the risk of damaging the hoses due to the additional handling.”

An external inspection of the hoses was also performed checking for loose bolts, third party impact damage, abrasion, kinking, leak detection devices and other early signs of deterioration.  The internal and external inspections were completed within 2 working days with no down time.

Inspectahire and Fugro Rovtech have deployed two AC-ROV systems on the Dong Energy owned North Sea based Siri platform.  The mission involved ingressing a seafloor chamber attached to the platform’s oil storage tank to inspect dangerous cracks that resulted in the rig being taken offline.  Operated by Inspectahire (Aberdeen, Scotland) a 120 meter tethered AC-ROV system was launched from the hydraulic manipulators of a Fugro Rovtech workclass ROV through purpose cut holes in the wall of the damaged chamber.  At 80 to 100 meters water depth the workclass ROV fed the AC-ROV’s tether through the hole as it flew into the chamber.  Deployed in this manor for three 10 hour sessions the role of the AC-ROV was to map the very congested internal structure of the chamber so larger ROVs could go in safely and continue the critical inspection work.  Inspectahire representatives explained that the “The Siri was one of the toughest ROV challenges ever faced and the AC-ROV did its job”.