Remote Deepwater Coring and Sampling – Part 1
Compact remote methods of seabed geotechnical drilling, coring and sampling are being developed for deepwater operations and at the forefront of lightweight remote Geothechnical drilling are ROV systems combined to small drilling systems. Two companies, Forum Energy Technologies and Helix Energy Solutions, are leading the way in this technology. Forum Energy Technologies has been successfully employing its Rovdrill™ 3 system worldwide. This is Forum’s third generation Rovdrill system and it is where we will begin to look at the intricacies of these remote subsea coring and sampling systems.
The advantages of taking the coring/sampling rig to the seabed are obvious, both from a technical and economic standpoint. The rig itself can be very compact, easy to deploy, operate and recover without the need of specialized and expensive surface vessels or platforms, and once deployed, are free from the influences of sea state conditions and vessel/platform motions during sampling operations. However the surface deployment of the systems, still are dependent on sea and wind state. Rovdrill is a deepwater seabed drilling, coring and sampling rig that is integrated with a host work-class ROV. Designed and built as a collaborative effort between Perry and GEMS (Geotechnical Engineering and Marine Surveys) engineers, Rovdrill has a proven capability to perform applications for offshore geotechnical investigations and mineral explorations. Rovdrill provides many advantages over standard drillship operations, as it is compact, easy to deploy, operate and recover.
Rovdrill can be operated from a variety of ROV systems and vessels of opportunity without the need of specialized and expensive surface vessels or platforms. Rovdrill also has the advantage of being capable of operating in all seabed environments with multiple, interchangeable rig foundation options available. This creates a stable seabed foundation that maximizes core sample quality since it is free from the influences motion induced by vessel or platform movement. Rovdrill is capable of operating in water depths up to 4000 m. The coring/sampling depth is a standard 90 m, but is expandable to 200 m. Future trends such as subsea docking/recharging stations for ROVs and subsea wi-fi comms for both the ROV and the rig, promise to make ROV drilling systems even more flexible and needing even less surface support.