Subsea tool specialist Seatools, with companies in the Netherlands and Norway, delivered the first system to Bergen-based Oceanteam and its Mexican partner Diavaz during 2002; two more systems were delivered in April and September this year. All three units are second-generation mass-flow excavation systems designed to cope with the highly-variable soil conditions encountered in areas such as the Gulf of Mexico, and cutting capabilities have been enhanced to tackle stiff clays of up to 50kPa.
The first of the three units is already in service, mounted on the DP-equipped offshore support vessel Midnight Arrow, and is being used to expose and correct pipeline crossings in the Cantarel field, offshore Mexico. The Oceanteam/Diavaz joint venture’s deburial contract is a preparatory phase for pipeline anode replacement. The other two systems will be chartered out to Canyon Offshore. One unit will start working in the Gulf of Mexico in US waters, while the third unit will be mobilized to Vietnam.
The multi-purpose excavation system evolved from a close relationship between Seatools and Oceanteam engineers. The outcome is an efficient, cost-effective, solution for the removal of sandbag stabilization and other materials from existing pipelines in combined soils consisting of sand, gravels, other non-cohesives, and clays.