Subsea 7 required a positioning system to provide field wide positioning throughout Statoil’s Aasta Hansteen development offshore Norway, located in water depths of 1,200m.
Field Wide Subsea Positioning: Aasta Hansteen Field
Proserv’s NASNet® positioning system was used to provide an advanced multi-user, Long Baseline (LBL) positioning system to simultaneously position unlimited objects with fast updates and no acoustic interference.
With the installation of an array of 17 NASNet® stations with various NASNet® MTrx QC references, all ROV and vessel deployed VTrx systems provided ROV positioning and enabled system management functions to be performed. This ensured that all stations were deployed on average in less than 4.5 hours per unit including calibration, exceeding the clients expectations.
“…we are very satisfied with the attention to detail and quality of the NASNet® LBL array planning, preparations, training and support throughout the course of the project. The positioning performance during all installations and seabed surveys re-enforced our confidence in NASNet® LBL, and the system contributed increased flexibility, simplicity and efficiency to marine operations, ultimately reducing vessel time and cost...”
With a number of ongoing operational campaigns, multiple vessels and operators such as EMAS, Fugro and Subsea 7 have all utilised NASNet® during this project. Tasks undertaken include the installation of foundation and mooring piles, templates, jumpers and general ROV positioning in support of construction and in-field umbilical installation.