This paper describes the fabrication and installation of the offshore facilities for the Nansen and Boomvang projects. The paper will review the benefits realized from building and installing two nearly identical facilities on an aggressive project schedule. We will describe the fabrication of the hulls at Mäntyluoto Works in Pori, Finland and the decks at J. Ray McDermott in Morgan City, Louisiana. The offshore program will be detailed from the mooring pile installation through the uprighting of the hulls and setting of the topsides. The team solutions to challenges associated with the coordination of fabrication and installation activities and schedules will be described.
Kerr-McGee Oil & Gas Corporation and partners Ocean Energy, Inc. and Enterprise Oil Gulf of Mexico, Inc. are developing the Nansen and Boomvang fields concurrently. Both of these fields will be produced through truss spar platforms. Schedule and configuration similarities enabled the project team to benefit from many synergies in the fabrication and installation of the production facilities. The aggressive project schedule to first oil required that fabrication and engineering proceed simultaneously. Interface management and communication between engineering, fabrication, and installation teams was essential to achieve the project schedule.
The Nansen and Boomvang production facility fabrication and installation was contracted to Spars International, Inc. OTC Paper 14089 (Thibodeaux et. al.), describes the contracting philosophy for the project in Reference 1.
Kerr-McGee and partners initiated the development engineering and concept selection process in the third quarter of 1999. The Nansen project was sanctioned in March of 2000 with first steel cut in May. The hull fabrication continued until July of 2001 when the hull was transported to the US gulf coast. The topsides fabrication commenced with first steel cut in July 2000 and continued until October 2001. The installation activities began in late July 2001 and concluded in early December. A schedule showing the installation sequence is given in Figure 1.
The Boomvang project was sanctioned in July 2000. Hull fabrication ran from the same month until sail-away in October 2001. The topsides fabrication occurred from August 2000 until December 2001. The Boomvang installation activities were interwoven with the Nansen project activities. Boomvang foundation installation commenced in August 2001, as soon as the Nansen piles and moorings were in. The Boomvang hull was installed in December 2001, and the topsides are scheduled for installation in February 2002.
The project success was accomplished through the dedicated efforts of team members from many organizations. Spars International performed the configuration engineering and interface management. CSO Aker Rauma Offshore (CARO) managed the hull detailed design and fabrication. P. I. Rauma performed detailed hull engineering and Mäntyluoto Works fabricated the hulls. J. Ray McDermott (JRMF) fabricated the topsides. J. Ray McDermott Marine (JRMM) was responsible for the facility installations.
