Vito Project: Host Construction and Commissioning

Abstract In 2009, the Vito field was discovered in more than 1,200 m of water approximately 240 km offshore from New Orleans, Louisiana in the Gulf of Mexico (GoM). The project produces from reservoirs nearly 9,100 m below sea level. This paper provides the efficiencies in constructing the Vito FPS at a single fabrication yard, commissioning, and preparation for offshore installation. This paper is part of a Vito Project series at OTC 2023 and the other papers are listed in the references. The Vito Floating Production System (FPS) has a Lightship of 21,500 mt, Topside Lift Weight of 8,700 mt, and is 86 m Length × 86 m Width overall. Vito FPS fabrication at a single fabrication site included Hull Fabrication, Topside Fabrication, Living Quarters (LQ) Fabrication, Integration, and a majority of the Commissioning Scope. Key drivers to be successful at a single site included demonstratable safe execution, offshore fabrication quality capability, fabrication yard throughput availability, achievable integration execution plan, and competitive pricing. Following a transport to a readiness site adjacent to the Gulf of Mexico, four months of continued commissioning and preparation for offshore installation included the key activities of installation of the Temporary Living Quarters, riser and umbilical installation winches, tow-out and station-keeping rigging; de-preservation, final commissioning and verification of operability of key systems; aviation readiness and safety equipment verification; and final USCG inspections to obtain the Authorization to Proceed Offshore. The efficiencies identified and realized at the single fabrication site during the Vito FPS fabrication execution included focused safety at a single site, simplified quality weld procedures, single interface for detail engineering, simplified procurement delivery plan for Company Provided Items (CPI), efficient preservation strategy, single regulatory interface site, enhanced site team efficiencies in engineering and inspection, and simplified contracting at a single source. The readiness site integrated members of the Construction, Commissioning and Operation teams utilizing a single location to quickly mobilize various vendor teams for a final preparation for offshore installation without the constraints of remote offshore work. A key enabler to select the fabricator was their ability to complete a majority of the commissioning scope on the ground prior to integration of the complete Topside and Hull based on the single lift capability of the new 2 × 15,000 mt gantry cranes, which further increased the efficiency at the single fabrication site. 85% of the commissioning was completed by a Commissioning Management Contractor (CMC) prior to integration including load testing and dynamic commissioning of all the major rotating equipment.