Offshore staff
MONACO -- Contractors have become more skilful at managing schedules for large FPSO projects, according to a presentation by Technip today at the Deep Offshore Technology Conference.
During a sustained spell of major delays and cost overruns affecting FPSOs in the 1990s and early 2000s, the industry’s reputation suffered, claimed the authors Brian Roberts and Jacques Vende. Since the mid-2000s, however, planned versus actual schedule performance has improved markedly.
Technip has engineered the topsides loads for four of the larger FPSOs operating off West Africa, ranging from Dalia offshore Angola (28,000 metric tons, or 30,865 tons) to most recently Akpo off Nigeria, which sustains the world’s largest FPSO topsides, at 37,000 metric tons (40,785 tons).
Typically, these huge vessels are around 300 m (984 ft) long, with a beam of 60 m (197 ft), and oil storage capacity of 2 MMbbl. The topsides are split into modules which are lifted onto the completed hull, then hooked up at a quayside before towing of the integrated unit to its offshore location for hook-up and commissioning. The schedule for a project this size can stretch to 46 months.
The authors identified eight main challenges to successful management of these schedules and the large and disparate engineering teams involved, based on Technip’s experiences with Akpo. Among the points noted:
- Endorsement of the project’s front-end engineering design (FEED) is critical, given the very short window during the bid phase for reviewing a large, complex installation with multiple interfaces
- Competent engineering centers are needed to manage the project’s wide-ranging requirements, with a system in place to ensure mutual understanding of different approaches among the often multi-cultural project teams
- Construction of large scale FPSO hull and topsides modules is the domain of world-class yards, but training sessions should still be organized to ensure the designers understand the block fabrication production approach and its constraints
- Managing the interface control between the hull, risers and topsides is a challenge given the variety of contracting parties involved and their differing priorities. An interface matrix should be established at the contract stage, with swift turnaround and despatch of interface documentation to ensure its availability when needed
- Fulfilling the overall project execution schedule demands fast-track procurement of long-lead equipment items, with requisition engineers and inspection coordinators brought into the project at an early stage
- Tight supervision of module weights, which must not exceed the lifting capacity at the integration yard. Increasing topsides weight can also affect the vessel’s stability. Project management should appoint a dedicated weight control engineer and implement a weight control program that interfaces with the 3D model and the materials management system.
11/04/2009
