FPSO Vessel Integrity Program

Location: UKCS

The FPSO was launched in 1998 and following the installation of the topsides was on location in April 2000. To support field life extension from 2020 to 2026, the client initiated the original Vessel Integrity Program (VIP) in 2007. The VIP comprised two phases:

  • Phase 1 – Unit assessment: detailed analysis to assess the condition of the vessel and detect critical areas.
  • Phase 2: Solutions Analysis - For areas of concern identified in Phase 1 investigations and further analysis were to be developed to determine the best practical, long-lasting solutions.

The VIP had largely remained dormant since 2010 with Phase 2 of the original project only being partially completed.


Scope and Challenges.

Optimus was contracted to review the VIP and develop a Decision Support Package (DSP) to support a go/no-go decision with regards to the revitalisation of the dormant VIP initiative. During this review Optimus located accelerometer and strain gauge data recorded on the vessel as part of the original VIP.

Following recommendations made in the DSP Optimus were contracted to revitalise the FPSO VIP. A staged approach was proposed, comprised of the following stages:

  • Stage 1 – Data Review and initial benchmarking of original hydrodynamic analysis;
  • Stage 2 – Updated structural analyses, both strength and fatigue;
  • Stage 3 – Benchmarking of revitalised analyses against previously recorded vessel behavior.

Recently Optimus has completed an update to the Vessel FPSO fatigue assessments. This work has been undertaken to support a Safety Case update for continued operation beyond the original design life of the asset. The updated fatigue assessments captured changes in the following parameters:

  • Metocean data
  • Loading plan
  • Deadweight
  • Mooring stiffness