Some 44% of the world ship shape FPSO fleet have hulls that are above 30 years of age. All of these are conversions from Oil Tankers that had an initial design life of 25 years.
Continued operation of these vessels will bring increasing challenges to maintain hull integrity as fatigue life and corrosion margins becomes depleted. Several of these vessels were in addition installed without fatigue calculations and some should have been reinforced before installation.
All is not bleak, however, as many of these tankers are in benign environments. As the tankers were designed for worldwide trade, they might be stronger than what is locally required.
Inocean can demonstrate by calculations what loads the vessel is subject to in the applicable area and document if extra margins exist. This could save considerable repairs.
Inocean can use this information to provide input and help design a custom inspection, maintenance and repair scheme to secure continued safe operation of the vessel. This would typically include a list of which structural areas that should be repaired or specially monitored, and suggestions for inspection intervals.
If a risk format is preferred, Inocean can provide a risk ranking of the structural defects with likelihood input from a fatigue analysis.
Inocean, October 18, 2013