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solutions that could curb these in corrosion and failure mechanisms problems and help keep FPSOs and which will help to prevent some moor- other ? oaters on station?

ing line failures in the future.

Bruce Crager: Peter Lovie: The industry has sig- Mooring line failures ni? cant experience with mooring systems are not new, and not just with FPSOs. for both offshore rigs and ? oating produc- Hurricanes Katrina and Rita in 2005 tion units, including FPSOs. There are caused multiple semisubmersible drill- only ? ve dynamically-positioned FPSOs ing units to break loose and drift in the in the world so the large majority are Gulf. It was these mooring line failures moored. The mooring system normally that led to the nightmares in the minds remains in place during the life of the of knowledgeable operators’ that one of ? eld. It is possible to inspect mooring these MODUs would bang into an FPSO systems in-situ using divers and ROVs loaded with oil during the hurricane, and the industry has the capability to causing a horrendous oil spill of Valdez replace speci? c components such as proportions. Hence, the 2006 scramble chain, wire rope and synthetic rope sec- to make FPSOs disconnectable for the tions. However, more work is needed to US Gulf, and the OTC sessions and improve the longevity of these compo- panels on this theme in 2007.

nents in long life ? elds, particularly in Around 2008, the ability to inspect harsh environments. mooring lines on location became much more doable. In 2014, these mooring

As discussed in last line failures are widely recognized as a

Arjan Voogt: year’s forum, there are many different problem by operators, underwriters and reasons why mooring lines break. In the regulators, and all working to do some- end, an anchor chain is nothing stronger thing about it. The underwriters see a than its weakest link. Mooring systems loss rate of 10 times more with moor- are designed with this in mind and can ing systems than with other offshore maintain station with one line down. The underwritings. broken line does need to be replaced, Their Floating Unit Mooring though, which often takes many months Assessment (FUMA) initiative in its of planning and preparations. Anticipat- 21 July 2014 presentation says that in ing line failures in advance and design- 2001-2011 there were 23 documented ing the mooring system for a potential mooring failures, eight of which were line replacement, together with life systems failures (multiple line dam- monitoring of the lines will help keep age and drifting), all based on OTC

FPSO’s on station. This years’ mooring Paper 24025. Their “Moored Floating special session (at Global FPSO Forum) Unit Portfolio” cites 112 incidents in will compare competing system to moni- six years with a total of $2.86billion in tor the lines. In addition to this, FPSO claims. operators will present ongoing research “Houston we have a problem.” of Mexico. This could be why Douglas- Petrobras operates numerous ? elds in

Westwood found that FPSOs represent the country’s presalt that account for “the largest segment of the market both the bulk of the region’s FPSO installa- in numbers (94 installations) and fore- tions. Despite the national’s high-pro? le cast CAPEX (80%) over the 2013-2017 troubles, including signi? cant ? nan- period. FPSSs account for the second cial cutbacks and a scandal related to largest segment of CAPEX (10%), fol- contractors, Douglas-Westwood expects lowed by TLPs, then spars.” that it will continue its hold on the

The ? rm, which analyzed around region. Beyond Latin America, it noted, 1000 FPS projects for the report, found “Asia is the next most important region that Latin America accounted for 29% in numerical terms (24 installations, but of the forecast installations and 37% Africa is so in terms of forecast CAPEX of the projected CAPEX, partially due ($18.2 billion).” • to the fact that Brazilian state-owned –Sarah Parker Musarra oedigital.com September 2014 | OE 33 026_0914_FPSO1_Roundtable.indd 33 8/21/14 2:31 PM