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prospect since FPSOs, unlike tankers, are not constrained by maximum draughts,

so the typical 2:l ratio can be optimised. This helps structural design and

seakeeping by increasing freeboard whilst permitting greater bow submergence to

reduce slamming.

With regard to the issue of the double hull and the double bottom hull

design, the former has become the norm for FPSOs, whilst there is little

justification at present to impose a double bottom on a statically moored FPSO. It

has become common practice to arrange ballast tanks outboard of the central cargo

tanks. The ballast capacity depends on the range of operating draughts due to

seakeeping requirements and offloading.

4.2.3 Example FPSO Design
Consider two different design options:

New build Aframax tanker, modified to FPSO requirements (fig. 6.2).
New build Barge, configured to FPSO requirements (fig. 6.3).

Figure 6.2 – New build Aframax Tanker, 800,000 bbl storage

Figure 6.3 – New build Aker Tentech Barge, 800,000 bbl storage

The tanker requirements include the following systems:

1. Cargo Oil Storage
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