The Multi Purpose Floater (MPF) is a large tanker hull specially designed to be outfitted as a
deepwater drilling unit with production capability, a pure deepwater floating production, storage and offloading vessel (FPSO) or an FPSO with well intervention equipment. The MPF-1000 has 1 million bbl of oil storage capacity and is equipped with two moon pools. A larger version MPF-2000 could accommodate 2 million bbl of storage capacity for larger development projects.

The MPF-01 (Multi Purpose Floater) is the first of the MFP 1000 Class of vessels to be built. It

Figure 1. MPF 01 in drilling/well testing/early production mode. (Image courtesy of MPF Corp Ltd.)
is now under construction in China. It will be outfitted as a fully competent, heavy-duty deepwater drill ship that also has the capacity to perform extended well testing or production operations on a discovery or appraisal well while simultaneously drilling an additional well. There is sufficient segregated ballast capacity to maintain the vessel at constant drilling draft as crude oil is taken onboard during extended well test or production operations. The MPF-01 may therefore also be used for early production, or even more extended production, while simultaneously continuing drilling or well intervention operations.

Extended well tests while drilling
The need for such a vessel is readily apparent in light of past experiences with deepwater development projects based solely on the interpretation of logs, cores, seismic maps and sometimes short-term production tests with associated pressure transient analysis. These analyses do not always provide sufficient data to fully assess the reservoir characteristics and potential. As a result, some field developments have turned out well, but others have been seriously over-designed or under-designed with regards to expensive wells and permanent production and transportation facilities. Either alternative is very costly with some fields never reaching design throughput and being abandoned long before recovery of the capital outlay and others potentially having much higher productivity than the facility could handle. The ability to perform extended production tests with pressure transient analysis of several months, or more, will result in vastly improved reservoir data and help to optimize development well and facility design.

The extended well tests could easily be followed by an early production phase using the MPF’s capability for simultaneous drilling and production. One or two wells could be put on production while additional wells are being drilled. The produced oil would be taken ashore by shuttle tankers. Depending upon the production rate and gas to oil ratio, the dynamically positioned vessel can be arranged to burn produced gas for power generation and avoid flaring or re-injection of gas in remote fields.

By effectively accelerating the exploitation of a field, cash flow is also brought forward. In most cases this would improve the economics of a field development and significantly reduce the maximum cash outlay in a specific field development.

In the event the MPF were used for early production, or field development, it would have several additional advantages. When the field is depleted, the abandonment costs would be minimized and the asset would be reusable on a subsequent field. Also, the MPF could be demobilized fairly quickly in the event of political unrest, or other threats, if necessary. In severe weather locations, the MPF could disconnect to minimize hurricane or cyclone damage, and then be redeployed quickly to minimize the lengthy downtime which could be associated with repairing damaged permanent facilities.

Robust design
The basic design of the MPF 1000 was developed from 1995 onwards and verified in a joint industry project in 2002, called “Demo 2000,” funded by BP Norge, Shell Technology Norway, Norsk Hydro, Statoil and Ocean Development Corp. The technical feasibility was studied and then validated by dynamic model testing at Marintec. The study also verified the improved economic results using examples from both the North Sea and a field west of Africa.
The MPF-01 is currently being built by MPF Corp. Ltd. Project management and rig operations will be undertaken by OPT-MPF Operating Company LLC out of Houston. Expected delivery time is second or third quarter 2009 dependent on extent of preparation for production mode.

The vessel is a simple, double-hull tanker design with two centerline longitudinal bulkheads and three cargo tanks abreast resulting in superior structural integrity and reduced building cost. It will have the same fair, bow-like configuration at both ends to permit “heading” into the prevailing seas with minimum vessel rotation. This will allow the vessel to maintain station by dynamic positioning while having both drilling and production risers deployed through the forward and after moon pools respectively. All of the drilling, power generation and well testing equipment will be modularized and mounted above the main deck, which will also result in cost savings. There is ample deck space aft for well test equipment or larger production facilities.

Unique feature set
The uniqueness of the MPF design is the ability to drill and produce simultaneously. This ability will allow for extended well testing and production operations while drilling additional wells with the huge benefits described above. The following items summarize the design features that make this possible:
• Dual moonpools spaced to avoid riser clashing in design environments.
• The aft moonpool is designed to accept a disconnectable turret if required.
• Vertical access and hoisting capacity at each moonpool.
• Symmetrical hull configuration to permit “weathervaning,” or power assisted heading adjustment if required, into prevailing seas with less than 90° rotation to avoid riser clashing.
• Large deck area and segregation of topsides facilities, with quarters, power and drilling modules forward to amidship and ample space to accommodate test and production equipment aft.
• Space aft to mount gas turbine generators to use produced gas as fuel.
• Large crude storage capacity.
• Large capacity segregated ballast to allow maintenance of constant draft during simultaneous drilling and testing and production operations.
• Ability to shut down quickly, with no pollution consequences, and move in the event of an approaching hurricane.

An additional feature of the MPF-01 is the utilization of special steel in the vessel which will allow continuous operations in 22°F (-30°C) temperatures, without the steel embrittlement problems that can be associated with cold weather operations. As such the vessel could be utilized in frigid locations such as the Barents Sea or Sakhalin Islands regions.

The main particulars of the rig are given in the table on this page.

The vessel would be capable of staying on location for longer-term production, with the addition of shuttle vessel transfer gear, but its value for deepwater drilling and extended well testing may result in an operator choosing to substitute a purpose built FPSO for that function at the point in time where additional drilling is required. A subsequent MPF designed and built as an FPSO equipped for well intervention work would be an ideal candidate for such an application.

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