-Two×25 te/day water makers. Although most potable water will be bunkered, these units provide distilled water required by some topsides equipment and provide a backup to the main water supply. For the delivery voyage this avoids the need for additional temporary water tanks.
-There are 3 KaMeWa thrusters, located in caissons in the aft thruster maintenance area. These are capable of being withdrawn inside the hull for maintenance. Maintenance access is provided so that all major components can be removed from the Vessel while offshore.
Accommodation/Deckhouse/Bridge. The accommodation is designed for 80 persons of whom 48 will be permanent. The whole of the accommodation block is defined as a temporary safe refuge (TSR). This area provides a safe haven for the crew, in the event of fire or gas release for a minimum of 2 hours.
The accommodation block incorporates the following features;
-Main deck: Workshops, secondary switchroom, laundry, and gym
-Process deck: control room, offices, hospital and laboratory
-1St Deck: Mess (Muster area), galley
-2nd deck: Cabins (43)
-3rd Deck: Helicopter lounge, telecoms equipment room, radio room, navigation bridge
-4th Deck: Emergency Generator, HVAC plant room
-Helideck and parking area
The Navigation Bridge is fully functional to meet regulation requirements for an Ocean going Ship. In addition a Bailey control console and a Simrad control console permits operation of all Vessel and topsides systems from this location. This provides a level of backup to the CCR. A further additional feature is a high resolution ice detection radar.
The Vessel is equipped with 3 Schat Harding, 80 man davit launched lifeboats (TEMPSC). Two boats are located forward at the TSR and the third is located at the aft end of the Vessel on the starboard side. Additionally, some 15 Viking Liferafts are also included, strategically located throughout the installation.
A common control system has been provided for the FPSO. This controls Vessel, Topsides, Turret and subsea equipment. Common hardware and a common approach to software development has resulted in a low maintenance system. The Vessel system has some additional features to allow for the different regulatory requirements. The Vessel control system (VCS) designed by the Newfoundland company Bailey Sea will provide a high level of remote and automatic control. The fire and gas system is common throughout the facility. The Vessel part of this has been designed to be stand alone for the delivery voyage to Canada where it will be combined with the topsides unit. A Vessel Shutdown System (VSD), with a security level approximating to SIL 2 has been provided to provide an extra level of security for cargo and ballast operations.
Forward Machinery Space. The forward machinery space contains two so-called‘key service' ABB generators driven by Wartsile diesel engines and each rated at 6.5 MW. These units are sufficient to self propel the Vessel to Canada from the Korean shipyard. In addition they provide an extra level of redundancy in case of failure of the gas turbines. Being located forward of the turret the chance of these units being compromised by a gas release is negligible.
The two main Sulzer firepumps are Caterpillar driven and are located in separate A60 -rated enclosures on the 20.9 m flat.
A further two KaMeWa thrusters are located in-line in this space. Both are capable of being withdrawn inside the hull for maintenance.
Offshore Vs Shipbuilding Standards
Although FPSOs have been in use round the World for many years they have only been deployed in harsh environments in recent years. Very little operational experience is available. However it is generally agreed that for harsh environments vessel design and fabrication should exceed normal shipbuilding standards. Crucial to the development of the PV150 design by Brown and Root has been the use of a specially formed team of design engineers with experience in both the Offshore and Shipbuilding industries, involving both fixed and floating platforms in the North Sea and in the Far East. This 'Vessel Group' has provided a very necessary interface with topsides designers during the preliminary design, before a shipyard could be selected. This has permitted a high level of common systems to be designed operating between the vessel and topsides.
The objective of a Vessel Group like this to is to retain flexibility in design. FPSO design varies according to the area of deployment, the life of the field and the extent of production plant installed on the vessel.
Interface management is the key to a successful FPSO project. The use of integrated systems may only be practical if one company has overall charge. In this case the best contracting strategy is for the shipyard to be subcontracted to the engineering company. Where there is an interface with process systems it is necessary to use offshore engineering resources to support the shipyard in key areas, such as Control Systems, Electrical design, HVAC design, Loss Control, Fire and Gas systems and Safety studies.
It is important, however, not to over specify or to assume that marine practice must automatically be superseded. A‘fit for purpose' philosophy is required where the shipyard uses its normal practice as far as possible and petrochemical industry standards are used only where they are necessary to ensure the safety, operability or performance of the completed FPSO. Items that require exact definition were specified in detail, Functional Specifications being used for the rest, particularly standard marine equipment.
The Vessel Group had a key role in this process, carrying out the basic design of the FPSO to suit the operator's needs, and representing the shipyard's interests during Concept Design until a yard had been appointed. The group then become shipyard contract managers and interface management team, overseeing the detailed design and build of the vessel and providing co-ordination between the shipyard and the rest of the project.
