Blue Ship Invest has ordered a series of six medium-sized platform supply vessels based on Ulstein’s PX121 design. The first three vessels have been delivered while the other three vessels are set to be delivered in 2013.

Blue Ship Invest initially ordered two vessels from Ulstein in 2010. The company further ordered four more vessels of the same design in June 2012, following the success of the first vessel, Blue Fighter, which was delivered in January 2012. The Blue Fighter is currently chartered to the oil company Apache.

The second vessel, Blue Prosper, was delivered in September 2012 while the third vessel, Blue Power, was delivered in March 2013. The fourth vessel, Blue Thunder, is scheduled for delivery in April 2013.

The first two vessels in the series are chartered to Apache and are managed by Remoy Shipping. The third vessel is managed by Atlantic Offshore. The fourth vessel will also be managed by Atlantic Offshore and will serve Statoil in the Norwegian North Sea offshore Bergen.

Design features and storage capacity of the PX121 PSV

PX121 measures 83.4m in length and has a moulded breadth of 18m. The depth of the vessel to main deck is 8m and the maximum draught is 6.7m.

The vessel features a cargo deck area of 850m² with a deck load capacity of 2,300t and a maximum deadweight capacity of 4,242t.

The vessel features Ulstein X-BOW hull line design. It is equipped with tanks which can store up to 1,474m³ of fuel oil, 1,033m³ of fresh water, 1,676m³ of ballast water, 1,307m³ of liquid mud, 1,307m³ of brine and 259m³ of base oil.

It also features four tanks with a combined capacity of 254m³ to store cement, and four tanks with a combined capacity of 153m³ for storing low flash point liquids (LFL).

Accommodation facilities on board the PX121 platform supply vessels

The vessel has the capacity to accommodate 24 people. The decks feature a floating floor providing low noise and vibration levels.

The accommodation facilities include two state cabins with a day-room and bedroom, eight one-bed cabins, five two-bed cabins, and two two-bed cabins featuring a common day room.

Other facilities include a sick bay, a mess room, a room to accommodate galley, dry provisions, cooler and freezer, and a room which can be interchanged to accommodate pantry, wardroom, laundry and gym.

Deck cranes and winches

The platform supply vessel is equipped with a main knuckle boom shipboard crane with a lifting capacity of 3t and outreach of 18m. The vessel features an anchor windlass / mooring winch with a three drum configuration. It also features two 10t tugger winches and two 10t capstans.

Lifesaving and firefighting systems on the PX121 PSV

Lifesaving equipment and rescue equipment aboard the vessel includes two life rafts with a capacity for 25 people and a man overboard boat (MOB) with a single point davit system of movable type which can be propelled either by a diesel engine or water jet propulsion.

The vessel features a water mist full flooding system for the engine room and a local protection system incorporating a water mist total flooding system and foam system with monitor for LFL cargo tanks.

Navigation and communication systems

The navigation and communication systems of the vessel include an S-band ARPA radar and X-band ARPA radar, an electronic chart display and information system (ECDIS) with two independent stations, a conning system featuring two displays, radio installation based on GMDSS A3 requirements, and two Satcom C systems.

Machinery and propulsion system of the PX121 vessel

The vessel is configured with four main diesel generator engines including two 2,350kW engines and two 994kW engines. It also features an emergency generator with a capacity of 200ekW.

The vessel is propelled by two main azimuth pulling propellers with a capacity of 2,220kW and electric propulsion motors with a capacity of 2,200ekW.

The vessel is also equipped with a forward tunnel thruster with a capacity of 1,050kW and one forward retractable azimuth thruster with a capacity of 880kW.

The vessel is capable of sailing at a maximum speed of 16kt.

Treatment systems onboard the PX121

PX121 features two UV sterilisers, a vacuum sewage toilet plant, a sewage treatment plant, two self-cleaning fuel oil (FO) separators, and a ballast water treatment system with a treatment capacity of 250m³ per hour.