Subsea Construction Vessel Contract Goes to Norway's Ulstein

Ulsein has signed a contract for delivery of a high capacity subsea construction vessel of the SX121 design to GC Rieber Shipping, with an option for a second vessel

The newbuilding will be delivered in the first quarter of 2014 and has a value of approximately NOK 800 million.

The ship of SX121 design is to be equipped with a dynamic positioning system of the highest class (DP3).
The subsea construction vessel is 130 metres long and 25 metres wide with a top speed of 14.5 knots. She will be equipped with a large active heave compensated offshore crane with 250 ton capacity at 14 metres outreach and with the winch placed below deck. The crane will mainly be used for lifting and lowering heavy equipment from and to the sea bottom.



The new vessel will carry two ROVs; one is to be launched from the starboard side and the other through a moonpool. 
The ship has a large cargo deck for OCV work. She will have diesel electric propulsion and three main azimuth thrusters. The vessel can accommodate 130 persons and will be constructed in accordance with the latest international environmental regulations.


In addition the ship will be prepared for a VLS tower (vertical lay system) and a 2,500 ton rotating carousel below deck, to be used for future pipe laying operations. For that reason, it will also be equipped with two moonpools, one for future VLS and one for launching the ROV.



Vocabulary:



Moonpool: 
An opening of the hull, giving access to the water below. Through the opening, tools and instruments can be lifted and lowered into the sea.



Active heave compensated: 
By the use of hydraulics, heave compensators reduce the effect of vertical ship heave, with the result that the vessel does not require completely calm seas to perform construction work



ROV: 
Remotely operated vehicle: An underwater robot linked to the vessel by an umbilical cable, which can observe and send data, film, photos and signals from the sea bed.