SX121

The SX121 platform is a well-proven, robust, and flexible vessel designed for global subsea operations. It can be tailored to marine activities, such as Offshore construction, SURF, Cable lay, and Diving operations. The vessel's ULSTEIN X-BOW ® hull design is optimized for low fuel consumption and is available with battery and alternative fuel options, focusing on sustainability and energy source flexibility.

Vessel Type

Subsea

Ulstein Design & Solutions AS

Primary Specifications

Length

120-140 m

Beam

25 m

Dead weight

9,300-10,800 t

Draught (max)

7.6 m

Speed (max)

14 kn

Accommodation

100-130 POB

Deck area

1,400-1,850 sqm

Crane capacity

250-400 t

Additional Data

LARS for WROV

2 x 12 t

SWL ROV Handling systems (space reserved only)

Dynamic Positioning

DP2 or DP3

Moon pool

8.4 x 8.4 m

Note: Subject to selected variant configuration

Turning visions into reality

The SX121 is a versatile and sophisticated workhorse for various offshore operations. We can tailor our designs to match your exact requirements.

SX121 – Subsea Vessel

With its advanced design and engineering, the SX121 platform ensures safe and efficient subsea operations. Featuring our innovative X-BOW® designs, this vessel delivers exceptional performance and adaptability for demanding marine activities.

Fuel efficiency:: The X-BOW® hull design reduces wave resistance, ensuring smoother and more fuel-efficient voyages.
Enhanced stability:: The X-BOW® offers a safer and more comfortable setting for the crew by minimising slamming and vibrations.
Sustainable design:: The vessel is available with battery and alternative fuel options, focusing on sustainability and energy source flexibility.
Continuous operation:: The design allows for continuous operation even in harsh conditions, ensuring your projects stay on schedule.

Alternative use of the SX121 platform

SX121: Large sized Diving support vessel (DSV)
Read more
SX121 Power Export CLV: A modular and flexible platform, designed for export power cable laying but can be adapted to inter-array operations. Cable tank and carousel either on deck or below deck if requested. A high deadweight capacity up to 9,000 t enables cable capacities up to 6,500 t. Comes with a bollard pull up to 90 t for ploughing.
Read more
SX121 Power Inter-array CLV: This is a modular and flexible platform designed for inter-array operations. The vessel is fitted with two cable tanks and carousels below deck. A high deadweight capacity of up to 8,200 t enables cable capacities of up to 6,000 t. It also comes with a bollard pull of up to 90 t for ploughing.
Read more

Proven design - subsea references

Decades of building state-of-the-art vessels for demanding marine operations have given us a knowledge base and experience guaranteeing the highest standards of quality, execution and delivery.

Shipbuilding worldwide

In addition to Ulstein's yard in Norway, we work with partner yards worldwide. Contact us if you have a specific yard in mind for your next project and would like us to assist.