A platform supply vessel of the proven PX121 design. ULSTEIN provided a comprehensive design & equipment package that includes basic design and engineering, all major equipment, site support/construction consultancy and commissioning.

Vessel type

Platform supply



Built by

ROC, China



Designed by

Ulstein Design & Solutions AS

Ordered by

ITG Group

IMO Number


Principal dimensions

83.4 m
18 m
Dead weight:
Approx.4,000 tonnes
Draught (max):
6.7 m
Speed (max):
14.5 kn
30 POB
Deck area:
840 sqm

Note: Subject to selected variant configuration


Fuel oil (cargo and domestic):
1,475 sqm
Fresh water (cargo and domestic):
1,055 sqm
Water ballast/drillwater:
1,620 sqm
1,295 sqm
1,295 sqm
505 sqm


  • DNV1A1, Offshore Service Vessel, SF, E0, DYNPOS-AUTR, CLEAN DESIGN, NAUTOSV( A), COMF-V(3), LFL*, Fire Fighter I, OILREC, BIS

Ship history

2023, 26 June: Two Platform Supply Vessels of Ulstein design delivered

On 26 June, two Ulstein-designed vessels of the proven ULSTEIN PX121 design, built at ROC China, were successfully delivered to their new owner. The sister ships have been named Larga and Aprion, respectively. The delivery of these two vessels marks the successful completion of all 18 PX121 ships built in China.

The two PX121 vessels at ROC were contracted in 2013 for the ITG Group, with Ulstein providing design and equipment packages for the project. The ships were constructed to European standards, but their delivery was impacted due to challenging market conditions. Throughout this period, the shipyard, owner, and Ulstein have worked closely together to maintain the vessels' performance and promote them in the international market. Ulstein Electrical Technology in Ningbo has also provided restart services to prepare the ships for delivery.

Ulstein representatives at the delivery ceremony.
Ulstein representatives at the delivery ceremony.

John Ren, Vice President of ROC, shared his thoughts on the project:

"It has been both a challenging and rewarding journey leading up to today, and we are very happy to see our vessels ready for work. We always believed that their innovative design and high-class finishing would lead to a bright future. The market has proven that the PX121 vessels remain highly competitive among their peers, even after ten years. We are glad to have chosen strong partners in the industry, such as ITG, Ulstein, and DNV. We extend our heartfelt thanks for their professionalism, dedication, and support to our company, and we hope to continue our cooperation with more projects together."

The PX121 design has been the most popular of all the platform supply vessel (PSV) designs from Ulstein due to the competitive combination of fuel-efficiency and cargo capacities/deadweight. This translates to a performance level that is usually expected from larger PSVs, but at a medium-sized PSV cost - delivering excellent value-for-money for the owner and operator.