Norway based Offshore Heavy Transport (OHT) is set to enter the offshore renewables and installation market with a new heavy lift transport and installation vessel designed by Ulstein.
This customised Ulstein Alfa Lift design has been developed by Dutch design company Ulstein Design & Solutions BV (UDSBV) in close cooperation with OHT. The first vessel (with options for up to another three units) will be constructed by China Merchant Heavy Industry (CMHI) and available for construction and installation activities from early 2021.
Heavy Lift Crane Operations with the Main Deck Submerged
What makes this dynamically-positioned, 48,000 DWT vessel exceptional, is the ability to perform heavy lift crane operations with the main deck submerged. The patent-pending design combines the benefits of a semi-submersible transport vessel with a large, 3000 mt lifting capacity main crane from Liebherr.
The vessel’s capabilities match the future requirements of the offshore wind industry, allowing it to transport and install up to ten 1500 t ultra-large jacket foundations or eleven 2000 t XXL monopiles plus transition pieces for the largest anticipated Wind Turbine Generators.
Alfa Lift
'We started the development of the Ulstein Alfa Lift idea back in 2015 with the driver to increase the safety of submerged operations and at the same time increasing the operability window for subsea installations using a crane,’ says Edwin van Leeuwen, managing director at UDSBV.
Vessel Particulars
- Loa: 216.3 m
- Lpp: 204.3 m
- Beam (moulded): 56.0 m
- Depth (main deck): 12.6 m
- Draught (design): 8.0 m
- Draught (submerged max.): 27.6 m
- Service speed: 13 kn
- Installed power: 4 x 6875 kW
- Propulsion thrusters: 3 x 5500 kW
- Retractable thruster: 1 x 3000 kW
- Tunnel thrusters (fwd): 3 x 3000 kW
- Positioning system: DP 2
- Class: DNV GL
- Deck strength: 30 t/m2
- Complement: 100 persons
