Norway based Offshore Heavy Transport (OHT) is set to enter the offshore renewables and installation market with a unique new heavy lift transport and installation vessel, a customised ULSTEIN Alfa Lift design developed by Dutch design company Ulstein Design & Solutions BV (UDSBV) in close cooperation with OHT. The first vessel (with options for up to another 3 units) will be constructed by China Merchant Heavy Industry (CMHI) and available for construction and installation activities from early 2021.
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, 3,000 mt lifting capacity main crane from Liebherr.
The vessel’s capabilities match the future requirements of the offshore wind industry, allowing her to transport and install upto 10 x 1,500t ultra-large jacket foundations or 11 x 2,000t XXL monopiles plus transition pieces for the largest anticipated Wind Turbine Generators.
’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 Ulstein Design & Solutions BV.
‘It is great to work with such capable people. When we approached Ulstein with our intended strategy to enter the offshore renewables market and the idea of adding crane capacity to a semi-submersible heavy lift transport vessel, UDSBV presented their Alfa Lift solution on the spot’, mentions Torgeir E. Ramstad, CEO at OHT. ‘That was a direct ‘hit’, as it allows us to enter the installation market, at the same time expanding on our capabilities in OHT’s core market.’
‘It is an honour that OHT entrusted us to design their first offshore installation vessel, which we feel is a recognition of our ability to create new, cost effective vessel solutions’, continues Van Leeuwen. ‘Creating a new design with this combination of functionalities has its own, specific challenges, but it is rewarding that 2 years after signing our mutual NDA, OHT has contracted a shipyard to build this new vessel type. The success of the project comes for account of the close and fruitful cooperation between OHT’s team and our design team, led by Dolf Manschot.’
Main dimensions of the vessel are:
|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 6,875 kW|
|Propulsion thrusters||3 x 5,500 kW||Retractable thruster||1 x 3,000 kW|
|Tunnel thrusters (fwd)||3 x 3,000 kW||Positioning system||DP 2|
|Class||DNV-GL||Deck strength||30 t/m2|
Ulstein Design & Solutions B.V. specializes in the design and development of vessels for the offshore renewable market and oil and gas industry, fully customizing them to client specific requirements. We have a solid reputation for refreshing and innovative ship designs and provide customers with best-in-class solutions, combining a pragmatic design approach with extensive naval architectural skills. Besides newbuild designs, Ulstein Design & Solutions is actively involved in consultancy and feasibility studies for upgrading vessels or supporting salvage operations. We support clients with our knowledge of hybrid power systems, stability, SPS and DP requirements and using in-house FEA and CFD departments, result in CAPEX friendly ships.
ULSTEIN is a family-owned company with 560 employees, headquartered in Ulsteinvik, Norway. ULSTEIN delivers products and services within ship design, shipbuilding and equipment packages to the international market within offshore, expedition cruise and offshore wind segments. For 100 years, ULSTEIN has been associated with innovation and quality in design and delivery, meeting the demanding marine challenges by embracing change and identifying opportunities. ULSTEIN’s vision is to create tomorrow’s solutions for sustainable marine and offshore operations.