Photo: OHT

MacGregor orders Kongsberg Maritime’s pile gripper guidance system for OHT Alfa Lift

MacGregor has placed an order with Kongsberg Maritime for its Pile Gripper Guidance System (PGGS) for the Alfa Lift foundation installation vessel, which China Merchants Heavy Industry (CMHI) is currently building for Offshore Heavy Transport (OHT).

In August, MacGregor announced an EPC contract for the vessel’s the monopile lifting, skidding and transfer system. The company then said the system was an integral part of the installation process employing an upending tool and a motion-compensated gripper frame, with the latter being interfaced with the vessel’s dynamic positioning (DP) and control system in an integrated solution developed jointly with Kongsberg Maritime.

Under the contract just signed by MacGregor and Kongsberg Maritime, MacGregor will deliver a motion-compensated pile gripper frame, while the PGGS will integrate the gripper with other Kongsberg Maritime systems on board Alfa Lift.

A K-Pos dual-redundant DP system will interface with a K-Chief marine automation system and K-Thrust thruster control system, while a K-Bridge integrated navigation system will provide a single, intuitive user interface for the ship’s multiple connected systems, according to Kongsberg Maritime. A full suite of K-Power products will accommodate the main switchboard, generators and drives, while KM’s azimuth and tunnel thrusters will take care of the vessel’s propulsion, steering and positioning thrust.

“Kongsberg Maritime and MacGregor have both been working in close collaboration to develop this new, integrated monopile installation solution, incorporating KM’s most sophisticated, up-to-date automated handling functionality”, Kongsberg Maritime said.

“By removing the need for temporary mooring procedures during installation operations, the solution will enhance safety, productivity and mission consistency, generating substantial savings in time and money for the specialist transport and installation contractor OHT. In time, these positive changes will be reflected in a wider sense when the concept is rolled out across the offshore wind energy market”.

OHT’s Alfa Lift, due to be delivered in early 2021, has already been selected for the transport and installation of monopile foundations and transition pieces at Dogger Bank A and Dogger Bank B wind farms.

The 216.3-metre vessel will be equipped with a 3,000-tonne main crane, a 10,000+ m² “smart” deck that can carry up to 14 XL monopiles per trip, and will be fully submersible to a depth of 14.66 metres.

CMHI, which is constructing Alfa Lift at its facility in Jiangsu under an order it received from OHT in July 2018, cut the first steel on 1 March 2019.

The vessel, designed by OHT in close cooperation with Ulstein Design & Solutions BV, Liebherr and DNV GL, will be capable of installing all types of bottom-fixed offshore wind foundations and will also transport and install topsides and subsea modules, in addition to other heavy cargoes within oil and gas.