A look into Mammoet’s reinstallation of Liebherr HLC onboard DEME’s Orion
DEME’s offshore installation giant, Orion, recently had its naming ceremony at the company’s base in Vlissingen, shortly after it arrived from Bremerhaven. The vessel features a 5,000-tonne crane and a unique Motion Compensated Pile Gripper designed to handle the next generation of wind farm components.
In 2020, during the load test at Liebherr’s construction yard in Rostock, the crane collapsed damaging the vessel significantly. However, after a thorough rebuild, Orion arrived in Vlissingen and was deemed ready to perform its scheduled operations following a christening ceremony.
Mammoet lifts the ‘unusual’ components onto Orion
To reach completion, the vessel needed a crane reinstall and heavy lift specialist Mammoet was entrusted with the transport and lifting activities associated with rebuilding the crane. With its first project already scheduled, the top priority was to meet the delivery date for Liebherr’s customer DEME.
The dimensions of the HLC 295000 components were unusual, to say the least: the slewing unit weighs 1,850 tons, the boom is 1,500 tons and 120 metres long, and the A-frame weighs 900 tons and is 70 metres long.
Handling these items required specialist expertise, even by the standards of the heavy lifting industry. With its many engineering nerve centres separate to operational activity and the world’s largest fleet of equipment, Mammoet was able to mobilise the team and equipment to get the job done safely and efficiently.
In fact, to handle these highly specialised items safely, Mammoet needed to deliver around 2,000 tons of material to the site. This included various cranes, transport vehicles, 400 tons of rigging equipment, as well as support and special equipment. The rigging alone for lifting the boom weighed 80 tons.
The plan created by Mammoet’s engineering team was to create a custom transport and lifting concept using Liebherr’s own TCC 78000 rail-mounted heavy-duty crane. The plan would also use two crawler cranes, several mobile cranes and Mammoet’s JS 500 jacking system.
Special rigging schemes were designed and fabricated to meet the specific component requirements. In order to manoeuvre the oversized and heavy components safely across the Liebherr site, the transports were planned with 68 axle line SPMTs.
First, the slewing unit was transported from the pre-assembly site to the crane location. It was lifted and installed onto the Orion in a tandem lift using the TCC 78000 and an LR 11350.
In a second operation, the A-frame was erected via a tandem lift using the TCC 78000 and an LR 1750. The component was transported approximately 800 metres on the hook of the TCC 78000 and lifted to a height of 120 metres, onto the Orion, for installation.
Finally, the boom was lifted onto the Orion in a tandem lift using the TCC 78000 and a LR 1750 to a height of approximately 60 metres and installed. The LR 1750 crawler crane, which had previously been used to tail the A-frame, was moved from the pre-assembly site to the quay within a very short time and reconfigured to “luffing jib mode” for the boom lift.
An eye on the weather
Execution in autumn and winter always brings special challenges for projects of this type. The frequent occurrence of storms was closely monitored by permanently checking and previewing the weather conditions. Thus, even the smallest wind windows could be exploited to safely realise partial activities within the specified time. Even the start of the lifting activities as early as 4 a.m. in the morning posed no obstacle.
Gernot Öder, manager Crane and Transport Projects, Engineering & Project Management at Mammoet Germany, said, “The experienced team reacted flexibly to the constantly changing requirements in operational business and adapted the engineering and lifting plans just in time. Through constant optimisation, the ambitious schedule could even be shortened in some cases.
The restored crane’s first project will be Arcadis Ost in the Baltic Sea and further deployments are already planned.