Mammoet has wrapped up the first phase of a challenging upgrade at thyssenkrupp Steel’s oxygen steel plant in Duisburg, Germany. The job? Replacing massive crane girder beams—some weighing as much as 160 tonnes—without bringing the plant’s production to a halt.
To avoid long production downtimes, the project needed meticulous planning months in advance. That’s where Mammoet’s Move3D platform came in. Using 3D engineering, the team could map out every obstacle, simulate lifts, and position cranes in tight spaces—avoiding costly last-minute changes.
The steel beams being swapped out are no small feat. Each one stretches between 30 to 45 metres in length and stands 5 metres high. The replacement was split into two phases, with seven beams handled in the first round.
Two massive mobile cranes from Liebherr—an LTM 1750-9.1 and an LTM 1650-8.1—handled the bulk of the heavy lifting. But for some beams, space was so limited that cranes couldn’t reach.
For those tricky areas, Mammoet engineers designed a clever gantry lifting system. It involved two towers and a set of skid tracks spanning the hall, topped by a beam carrying two strand jacks—devices that can slowly and precisely lift and move heavy loads.
Installing this gantry wasn’t easy. Some parts of the plant couldn’t be taken apart, so Mammoet had to build over and around them. One crane even had to work over a basement, where the floor couldn’t support its weight. The team got creative—using extra-long mats to shift the load to stronger parts of the building.
The first five beams were removed and reinstalled quickly using the mobile cranes and SPMTs (self-propelled modular transporters). But the final two beams in this phase required the full gantry setup, with strand jacks and cranes working in sync.
Each beam was lifted with the jacks, moved across the hall on skid tracks, and handed off—step-by-step—between the cranes. With limited room, the cranes had to telescope their booms in and out mid-lift, while carefully coordinating every move with the jacks.
It was a high-stakes operation that demanded precise timing and flawless teamwork.
René Xyländer, Director of Operations at Mammoet Germany, praised the effort, saying, “The 3D engineering and our custom gantry system were key to staying on schedule.”
With phase one done safely and on time, the team is now preparing for the second round of beam replacements.