When modifications to a large crane system at the ArcelorMittal steelworks in Eisenhüttenstadt were required, crane rental contractor H.J. Nolte Auto-Krane based in Hanover travelled to the German-Polish border region with two Liebherr LG 1750 cranes.
These powerful lattice boom mobile cranes had to hoist a gantry crane to enable a second gantry crane to be rolled past underneath it. The total gross load case for the tandem hoist was 620 tonnes.
As part of an upgrade at the converter steelworks operated by steel manufacturer ArcelorMittal in Eisenhüttenstadt, a heavyweight modification had to be completed to a large gantry crane system. The position of two cranes for transporting so-called ladles, giant containers for annealing pig iron, had to be swapped as a result of the fact that they had suffered different levels of wear.
Jürgen Peters, who planned the job for Nolte Auto-Krane at the steelworks, took two of the three large Liebherr LG 1750 lattice boom mobile cranes from the company’s fleet to handle the hoisting work. The cranes were each set up with a 70 metre main boom and derrick boom, equipped with 460 and 470 tonnes of ballast and positioned on either side of the crane track, which was around 30 metres off the floor. The operator console and trolley system for the gantry crane had to be removed before the tandem hoist could be tackled. “The preparations on the gantry crane required a great deal more time than we thought,” says Peters, “but we nevertheless managed to complete the work during the scheduled converter downtime.”
Changing positions for a longer service life
The two red lattice boom craned were not able to hoist the gantry crane out of the rails and lift it around ten metres into the air until around midnight, several hours later than planned. After the second crane had been moved under the load, the two crane operators from Nolte had to lower the load carefully onto the crane rails. Changing the positions of the two gantry cranes will ensure that the whole system has a longer service life. The crane which has previously been exposed to higher loads will be exposed to lower stresses in its future position, and vice versa.
ArcelorMittal manufactures high quality flat steel bars in Eisenhüttenstadt for the automotive and household appliances industries. The Brandenburg steelworks currently employs around 2700 people. The ironworks and the neighbouring town for the workforce were originally founded in 1950 with the name Eisenhüttenkombinat Ost.