X-ray laser shoots at a depth of at least six meters

Depending on the nature of the landscape, the X-ray laser tunnel is between 38 meters and 6 meters deep. When the laser "shoots", X-rays are generated, well shielded underground. The openings in the shaft buildings, through which large components are inserted, are therefore sealed with heavy concrete slabs during operation. At the tunnel entrance in Hamburg-Bahrenfeld, two double-girder bridge cranes, each with a lifting capacity of 20 tons, are used for this purpose. At 20.8 meters, they span the entire entrance hall and can also lift sensitive and heavy equipment synchronously and transport it into the access shaft. Another single-girder overhead crane is specially designed to lift pumps from the accelerator tunnel for maintenance.

Smart features for safe and sensitive lifting

"The sensitivity of our cranes was particularly important for this project," explains Niclas Maassen from Konecranes in Hamburg. "Extremely slow and jerk-free travel was the main requirement." To enable the safe transportation of sensitive equipment, Konecranes uses frequency inverters. This allows the lifting speed of the large crane systems at the tunnel entrance to be infinitely adjusted from 0.5 to 9 m/min. The frequency inverter automatically monitors the lifting speed and thus ensures smooth operation. The trolley and crane travel speeds can also be infinitely adjusted - from 0.5 to 20 m/min and 10 to 40 m/min. The high-quality freight must not swing back and forth in the access shaft. "In addition to the inverters, load sway damping is also used. This smart feature automatically controls the acceleration and deceleration of the bridge and trolley," says Maassen. This prevents swaying in the long shaft. To enable the two double-girder bridge cranes at the front tunnel entrance to work together even in confined spaces, their drums for the long hoist cables are rotated so that they are parallel to the girder. "With such a large lifting height, you need equally long cables. By rotating the drums, we enable synchronous operation of the two large cranes even in a small space," says Niclas Maassen. In tandem operation, one crane operator steers both cranes simultaneously by radio remote control - the movements are automatically synchronized and no longer have to be coordinated by calling out.

Crane systems for every task around the X-ray laser

With a length of 3.4 kilometers, one access shaft is not enough. Four maintenance access points are therefore distributed at regular intervals along the tunnel. Concrete slabs also have to be lifted onto the shaft openings at these access points and high-quality components transported. For these tasks, Konecranes installed a total of four double-girder bridge cranes, each with two trolleys and a lifting capacity of two times 10 tons. They each have a span of 12 meters and a lifting height of up to 21 meters and are also equipped with frequency inverters and load-sway damping. In the experimental hall at the end of the tunnel system, a double-girder overhead crane with a span of 11 meters lifts equipment weighing up to 20 tons from the truck loading zone into the underground hall. In the vacuum laboratory above the hall, a double-girder overhead crane with a lifting capacity of 5 tons is used to transport particularly sensitive laboratory equipment - without jolting or swinging. "Our crane systems move a lot at the European XFEL, from large concrete slabs to expensive components," explains Niclas Maassen. "For smaller transport tasks, we have also equipped the European XFEL research center with wall-mounted slewing cranes and light cranes for loads from 500 kilograms to 2 tons." "The Konecranes team has already supported other large research centers and therefore knows our requirements inside out," says Süleyman Arslan, hall engineer at the European XFEL. "The cranes at the European XFEL have to work reliably and be easy to control. We attach great importance to long-term and sustainable performance."