The Semper Gallery, built in 1854, has been undergoing a two-stage complete renovation process since 2013. As well as commissioning Krandienst Kunze e.K. as a general contractor for all crane services, the state-owned company Sächsische Immobilien- und Baumanagement also commissioned AGS Montagen, who took on the replacement of the windows.

The thoroughfare to the Semper Gallery was only a few centimetres wider than the mobile construction crane itself. Once on position, the MK unfolded by a simple touch of a button – at a 30° luffed jib position to a hook height of over 50m.

The individual glass components were safely put into place with the aid of a special glass manipulator attached to the hook of the crane. It was above all else the Micromove fine positioning mode of the Liebherr mobile construction crane that proved to be of invaluable support. Using this mode, the window panes could be placed with millimetre precision, conveniently via remote control.

Remote control operation of the crane was especially important to Ray Bienert, installation team leader at AGS Montagen. In contrast to other lifting solutions, the crane operator was able to stand directly next to the assembly team and was therefore able to clearly observe the pick and set points of the glass panes. At approximately 1.2m x 0.7m in size and weighing 45kg, the glass elements were comparatively small. Nevertheless, absolute attention was called for. “By the second pane we were already working as an established team, the crane operator and us,” said Bienert. “But the speed with which we were able to work was also fantastic. It takes twice as long with other crane systems. We enjoy working with mobile cranes like the MK.” After one and a half hours, all glass panels had been replaced.