MSG Krandienst loaded the drive system for a tunnel boring machine from a heavy goods vehicle to a ship at the Rhine port of Kehl on behalf of Herrenknecht AG.
The weight of 200 tonnes meant the company relied on the lifting power of a Demag duo consisting of two Demag all terrain cranes - a 500 tonne capacity AC 500-8 and a 700 tonne AC 700-9.
As the MSG team arrived at the Rhine port of Kehl with the two cranes, three trucks, and an escort vehicle. Four MSG team members spent two hours per crane to get their machines ready for the lift, something that was mainly made possible by the ease of setup of the cranes.
To lift the 200 tonne load, the MSG team determined the best configuration was to have a boom length of 25.5 metres and a counterweight of 100 tonnes on the AC 700-9. The star-shaped outriggers, extended to a length of 12 metres, provided the necessary stability.
For the AC 500-8, the team used a boom length of 24 m and a counterweight of 140 tonnes and extended the outriggers to 9.6 m. The AC 500-8 picked up the tunnel boring machine drive system with nine-part reeving at the hook.
What followed was the “fine art” of lifting: Working together, the two cranes lifted the tunnel boring machine drive system bit by bit to a height of 3 m.
Reinhard Schmitt, the AC 700-9 crane operator, said, “It all came down to how our two crane operators were able to work together with utmost accuracy. They had to stay perfectly co-ordinated in order to ensure that the weight would remain properly distributed between both cranes at all times.”
This made it possible to use a working radius of 14 m to lift the drive system off the heavy goods vehicle, move it over the ship, and then put it down there.