New crane conveying system from Liebherr

Liebherr has developed the KFA Crane Conveying System to handle the special hoisting tasks encountered in tunnel projects.

Crane conveying systems are cranes required to carry out the horizontal transport of loads in one direction only, in a similar way to stationary gantry crane. This new system was deverloped for the Machine Technology Service Centre in Germany, operated by Bilfinger Berger AG.

Once the tests had been successfully concluded, the newly developed crane conveying system was demonstrated in Malmö, Sweden and Vancouver, Canada. They involved lifting the material excavated from tunnel boring.

It is made up in modular format from the standard crane from tower, jib, hoisting winch and switchgear cabinet components. Only the system's jibs need to be slightly modified. This cuts down on costs, says Liebherr.

There is a central control unit for each hook, similar to the control system of a tower crane, located in a climate-controlled switching station. The electronic monitor system (EMS) displays all the relevant data, including hook position, load, and speed. The programmable logic control means someoperational sequences can be at least partly automated.

Additionally, the Liebherr Crane Conveying System also provides the possibility of linking together both trolleys mechanically and both programmable logic controls, which means that the working load can be doubled. This type of hoisting is called for when lowering prefabricated components into a tunnel, for example. Parts can be lowered down to a depth of 370 m, and excavated material can be conveyed out.