Liebherr has developed a special tower crane for the construction of wind turbines with hub heights from 110 m in weak-wind regions. This crane of the 630 EC-H 70 Litronic type is built-up on the foundation of the wind turbine and is configured so that the necessary lifting height can be attained with only one guying on the wind turbine tower. In doing so, the 630 EC-H 70 Litronic crane can lift loads of up to 70 tonnes.
As a rule, wind turbines in weak-wind regions are not part of large wind farms but are erected in woodlands or in inaccessible areas. Using this tower crane offers particular advantages in respect of such locations. On the one hand, transportation vehicles with special permits are not required for the delivery and removal on roads that frequently do not have special surfaces and, on the other hand, the assembly of the crane and the wind turbine on a relatively small surface is possible.
The special wind turbine tower crane was used for the first time in Bischberg in the Upper Palatinate for the construction of a new generation of hybrid towers with a hub height of 140 m. Liebherr developed the innovative crane solution together with Max Bögl Wind AG from Neumarkt. The 630 EC H 70 Litronic “wind turbine” tower crane achieves a lifting height of 151 m with only one guying attached to the wind turbine tower. Up to a lifting height of 93.1 m, it operates freestanding for this type work.
With a required load of 70 tonnes, the entire wind turbine tower, the nacelle and the rotor blades were assembled using the tower crane. The load at the jib head is 10,700 kg at a maximum working radius of 30.9 m.
The tower crane was built-up on a reusable foundation frame. Years later, smaller tower cranes can also be inexpensively built-up on this, to carry out work on the nacelle or on the blades of the wind turbine.