Sommer uses mobile crane for turbine assembly

Germany-based crane rental company Sommer used a Grove GMK6400 mobile crane fitted with both a MegaWingLift and luffing jib attachment for a 131 metre wind turbine assembly.

The wind farm, near Bremen, Germany, only required one assembly to be replaced so it didn’t make financial sense to erect a large crawler crane on the job site, the company said.

Instead, Sommer used the 400 tonne GMK6400 with enough reach and capacity to get to the job site quickly and perform the lift. While many mobile cranes would not have the 131 m reach to replace the turbine assembly, the crane was fitted with a MegaWingLift (lift enhancing system) and a luffing jib attachment to complete the job.

Andreas Meyer, crane operator at Sommer, said, “Crawler cranes conventionally have been used to erect wind turbines due to the fact that they are some of the only mobile cranes capable of reaching these heights. But using a crawler crane to replace a generator that weighs only 1 tonne would have been far too expensive for this project. After visiting the site, however, we knew immediately that our Grove GMK6400 had the capacity and reach needed to perform this challenging lift.”

The crane used has a 60 m boom. When rigged with the luffing jib that extends from 25 to 79 m and the maximum tip height reaches 134 m. With this setup, the crane can perform lifts no other six axle or even seven axle crane can currently achieve, Manitowoc said.

The crane was fitted with a MegaWingLift system and a luffing jib bringing its reach to 133 m. Its capacity was also enhanced to 8.9 tonnes, which easily handled the 1 tonne wind turbine assembly. In all, the job took two hours to complete.