Liebherr supplies rope winches for the world's strongest ring crane

Dutch company Mammoet had big plans and ultimately put them to practice, having constructed the world's strongest onshore ring crane, also known as the SK6000. One of its key components – a gear ring rope winch – has been provided by Liebherr and enables the ring crane to lift extremely high loads.

The SK6000 ring crane is not only the strongest onshore crane in the world, but also an electric crane with highest lifting capacity. Like the other cranes in the Mammoet SK series, the SK6000 can run entirely on electricity, helping customers to reduce the carbon footprint of their projects. The key components of the application are the four gear ring rope winches with a rope pull of 600 kN each, which allow the SK6000 to lift a maximum load of 6,000 tonnes.

Close cooperation - comprehensive delivery

In this important project, Mammoet drew on the extensive experience of Liebherr’s drive technology team and the exceptional quality of Liebherr components. The long-standing partnership also played a particular role therein. From the very beginning, both companies focused on a close collaboration designing rope winches: with direct, personal coordination and short information paths in the construction and calculation of the winch design, whilst adapting the technical characteristics of the rope winches to the crane requirements. These do not only include the massive technical lifting properties, but also the compact external dimensions of the winches, for example, which allow them to be stowed in shipping containers for the worldwide transportation of the crane. “Within the scope of the project, Mammoet also made use of Liebherr’s extensive components portfolio: The large winches, for instance, were equipped with Liebherr-own gear rings, gearboxes and electric motors,” explains Markus Groeber, technical sales engineer at Liebherr drive technology.

Technical data that inspire

The technical performance of the crane is more than impressive: The SK6000 has a maximum lifting capacity of 6,000 tonnes and is capable of lifting components weighing up to 3,000 tonnes to a height of 220 metres. It also has a maximum slewing radius of 59 metres and a main boom length of up to 171 metres. With the fixed jib attachment, it can reach a total lifting height of 274 metres, which significantly exceeds the reach of all other cranes on the market.

As a fully electric, shore-based manoeuvring and loading crane, the SK6000 will, for example, place floating wind turbine foundations on ships for its customers from the quayside and erect entire wind turbines. When in action, this mega crane will be able to reduce the number of crane movements and reconfigurations, making heavy industrial projects more efficient.