Mammoet has introduced two cranes that were designed to conduct wind turbine construction and maintenance projects safer and more efficiently. The WTM 100 and the WTA 250 wind turbine cranes use the turbine’s tower as a point of support, allowing them to lift and lower components to greater heights than the equipment that is currently used. This enables wind turbine manufacturers to further increase the capacity of their turbines with greater height and scale.
Wind turbines are getting bigger and higher, reaching physical limits as they become higher than conventional cranes can reach. Mammoet recognized the limitations on current cranes and set out to develop two new wind turbine cranes: one for wind turbine assembly and one for wind turbine maintenance.
Models of Wind Turbine Construction and Maintenance Crane
The WTA 250, or Wind Turbine Assembly Crane 250, has a capacity of 250 metric tons. It will be developed with engineering firm MECAL, which provides the wind turbine tower design. It is installed on a guide rail that runs along the bottom turbine section and can lift the next section using the turbine’s tower as support. Once the next section is installed and equipped with a guide rail, the crane can push itself up along the rail and repeat the process for all of the subsequent turbine sections. Once construction has been completed, the guide rail can either be removed, or remain in place to facilitate easy access for future maintenance operations.
The WTM 100, or Wind Turbine Maintenance Crane 100, works similarly to the WTA 250. The crane 100-metric-ton capacity, and it is attached to two pre-installed hoisting eyes. It can pull itself and the load up along the turbine using the tower for support. The WTM 100 has been equipped with claws that wrap around the tower to keep itself steady. The use of this crane requires minimal modification. It can be used on turbines that have been equipped with pre-fitted hoisting eyes and, in some cases, it can also be used on existing turbines.
Wind Turbine Construction and Maintenance Crane Benefits
“Both cranes are compact: The WTM can easily fit into two standard-sized containers, and the WTA only needs two transport trailers to be moved on site. This makes them easy to mobilize and relocate, and much more efficient than conventional alternatives.” explained Wessel Helmens, Mammoet’s innovations director. “More importantly, both cranes eliminate the height restrictions for turbines and render both the assembly and replacement process faster and more cost-effective.”
In addition, the cranes offer safety benefits, Helmens said. “Because the cranes are attached to the tower, they have no footprint, making the need for additional ground reinforcements virtually redundant,” he said. “The tower-based design also puts the crane and the operator closer to the work area, rendering assembly and maintenance both safer and easier.”
Mammoet is currently discussing the first applications of this new technology with their customers. They are also exploring other versions. “Depending on the input from our customers, we may introduce more additions to the WT-series,” says Helmens.