Welti-Furrer used a Terex TC 2800-1 lattice boom truck crane for lifting and a Terex AC 120 as an auxiliary crane. The location presented Welti-Furrer with a tight time scale resulting from access roads being blocked by snow most of the year. Narrow roads made transport difficult, Terex said.
Tobias Schöpfer, head of communications at SwissWinds said: “This is where the Terex TC 2800-1’s compact design and comparably small weight came in, as it allowed us to avoid doing any damage to the roads”
SwissWinds employed a “Millipede”, a specially designed multiple axle carrier transportation system, to carry the parts required.
In a previously inspected area, the firm placed 20 sq m stabilizer pads to support each outrigger.
Werner Häfliger, head of the Welti-Furrer branch office in Zürich, said, “This enabled the crane, with its 14x14m support base, to work with enormous lifting capacities despite the difficult location. In fact, these lifting capacities are significantly larger than those provided by comparable crawler cranes (due to the greater support base), which also played a vital role in our decision to use the Terex TC 2800-1 for this project.”
Welti-Furrer used an additional crane in the 300t capacity class to attach the front 50m-boom section while it was suspended in the air, before it reeved the hook block and raised the main boom.
Operators didn’t have enough space to move the crane’s derrick boom and Superlift ballast, and so they configured a 96m SH/LH boom and a 200t counterweight. The Terex TC 2800-1 could function with the required radii.
Managers used the crane to pre-assemble the concrete towers, working with a 12–16m reach. A reach of 70m was required to unload rotor blades from the Millipede system. Erection followed using a 38m working radius.
Peter Häfliger said the TC 2800-1 was right for the job. “The enormous range in terms of reach was yet another important challenge that we had to deal with while carrying out this project, but by using the Terex TC 2800-1, we were able to overcome it without a hitch,”
Finally, Welti-Furrer team lifted the nacelle, along with a 50t generator and 70m rotor to an 85m height.
Terex said the project confused pack herders: “The crane’s presence was particularly baffling to a group of pack animal drivers that passed right alongside the erection site while traversing an old smugglers’ route with their donkeys. In fact, they could not help but ask whether the large crane had actually been flown up there with a helicopter.”
