In an eight-week operation, two Liebherr crawler cranes from Emil Egger AG, based in St. Gallen, Switzerland, have erected the country’s second largest wind farm. The six turbines now installed, manufactured by Enercon, are expected to produce 22 million kilowatt hours of electricity annually. An LR 11000 as well as an LR 1700-1.0 have completed the wind turbines, which are almost 140 metres high.
Wind power plays a subordinate role in Switzerland’s national energy mix. Only about a quarter of one percent of the country’s total electricity production, most of which comes from hydropower, is supplied by the country’s 50 wind turbines. Six turbines were erected during the summer months on the Jura mountain range in the canton of Vaud near the border with France. Two modern crawler cranes from Liebherr installed the wind turbines with a total output of 13.8 MWh. With the LR 1700-1.0 as well as the LR 11000, the crane company Emil Egger AG had sent its two most powerful hoisting units to work in the hilly terrain at an altitude of around 1,200 metres.
“The heaviest load cases on this construction site occur during the lifts of the generators. Together with the hook block and slings, I have a gross weight of 71 tonnes hanging from my LR 11000.”
Reported Peter Stricker in the cab of his crawler crane.
The crane operator had equipped his machine with a 114-metre-long main boom in order to be able to handle the greatest assembling heights of around 100 metres. With a gross weight of 65 tonnes, the rotors were somewhat lighter, but visually more spectacular than the generator or nacelle. The 40-metre-long rotor blades were mounted to the hub on the ground to form complete blade stars, lifted and installed. With a special device, these huge components could be swivelled into a vertical position during the lifting process.
In parallel with the 1,000-tonne crawler crane, the LR 1700-1.0 completed the erection of other wind turbines a few kilometres away. On the 99-metre main boom, a 12-metre jib angled at ten degrees provided sufficient lifting height.
“Practice-oriented and user-friendly”
“All the crawler cranes in our fleet are from Liebherr.”
said Managing Director Michael Egger.
In addition to an LR 1250 from the Liebherr factory in Nenzing, Austria, the large load & transport company also operates some of the most powerful cranes in Switzerland with a new LR 1700-1.0 and, most importantly, the LR 11000.
“We rely completely on the Liebherr brand for crawler crane technology because these modern machines are extremely practical and user-friendly. The machines are simply ‘state of the art’. And Liebherr’s service leaves little to be desired – and not just for reasons of physical proximity to the manufacturer. If we have a major problem with our equipment, a mechanic is on site within two hours. And that’s worth a lot.”