The first Liebherr LR 11000 to be fitted with a Power Boom attachment has gone to work in Germany.
The 1,000 tonne crane used the new P.Boom for the first time to place a large turbine house, weighing almost 220 tonnes onto a tower near Cuxhaven in North Germany.
The 6.2 MW pilot system was erected by Senvion (previously REpower) in the new test field for offshore wind turbines. Crane company Nolte decided to use a Liebherr LR 11000 crawler crane owned by Austrian based Felbermayr, while supplying the assist cranes from its own fleet.
The LR 11000 was shipped to Bremerhaven from the Romanian port of Konstanza after completing its first lift at a refinery near Bucharest. It was then transported to the site and fitted with the new boom.The crane was ready to start lifting seven days after its arrival on site. It was rigged with a hook height of 147 metres. Sections from the crane’s luffing jib are used within the double lattice section of the main power boom. The standard main boom sections are then used to create a heavy luffing jib. This configuration provides a 50 percent increase in critical lift capacities on the jib.
Klaus Ruhland, a Felbermayr project planner speaking of the lift, said: "Normally a 1,350 tonne Liebherr LR 11350 or a Terex CC 8800 would have been required for this lift. The 220 tonne load, had to be lifted to a height of 130 metres at a radius of 30 metres. Just for comparison, without the PowerBoom, it would only have been able to manage around 160 tonnes at this height and radius".
The massive turbine is driven by a three blade rotor with a 152 metre diameter which was fully pre-assembled on the ground before being lifted into place.
The crane was rigged with 78 metres of Power Boom, a 66 metre luffing jib and a 42 metre derrick boom. A total of 590 tonnes of ballast was used, including a 50 tonne central counterweight, 220 tonnes of superstructure counterweight and a 320 tonne suspended counterweight.