New Liebherr boom pushes the limits

Liebherr’s new SX boom gives more capacity and increases lifting height for its 750 tonne capacity lattice boom crane models. It moves the LR 1750/2 crawler and LG 1750 truck crane into the 1,000 tonne class for wind turbine erection, Liebherr said.

Turbines with a hub height of 165 metres and component weights up to 120 tonnes can be erected using the new system. This capability was previously the preserve of 1,000 tonne class cranes, the manufacturer said.

Instead of a 3 m wide boom the SX is 3.5 metres wide and the sections have been made lighter. They increase lateral stability to cope with lifting heavier loads. In addition, a boom and fixed jib up to 165 metres long can be raised.

Most noticeable, however, is an extension to the SX boom in the form of a 6 m wide section to further increase lifting capacity. Two 14 m long by 6 m wide sections are the SX2 while with three it is known as the SX3. For transport and storage the 6 m wide sections can be split down their length, according to their open triangulated structure, before being offset longitudinally and then meshed together like gear teeth. In this way the width for transport is reduced to 3.5 m. Bolting together and separating the two halves can be done quickly, the manufacturer said.

The SX is interchangeable between the LG 1750 and LR 1750/2. A new fixed jib designed to make the most of the extra capacity is also available. It includes a runner and anew hook block which, in conjunction with the head sheaves, are designed to prevent the hook block from twist.

The new SX system has been tested and is available.