Crane service provider Sarens has used a Terex CC 8800-1 crawler crane with a boom booster kit to erect an ENERCON E-126 wind turbine at wind farm in the Netherlands: WindparkNoordoostpolder

The Terex boom booster kit is a lattice boom structure with a width of 10 metres and a length of up to 72 metres that is designed to increase the lifting capacity of Terex CC 8800-1 crawler cranes. Terex Cranes developed the kit specifically for application scenarios with large loads and long boom systems, which is characteristic of the requirements involved in erecting large wind turbines.

“It’s as if the kit had been designed specifically for our project at WindparkNoordoostpolder. Needless to say, that’s why we decided to try it out there,” says Sarens Project Manager Hendrik Sanders. Sarens’ client, ENERCON, had asked for a Terex CC 9800 lattice boom crane, but the latter was not available at the time due to Sarens’ large workload. Because of this, Sarens instead offered the customer a CC 8800-1 crane in combination with a boom booster kit, which when configured as required for the lifts at the wind farm, would make it possible to reach the lifting capacities of the next higher crane class without a problem. The increased reach means that the boom booster kit is further enhancing the versatility of Sarens’ fleet, which has a total of six CC 8800-1 crawler cranes.

New machine
Terex Cranes delivered the boom booster kit to the work site in the Netherlands straight out of the factory in Zweibrücken. As requested, the kit was not fully disassembled in advance, but instead was delivered with the frame pre-assembled in order to allow Sarens to save time during assembly at the site.

Boom booster self-assembly
The team scheduled a total of three weeks for setting up the crane, including the boom booster kit adapters and sections – a week longer than usual, since it would be the first time they would be dealing with the new equipment. This is also why the nine members of the Sarens team were provided with continuous support by a team of Terex Service technicians, who literally worked hand in hand with their Sarens counterparts.

With a main boom length of 138 metres – 72 metres of which were contributed by the boom booster kit – and an 18-metres LF extension, the CC 8800-1 crane reached a total boom system length of 156 metres. This was enough to lift the wind turbine components to a hub height of 135 metres while using an angular offset of 20 degrees.

Once the two assist cranes had erected the ENERCON E-126’s tower, it was up to the Terex crane to lift the last components to a height of 135 metres. The 170-tonne nacelle using a working radius of 40 meters; the 260-tonne generator using a working radius of 36.5 metres; the 375-tonne hub, including its hub adapters, using a working radius of 33 metres; and the three fiberglass rotor blades, each weighing 40 tonnes, using a working radius of 23.5 metres. This whole process will be repeated for another 37 wind turbines, meaning that the CC 8800-1 crane will be staying at the site for about one year working together with the CC 9800 crane form ENERCON. Sarens will be using boom booster kits worldwide. In fact, a new kit has already been delivered to Saudi Arabia using eleven 40-ft containers.