The rotor blade bearings of this turbine had to be replaced. Changing bearings at a height of 105 metres requires a 125m crane, the assembly and disassembly of which was also going to block the road completely. On behalf of the principal and in consultation with the municipality, the crane company produced a traffic plan to facilitate the operation.
Bearings measuring 2.2m and weighing 1,650kg
The changing of a turbine blade bearing takes a day and a half, which means that the dismantling and re-assembly of three blade bearings can easily take a full working week. In particular, the vulnerability of a 45m long composite blade such as those involved here demands extreme caution, and of course the lowering and hoisting of the bearings, each measuring 2.2m and weighing 1,650kg, requires great care.
Lowering and hoisting step by step
Three Certion engineers were in attendance in the machine room (nacelle) during this operation. They first dismounted the blade, so that the crane could lower it to the ground. Step 2 involved the disassembly of the rotor-blade bearing in preparation for lowering. After that, the new bearing could be hoisted up for assembly. As soon as the bearing had been fitted, the rotor blade was also hoisted up and mounted. This process was then repeated twice more.
Tight plan, clear communication
The job went off well, both from a technical and organisational perspective. The traffic plan and the deployment of traffic controllers constituted excellent preconditions, and there was no hitch whatsoever in the communication between Certion and the crane company; the principal was also satisfied. The wind turbine is now operating smoothly again and generating a massive amount of sustainable energy.