Wind turbine component inspection

A challenging phase within the construction of a wind farm is the transportation, of the wind turbine components. These components must be transported over long distances during which they often suffer from transport damages (bumpy roads, difficulties during loading and unloading, unforeseen obstructions) which result in cracks, scratches or other defects on the components. A thorough visual check of the components is therefore highly recommended and should be done before turbine installation as it allows to rectify any defect while the component is still on the ground, avoiding expensive and time consuming access method (e.g. rope access, lifting platform).

Moreover, arrival of the components on site is often linked to important conditions in the EPC contract (triggering an important payment milestone). Consistency between the contractual technical specifications of each component and the delivery must therefore be carefully checked before signing off.

3E has been involved in multiple component inspections worldwide where a 3E inspector visits the wind turbine construction site at component delivery to inspect the blades, hub, tower sections and nacelle for any transportation damage and consistency with the contract specifications. These inspections focus especially on the inspection of the blades, one of the most critical components of the turbine and the most vulnerable to transportation damages. The interior and exterior are being visually inspected in detail to detect delaminations within the laminates of the turbine blades. By doing so, a small hammer is used to tap on the blade shell as the excited sound gives additional information about the structural health of the wind turbine blade. 3E also verifies if important documentation has been received and cross-checks important parameters such as serial numbers, types and factory outgoing quality test performed. The resistance of the lightning receptors are tested and the results are compared to the quality test performed in the factory. Other aspects are being checked to be in line with the TSA contract such as aviation lights and markings, applied logo’s, and many more. The inspections form a strong tool for the site manager and the investors before signing off on a large and important payment milestone.

Pictures taken in the interior of a blade during one of 3E’s wind turbine component inspections. The light effect is the result of a long shutter time of the camera capturing the light of the laser measurement tools.

Blade tip damage observed on 3E’s site inspection. The blade tip hit a wall during transportation due to a miscalculation of the truck driver. The blade tip was successfully repaired before lifting.