Technical training
Blade Repair Standard / V4 2023-05-02
2) Calculate the amount of resin required for each repair layer based upon the weight of the glass-fibre and the size of the core material being replaced. Note down the amount for each layer. Applying the repair WARNING Mixing large quantities of matrix materials can cause a runaway exothermic reaction and lead to a fire. Take precautions to avoid an exothermic reaction by only mixing sufficient quantities of matrix material for the repair being performed, and, where large quantities are required, by dividing this into smaller quantities. 3) For the first repair layer, weigh out and thoroughly mix the matrix material components. 4) Apply resin to the existing laminate with a paint brush, and carefully apply the first glass fibre repair layer. Apply enough resin to fully wet out the glass fibre mat. Carefully roll the mat with a bolt roller to ensure complete wet-out of the fibres with matrix and to remove any air bubbles. 5) For the next repair layer, weigh out and thoroughly mix the matrix material components.
6) Apply the next repair layer and wet-out as described in step 4. 7) Continue steps 5 and 6 until all repair layers are applied.
If the repair is small and only has a small number of layers, it is possible to mix all the matrix material and apply all of the repair layers in one go. Consult the OEM specific instructions for the maximum number of layers that can be applied at a time.
Note
Vacuum bagging
1) Clean the area around the repair and apply flash tape to the blade surface so that it surrounds the repair. Ensure that there are no creases or folds in the flash tape. 2) Apply vacuum sealant tape on top of the flash tape. 3) Apply peel ply on top of the last laminate repair layer and roll this to remove any air bubbles. 4) Apply the release film on top of the peel ply. 5) Apply a thermocouple probe on top of the release film, placing it to the side of the repair so that it does not cause an impression in the repair layers. Guide the wires from the thermocouple probe out from the repair, and seal with vacuum sealant tape. Connect the wires to the temperature gauge. 6) Apply the breather fabric on top of the release film. 7) Cut two lengths of vacuum hose – one for the vacuum pump and one for the vacuum gauge. The pieces should be long enough to reach the vacuum pump and gauge. Wrap the repair end of the vacuum hose pieces with breather fabric to ensure that they do not become clogged by vacuum film or resin. 8) Where the vacuum hoses cross the vacuum sealant tape, additional vacuum sealant tape should be applied on top of the hoses to ensure a seal.
Global Wind Organisation©2023 / www.globalwindsafety.org
149 / 157
Made with FlippingBook - professional solution for displaying marketing and sales documents online