Wind turbine blades made quicker with adhesive tapes

Efficient resin infusion moulding (RIM) relies on vacuum-assisted resin transfer provided through spirals located in the moulds. These are temporarily fixed and removed after processing with tesa 51960 fabric reinforced double sided PP film with a differential (different adhesive coat weight either side of the carrier) acrylic adhesive. The side with the highest adhesive coat weight bonds to the spiral preventing lift-off during moulding while enabling residue-free removal after processing. Similarly, resin infusion profiles which speed up the preparation process before RIM starts are securely positioned and fixed into the resin distribution net using tesa 4970, a double sided PVC tape with acrylic adhesive and tesa 4914, a double sided non-woven tape, again with differential adhesive. During the production of wind turbine blades the acrylic adhesive is essential as a natural rubber based adhesive system would contaminate the blade structure and affect its life cycle performance properties. Essential anti-stick surfaces inside RIM moulds are created with tesa 4810, a single sided PTFE laminated glass cloth tape with a silicon adhesive. Here the tape eliminates the time-consuming process of using liquid mould releasing agents and avoids the potentially damaging transfer of liquid release agent to the surface of the turbine blades and other finished components. Also assisting the RIM infusion process are 'flash tapes' which are used for temporary masking inside or around the mould. The excellent performance of both tesa 61122 and 61123 on the low energy surface of moulds makes them ideal for this task. Different thicknesses of these tapes are used to meet varying tensile strength requirements. Once complete, turbine blade leading edges are permanently protected with tesa 54994 which extends the performance to the gel coat on the part of the blade under most stress. Already approved by some major OEMs and Tier 1s the tape does not stain, lift or dry out. For unpainted storage and during transportation of blades tesa 50530 Bodyguard is specified. Widely used by car manufacturers for the protection of new cars, this tape is UV resistant for up to nine months. For more information, either call 01908 500235 or email jeremy.smith@tesa.com Supporting information: www.tesa.co.uk