Recently, Hexcel has developed the latest HexPly®XF surface technology, which can significantly reduce the shell processing cycle during the surface treatment of wind turbine blades. HexPly®XF improves the overall blade manufacturing efficiency by reducing the time in the mold (up to two hours) and eliminating surface defects that need to be reworked before painting.
With the rapid growth of the wind energy industry in recent years, wind turbine manufacturers are facing increasing pressure in areas such as reducing costs, improving quality and optimizing productivity. The HexPly XF surface technology aims to solve the limitations of the current surfacing technology of the blade shell surface, that is, pinholes and other surface defects must be repaired manually to achieve the perfect smooth surface required for painting.
The HexPly XF surface technology meets the most challenging surface quality requirements by introducing a new material form as a surface finishing layer. This technology does not require the traditional in-mold gel coating process. HexPly® XF is used to infuse rotor blades. It is a lightweight non-woven semi-prepreg structure containing an epoxy resin matrix, which can be co-cured with standard epoxy resin infusion systems.
The product has a successful record in prepreg wind turbine blades. HexPly XF is easy to handle and is provided in ready-made rolls, and can be quickly coated by manual or semi-automatic meshing equipment. It has a self-adhesive, smooth surface and is protected by a removable protective foil. This side of the prepreg is placed against the mold surface treated with the release agent.
Once the location of the material is determined, the laminate of the blade shell structure can be laid immediately and can be injected into the laminate. After curing, the blade will be demolded with the manufacturer, thanks to the pinhole-free surface, which requires minimal preparation before painting.
The weight of HexPly XF material is less than half the weight of a typical gel coat per square meter, thereby reducing the overall weight of the blade. In addition, the constant area weight and thickness of the prepreg film can provide a completely uniform surface coating to ensure that the blade weight distribution and balance are maintained, which is critical as the rotor diameter continues to increase.
HexPly®XF does not need to process or mix liquid chemicals like the gel coat process, so it also improves the health and safe working conditions of the workshop. This material has a shelf life of 6 weeks at ambient temperature, which also minimizes cold storage requirements and helps reduce waste.