HISTORY OF FATIGUE TECHNOLOGY FTI has spent the last 45+ years serving the aerospace industry. What started out as a simple wire forming co...
Hole Reinforcement for Composites
FTI's patented GromEx system is a cost-effective method for reinforcing fastener holes in composite materials using a thin interference fit metal sleeve or grommet. GromEx is based on FTI's proven cold expansion technology and is designed specifically for use in composites.
The amount of radial expansion of the grommet in the hole is carefully tailored to ensure adequate grommet retention and at the same time prevent localized damage to the composite. The GromEx system is easier to install, more reliable, and has improved performance over adhesive bonded or swaged grommets.
FTI expanded products achieve excellent bonding and grounding (or earthing) performance because each product is radially expanded from a clearance fit starting hole to produce a final interference fit in the structure or component. Our highly repeatable process produces uniform contact with the hole surface without gaps or insulating sealant. GromEx panel liners are used to protect composite panels from lightning strike damage and hole wear. They are suitable for use with any class or fit fastener and can be used to facilitate the installation of net fit fastners in load transfer applications. GromEx is available in common fastener configurations including "t-shape" and 100 degree countersunk configurations.
Benefits of GromEx