Weber and EJOT developed a unique friction-joining process that can be used to fasten foam and honeycomb core structures as well as carbon-fiber-reinforced plastic and glass-reinforced plastic.
Celebrity auto critic Jeremy Clarkson once called the Audi TT “the Mac Daddy of sport coupes.”
The Audi may, indeed, be all that, but even the Mac Daddy can have assembly issues, and such was the case last year. Some components that were bonded beneath the rear parcel shelf with adhesive were becoming unstuck. That’s not good for any car, but it’s especially bad if the car’s base price exceeds $43,000. Audi engineers needed to solve the problem—fast.
The obvious solution was to replace the adhesive with a mechanical fastener. However, the shelf was made from expanded polypropylene foam (EPP). In addition to shelves, this strong, lightweight, recyclable material has myriad automotive applications, including seating, bumpers, stowage systems, door panels, pillars, floor levelers, head rests, tool kits, crash pads and sun visors. The low-density, closed-cell foam has excellent energy-absorbing and sound-dampening characteristics, but it’s not a great medium for threaded fasteners. They strip out too easily.
Audi called Weber Screwdriving Systems and fastener manufacturer EJOT for help. The automaker was already working with the two companies. It uses Weber’s automatic screwdriving equipment to install EJOT’s flow-drill screws in various Audi vehicles. Could the two companies solve Audi’s parcel shelf issue?
Working together, Weber and EJOT developed a unique friction-joining process that combines elements of automatic screwdriving, plastic fastener anchors, and spin-welding technology for plastic parts assembly. The system can be used to fasten foam and honeycomb core structures as well as carbon-fiber-reinforced plastic and glass-reinforced plastic.Fasteners, News