Matthias Mitter, Category Manager Welding, Bossard Group (on the left) and Mark Maibom, Industrial Engineer Expert, Johann Borgers GmbH
Breaking new technological ground
Since 1866, the name Borgers has been synonymous with top quality textile components. Johann Borgers GmbH focuses primarily on custom solutions for automobiles and commercial vehicles: fittings for the engine compartment, the passenger compartment, the trunk, and the exterior. A variety of fastening methods are used to install these elements. For a luxury SUV, Borgers used Bossard's new MM-Welding® technology to attach a special loading floor in the trunk.
What are the fastening challenges in your automotive field?
Mark Maibom: We produce coverings and absorbers for side walls, trunk loading floors, and rear window shelves, among other things. The spectrum of materials used ranges from thermo- and duroplastic carriers to needle felts, polyurethane films, and genuine leather applications. There are a number of fixing points for this materials in and on the vehicle. The focus is on new fastening technologies which offer real economic benefits.
How does the MM-Welding® technology work?
Matthias Mitter: The MM-Welding® method uses ultrasonic vibration to push thermoplastic fasteners through the top layer of porous sandwich materials without the need for preliminary drilling or processing. This literally takes only a second. The friction between the fastener surface and the component even turns the surface of the fastener into the connecting material. Thanks to its material hardness, the fastener still maintains its shape and can be loaded immediately after the connecting process.
Why did you select this new technology?
Mark Maibom: The MM-Welding® technology appeared to be tailor-made for us, since so many of our products are based on the porous PUR sandwich components for which the process was developed. Previously, we used conventional joining techniques, but they always involved extra work and limitations. For example, we always had to pre- and post-process the drill hole or factor in longer hardening and drying times.
How did you approach the development?
Matthias Mitter: Bossard developed this innovative fastening solution together with the Swiss company MultiMaterial-Welding AG (MM-W). Specific material tests were conducted together with the Borgers development team. During the first practical trials, we also calculated the future potential for cost savings.
Can you briefly describe the challenge you encountered in the pilot project?
Mark Maibom: The pilot project involved a lightweight, highly stable truck loading floor with a paper honeycomb core. This requires a number of fasteners, some of which attach to the chassis of the car and center the loading floor above it. The special challenge was to place the fasteners as close as possible to the edge of the loading floor.
How does the fastening solution you are now using look like?
Matthias Mitter: Because of the specific requirements, Bossard and its partner developed special MM-W pins. We have found a cost-effective solution using self-tapping screws. The MM-Welding® technology allows these screws to be set close to the edge, directly from above and invisibly. The fasteners are reliable even under heavy loads.
Has the new fastener technology proven itself?
Mark Maibom: We were entering uncharted territory with the MM-Welding® technology, which is always a risk. That is why we are so pleased that everything went smoothly. The final solution is absolutely convincing, both from a technical and an economic point of view.