An iPul pultrusion system from Pultrex has now been put into operation at Carbon TT in Buxtehude near Hamburg. Image: KraussMaffei |
"We're making vehicles lighter. This will allow them to transport higher cargo loads while using less energy." This is the corporate philosophy of Carbon Truck &Trailer GmbH. A new iPul pultrusion system for lightweight construction profiles made of carbon fiber reinforced plastic (CFRP) is one of the major reasons behind the success of this company based in Stade, Germany. The newly installed pultrusion system, delivered by Pultrex (a British KraussMaffei subsidiary), produces profile parts for around 70,000 vehicle chassis annually.
New location for increasing needs
Carbon Truck &Trailer GmbH (Carbon TT) is based in the "CFK (CFRP) Valley" in Stade / Lower Saxony. The young company specializes in building carbon-fiber-based chassis for lightweight commercial vehicles. Now the CFRP specialists have a new highly automated iPul pultrusion system up and running at their location in Buxtehude near Hamburg. The system was supplied by Pultrex, a KraussMaffei subsidiary. It produces large CFRP profiles in series, which are used in high-load components for vehicles such as buses, small trucks and mobile homes. "The new iPul system makes it possible for us to manufacture components in series at a consistently high level of quality. At the same time, the system gives us another selling point in multi-axial pultrusion – there are only five other systems like this one in the world," says Gerret Kalkoffen, Managing Director of Carbon TT.
The chassis made from CFRP components are up to 60% more lightweight than comparable steel designs that are produced at Carbon TT in Buxtehude. Image: CarbonTT |
Lower weight and higher payload
"Our carbon lightweight construction solutions help in meeting increasingly rigid requirements for sustainability, efficiency and safety. Especially for vehicles powered by batteries and hydrogen fuel cells, carbon fibers provide more material advantages than just their weight," explains Kalkoffen. A CFRP chassis is approximately 60% lighter than comparable steel chassis – this weight reduction lowers CO2 output and increases both the payload and the cruising range. In addition, the CFRP chassis compensates for the additional weight of batteries in electric vehicles and effectively protects them in the event of a crash.
Production at high speeds – just in time
Successful start-up: After the initial commissioning, it took only a few minutes before CFRP substrates could be removed from the new iPul system. The roving reforming, mold, gripper and system technology reliably produced high-quality components. (Photo: Carbon TT)
Customers of Carbon TT set the pace for production with their order quantities and process requirements. This is where the iPul technology can unleash its full performance potential. Production can run at a speed of up to 2.25 m per minute at 20 tons of pulling force. For large and complex profiles, pultrusion can even be carried out at up to 40 tons in parallel operation.
Customized system
When you choose Pultrex, the entire pultrusion system comes from a single source. Image: KraussMaffei |
For wrinkle-free reforming of multi-axial roving, CarbonTT developed its own roving guide, which is being used for the first time on the new system. The injection box makes it possible to quickly and flawlessly impregnate the exceptionally large profiles with thick walls and a high fiber volume fraction.
The fibers are soaked in the injection box with a polyurethane matrix and then shaped into the approximate final profile form. At the same time, the closed box prevents any unwelcome odors which arise during production with open baths.
The mold was adapted and designed by Carbon TT with spring-in and shrinkage taken into account for the final geometry. The profiles are trimmed down to the final dimensions automatically by the system and then processed further.
CarbonTT develops and produces heavy-duty structural components made of carbon fiber reinforced plastic for the automotive industry as well as the corresponding production and assembly methods for manufacturing them cost-effectively. In collaboration with Volkswagen, StreetScooter and Daimler, various chassis designs have successfully made it to the street. Since 2019, the company has had a partnership with Rheinmetall Group with the goal of fast and safe industrialization of developed components and processes. Here, CarbonTT holds utility models and patents in component design, joining processes and automated production.