Reducing Weight For Better Fuel Efficiency
By incorporating GE's Cycoloy* CE1820 extrusion-grade resin into the design of its new Winnebago® View™ and Itasca® Navion™ motor homes, Winnebago Industries, Inc., was able to reduce the weight of multiple components while achieving outstanding aesthetics and performance. Compared with competitive materials, Cycoloy CE resin's high modulus permits the use of thinner gauges that can potentially reduce weight by up to 17 percent when considering equivalent stiffness of the part with similar geometry, helping to raise fuel efficiency.
As oil prices continue to rise, consumers are becoming increasingly concerned about fuel consumption. To improve fuel efficiency, manufacturers are looking for new ways to reduce vehicle weight. Winnebago Industries, Inc., the leading US manufacturer of motor homes, sought a material that could help with weight reduction while enhancing the stylishness and aerodynamic appearance of two new recreational vehicles – the 2006 Winnebago View and the 2006 Itasca Navion. After considering aluminum, fiberglass, and several resins for multiple exterior design parts, the company selected GE's Cycoloy CE1820 polycarbonate /acrylonitryl-butadiene-styrene (PC/ABS) resin for its high performance, excellent aesthetics, and significant weight savings.
GE Plastics and Winnebago Industries, Inc.
When Winnebago Industries began designing two new RVs for the 2006 model year, the Forest City, Iowa manufacturer targeted several exterior components for weight reduction potential. These included exterior compartment doors, lower valence panel (wheel lips and rear fender), back wall trim (upper and lower), and aero fences. The company, which prides itself on leadership in technology and design, felt that an innovative material solution could deliver lower weight while maintaining the high standards of performance and appearance that are hallmarks of Winnebago Industries‘ products.
Specifically, these parts required high flexural modulus for rigidity, high impact resistance to withstand road debris, a low coefficient of thermal expansion (CTE) to maintain space between panels, weatherability in harsh outdoor conditions, flexibility to accommodate complex designs, and superior aesthetics to enhance the new RV models.
Larry Richtsmeier, Plastics Plant Manager, Winnebago Industries, said, "We did a careful evaluation of different options, including aluminum, fiberglass, and ABS resin, but found that each of them had significant drawbacks. GE's Cycoloy resin, however, met all our criteria, including significant weight reduction. Cycoloy resin helps make these new vehicles more stylish and aerodynamic."
In addition to providing the best material for Winnebago Industries' needs, GE supplied value-added design services. GE's design experts improved the attachment system for the RV side panels to prevent warpage caused by squeezing of one part against another. By allowing the panels greater freedom of movement while keeping them securely attached to the vehicle, the updated design prevents buckling.
GE's Cycoloy CE1820 resin's flexural modulus is approximately 40 percent greater than that of standard ABS resin, permitting the use of thinner gauges to potentially reduce weight by up to 17 percent while maintaining equal rigidity. Compared with fiberglass, the GE material is approximately 35 percent lighter and provides much greater impact resistance. Unlike aluminum, which restricts part designs to flat surfaces, Cycoloy CE1820 resin provides exceptional design flexibility to accommodate the many different shapes and sizes of the RV components. Finally, unlike typical filled material systems that may deliver a substandard appearance due to filler read-through after thermoforming, Cycoloy resin provides excellent aesthetics. The material also provides superior impact strength, heat resistance, and low CTE.
Cycoloy resins are high-impact amorphous PC and ABS terpolymer blends. By varying the ratio of PC and ABS, Cycoloy resin can be tailored to meet specific property requirements to achieve the optimal balance of performance, cost, and processability for automotive body and instrument panels, computer housings, and cellular phones. This alloy features low-temperature ductility, excellent impact resistance, heat resistance, and outstanding aesthetics.
SOURCE: GE Advanced Materials