The Mercedes-Benz SL trunk lid, designed with an outer sheet molding compound skin and an interior metal support structure, won one of two first prizes. The design replaces the original two SMC parts and one metal part design. The result is that the trunk lid now extends from the horizontal surface over the vertical license plate area. (Daimler AG photo)
A feature in the July/August issue of European Plastics News looks at the Society of Plastics Engineers’ automotive innovation awards in the U.S. and central Europe.
NEUSS, GERMANY (July 18, 11:55 a.m. ET) — The Society of Plastics Engineers Central Europe has announced its automotive awards, with the Grand Innovation Award going to a powertrain application, the drain channel of the General Motors Co. Opel/Astra, Zafira, Chevrolet Cruze and Buick Verano cars.
And in the United States, SPE in November gave its Grand Award for automotive innovation to an instrument panel for the 2012-13 Ford Escape SUV and Kuga crossover utility vehicles molded by Nanterre, France-based Faurecia SA.
SPE awarded the instrument panel as the largest-ever application to use Trexel Inc.’s MuCell microcellular physical foam process, as well as the first-ever instrument panel made using MuCell foam technology. Due to more a pound of weight savings and a 15 percent faster cycle time, an estimated $3 per vehicle has been saved over compact injection molding.
As previously reported by Plastics News, two materials are used for the panel: Stamax long-glass-fiber-reinforced polypropylene from Sabic Innovative Plastics of Pittsfield, Mass., and 30 percent talc-filled PP from Flint Hills Resources LP in Wichita, Kan.
The panel was also described in a paper on foam molding presented at the VDI Plastics in Automotive Engineering conference in Mannheim, Germany, in March by Carsten Starke, a research engineer in the vehicle technologies and materials department at Ford Research Centre in Aachen, Germany.
Faurecia molds the panel as two parts, a “topper” and a “retainer,” in its Louisville, Ky., facility on three LG injection molding machines with clamping forces of 2,500 metric tons.
He said clamping force is 45 percent lower than compact molding, since low mold pressure reduces mold size. He added that optimization was needed, for example in venting, due to many cutouts and injection points.
At SPE's Automotive Division Awards in June in Burscheid, the Grand Innovation Award-winning drain channel was the star.
The complex, three-dimensional-shaped channel has been molded since November using water injection technology (WIT) by Gebze, Turkey-based molder Teklas Kauçuk A.├ů×. in molds from Turkish mold maker Elvanlar Plastik & Metal, also of Gebzi. The molding is done on one of four of the company’s KraussMaffei machines that are equipped with PME Fluidtec GmbH’s PMEcube WIT processing equipment.
The application uses a Schulman Polyfort grade of unreinforced PP rather than GFR polyamide. It is also noteworthy for using a secondary water-pressure stage to form two flexible bellows.
Two first prizes were awarded in the exterior category. One was for the Mercedes-Benz SL trunk lid, designed with an outer sheet molding compound skin and an interior metal support structure. The 2012 model-year design replaces the original two SMC parts and one metal part design.
The result is that the trunk lid now extends from the horizontal surface over the vertical license plate area. Where there used to be a real interpanel gap in the earlier two-panel SMC design, that can still be seen, but as a design feature looking like a gap. Menzolit GmbH of Bruchsal, Germany, supplies the SMC 420 compound processed by Daimler Group in Sindelfingen, Germany, in tools supplied by HZ FbZ Formenbau Züttlingen GmbH of Züttlingen, Germany.
The other first prize went to Wolfsburg, Germany-based Volkswagen AG for development of a large production-series-capable, high-pressure, resin transfer molded exterior side body panel in Class A surface quality for the carbon-fiber-composite-structured XL1 car. The ultrathin plastic panel was described as “almost as thin” as 0.6- or 0.8-millimeter sheet steel, yet it does not show the orange-peel surface effect typical of painted steel panels.
Second place went to the radiator grille of the VW Phaeton. The part is molded “without any visible trace sign of knit lines” in PC/PET and PC/ABS blends from Bayer MaterialScience AG by chromed plastic specialist Gerhardi Kunststofftechnik GmbH of Lüdenscheid, Germany, in tools from K"ller and Finke. Gerhardi was also among finalists with the radiator grille of the Audi R8 GT, molded in the same blends in tools from K"ller, Kumpenholz, Oelfke and Wedo.
Combined use of thermoplastic and thermoset plastics was awarded in two equal third prizes given to Cie. Plastic Omnium SA of Levallois, France. SMC from Mixt Composites Recyclables and Total Petrochemicals Finnalloy, a 30 percent talc-filled PP, were used, respectively, in inner structural and outer panels in the tailgates of the Peugeot 508 W and the Land Rover Evoque.
The parts are produced and painted by Plastic Omnium, using SMC presses from Pinette Emidecau Industries and injection molding machines from KraussMaffei and Engel. Only the tooling differed, from Sanvito & Somaschini and Tecma Global Solutions for the Peugeot application, and from Shapers Polska and Shapers Arrk Tooling Sermo for the Evoque.
In awarding the tailgate prizes, Rudolf Fernengel, SPE Central Europe awards chairman, commented about part precision: “In sheet steel you can bend a tailgate to fit, which is not possible with plastic, as it either fits or it does not. You also have to allow in the design for differences in the coefficient of thermal expansion.”
Hybrid material use was also involved in the first prize in the interior category given to Johnson Controls Interiors (JCI) for a BMW 3 Touring door panel. This is compression molded in Fibrowood acrylic resin bonded natural fiber with Frimo equipment, and overmolding of components and fixings in 20 percent talc-filled PP is done on KraussMaffei machinery Fernengel said: “All four claddings weigh less than one conventional one and it can’t be made less expensively – except in the Far East.”
Second prize went to a BMW 3 real wood décor trim, molded on SHI Demag molding machinery in an unspecified Bayer MS material by NHBX Trim. The latter also decorates the part with wood veneer from Alpi in Italy, using a Gottfried Joos Maschinenfabrik veneer press.
The third interior category prize went to the BMWi3 Megacity vehicle –this time not for its highly publicised carbon fiber structure, but for a one-step thin film foamed instrument panel. This is molded by BMW in Landshut in Siebenwurst tools using BMW’s PP-SGI structural foam process together with Nordenia’s Groflex film cladding applied by Frimo equipment.
Fernengel said: “The thin film takes up the surface structure just like a diaper.” The part has been produced in pre-series since July 2011 and the BMWi3 is due for launch in September 2013.
In the power train category, R"chling Automotive in Lofers/Laives, Italy took first and second prize. The first prize was for an integrated air intake and charge air cooler system for the VW 1.4 litre engines, which is made in DSM’s Akulon K224 HG6, a 30 percent glass fiber reinforced PA6. The company took second prize for the Audi A4 and A5 net-shape charge air duct made in soft TPV and PA6.
Equal third place went to: Woco Kunststofftechnik for a multi-functional turbocharger housing made in phenolic compound and energy-absorbing and high heat resistance polyamide; and to Polytec for an Audi A5 2.0 TDI cooling water duct produced on SHI Demag machinery in a Schweiger mold in BASF’s Ultramid PA66 GF25 GB5 material. A melt-pushback version of projectile molding is used for the duct.
The only item awarded in the electrical and electronics category was an ambient light rod for the Mercedes SLK R172 model. Molded by Burg Design in a Sch"fer mold on Engel machinery, the rod consists of glass-clear Lexan 8010 polycarbonate from Sabic Innovative Plastics and grey Grilamid TR from EMS-Chemie.