Ford is molding instrument panels in the 2012 Ford Escape and Kuga with the MuCell foaming process in a move that cuts $3 in cost and one pound in weight per vehicle.
|Ford's Chuck Rocco and Junko Pauken show the foamed instrument panel topper during a talk with PlasticsToday.|
In an interview with PlasticsToday, Ford automotive engineer Junko Pauken said that Tier 1 Faurecia has installed three 2500-ton LG injection molding machines at its Louisville, KY plant to mold the parts. Large platen sizes are required to accommodate the tools. Because of lower pressures in the MuCell process, only about 1200 tons of clamping force will be required, she said. The foaming process reduces cycle time about 15%.
"The 2012 Ford Escape/Kuga instrument panel is the first to market utilizing the MuCell process," she said.
The lower weight of the two-piece instrument panel (topper and retainer) yields a slight improvement in fuel economy. According to www.fueleconomy.gov every 100 pounds in weight reduction results in a 2% improvement in miles per gallon.
In the MuCell process, precisely metered amounts of supercritical fluid enter the polymer melt through injectors mounted on the barrel. A specially designed mixing section creates a single-phase solution. Cells start to nucleate when exposed to lower pressure in the mold cavity, resulting in a closed cell structure with a solid skin layer. The pack and hold phase of the injection cycle is replaced by controlled cell growth, which stops when the cavity is filled.
MuCell microcellular foaming technology was invented at the Massachusetts Institute of Technology and in 1995 Trexel (Wilmington, MA) was granted an exclusive worldwide license for further development and commercialization of the technology.
Pauken said that Ford developed a mold flow optimization method for the instrument panel, which she described as the largest-ever automotive MuCell application. She said the tool design was complicated because of the number of holes and features on the parts and the multiple gate locations. Gate design and venting were among the issues optimized. The tool partner is Lamko Tool & Mold (London, ON).
Ford trialed the MuCell process for instrument panels on a 3000-ton machine at the Proper Group in Warren, MI.
The material processed for the IPs is long glass fiber polypropylene. The material suppliers are Sabic Innovative Plastics (Pittsfield, MI) and Flint Hills Resources (Wichita, KS). Sabic acquired the STAMAX long glass fiber polypropylene business from DSM and Owens-Corning.
Ford announced last April its plan to use the MuCell process to produce engine covers for the Focus, C-MAX and Grand C-MAX, S-MAX, Mondeo and Galaxy. Ford has committed to a minimum of 100kg (220.5 pounds) of weight reduction from even its smallest cars, and 300kg (661 pounds) from larger cars, by 2020. In another materials-based effort to reduce curb weight, Ford said it is now making extensive use of high-strength boron alloy steels.
Ford executives told PlasticsToday they are looking for other high-volume applications using MuCell, including those requiring top-quality surface finishes.
The Ford MuCell instrument panel is a finalist in the 2011 Automotive Innovation Awards program conducted by the Society of Plastics Engineers. Winners will be announced at a dinner in Livonia, MI Nov. 9.