30th Annual SPE Automotive Awards: 2001 Plastics Odyssey

Plastics Engineering, Dec, 2000 by Alice Blanco

Ford's Controlled Energy Management Bumper Isolator Wins Grand Award and Chassis/Hardware/Powertrain Award

An energy absorption system used in the 2001 Ford Windstar was voted the most innovative overall application of automotive plastics at the 30th annual SPE Automotive Awards, held November 9 at Cobo Center in Detroit. All award winners reflected the evening's theme--2001 Plastics Odyssey--by demonstrating the ever expanding capabilities of plastics as they break into frontiers heretofore unexplored, with new materials, new processes, and new feats of engineering.

The awards, sponsored by the SPE Automotive Division, recognize the most inventive use of plastics in six categories: Chassis/Hardware/Powertrain, Body Interior, Environmental, Materials, Body Exterior, and Process/Enabling Technologies. A Hall of Fame Award is also presented annually for an automotive plastics application that has been in continuous use for 10 or more years.

The controlled energy management (CEM) bumper isolator, supplied by LDM Technologies for installation on the 2001 Ford Windstar, is a design that offers a highly tunable square wave crash pulse, allowing the system to meet U.S. 5 mph, European 15 kph, pedestrian impact, and high speed crash requirements. The system won in the Chassis/Hardware/Powertrain category, and was also voted the Grand Award winner. With its patented geometric shape, it is said to be the first ultra-thin-walled (1 mm) isolator manufactured from stiff, high flex modulus material (150 ksi) utilizing precision injection molding, hot runner tooling technology. Supplied by ExxonMobil Chemical, the high density polyethylene (HDPE) formulation costs $0.45/lb versus $2.15/lb for expanded polypropylene (EPP) foam, and the molding process saves from $7 to $12 versus foam and $35 versus mechanical isolators per vehicle.

Weight savings versus alternative materials are also substantial. The smaller insulator package, a snap-lock design that is molded in two pieces, decreases front-end and rear-end overhangs, reducing bumper fascia size and providing a cost savings for the manufacturer of $2 per vehicle. The isolator can be produced with as much as 50% recyclate. Tooling was supplied by Waltec Engineering, Inc.

Blow Molded Shelf Panel Selected as Best in Body Interior

Top honors in the Body Interior category went to the blow molded shelf panel in DaimlerChrysler's 2000 PT Cruiser. The strength-to-weight ratio at an ergonomically friendly mass allows this first all-plastic, removable package cargo shelf design from Lear Corp. to perform multilevel, consumer-friendly functions such as load floor extension, storage, and concealment for security.

The blow molding process includes molded-in carpet and patent-pending structural blades. The molding technique, through the use of multiple mold slides, enables the material to be tucked into a web prior to blowing, thereafter retracting to a final molding surface. Once pressurized, the material folds in on itself and creates an I-beam-type structure in the part; the B surface remains flat. Valleys, previously necessary in blow molding to create structure, are not needed.

Requiring nine moving slides to form the part, the bimetallic mold construction is unique, and the shelf is run using multiple mold temperatures to generate a flat product. The tooling supplier is Hobson Mold Works, and the polypropylene-based resins, which can be ground and reused as is, are supplied by Spartech PolyCom. The shelf panel is said to be the first blow molded product to carry a heat transfer label.

Throttle Body Adapter Utilizing Repolymerized Nylon 6 Wins in Environmental Category

The first commercial use of injection molded repolymerized (versus mechanically remelted/ recycled) nylon 6 (PA 6) resin in the automotive industry reportedly diverts an estimated 200 million lbs of nylon 6 carpeting and molded parts from landfills each year. The powertrain application is also said to be the first use of post-consumer recycled material in a critical automotive component. The 5.4L throttle-body adapter supplied by Visteon Corp. meets durability requirements for engine-mounted components and is installed in select 2001 Ford Econoline vans, F-Series pickups, and Excursion sport utility vehicles, with a total volume of approximately 130,000 units/yr.

The 1-lb throttle-body adapter is injection molded using 30% glass-filled Infinity repolymerized resin from Honeywell, which is said to provide mechanical, physical, and aesthetic properties identical to virgin resin. Replacing a sand-cast, machined aluminum part, the throttle-body adapter meets all performance requirements at a weight savings of 18 oz. A 20% cost savings versus aluminum results from the elimination of secondary finishing operations. The tooling supplier is Michael Tool.

Materials Award Goes to SPS Mirror Bracket

Dow Automotive's Questra glass-filled syndiotactic polystyrene (SPS) for a mirror bracket, fitted on the Nissan 2000 Altima, Xterra, and Frontier, garnered first place in the Materials category. Produced using advanced knowledge of metallocene catalysts, Questra, an engineering thermoplastic, has enabled weight savings of 30% in this application by serving as a replacement for glass-filled nylon. Also noteworthy is the observation that the chemical structure of Questra is totally nonpolar; therefore, the material will not associate with moisture. Questra polymers can be processed without drying, and components made from the material will not associate with moisture in use, resulting in parts with superior dimensional stability compared with competitive systems.