This door trim panel application exemplifies how engineering thermoplastic resins can contribute to not only the aesthetics of a vehicle's interior, but also to the functionality that automotive designers now require from interior components as they design vehicles to satisfy consumer demand for safety and comfort.
Molded-in hooks, which hold the trim panel tightly to the door itself to prevent rattles, were a functional feature that required the higher performance characteristics that resin offered over competing materials. The door panel is also made functional by the fact that it carries a speaker, has molded- in support for the arm rest, and is delivered to the assembly plant with sound barrier material attached.
More and more, Tier One suppliers like Manchester Plastics look to their material suppliers for valuable technical support throughout the product development cycle.
The one-piece thermoplastic Super Plug™ door module, a manufacturer of engineering thermoplastics, has made its on-car debut with the launch of the 1997 General Motors minivans.
These minivans, sold as the Chevrolet Venture, the Pontiac Trans Sport, the Oldsmobile Silhouette, and in Europe, the Opel/Vauxhall Sintra, sport a Super Plug designed specifically for this vehicle platform, but the design can be translated to virtually any other production car or truck. In fact, a forthcoming midsize GM sedan, to be sold as the Chevrolet Malibu and the Oldsmobile Cutlass, will soon launch with its own version of the Super Plug door module.
Though vehicle owners may never actually see this new plastic component because it's positioned inside the door, it will offer very good quality over conventional systems, along with serviceability that has already been ranked "best in class." To consumers that means fewer squeaks and rattles from the door, and maybe even fewer trips to the service department.
A traditional car door typically houses a complex array of parts that perform many functions vehicle owners take for granted, such as wires and tracks for accommodating the windows and stereo speakers, components for the door locking system, and the frame that provides structure to the door itself. The many intertwining parts make the door an area in a car that is time-consuming and costly to assemble and often dissatisfies customers due to squeaks and rattles and a high incidence of warranty claims.
The Super Plug integrates the function of many of these door components into a single thermoplastic part, reducing the number of parts inside the door by up to 75%. With fewer parts inside the door, assembly time is greatly reduced, and servicing the door system is made simpler. However, since the Super Plug's design will differ from one vehicle platform to another, parts integration, assembly improvements and serviceability will also differ from platform to platform, depending on the complexity of a vehicle's door system.
External applications
In automotive exterior applications is used resin, polybutylene terephthalate (PBT), polycarbonate because it's a material solution that offers design and styling flexibility while meeting stringent OEN requirements: color and property retention upon weathering precess abitily and mechanical and heat performance.
The air / fuel injection module
Thanks to new technical plastics, which withstand high temperatures and make optimum use of new processing techniques, more and more of functional engine parts are being produced in composite materials. Solvay was among the first in Europe to set up an industrial production line for thermoplastic parts using the fusible-core or the vibration-welding injection technique. This allows the production of parts with complex shapes and compliance with very severe specifications.
Driven by a fully integrated system approach, Solvay Automotive companies provide their customers with a complete plastic module for the air intake function. Made using sophisticated technologies, this module is fully equipped with air intake manifold, resonator, air filter, air ducts, fuel rail, injectors, etc.
This system has major advantages : better design, better engine output, lower weight and thermal conductivity, fewer components, and less assembly work by the car maker. All of this amounts to lower costs and less material waste.
The reasonator on the 1996 Dodge Neon is blow molded from NORYL GTX® resin manufactured by GE Plastics. NORYL GTX® resin gives the application high heat and chemical resistance, and the blow molded design helps reduce engine noise.
NORYL GTX resin is part of a family of engineering thermoplastics manufactured by GE Plastics that cover the spectrum of performance requirements in the demanding environment of powertrain applications. Along with a polyester polybutylene terephthalate resin and a polyetherimide resin, NORYL GTX resin fills a niche role in the powertrain segment.
One recent example of NORYL GTX resin's performance is the resonator on the 1996 Dodge Neon. Both the 2.0 liter double overhead cam and single overhead cam engine options for Neon utilize a blow molded resonator. The decision to specify this resin was based in part on its chemical resistance properties, hydrolytic and dimensional stability characteristics and its ability to withstand temperatures from -40 to 300°F. GE Plastics optimized the blend of polyphenylene oxide and polyamide resins to give a competitive performance advantage over nylon resins. To meet the specification, the part was also required to pass automotive chemical resistance tests for automotive fluids such as oil and antifreeze.
Of primary concern to underhood and powertrain engineers are high heat and chemical breakdown of component materials. Resins are a cost effective material that is engineered to meet these specific challenges. With a heat deflection temperature of 363°F, they can withstand the elevated temperatures that can be generated by a high performance engine. Additionally, very good resistance against chemical breakdown from automotive fluids makes resins a logical choice for applications such as engine resonators.
Another factor in the material specification were resins impressive processing capabilities versus nylon that allow it to be injection molded or blow molded. Steere Enterprises of Tallmadge, Ohio, chose the blow molding process because it was quicker to manufacture and less expensive than injection molding. Tooling cost savings were approximately 15%, and 10 to 20% faster cycle times were achieved versus competitive materials in the application. Blow molding provides the resonator application with important sound-absorbing properties that can help minimize the engine noise that reaches the passenger compartment.
NORYL GTX resin was specified for the resonator application because it combines good mechanical properties with overall system cost savings in automotive powertrain applications, and resins are a versatile material that is engineered to perform in the demanding environment of powertrain applications.
