North America's first multishell, vibration-welded intake manifold debuted on Ford's 5.4-liter, two-valve engines on the 1999 Ford F-series 150 and 250 light trucks, Expeditions and Lincoln Navigators. This manifold also marks the first use of Zytel welding-enhanced PA 6,6 nylon resin.

The component, developed over a 14-month period by a team from Ford Motor Co. (Detroit, MI), Montaplast of North America (Frankfort, KY) and DuPont Automotive (Troy, MI), significantly reduces costs compared with the original lost-core design.

The component was originally designed in thermoplastic for lost-core molding. However, the potential cost savings offered by vibration welding drove the change. With vibration welding, two thermoplastic parts are rubbed together under pressure and at a suitable frequency and amplitude until enough heat is generated to melt and mix the polymer. After vibration stops, the parts are aligned, and the molten polymer solidifies, creating the weld. The process has been used to manufacture air intake manifolds in Europe for the past 5 years and millions of other nylon 6,6 parts worldwide.

To meet the shortened launch time, production tooling was designed directly, eliminating the prototype stage. The availability of Zytel welding-enhanced PA 6,6 nylon resin, in part, allowed the team to take advantage of the benefits of vibration welding. The material was developed in anticipation of a demand for nylon that combined high-temperature performance, enhanced burst strength and weldability. It also offers a 35 percent improvement in static burst pressure at the weld joint and a burst strength of 11 bars, heat-aging properties, chemical resistance and dimensional stability. It's also suited for welded manifolds offering high-performance requirements, such as glycol resistance for cooling crossover applications and high-temperature resistance for exhaust gas recirculation applications.

With just 14 months from design to manufacture, this project illustrates the benefits of teamwork. Ford engineers were responsible for the design relative to performance and function. Montaplast led the manufacturing processes and the layout of the component, and DuPont engineers provided material research, testing and provided significant CAE modeling for the lost-core part that preceded the new application.

For more information on PA 6,6 nylon resin, call DuPont Automotive at 248-583-8000, visit www.dupont.com.