Nylon Replaces Metal in Auto Transmission Oil Pan

WEB EXCLUSIVE: A 60% glass-reinforced nylon 6 from Lanxess LLC, Pittsburgh, has replaced steel sheet in the extremely flat, yet very stiff S tronic transmission oil pan on the new Audi R8. Extremely high stiffness of Durethan DP BKV 60 H2 EF is said to ensure that the flanges are tight despite the very flat design of the oil pan. Also, the material is well suited for welding to the nylon 66 oil filter cover, according to Frank Krause, a Lanxess specialist for oil-bearing nylon engine-compartment components.

The injection molded oil pan is less than 20 mm tall, allowing the entire engine to be mounted lower. This lowers the vehicle’s center of gravity, which contributes to the Audi R8’s outstanding grip and road handling. The flat design of the oil pan also results is a low flange height. According to Krause, if a standard nylon 6 with 30% glass were used for the oil pan, the flanges would creep and deform on exposure to sealing force, and thus leak. However, the highly-filled nylon hardly creeps at all, and is twice as stiff as the standard nylons, even at 150 C. It also exhibits barely any tendency to warp, which also has a positive effect on the flange tightness.

Along with the oil displacer and a socket for the drain plug, the oil filter is injection molded directly into the pan using a patented technology from IBS-Filtran, the manufacturer of the oil pan. Krause says that if the component were made of metal the oil filter would have to be fabricated separately from multiple components, and would also be significantly taller, thus, non-compliant with the installation space specifications.

Made of 30% glass-reinforced Durethan AKV 30 H2.0 nylon 66, the oil filter cover is welded to the oil filter housing. Krause says, “This example underscores that, contrary to a common preconception, nylons 6 and 66 can be welded together effectively.”