A polyamide rear axle transmission crossbeam ready for production

ContiTech uses its knowledge in lightweight construction to conquer other areas of application where metal once dominated. For the first time, the bearings specialist from Hanover in Germany has developed atransmission crossbeam from fiberglass-reinforced polyamide BASF Ultramid for the rear axle, which is used in the Mercedes-Benz S-Class.

The new variant is about 25 percent lighter compared to die cast aluminum versions. “The new rear axle transmission crossbeam is a milestone in the use of polyamides in the chassis and has the potential to set a new trend in the automotive industry,” says Kai Frühauf, head of the ContiTech Vibration Control business unit. “Polyamide is increasingly replacing metal. And we’re right there in the forefront helping manufacturers gradually replace metal with high-performance plastics.”

The rear axle transmission crossbeam from ContiTech is used in Mercedes-Benz vehicle models with all-wheel drive – with the exception of the AMG range. As a central component of the rear axle, it supports forces and torques of the rear axle transmission.

“Absolute precision is called for in the design and production of the transmission crossbeam for the rear axle – particularly in terms of strength and dimensional accuracy of the component,” emphasizes Diethard Schneider, head of lightweight construction pre-development at ContiTech Vibration Control. “Only when all the properties are exactly right can the component be assembled in the axle system without any problems. The fact that premium suppliers are among the forerunners shows the trust and confidence that engineers have today in the performance of our polyamide components for engines and chassis.”

Thepolyamide:a material with plenty of potential

Polyamide components make an important contribution in terms of reducing weight and making vehicles more environmentally friendly. Unlike aluminum, polyamide can be shaped at lower temperatures, thus requiring significantly less energy in the manufacturing process. There is also a wide range of possibilities in recycling.

Since 2006, ContiTech Vibration Control has been using BASF Ultramid for bearings in automotive construction. Product solutions include heavy-duty engine mounts, with the annual production volume in 2013 exceeding three million. In 2009, the bearings specialist also launched a lightweight transmission crossbeam from the lightweight material to support the forces and torques of the engine transmission unit. The weight is 50 percent less compared to an aluminum component. ContiTech produces the component in an injection molding process. ContiTech has already delivered millions of torque reaction mounts made from polyamide.