“Some Like It Hot” is not just a movie title, but also the underlying theme of the Röchling engineers in developing a rigid blow-molded material for charge-air tubes.

Previously, heat-resistant charge-air tubes were made of polyphenylene sulphide (PPS) as PPS was the only rigid blow-molded material that could withstand temperatures over 230 degrees Celsius. High costs and fractures within the tube structure, however, were not rare. Röchling Automotive is now replacing this PPS component with one made from polyamide in cooperation with the RadiciGroup, a global specialist for engineering plastics. The new material is not only just as heat-resistant, but also has greater rigidity as well as better quality – all at a competitive price. Upon completing the first rigid polyamide charge-air tube based on an already existing serially produced product, some customers quickly expressed their interest.

We Do Have a Softer Side

Challenges also exist with soft blow-molded materials for charge-air tubes. The rising share of downsized engines makes a better decoupling of movements between the engine and chassis necessary. This decoupling can be achieved via mounted rubber bellows or a single flexible material. The developers at Röchling Automotive have taken on the task of optimizing this decoupling via an integrated soft blow-molded solution that will replace the previously mounted rubber elements.

The result is fascinating: a soft blow-molded charge-air tube without rubber and without additional assemblies. It is a simplified process that provides better tensile strength as well as weight and energy savings. And, best of all, the new material is 68 percent more heat resistant than comparable benchmark material costs. “We have created a thermoplastic solution that can also be used on the hot side of the engine. No other solution can do that,” says Fabrizio Chini, Head of Advanced Development Engine & Fluid Systems. He sees great opportunities for the new material on the market.