The THERMOLAST® A compound from KRAIBURG TPE has enabled Gutsche Engineering to bond ASA and TPE in multi-component injection molding and make assembling of roof rail covers easier. The component innovation from Gutsche Engineering provides a completely assembled cover with integrated seal for areas where the seal previously had to be mounted under the roof rail in a costly process. Simplifying the assembly process with the OEM is only one of the advantages that multicomponent parts provide.
Experts Say
“We were looking for a TPE for the seal that can be molded directly onto the ASA hard component of the cover and will ensure permanent and reliable adhesion to this copolymer,” explains Martin Gutsche, managing director of Gutsche Engineering.
“Another decisive factor was the TPE’s viscosity, which makes it possible to implement the thin sealing lip geometry without imprints on the hard components by using the lowest mold cavity pressures possible. Along with tool technology and the molding concept, the TPE’s processing and product properties also played a significant role in achieving the required component quality,” he added.
“In order to determine the adhesion of the various material combinations depending on different processing parameters, KRAIBURG TPE offer the service of performing specific tests to check peeling resistance in accordance with the specifications of the VDI 2019 standard,” says Matthias Michl, expert for window encapsulations, covers
and frames at KRAIBURG TPE in Waldkraiburg.
Salient Features of THERMOLAST® A Compound
In addition to established adhesion to polar thermoplastics, the chosen THERMOLAST® A compound features high flowability, which allows filling molds for complex component geometries. The main requirements for the roof rail covers also included high weather resistance, as the covers are mounted at the highest point on the vehicles.
The roof rail system is part of the standard equipment for German premium SUVs. It rests on bases with two-component covers that take advantage of the outstanding processing properties of THERMOLAST® A as well as of its temperature and weather resistance characteristics.
The THERMOLAST® A compound used was not only able to meet the high OEM requirements involving two year-cycles of weathering in accordance with PV 3929 and PV 3930 standards in advance, by achieving > level 4 on the gray scale, but it also proved its value on the component during outdoor weathering owing to its weathering resistance and a thin seal lip geometry. The application implemented with THERMOLAST® A has been in mass production as part of a roof rail system for a premium SUV since the first quarter of 2019.
Companies Info
KRAIBURG TPE offers a broad range of thermoplastic elastomers (TPEs) for interior and exterior applications, as well as applications for engine compartments and power trains of motor vehicles.
Gutsche Engineering – specialized in sophisticated vehicle components – also relies on the TPE manufacturer from Waldkraiburg, Germany, in producing its innovative roof rail cover. Gutsche Engineering has benefited from the cost-effective processing and above all from the outstanding weather resistance combined with cohesive ASA adhesion in KRAIBURG TPE’s THERMOLAST® A compound for this application.
Source: KRAIBURG TPE