Support for the development of diesel particulate filters at Robert Bosch GmbH using welding technology

The continuous reduction in the pollutant emissions of diesel vehicles is making it necessary (amongst other measures) to develop diesel particulate filters (DPFs). By incorporating the SLV Duisburg and SLV München branches into the development process using welding technology at an early stage, Robert Bosch GmbH was able to use the external know-how of GSI and to integrate it into the overall development in an optimum way in a time parallel with its own refinement.

For the welded joints of the DPF, it was necessary to carry out a process development for arc welding. For this purpose, the welding process itself had to be optimised and automated and the detailed designing adapted to the boundary conditions of the welding process. In addition to the selection from variants of the conventional joining processes, emphasis was also placed, above all, on the process validation and the permanent know-how transfer to the technical centre of Robert Bosch GmbH. The investigations were conducted not only on robot installations in Duisburg and Munich but also on the installation in the technical centre of Robert Bosch GmbH. The qualification of the welded joints was supported by metallographic (e.g. scanning electron microscopy) and non-destructive testing (e.g. radiography and thermography) methods.

In a first partial step in December, it was possible to successfully conclude the development project which extended over almost the whole of the 2004 business year and was to be continued in 2005.