Diagnosis vehicle – Modification of bogies
Molinari Rail was awarded a contract to support INFOTRANS with FE simulations, running behaviour simulation and technical support for the modification of an SBB EC coach into an infrastructure diagnosis and measurement car. This modification requires the installation of several pieces of measurement and diagnosis equipment within the coach and externally on the roof and bogies. The measurement equipment on the bogies will be spring-mounted.
The challenge in this project is to modify an existing 23 years old design and to validate the modifications according to current standards. The Technical Experts of Molinari have developed an approach using FE simulations as well as running behaviour simulation to assess the modifications and to demonstrate the structural integrity of the new diagnosis and measurement car for the required homologation by the Swiss federal authority.
The proof of integrity for the modified bogie is therefore demonstrated on a comparative basis considering various bonus factors whereby the bogie may not be more highly loaded than before the modifications.
The behaviour of the sprung components cannot reliably be simulated by the loads specified in the current standards. Therefore the loads for the components and their effect on the bogie were realistically determined using vehicle dynamics calculations.
The results were used to create static and dynamic superpositions which represent the loads during the entire service life. The ensuing sets of results are separately evaluated for the welds or base material using the relevant standards such as DIN EN 15085 and DVS 1612.
For the bogie in the original condition and for two modified versions complete analyses have been performed. Based on a direct comparison, both modified bogies could be approved for the new service conditions with only minimal modifications, enabling the client to carry-out the modifications in a very economic way.