During operation and during the coupling and decoupling process, forces are introduced into the coupling. These forces cause different levels of stress in the components of the coupling and their interfaces.
The loads at the interface between the coupler head and the pulling and pushing device were analyzed for different impact speeds over time.
The explicit code LS-DYNA was used for the simulation. Because only certain parts of the construction are of interest for the evaluation, the other parts were simplified and idealized to reduce the model size and the computation time to a manageable level.
The analysis identified when the decisive impact occurred during the coupling process and where the highest loads were located, thus highlighting the areas most affected by the design.
Schwab Verkehrstechnik develops and produces automatic couplings for rail vehicles from trams to mainline railways. The rail vehicles are coupled at low speeds. During operation and during the coupling and uncoupling process, forces are introduced into the coupling. These forces cause varying degrees of stress in the components of the coupler and their interfaces. The present task is limited to the coupling process. The loads at the interface between the coupler head and the push/pull device are to be analyzed for different impact speeds over time in order to be able to adapt the design if necessary.
The simulation shows that no unacceptably high stresses occur in the investigated areas. In addition, the analysis shows when the decisive impact occurs during the coupling process and where the high loads occur. These are the criteria for which the coupling must be designed.
For the simulation the explicit code Ansys LS-DYNA is used. Because only certain parts of the construction are of interest for the evaluation, some parts can be idealized in order to reduce the model size and the computing time to a manageable level. For this purpose, the construction is divided into rigid and flexible bodies and masses, springs and dampers are modeled as simpler entities. Friction in the contact between the two coupling heads is also considered. The coupling process is simulated as a transient with initial speeds of 5 and 10 km/h lasting about 0.1 s and consisting of an impact on the sliding plate, a sliding phase, the stop at the jaw and the springback due to the centering. The maximum calculated forces are compared and verified with measurements.