Annotation: Due to the fact that during the movement of the train there is a dynamic load variation on the autogaser devices that combine cars, an analysis of the process of this dynamic load was made. Since, in addition to the load, there are still some temperature differences, this led to the occurrence of cracks in the auto-couplings. The possible places of the formation of cracks in the fiery clutches, their causes and the results of their occurrence were analyzed.