Procedure for reliable durability validation of train axles

Abstract

Die Betriebsfestigkeit von Radsatzwellen hängt sowohl von der Betriebsbelastung als auch der Schwingfestigkeit ab. Zur Bewertung einer Radsatzwellen-Ausführung müssen die zeitlich veränderlichen Betriebsbeanspruchungen in einzelnen kritischen Bereichen, dargestellt durch die Beanspruchungskollektive, berücksichtigt werden. Die zulässige Beanspruchung in einzelnen Bereichen der Welle hängt sowohl von der örtlichen Ermüdungsfestigkeit als auch dem Beanspruchungskollektiv ab. Die Methodik zur Betriebsfestigkeitsbewertung von Radsatzwellen erstreckt sich sowohl auf die rechnerische als auch experimentelle Vorgehensweise. Ergänzend sind die Einflüsse der konstruktiven Auslegung, der Werkstoffeigenschaften und der Fertigungsverfahren auf die Betriebsfestigkeit behandelt

Design review of a freight railway axle: fatigue damage versus damage tolerance

“…A first approach to optimize design can be to overcome the simple assessment in current standards [1][2], is to carry out an assessment based on fatigue damage calculations based on the fatigue damage calculated according to the , relative Miner rule' [12].…”

Structural durability criteria for commercial vehicle components from the self strengthening cast ausferrite nodular iron EN‐GJS‐800–8 (ADI) in comparison to the ferritic EN‐GJS‐400–15

“…For chassis components, such as for example wheels, wheel-hubs, stub-axles or steering-rods, it must be assured that the required service life will not be reduced by rare special event loadings occurring from 10 up to 1000 times 1 Fraunhofer-Institute for Structural Durability and System Reliability LBF, Darmstadt/Germany 2 MAN Nutzfahrzeuge AG, Munich/Germany within the life cycle, possibly causing local remaining deformation below the structural yield point. Furthermore, it must be assured that, prior to a fracture caused by accident-like events, an energy release by local plastic deformation occurs, changing the failure location within the component but not yet causing total failure; this prevents serious aftermath of accidents [2].…”

“…Consideration of these issues jointly results in a structural durability design of the components. Structural components can be identified as primary or secondary components, depending on how strongly they are related to safety and function of the vehicle [1]. Generally, safety components belong to the primary structural component category; their failure endangers the life of the user and other lives in the immediate surroundings.…”

Recent progress in residual stress measurement techniques

“…As early as 1860, Wohler [3] proposed the validation of structures based on fatigue strength and indicated that residual stress contributed to the fracture of train axles. During operation, the working stress superimposed on internal residual stress reduces the margin of safety within the material.…”