Fit-for-service evaluation of cast manganese railway crossings using combined acoustic emission and finite element analysis techniques
N Cheputeh1, P Vallely1, 2, S Kaenwunruen3 and M Papaelias1
1School of Metallurgy and Materials, The University of Birmingham, Birmingham, UK
Email: nxc710@student.bham.ac.uk
2Network Rail, Baskerville House, Birmingham, UK
3School of Engineering, The University of Birmingham, Birmingham, UK
Cast manganese crossings are considered ‘golden’ assets within the rail network environment. Modern crossings are produced using explosion casting methods in order to optimise structural performance prior to installation on the network. Previously, the final work hardening of cast manganese steel used to manufacture the crossings was achieved in service during loading from train wheels. Although cast manganese crossings are designed to remain in service for a minimum of 20 years, several early failures have recently been reported. The fact that the microstructure of cast manganese steel consists of predominantly large-sized austenite grains, which are non-magnetic, profoundly limits the capability of traditional inspection techniques, including ultrasonic testing in detecting potential flaws present away from the surface. As a result, in-service evaluation is currently limited to visual inspection, which is only capable of identifying defects that have broken to the surface and are in the late stages of propagation. An alternative approach for quantitatively evaluating the structural integrity of cast manganese crossings combining the capabilities of acoustic emission testing with finite element analysis is discussed.
Keywords: railway, cast manganese crossing, remote condition monitoring, acoustic emission, finite element analysis.
Keywords: railway, cast manganese crossing, remote condition monitoring, acoustic emission, finite element analysis.
