1 Scope
This document specifies the characteristics of wheels for all heavy rail track gauges.
This document applies to heavy rail vehicles and applies, in principle, to other vehicles
such as urban rail vehicles. Five steel grades, ER6, ER7, ER8, ERS8 and ER9, are defined
in this document.
NOTE 1 Steel grade ERS8 has been introduced in this document as an optimization of steel
grades ER8 and ER9 due to rolling contact fatigue (RCF), taking into account service
feedback from Europe, for example, BS 5892‑3 in force in the United Kingdom.
Some features are provided as a Category 1 or Category 2 function.
The requirements defined in this document apply to cylindrical bores. Most requirements
also apply to wheels with tapered bores. Specific requirements for tapered bores (e.g.
geometrical dimensions, etc.) are defined in the technical specification.
This document applies to monobloc wheels in vacuum degassed steel, forged and rolled,
with surface treated rims, which have already been the subject of extensive commercial
applications on a European network or have complied with a technical approval procedure
according to EN 13979‑1:2023 to validate their design.
Annex A...