This European Standard specifies the characteristics of railway wheels for use on European networks.
Four steel grades, ER6, ER7, ER8 and ER9 are defined in this standard.
Some characteristics are defined according to a category 1 or a category 2. Category 1 is generally chosen when the train speed is higher than 200 km/h.
These categories can sometimes be subdivided, depending upon the characteristics.
This standard is applicable to solid forged and rolled wheels which are made from vacuum degassed steel and have a chilled rim. They are to have already been used in commercial conditions on a European network in a significant quantity, or to have satisfied a technical approval procedure according to EN 13979-1 for their
design.
NOTE 1 The definition of other wheels may be found in other documents, such as UIC leaflets or ISO standards.
NOTE 2 The technical approval procedure is not within the scope of this standard.
NOTE 3 "Rim-chilled" describes heat treatment of the rim, the aim of which is to harden the rim and to create compressive residual stresses in the rim.