Size and shape of the lower part, between the 330 mm and 0 levels on the iron plane and between 0 and – 41 mm below the iron plane, of the rolling stock; guarantees the safety distance from fixed obstacles resting on the roadbed between the rails and in their proximity. It is also referred to as “kinematics” as it represents the limit position that can be reached by the various parts of the vehicle in motion in normal operating conditions and taking into account the wear and the maximum failure of the suspension
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