This document describes requirements for the inspection of freight, passenger, and infrastructure maintenance rolling stock wheels and determination of the action required. This document provides definitions and illustrations of wheel faults and defects. Each defect category has a severity and corresponding action.
The main purposes of the requirements are to:
• reduce the risk of derailment arising from wheel failure;
• reduce the risk of damage to infrastructure caused by wheel defects;
• minimise hunting/maintaining good vehicle stability; and
• minimise wheel/rail contact stresses in order to prevent rolling contact fatigue in wheels and rails.