Railway Vehicle Wheelset: Core Technical Requirements and Safety Analysis

A wheelset is an integral assembly formed by press-fitting two wheels onto a single axle using an interference fit, typically achieved through cold pressing. It is one of the most important components of a bogie and a key factor affecting the operational safety of railway vehicles. Therefore, strict technical requirements and management systems are applied to wheelsets during new manufacturing, major overhaul, depot maintenance, intermediate repair, temporary repair, and in-service operation.

An interference fit is used at the wheel–axle interface to ensure a firm connection. For safety reasons, any looseness is strictly prohibited. The wheelset bears the entire weight of the vehicle, runs at high speed on the track, and is subjected to various static and dynamic loads transmitted from both the car body and the rails, resulting in a very complex stress condition. Therefore, a railway vehicle wheelset must meet the following four basic requirements:

• Sufficient strength to ensure safe operation at the maximum permitted speed and load;

• Minimum possible weight while maintaining adequate strength and service life, with a certain degree of elasticity to reduce wheel–rail interaction forces;

• Low rolling resistance and good wear resistance to reduce traction demand and extend service life;

• Ability to adapt to straight and curved track operation, with the necessary safety margin against derailment.