Dynamic Characteristics and Fault Mechanism of the Gear Tooth Spalling in Railway Vehicles under Traction Conditions

Gear tooth spalling is one of the inevitable fault modes in long-term service traction transmission system railway vehicles, which can worsen dynamic load rotating mechanical and reduce operating quality. Therefore, it necessary to study its mechanism guide diagnosis scientifically. This paper established a planar vehicle model with an analytical time-varying meshing stiffness (TVMS) spur gear. Then, analyzed characteristics under conditions. The research found that length depth affect amplitude TVMS at defect, while width affects range loss. crest factor best evaluation indicator ideal low-noise environments due sensitivity linearity, but not good strong-noise environments. Similarly, time–frequency analysis tool cannot significantly detect sideband are excited by spalling. After high-pass filtering, root mean square variance exhibit excellent classification speed independence achievement provide adequate theoretical support for feature selection making strategies gear systems.