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As the main component of rail transit, the rails are in direct contact with the wheels of the train, and the quality of the rails directly affects the safety and stability of the train. Affected by the dynamics of the train, the pressure, the natural environment and the quality of the rail itself, the rails often suffer from damage such as cracks, wear, deformation and distortion. Therefore, rail damage must be eliminated or repaired in time to avoid affecting the safety of rail transit operations.