Since June 15, many areas in southern China have entered a period of continuous high temperatures, with rail surface temperatures in some regions exceeding 55°C, posing safety risks of thermal expansion deformation and track gauge deviation. On the Shanghai-Kunming High-Speed Railway Changsha section, inspection teams utilize the night "time window" to conduct specialized track inspections, using railway rail profile gauges to perform full-scale scanning of rail heads and waists, precisely measuring geometric parameter deviations.

Railway maintenance experts explain that steel rails undergo thermal expansion and elongation in high-temperature environments. If expansion space is insufficient, it can cause "rail buckling," while prolonged high temperatures can reduce rail hardness and accelerate wear. "Traditional manual inspection cannot precisely capture minor deformations caused by thermal expansion, while modern detection equipment can control track gauge errors within 0.5 millimeters." The detection instruments used on-site can simultaneously collect temperature and profile data, generating thermal expansion trend analysis reports that provide scientific basis for maintenance personnel to adjust fasteners and reserve expansion joints. Data shows that through specialized inspections during the high-temperature season, the train delay rate on this line decreased by 62% year-on-year, and track fault handling efficiency improved by 75%.