The development of high-speed railways and the progress of heavy rail technology are mutually promoting. The high-speed railway with a speed of 350 kilometers per hour requires a flatness error of less than 0.3mm/10m for heavy rails, promoting the development of high-precision rolling technology by enterprises. The online laser straightening system adopted in China can control the straightness of the entire length of the heavy rail within 0.1mm. At the same time, the demand for long service life of heavy rails in high-speed railways has given rise to the technology of "seamless steel rails". Through a 500 meter long welding and polishing process, the running noise of trains is reduced by 15dB, and the wheel rail wear is reduced by 20%.
Breakthroughs in heavy rail technology also contribute to the development of high-speed rail. The application of bainitic steel heavy rails has extended the service life of high-speed rail rails from 30 years to 50 years. The new coating technology forms a nano level protective film on the surface of heavy rails, effectively resisting rainwater and salt spray erosion, and reducing maintenance costs by 40%. The coordinated development of the two has driven China's high-speed rail operation mileage to exceed 40000 kilometers, accounting for over 60% of the world's total.
