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Where Has the "Clanging" Sound of Trains Gone? | People's Daily

 

 
     Due to limitations in production technology and transportation conditions, traditional railways were laid with 12.5-meter or 25-meter steel rails, connected by joint plates. To prevent the temperature-affected expansion and contraction of steel rails from affecting the smooth operation of the track, a 6mm gap was left between the rails. When a train passed over the gap, the wheels would collide with the rails, producing the "clanging" sound.

　　Now, with advancements in technology, joint plates have been replaced by welding techniques, creating seamless rail connections. Railway maintenance teams replace worn-out rails and switches during scheduled repairs and maintenance periods, gradually upgrading traditional 50kg/m rails to 60kg/m rails. These upgraded rails have significantly improved steel properties such as toughness and density, allowing them to withstand the impact of higher-speed or heavier trains. The newly replaced rails are welded with the original rails to form longer stretches of seamless track. After years of effort, most of the steel rails on the Beijing-Kowloon Railway have been successfully upgraded.

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