HEILONGJIANG, Oct. 14 (Liu Baiming) - "Construction orders have been issued, begin track operations. Many tools will be used today, pay attention to personal safety." At 13:30 on October 13, Wang Lei, deputy director of the Bamiantong Track Workshop under China Railway Harbin Group Co., Ltd. Jixi Track Maintenance Section, led his 45 colleagues to begin the day's construction work. Over the next 180 minutes, they needed to complete stress relief construction on 800 meters of seamless track between Liumao Station and the 76-kilometer line section on the Chengjie Railway Line.

Workers conducting seamless track stress relief construction - Photo by Liu Baiming

The Chengjie Railway Line, originally built in 1924, runs northward from Xiachengzi Station on the Binsui Line, passing through Bamiantong and Lishu Town to reach Jixi. Daily operations include 2 pairs of passenger trains and approximately 6 freight trains running on the Chengjie Line. The green-bodied passenger trains 6223/6224 are among the 81 pairs of public welfare slow trains nationwide, serving as convenience trains, market trains, and happiness trains for local residents along the route.

Steel rails have the characteristic of thermal expansion and contraction. Due to the significant temperature differences between winter and summer in northern regions, as temperatures drop, the internal stress in seamless track rails gradually changes from compressive stress to tensile stress. If this tensile stress is not reduced in time before winter, the rails face the risk of "breaking" when winter temperatures become extremely low. Therefore, every pre-winter season, railway professionals like Wang Lei conduct scientific calculations based on factors such as "track curve radius and internal rail stress" to timely carry out seamless track stress relief construction, adjusting internal rail stress to adapt to seasonal changes and proactively eliminate safety risks.

Wang Lei's Bamiantong Track Workshop is responsible for maintaining and repairing 97.6 kilometers of track and 45 sets of switches on the Chengjie Line. Before winter, they will complete stress relief construction on nearly 30 kilometers of seamless track.

Putt-putt-putt... Five workers, each operating an internal combustion bolt wrench, line up at intervals along one rail, loosening rail fasteners from the expansion joint end toward the terminal end. Component team members follow closely behind, organizing rail components and placing rollers between the rail base and sleepers to reduce friction resistance during rail expansion and contraction.

Workers loosening rail fasteners - Photo by Liu Baiming

"One, two, one, two..." After completing the loosening of fasteners on one rail, accompanied by loud chanting, workers from two rail-ramming groups grip thick ropes tightly, pulling rail-ramming vehicles to impact the rails. The multi-ton long rails move bit by bit on the rollers.

"Due to our large stress relief construction scope, using rail-ramming vehicles to impact the rails ensures uniform internal stress throughout the rail, achieving optimal construction results," Wang Lei explained.

Workers conducting rail-ramming operations - Photo by Liu Baiming

After the rail-ramming phase ends and internal rail stress adjustment meets standards, Wang Lei immediately organized his colleagues to remove rollers and tighten long rail fasteners, installing a pre-calculated length short rail at the expansion joint. This completed the stress relief work for one rail.

At 14:40, stress relief work on the other rail began. At 16:10, construction neared completion. Wang Lei and his colleagues conducted final inspections of track gauge and fastener tightness. Some workers began counting and organizing tools and equipment, a critical step after each construction operation, as leaving behind tools could impact train safety.

Personnel conducting quality inspection on-site - Photo by Liu Baiming

At 16:40, as darkness fell, the engineering vehicle carrying construction personnel traveled at varying speeds on the return journey, with wisps of cooking smoke rising from nearby villages.

According to reports, before winter arrives, Jixi Track Maintenance Section will complete 200.3 kilometers of seamless track stress relief tasks, solidifying the track equipment foundation for smooth winter railway transportation.