China Completes World’s First 35,000-Ton Heavy-Haul Train Group Test

On December 8, China Energy Investment Corporation announced a major breakthrough in one of its top ten flagship science and technology projects—the Heavy-Haul Grouped Train Operation Control System—with the successful trial of the world’s first 35,000-ton heavy-haul train group.

The achievement marks a transformative milestone set to reshape railway technology and significantly affect global railway development.

The 35,000-ton train represents the longest heavy-haul train group test in China. During the trial, seven separate train groups at Nalingoumen, Shabazi, Guannianfang, and Dalad North stations in Inner Mongolia, were dynamically assembled into a single “virtual train group” using wireless virtual coupling. The trains operated in a closely synchronized mode and eventually traveled to the south yard of Wanshuiquan South Station, where they automatically decoupled and entered the station separately.

The heavy-haul freight train control system project aims to replace traditional mechanical couplers used between 20,000-ton and 30,000-ton long heavy-haul trains with a “virtual soft coupling”, allowing multiple smaller formations to operate as a single train in an autonomous, closely-following grouped mode. Since its launch in 2022, the project has set a series of world firsts.

The project has completed core scenario verifications for single locomotives, 5,000-ton loaded and unloaded trains, and 10,000-ton empty trains, achieving a departure interval of 3 minutes and 43 seconds for 10,000-ton empty trains and pushing 10,000-ton heavy-haul operations into the 3-minute interval era. At a speed of 60 km/h, grouped operation reached a following distance of 1,091 meters for 5,000-ton loaded trains and 943 meters for 5,000-ton empty trains, demonstrating major advances in precision control.

As a major innovation in China’s railway technology, the heavy-haul freight train control system not only validates the collaborative control capability of railway signaling systems under high-density operating conditions but also fundamentally addresses the long-standing challenge of enhancing heavy-haul transportation efficiency.

Looking ahead, this technology will be extended to high-speed rail, urban rail transit, and conventional railways, providing core technical support for China’s railway sector and driving global heavy-haul train control toward higher efficiency, greater safety, and smarter operation.