On the morning of February 1st, China's largest self-developed domestic TBM "Caiyun" was successfully launched on the "Longitudinal Tunnel of China's First Railway" - the Gaoligongshan Tunnel of the Darui Railway. This is the first time that a domestic hard rock roadheader was formally used in a railway construction tunnel with complex geological conditions in the southwest of Guizhou. It will rewrite the long-term history of the mechanized construction of the railway long-tunnel project in China, indicating that China’s hard rock boring machine technology has reached the world’s leading level. Level.

The Da Li Li Zhi Rui (Li) Railway is located in the western part of Yunnan Province and has a total length of about 330 kilometers. It is part of the Sino-Myanmar international railway corridor of the Trans-Asian Railway (West Line). The Gaoligongshan Tunnel has a total length of approximately 34.538 kilometers. The key railway control project is the longest railway tunnel in China and the longest railway mountain tunnel in Asia. The maximum burial depth of the tunnel is 1155 meters. The tunnel passing area has the characteristics of "three highs" and "four actives". The complex and variable geological conditions are rare in the country and can be called the "Geological Museum" in the history of railway construction.

"Caiyun" TBM is China's largest open-diameter hard rock boring machine jointly developed by China Railway Tunnelling Group and China Railway Equipment Group. Its cutter-disk excavation diameter is 9.03 meters, which fills the domestically developed large diameter of more than 9 meters. Hard rock boring machine blank is a new type of equipment tailored to meet the complex geological environment. The TBM equipment breaks through key technologies such as weak deformation, variable cross-section excavation, rock burst prevention and control, rapid excavation in the crushing layer, high temperature environment response, and prevention and control of water inrush from the tunnel, online real-time geological forecasting system, ventilation refrigeration system, etc. To cope with the risks that may be encountered in the deformation of surrounding rock, fault crushing zone and rock burst, water inrush and mud outburst, and high geothermal heat.

On August 1, 2017, "Caiyun" officially went offline in Kunming. After several months of careful assembly and debugging, "Caiyun" TBM successfully originated on the morning of the 1st, tunnel excavation work was officially changed from drilling and blasting method TBM construction replaces long-distance tunnel excavation that cannot be completed manually. After TBM excavation, the average speed of tunnel excavation can reach 350 meters/month or even higher, which will provide a reliable guarantee for the opening of the Gaoligongshan tunnel and the entire railway in the western Yunnan region.