Recently, in the construction site of the Yuji Intercity Railway in Zhengzhou, Henan Province, the "Jigoku" and "Zhongyuan No. 1" shield machines with a diameter of 12.81 meters and a length of about 78 meters broke ground, marking the domestically produced first self-developed by Tiejian Heavy Industry. The Taiwan-Taiwan railway double-line super-large-diameter mud-water balance shield machine successfully traversed the 3.8-kilometer tunnel of the key control project of the line.

Zhang Keqiang, service manager of Tiejian Heavy Industry Project, said that this is the first time that the large-section shield machine in China has crossed the South-to-North Water Diversion Main Canal for the first time. The shallowest tunnel is only 9.5 meters deep, which is much smaller than the general tunnel design. Requirements. At the same time, there is a large range of calcareous cemented formations in the tunnel crossing section, which puts high demands on the excavation, scour, slag, sealing system and wear resistance of the shield machine.

In the equipment development stage, Tiejian Heavy Industry, China Railway 16th Bureau and the University Research Institute jointly tackled the problem, using oversized structural components, block design, manufacturing and assembly, high-efficiency mud circulation and cutterhead scouring, and large-diameter boring equipment digital modeling. Multi-source high-power synchronous drive and control, special robot auxiliary operation, high-precision excavation surface gas-liquid independent balance control, ultra-large diameter heavy-duty tube efficient reversal and many other innovative technologies to cope with long-distance and complex engineering geology .

Since its inception in January 2017, the equipment has overcome the difficulties of crossing a complex section in a long distance and successfully crossing the main channel of the South-to-North Water Diversion Project. It has created a single-day excavation of 22 meters, a monthly excavation of 410 meters, and a one-time safe tunneling of 3,800 meters. A new record for large-diameter double-track excavation of domestic intercity railways.