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Jishi, a tunnel boring machine (TBM), was put into use on Sunday in China's underground iron mine construction in Anshan city, Northeast China's Liaoning province, Liaoning Daily reported.

 

Ansteel Group, China's major steelmaker, officially began construction work on the Xi'anshan iron ore mine project in November last year. The project is scheduled to begin operations in 2027. With an iron-ore reserve of 1.3 billion tons, it will become the country's largest underground single ore-body iron ore mine. And it is the first to apply TBM to the underground iron mine construction, leading in the research and application of TBM key technologies and equipment both at home and abroad.

 

TBM, which is currently the most advanced tunnel construction equipment in the world, has the advantages of fast excavation speed, environmental friendliness and high comprehensive efficiency. It can carry out tunnel construction in complex geological conditions where traditional drilling and blasting methods are difficult to apply. It is widely used in railway, hydropower, transportation, subway and other tunnel engineering projects.

 

According to the report, Jishi has a total length of 188 meters, an excavation diameter of 7.03 meters and a total weight of 1,200 tons. After being put into use, its construction efficiency can be improved by more than three times compared to traditional drilling and blasting methods. (Xinhua)