The tunnel boring machine "Jishi" in Xi'anshan Iron Ore Mine, Anshan, Northeast China's Liaoning province. (PHOTO: ANSTEEL GROUP)

By TANG Zhexiao

A tunnel boring machine (TBM) Jishi was put into use in northeast China's Anshan recently, marking the first time the country applied TBM in the underground mine construction. 

The TBM, also known as "mole", is the equipment used to excavate tunnels through hard rock, wet soil or sand which requires specialized technology. It is widely used in tunnel projects such as railways, hydropower, transportation and subways.

As a type of full section hard rock TBM，Jishi has a diameter of 7.03 meters and a length of 188 meters, with a total weight of 1,200 tons and the advantages of fast excavation and high efficiency.

It can increase mine construction efficiency by more than three times compared with the traditional drilling method. By avoiding surface vibration and noise through non-blasting excavation, it is also environmentally-friendly.