CCCC rolls out China's largest TMB

China's largest tunnel-boring machine or TBM, Great Wall, was rolled out by CCCC Tianhe Mechanical Equipment Manufacturing Co recently. Measured 16.07 meters in diameter, the giant machine is 145 meters long and weighs 4,500 metric tons. 
TBMs are used to excavate tunnels, subway tubes and sewer lines. In comparison with traditional tunnel boring methods like rock drilling, blasting and hand mining in soil, the use of such giant TBMs could minimize the impact on the surrounding ground and produce a smooth tunnel wall, helping certain tunnel projects run through unstable geological conditions. The Great Wall TBM will be used in the reconstruction project of Beijing's East Sixth Ring Road. The project has a 9.2 km-long tunnel section, of which about 7.4 km will be constructed by TBMs.It can achieve an ultra-long tunneling distance of 4,800 meters without changing the tool in Beijing's sand and gravel stratum.