CCCC Tianhe Mechanical Equipment Manufacturing Co Ltd, a subsidiary of China Communications Construction Co, announced that it had excavated 1,642 meters of tunnels via using its self-developed tunnel-boring machine, or TBM, underneath the river channel in an eastern Chinese city by the end of last week.

TBM 15 meter diameter.

http://global.chinadaily.com.cn/a/202011/20/WS5fb75d95a31024ad0ba95734.html