The kerf is the outside boundary of the tunnel wall that a boring machine gouges out as it bores through the ground or rock.

切口在隧道壁边界的外面，隧道壁是由钻机在钻透土地或岩石时挖出的。

youdao

Specially designed for the manufacture of a drill, boring machine in a position to achieve two of the dedicated machine.

专门设计了制造一个将钻、镗孔在一台机床上实现的两个工位的专用机床。

youdao

A subway construction worker, known as a "sandhog" exits the tunnel boring machine in the northbound tunnel of the Second Avenue subway construction project, Thursday, April 7, 2011 in New York.

2011年4月7日，纽约，被称作“沙狗”的隧道挖掘工人从第二大街地铁建筑工程的北向的隧道的隧道掘进机中走出。

youdao

Bureaucratic systems and processes were put in place to make the system tick over like a boring clockwork machine.

FORBES: Gasp! Machines Still Can't Think!