Tunneling Machines
Tunnel Excavators: This is an excavator mounted on tyres. The excavating arm is specially designed. It has a long reach and can turn 360 degrees in very small micro-tunnels also. All its wheels are hydraulically driven hence it can take gradients. Being on tyres, it travels faster than track-mounted excavators. It can pick-up muck from the front, turn 180 degs and unload it onto trolleys or dumpers etc.