Rotary
cutter is an indispensable part of the tunnel boring machine which are
used to excavate tunnels by drilling the tunnel face with a circular
cross section through a variety of ground types. For different types of
geology different types of shields are used for boring tunnels. These
shields are armed with the rotary cutter. Rotary cutting head helps in
producing of a smooth tunnel surface and have little detrimental effect
on the surrounding geology. Chamber of the tunnel boring machine
receives an excavating materials such as soil, sand, gravel, clay and
their mixtures.
Mounted on the forward end of a rotary shaft, rotary cutter penetrates
through the chamber for axial rotation and simultaneously rocks in an
axial direction. The cutter has a conical cutter face plate having holes
for passing the excavated material is received into the chamber to be
discharged from the excavator. A tunneling machine body having a rotary
cutterhead can be moved continuously by exerting advancing thrust force
on it. Due to this force cutter heads are used with great ease for
excavating tunnel in different topography which ranges from hard rocks
to softer soils.
