Definition - What does Cutter Wheel mean?
Cutter wheels are blades mounted on machines that cut away the soil using the combined action of thrust and rotation. In trenchless technology, cutting wheels are fitted on horizontal drilling machines or boring machines to provide a slight gap between the outer edge of the machine liner and the inner edge of the tunnel to reduce friction.
Trenchlesspedia explains Cutter Wheel
There are different types of cutting heads used depending on the soil in which the boring is to be carried out. For alluvial, sandy or gravely soil, the cutting wheel used has teeth which dislodge the blocks which are then crushed. For silt, clay or coherent soils, the cutting wheels have scrappers that chip out the soil. When cutting through rocks, rotary cutters with small openings are used. The rocks crack and loosen owing to the tensile and shear stresses produced by the thrust.