| 摘要 |
PROBLEM TO BE SOLVED: To provide a boring machine having large boring capability with a small diameter. SOLUTION: This boring machine is so constructed that a roller cutter 19 and a turning tool cutter on a cutter head part 3 which is provided on the forward end part in the advance direction of a shield main body 1 and can be rotated to the shield main body 1, and the cutter head part 3 is provided with a jet nozzle 21 for jetting a water jet to a material to be bored. The material to be bored is primary-crushed by the water jet, the material to be bored is secondary-crushed by the thrust and rotation of the cutter head part 3, and the crushed material to be bored is discharged by a screw conveyer 8. |
