Long Distance

Technology for Excavating Long Distances

Bit Replacement Mechanism

  • Trail Method (Main Bit, Special Preceding Bits)

    Bits are replaced by retracting the bit installation saddle connected with a link structure along the guide and into the machine. In addition to bits for cutting shafts, etc., it is possible to change bits according to conditions, such as the soil.

  • Trail Method (Roller Cutters)

    A slide mechanism is used to retract roller cutters successively installed on spokes into the replacement chamber at the center of the machine, so that the bits are safely replaced inside the machine. In the replacement chamber, the inner tube slews in a tubular double-layered structure, which makes it possible to replace the roller cutters of all spokes.

  • Rescue Bit System

    This is a system that, when fixed bits are worn, uses a hydraulic extend-retract mechanism to protrude extendable/retractable bits stored in the cutters to the face. This technology has eliminated the need for replacement work and the bits only need to be replaced once.

High-speed Construction

  • Excavation Shield with Simultaneous Segment Assembly

    This shield is equipped with a mechanism that makes it possible to simultaneously perform segment assembly work during excavation. This can help shorten construction time.

  • Double-Grip Erectors

    Grips are installed on both sides, which shortens the time for holding and removing segments. The aim is to increase the speed of the segment assembly work.