Tunnel Boring Systems

Tunnel Boring Machines (TBMs) are used to install 48-96-in. OD jacking pipe and are interiorly controlled by an operator. TBMs excavate soil at the face of the bore when hydraulic motors rotate the inner drum, the cutter head excavates and soil is transported via conveyor and haul unit for disposal from the launch shaft. The pipe laser in the launch shaft projects a laser point on the cutter face for the operator to monitor and make steering corrections as necessary. For extended length drives, the AZ100 Total Guidance System is used for tunnel navigation. The all-in-one Tunnel Boring System easily adapts to any jacking pipe with an appropriately sized TBM, yoke and skid sections. A complete Tunnel Boring System is comprised of a TBM, pump unit, yoke, skid, haul unit, conveyor, pipe laser and often a bentonite pump.

Technical Data

Gıided Boring Systems Overview

  • Most suitable for ground conditions allowing for personnel entry including sand, medium to stiff clay, dry or dewatered geology, weathered rock in non-pressurized ground water conditions
  • Drive lengths up to 1,000-lf.+
  • Common types of pipe: RCP, CCFRPM, FRP, PCP, steel casing pipe jacking applications and liner plate, ring beam and lagging tunnel building applications
  • Passive laser guidance system
  • Conveyor and haul unit system soil management


Tunnel Boring Machines (TBMs) range in size from 48-96-in. and consist of nine TBM models with common ease of operating controls. The TBM has a sealed steering joint that allows for bidirectional, full articulation at the face of the bore and a high capacity main bearing. Two-speed drive motors operate in either low-speed/high-torque or high-speed/low-torque modes. This functionality allows operators to precisely tailor cutting speeds and torque in varying geology for optimal productivity. The operator controls steering, maintains line and grade and monitors the soil removal process from an interior control station. As soil is excavated, dirt paddles propel it onto the belt or into the screw conveyor for transport to the haul unit. The carbide single bar, quad bar cutter head comes standard with a TBM purchase and can be changed underground as necessary. Mixed-ground disc cutter heads for high compressive strength geology, closed face cutter heads for unstable ground, sand shelves for loose unstable soil or custom cutter heads are also available.