Microtunneling

North American Society for Trenchless Technology defines microtunneling as…
a trenchless construction method for installing pipelines. Microtunneling uses all of the following four features during construction:
  1. Remotely controlled - The microtunneling boring machine (MTBM) is operated from a control panel, normally located on the surface. The system simultaneously installs pipe as spoil is excavated and removed. Personnel entry is not required for routine operation.
  2. Guided - The guidance system usually references a laser beam projected onto a target in the MTBM, capable of installing gravity sewers or other types of pipelines to the required tolerance, for line and grade.
  3. Pipe jacked - The process of constructing a pipeline by consecutively pushing pipes and MTBM through the ground using a jacking system for thrust.
  4. Continuously supported - Continuous pressure is provided to the face of the excavation to balance groundwater and earth pressures.
In simple terms, the microtunneling boring machine will be jacked from the bore pit to the receiving pit at the leading end of a string of jacking pipe. The spoils from the tunnel face will be transported to the ground surface via slurry flowing within a system of pressurized slurry lines. Once at the surface, the spoils will be separated from the slurry by a separation plant. The cleaned slurry is then returned to the face of the tunnel.

Microtunneling
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Since forming in 1992, Nada Pacific has undertaken and completed more than 200 microtunnel bores totaling over 150,000 linear feet on over 75 projects. This is among the highest in the country. These projects have exposed NPC to a very wide variety of conditions ranging from special interest and environmental concerns to very unusual job site locations. In addition to these challenges NPC has encountered practically every geological condition and/or formation imaginable, from zero blow count soils to cobble and boulder laden ground to solid rock. We have completed several drives well over 1,000 feet long that incorporated multiple IJSs and redundant long distance guidance systems.

We take great pride in the fact that we have some of the most experienced and qualified superintendents, MTBM operators and crewmembers in the country.

Please contact us for our qualifications package including a complete list of projects and personnel resumes.