The Pilot Tube Method (PTM) is one of the most popular techniques available to an underground contractor. Pilot tubes are installed with a high degree of accuracy often required in the gravity flow sewer industry while integrating features of other trenchless technologies such as microtunneling, auger boring, pipe ramming, and horizontal directional drilling to install a variety final product pipe.
- PTM Definition: The pilot tube method is defined as a multistage method of accurately installing a pipe to line and grade by use of a guided pilot tube followed by upsizing to install the pipe. (ASCE M.O.P. – No. 133)
- Accuracy: Acceptable accuracy is +/- 1-inch from the design grade and +/- 3-inches from the design alignment at any location.
- Drive Length: Typical drive lengths are 400ft of less. Longer drives lengths have been achieved.
- Ground Conditions: All pilot tube systems are suitable for displaceable soils. Installing pilot tubes in non-displaceable soils, variable ground, and rock may be possible with additional tooling and accuracy allowance.
The installation of the pilot tube is simply the beginning to the versatility of guided boring technology. Explore many of the common sub-methods performed by top contractors around the world.