Compact multi-purpose thrust boring machines designed for house connections and steel pipe jacking of up to 560 mm O.D. Machines are used in combination with reusable or lost steel casings. Machine bed and additional extension frames allow the use of 6m long casings. Soils are mechanically removed towards the working pit by rotating string of augers. Cutting heads can be replaced when soil conditions change.
PBA 38 / 40 / 85 machines can be equipped with a navigation system and pilot rods in order to keep tolerances required for house and main sewer connections of 150 to 400mm I.D. The string of pilot rods allow a directionally correct soil displacement in boring axis.
Directional control and surveying is done by monitor, optic system with CCD camera and diode target plate.
After successful pilot drilling, laying of reusable steel castings (diameter identical to definite sewage pipes) with inside arranged augers is done, being the steel casings properly and in boring axis coupled to the pilot rods by a reaming stage.
The string of pilot rods is pushed by the reusable casing towards the reception pit where they are recovered. The third working phase comprises the laying of sewage pipes (generally clay pipes). Pipes are attached to the PBA, jacked-in, and push re-usable steel casings towards the reception pit for their recovery.