Process for sinking bore holes and a boring tool, in particular for exploration and extraction bore holes.

摘要

The method sinks boreholes (6) using a driven rotary tool (50) carrying cutters (5) which are centralised by the pilot tip (10) ahead of them. In the new design, when the pilot tip strikes rocky formations (5), it is displaced. It retracts into the drilling tool against a force, being displaced ultimately to the same height as the cutters. Also claimed is a drilling tool as described.