Patent ID: 7195081

Claim:
A method for boring or drilling, including percussion drilling or rotary percussion drilling, holes in soil or rock, comprising the steps of: forming a borehole by a percussive and/or rotary movement carried out by a drill bit mounted on a drill rod assembly; and introducing a jacket tube coupled with the drill bit into the borehole; wherein the jacket tube is received in a socket provided on the end facing away from the drill bit working surface, of an envelope tube coupled with the drill bit, and that the jacket tube is subjected to a percussive and/or compressive stress on its end facing away from the drill bit; wherein, for the coupling of the envelope tube with the drill bit, a sleeve-like intermediate element is provided for the transmission of a tensile stress exerted by the drill rod assembly on the envelope tube; and wherein a stop surface of the sleeve-shaped intermediate elements provided between the drill rod assembly and the envelope tube as well as between the drill rod assembly and the jacket tube end facing away from the drill bit is each comprised of a stop surface enclosing an acute angle with the longitudinal axis of the drill rod assembly and the envelope tube and the jacket tube, which stop surfaces cooperate with respective complementary stop surfaces of the drill rod assembly or an adapter coupled therewith.