Abstract: The present invention relates to buttons, inserts and bodies for rock drilling, rock cutting, metal cutting and wear part applications. The buttons, inserts and bodies comprise cemented carbide provided with bodies and/or layers of CVD- or PVD-fabricated diamond and then HP/HT treated in the diamond stable area. The bodies of cemented carbide may have a uniform structure or a multi-structure containing eta-phase surrounded by a surface zone of cemented carbide free of eta-phase.

Abstract: The drilling tool (1) intended to widen a drilling well bears a series of helical arms (3) resting at a first end on a first fixed flange (4) so as to be able to turn on themselves by a portion of a turn under the control of a rotating ring (9) driven by an opening mechanism (10) controlled by a variation in the pressure of the drilling fluid, while the other end of the arm (3) slides along a groove (21) provided in a second flange (5).

Abstract: The present invention relates to buttons, inserts and bodies for rock drilling, rock cutting, metal cutting and wear part applications. The buttons, inserts and bodies comprise cemented carbide provided with bodies and/or layers of CVD- or PVD-fabricated diamond and then HP/HT treated in the diamond stable area. The bodies of cemented carbide may have a uniform structure or a multi-structure containing eta-phase surrounded by a surface zone of cemented carbide free of eta-phase.

Abstract: The present invention relates to a rock bit insert of cemented carbide for cutting rock drilling. The insert is provided with one or more bodies or layers of diamond or cBN produced at high pressure and high temperature in the diamond or cBN stable area.The body of cemented carbide has a multi-structure containing eta-phase surrounded by a surface zone of cemented carbide free of eta-phase and having a low content of cobalt in the surface and a higher content of cobalt next to the eta-phase zone.

Abstract: A threaded joint for coupling two drill rod elements includes a first drill rod element having at least one end thereof a male tapered helical threading with a cone opening angle greater than 1.degree. and less than 3.degree.. The threading has a constant pitch determining an angle of inclination of the decreasing helix as greater than 1.degree. and less than 3.degree. at the beginning of the helical threading. A second drill rod element has corresponding female tapered helical threading. Each tapered helical threading has primary and secondary shoulders on opposite ends thereof and a stand-off between the primary shoulders when the male and female tapered helical threading are manually fitted together. The male tapered helical threading has discharge grooves in an unthreaded zone for deflection of lines of force.