CONE ROCK BIT Russian patent published in 2023 - IPC E21B10/16 

FIELD: drilling techniques.

SUBSTANCE: rock cutting tool, namely a cone rock bit for rock drilling. The cone rock bit consists of a hollow body, the body of the bit includes foots with trunnions inclined relative to the axis of rotation of the bit, cones are attached to the trunnions with the possibility of rotation on the trunnions around their own axes by means of bearings. The cutters are mounted on trunnions with their rotation axes displaced relative to the bit rotation axis. Each cutter has milled cutting structure made in the form of rows of milled teeth. Each cutter has a metal multi-cone body made with a main cone extending from the top of the cutter to the calibrating vertex of the peripheral row of cutter teeth, which is in contact with the borehole wall, and a calibrating truncated cone having a larger and smaller base, while the smaller base is made from the back side cone contacting the trunnion, the smaller base has a point of contact with the borehole wall, and the larger base extends from the calibrating vertex of the peripheral row of cutter teeth, which has a second point of contact with the borehole wall. The generatrices of the main cone and the calibrating truncated cone of the body of each cutter have straight lines. A hard-alloy layer is deposited on the outer surface of this calibrating truncated cone of the metal body of each cutter with the possibility of forming a calibrating surface of the carbide layer. The profile of the outer surface of the specified carbide layer is made with a generatrix in the form of a convex curve, each point of which is formed by the intersection of the calibrating surface of the carbide layer with the borehole wall when the cutter rolls along the bottom-hole during the rotation of the rock bit. On the smaller and larger bases of the calibrating truncated cone of the cutter body, the thickness of the carbide layer decreases to zero, forming the corresponding first and second points of contact of the cutter body on the smaller and larger bases with the borehole wall.

EFFECT: increasing the efficiency of the rock breaking of the bottom.

5 cl, 6 dwg