BLADED DRILLING BIT Russian patent published in 2024 - IPC E21B10/43 

FIELD: well drilling.

SUBSTANCE: bladed drilling bit includes a housing with blades, each blade is reinforced with cutting elements in the form of inserts, has leading, working and trailing edges. Between the working face and the leading face of each blade there are cylindrical inserts with flat PDC plates. Cutting elements in the form of cylindrical inserts with spherical working surface are installed on the working face of each blade. Cylindrical inserts with spherical working surface have a value of protrusion above the working face of the blade, which is greater than the value of protrusion of cylindrical inserts with flat plates PDC. Cylindrical inserts with spherical working surface have transition from cylindrical surface to spherical, wherein said transition is located above blade working face at height smaller than that of cylindrical inserts with PDC flat plates protruding above blade working face. On the leading side on the spherical working surface of the cylindrical inserts with the spherical working surface there are two flat segment surfaces located on different sides from the cutting path. First flat segment surface extends from the side of the centre of the bit at a lateral angle a₁ to the cutting path, and the second flat segment surface passes from the periphery of the bit at a lateral angle a₂ to the cutting path, wherein the lateral cutting angles a₁ and a₂ have opposite directions and a₁>a_2. Above two flat segment surfaces are located on the spherical working surface at the height not exceeding the value of protrusion of cylindrical inserts with flat plates PDC above the working edge of the blade.

EFFECT: increasing the reliability and service life of the bit.

4 cl, 4 dwg