ROLLER-CUTTER DRILLING BIT Russian patent published in 2002 - IPC

FIELD: mining industry; applicable in drilling blast holes in open casts and mines and processing boreholes. SUBSTANCE: roller-cutter drilling bit includes body, changeable section (legs) with shanks and connected roller cutters; bearings blowing channels. Changeable inserted section including their cone pin exterior parts are located inside body of cast single-part structure having long cylindrical surface of lower carrying part drilling in which, in apertures between rollers-cutters, are cylindrical channels oriented upward at acute angle to generating line and to side surface of body. Body internal part has end hollow in form of truncated cone, whose diameter of lower base and whose axis coincide, respectively, with diameter and rotation axis of drilling bit. Section shanks are in form of rectangular parallelepiped and inserted into mating rectangular holes in body end face and are secured to body with horizontal one or several rods secured to body by threaded connections from one side, and by fastening nut from the other side. Fastening nut has hollows of nonround section from outer side for socket wrench, and from internal side, for rod nonround end. EFFECT: higher efficiency of drilling bit operation and reduced expenditures for its manufacture and for drilling operations. 3 dwg