HARD-ALLOY ROCK-BREAKING CUTTING BIT OF CONE DRILL BIT Russian patent published in 2001 - IPC

FIELD: mining industry. SUBSTANCE: invention is used for drilling of boreholes with face flushing with mud solution or water or with blowing of face through with air or gas. Hard-alloy rock-breaking cutting bit is composed of cylindrical tail part and working head coming in the form of mating of convex curvilinear surface and cone. Conicity angle lies within interval 25≅ α <27 degrees and is found by formula α = atc tgD/2(H₃-H₂), degrees, where D is diameter of tail part of cutting bit, mm; H₃ is height from base of cutting bit to crossing of generators of conical part of its head, mm; H₂ is height of tail part of cutting bit, mm. Usage of drill bits with hard-alloy rock-breaking cutting bits with optimal geometrical parameters of head of cutting bit considerably improves indices of their work ( resistance, driving and mechanical velocity of drilling. EFFECT: improved indices of employment of cutting bits. 1 cl, 1 dwg