DIAMOND CROWN BIT Russian patent published in 2006 - IPC E21B10/46 

FIELD: well drilling equipment, particularly rock cutting tools.

SUBSTANCE: crown bit comprises metal body and diamond-containing matrix. Wave resistance of infiltration material in contact with single-point diamonds is 0.8-1.2 of that of single-point diamond. Ratio of linear hard-alloy charge particle dimension to that of wear-resistant hard-alloy filler is from 1:30 to 1:100. Total area ratio thereof is 60:1 - 75:1. Diamond-containing crown bit matrix height is determined from where H is diamond-containing crown bit matrix height, n is number of vibration fronts in diamond-containing matrix, n≥1, W is resonance frequency for zero mode of oscillations at contact place between matrix and well face, E is modulus of matrix material elongation; ρ is matrix material density. Linear dimension of wear-resistant hard-alloy filler particle is 0.2-0.3 of that of single-point diamond built in impregnated matrix layer.

EFFECT: increased operational reliability due to decreased elastic wave reflectivity factor at diamond-matrix boundary, reduced crown bit end vibration and reduced porosity at contact between single-point diamond with matrix material.

3 cl, 2 dwg