| 摘要 |
A drag type drill bit (10) having a plurality of solid block-like holders (30, 32, 34) secured to and projecting from the bit body (12), each holder (30) having a plurality of cutting elements (36) thereon defining spaced cutting edges 54. Each cutting element (36) has a planar cutting face (46) and a cutting edge (54) extending along the cutting face (46) with the cutting face (46) extending in a generally radial direction with respect to the axis of rotation of the bit (10). The holders (30, 32, 34) are arranged in a plurality of rows extending outwardly from adjacent the axis of rotation of the drill bit (10) and the holders (30, 32, 34) in each row are staggered rearwardly with respect to the direction of rotation.
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