摘要 |
A drill bit employing a plurality of abrasive, particulate-impregnated cutting structures extending upwardly from the bit face and defining a plurality of fluid passages therebetween. The cutting structures may be configured as spaced posts, or as blades with circumferentially extending grooves at radially spaced intervals. Superabrasive cutting elements in the form of thermally stable diamond are placed between the posts or in the grooves, depending on the cutting structure configuration, and at a reduced exposure. Additional cutting elements may be placed in the cone of the bit surrounding the centerline thereof. The blades may extend generally radially. Additionally, discrete protrusions may extend outwardly from at least some of the plurality of cutting structures. The discrete protrusions may be formed of thermally stable diamond.
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