Patent ID: 7000715

Claim:
A rotary drag bit for drilling a subterranean formation, comprising: a bit body having a longitudinal axis and extending radially outward therefrom to a gage, the bit body further comprising at least a first region, a second region, and a third region, radially intermediate the first and second regions, extending over a face of the bit body to be oriented toward the subterranean formation during drilling; and a plurality of cutters located on the bit body in the first, second, and third regions, the cutters each comprising a superabrasive cutting face of a preselected geometry and including a preselected effective cutting face backrake angle with respect to a line generally perpendicular to the subterranean formation, as taken in the direction of intended bit rotation, and wherein the respective superabrasive cutting faces of a majority of cutters located in the first region exhibit substantially more negative effective cutting face backrake angles than the effective cutting face backrake angles of the respective superabrasive cutting faces of a majority of cutters located in the second and third regions.