| 摘要 |
In one aspect, a cutting structure for a drill bit includes cutters arranged to form a cutter profile. Substantially all of the cutters in a shoulder section of the cutter profile are positioned at a profile angle of at most 65°. In another aspect, substantially all of the shoulder cutters are arranged so that the longitudinal force exerted by each shoulder cutter onto an earthen formation is at least 25 percent of the normal force exerted by the shoulder cutter onto the earthen formation.
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