| 摘要 |
Disclosed are cutter elements for a drill bits having particular, but not exclusive, application on the nose portion of the cone cutters of a rolling cone bit. T he cutter elements include a base, a cutting portion, and a plurality of cutting lobes extendin g radially from the cutting portion. Each lobe includes a forward-facing cutting face and traili ng portion having a trailing surface that intersects the cutting face in a nonlinear cutting edg e. The trailing surface is non-planar and recedes away from the cutting edge. In certain embodiments , the trailing surface is a partial dome shaped surface. The trailing portion provides strength and buttresses the cutting edge. A drill bit employing such cutter elements in the nose region of its rolling cones, either as a single element or in a circumferential row of such cutter s, will aggressively attack the core regions of the borehole bottom.
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