| 摘要 |
Cutting elements providing a relatively constant superabrasive area in contact with the formation responsive to weight on bit during a substantial portion of the useful life of a circular cutting face cutting element or other cutting element exhibiting a non-linear cutting edge, for example, from about 5% diametrical wear to in excess of about 30% diametrical wear in the case of a circular cutting element, measured across the cutting face. The superabrasive table of the cutting element is configured, internally, externally, or both, to vary in depth radially and laterally, as required, so that an increase in width of the contact or wear flat area with the formation and the variation in table depth as the cutting element wears, are substantially offsetting. The rate of penetration of a drill bit so equipped may thus be maintained at a desirable magnitude without a substantial increase in weight on bit as the cutting element wears, since the superabrasive contact area is maintained relatively constant.
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