Detritus flow management features for drag bit cutters and bits so equipped

摘要

Rock detritus created by a drag bit cutter shearing subterranean formation material may flow under the cutter and attach itself to the side surface of the cutter barrel by differential pressure-induced sticking, and dilate. This attached material, confined by hydrostatic pressure, can create and strengthen a barrier between the cutter and the virgin rock being cut. The detritus barrier absorbs bit weight and reduces cutter efficiency by impairing contact of the cutter with the virgin rock formation. Increasing friction between the rock detritus and a side surface of the cutter barrel inhibits detritus flow, reduces build up, and allows hydrostatic pressure to contribute to, rather than inhibit, the cutting process. Similar beneficial results may be obtained when hydrostatic pressure drilling fluid is permitted to communicate through holes in the side surface of the cutter, or through an otherwise permeable side surface alleviating detritus sticking due to differential pressure effects.

主权项

1. A cutting element for use in subterranean drilling, the cutting element comprising, as manufactured and prior to use in subterranean drilling:
a cutter barrel comprising a supporting substrate having a superabrasive table directly secured to an end thereof; and a side surface on the cutter barrel and extending longitudinally away from a cutting edge of the superabrasive table, the side surface comprising at least one flow management feature positioned on a substrate portion of the side surface longitudinally adjacent to a diamond table portion of the side surface and configured to lift rock detritus cut by an edge of the superabrasive table from a subterranean formation away from the side surface of the cutter barrel extending substantially to the cutting edge to enable the cutting edge to directly contact subterranean formation rock by substantially equalizing, when the cutting element is used for subterranean drilling of a wellbore, hydrostatic pressure of drilling fluid immediately adjacent to the supporting substrate portion of the side surface and the superabrasive table portion of the side surface and ambient hydrostatic drilling fluid pressure in the wellbore.