Earth-boring tools having shaped cutting elements
View Patent ↗Cutting elements include a volume of superabrasive material. The volume of superabrasive material comprises a front-cutting surface, an end-cutting surface, a cutting edge, and lateral side surfaces extending between and intersecting each of the front-cutting surface and the end-cutting surface. An earth-boring tool may comprise a bit body and at least one cutting element attached to the bit body. Methods of forming cutting elements comprise forming a volume of superabrasive material comprising forming a front-cutting surface, an end-cutting surface, a cutting edge, and lateral side surfaces extending between and intersecting each of the front-cutting surface and the end-cutting surface. Methods of forming earth-boring tools comprise forming a cutting element and attaching the cutting element to an earth-boring tool.
1. A fixed-cutter bit, comprising:
a fixed-cutter bit body having a plurality of blades; and
at least one cutting element attached to a blade of the fixed-cutter bit body, the at least one cutting element comprising:
a substrate; and
a volume of superabrasive material bonded to the substrate at an interface, the volume of superabrasive material comprising:
an end cutting surface;
a first side chamfer surface;
a second side chamfer surface;
a lateral side cutting surface intersecting each of the first side chamfer surface and the second side chamfer surface; and
a cutting edge at an intersection of the end cutting surface and the lateral side cutting surface;
wherein the at least one cutting element is oriented on the blade such that a portion of the lateral side cutting surface contacts a point on an exposed surface of a subterranean formation before any portion of the end cutting surface contacts the point on the exposed surface when the fixed-cutter bit body is rotated within a wellbore.
2. The fixed-cutter bit of claim 1 , wherein the at least one cutting element exhibits an effective positive back rake angle.
3. The fixed-cutter bit of claim 1 , wherein the end cutting surface intersects each of the first side chamfer surface and the second side chamfer surface.
4. The fixed-cutter bit of claim 3 , wherein the end cutting surface is substantially planar.
5. The fixed-cutter bit of claim 4 , wherein the end-cutting surface is oriented at an acute angle greater than zero degrees (0°) and less than ninety degrees (90°) relative to a longitudinal axis of the cutting element, the longitudinal axis defined as an axis normal to a surface of the cutting element opposite the end-cutting surface.
6. The fixed-cutter bit of claim 1 , wherein the at least one cutting element is generally cylindrical.
7. The fixed-cutter bit of claim 1 , wherein the first side chamfer surface is discontinuous from the second side chamfer surface.
8. The fixed-cutter bit of claim 1 , wherein the at least one cutting element is secured to a leading edge of the blade.
9. The fixed-cutter bit of claim 1 , wherein the at least one cutting element comprises at least one polished surface.
10. The fixed-cutter bit of claim 1 , wherein at least a portion of the lateral side cutting surface is frustoconical.
11. The fixed-cutter bit of claim 1 , wherein at least a portion of the lateral side cutting surface is cylindrical.
12. The fixed-cutter bit of claim 1 , wherein at least one of the first side chamfer surface and the second side chamfer surface is substantially planar.
13. The fixed-cutter bit of claim 1 , wherein the first side chamfer surface and the second side chamfer surface have mirror-image geometries.
14. The fixed-cutter bit of claim 1 , wherein at least a portion of the end cutting surface exhibits a linear profile in a plane extending longitudinally through the at least one cutting element, the plane extending along a longitudinal axis of the at least one cutting element and intersecting the portion of the cutting edge most distal from the interface.
15. The fixed-cutter bit of claim 14 , wherein the linear profile of the at least a portion of the end cutting surface is oriented at an acute angle relative to the longitudinal axis of the cutting element.
16. A fixed-cutter bit, comprising:
a fixed-cutter bit body having a plurality of blades; and
at least one cutting element attached to a blade of the fixed-cutter bit body, the at least one cutting element comprising:
a volume of superabrasive material, comprising:
an end cutting surface;
a first side chamfer surface;
a second side chamfer surface;
a lateral side cutting surface intersecting each of the first side chamfer surface and the second side chamfer surface; and
a cutting edge at an intersection of the end cutting surface and the lateral side cutting surface;
a base surface; and
a longitudinal axis extending through the cutting surface and the base surface, wherein the longitudinal axis is perpendicular to the base surface;
wherein the at least one cutting element is oriented such that a portion of the lateral side cutting surface contacts a point on an exposed surface of a subterranean formation before any portion of the end cutting surface contacts the point on the exposed surface when the fixed-cutter bit body is rotated within a wellbore.