Drill bit cutter elements and drill bits including same

1. A cutter element for a drill bit configured to drill a borehole in a subterranean formation, the cutter element comprising:

a base portion having a central axis, a first end, a second end, and a radially outer cylindrical surface extending axially from the first end to the second end;

a cutting layer fixably mounted to the first end of the base portion, wherein the cutting layer includes a cutting face distal the base portion and a radially outer cylindrical surface extending axially from the cutting face to the radially outer cylindrical surface of the base portion, wherein the radically outer cylindrical surface of the cutting layer is contiguous with the radially outer cylindrical surface of the base portion;

wherein the cutting face comprises:

an elongate raised ridge extending across the cutting face, wherein the raised ridge has a first end at the radially outer surface of the cutting layer and a second end at the radially outer cylindrical surface of the cutting layer, and wherein the raised ridge defines a maximum height of the cutter element measured axially from the second end of the base portion to the cutting face;

a first planar lateral side surface extending from the raised ridge to the radially outer cylindrical surface of the cutting layer; and

a second planar lateral side surface extending from the raised ridge to the radially outer cylindrical surface of the cutting layer;

wherein the raised ridge of the cutting face comprises a central surface, a cutting surface extending radially from the central surface toward the radially outer cylindrical surface of the cutting layer, and a relief surface extending radially from the central surface toward the radically outer cylindrical surface, wherein the central surface is planar;

wherein the central surface has a length L measured from a first intersection of the central surface and the cutting surface to a second intersection of the central surface and the relief surface in top view;

wherein the central surface has a width W measured from a third intersection of the central surface and the first planar lateral side surface to a fourth intersection of the central surface and the second planar lateral side surface in top view;

wherein the ratio of the length L to a diameter of the base portion is between 0.10 and 0.90; and

wherein an aspect ratio of the central surface equal to the ratio of the length L to the width W is between 0.10 and 30.0.

2. The cutter element of claim 1 , wherein each planar lateral side surface extends axially toward the base portion moving from the raised ridge toward the radially outer cylindrical surface of the cutting layer.

3. The cutter element of claim 2 , wherein each planar lateral side surface is oriented at an angle α relative to a reference plane oriented perpendicular to the central axis, wherein each angle α ranges from 5° to 25°.

4. The cutter element of claim 3 , wherein the angle α between the first planar lateral side surface and the reference plane is equal to the angle α between the second planar lateral side surface and the reference plane.

5. The cutter element of claim 1 , wherein the central surface is oriented perpendicular to the central axis.

6. The cutter element of claim 5 , wherein the central surface is radially centered on the cutting face.

7. The cutting element of claim 5 , wherein the central surface is rectangular.

8. The cutting element of claim 1 , wherein the cutting surface is planar and the relief surface is planar.

9. The cutting element of claim 8 , wherein the cutting surface is oriented at an acute angle β relative to a reference plane oriented perpendicular to the central axis, and wherein the relief surface is oriented at an acute angle θ relative to the reference plane oriented perpendicular to the central axis, wherein the angle β ranges from 1° to 20° and the angle θ ranges from 1° to 20°.

10. The cutting element of claim 8 , wherein the cutting surface slopes axially toward the base portion moving radially outward from the central surface toward the radially outer cylindrical surface of the cutting layer and the relief surface slopes axially toward the base portion moving radially outward from the central surface toward the radially outer cylindrical surface of the cutting layer.

11. The cutting element of claim 1 , wherein the cutting surface is continuously curved and concave or convex between the central surface and the radially outer cylindrical surface of the cutting layer and the relief surface is continuously curved and concave or convex between the central surface and the radially outer cylindrical surface of the cutting layer.

12. The cutter element of claim 1 , further comprising:

a first planar flat extending from the cutting face along the radially outer cylindrical surface of the cutting layer into the radially outer cylindrical surface of the base portion;

a second planar flat extending from the cutting face along the radially outer cylindrical surface of the cutting layer into the radially outer cylindrical surface of the base portion, wherein the first planar flat and the second planar flat are circumferentially spaced part.

13. The cutter element of claim 12 ,

wherein the first planar flat extends circumferentially along a portion of the first planar lateral side surface and a portion of the cutting surface;

wherein the second planar flat extends circumferentially along a portion of the second planar lateral side surface and a portion of the cutting surface.

14. The cutter element of claim 12 , wherein the first planar flat is oriented perpendicular to a first reference plane containing the central axis and the second planar flat is oriented perpendicular to a second reference plane containing the central axis;

wherein the first reference plane and the second reference plane are angularly spaced apart about the central axis by an angle μ that ranges from 70° to 120°.

15. The cutter element of claim 14 , wherein each planar flat slopes radially outward moving axially from the cutting face into the base portion.

16. The cutter element of claim 15 , wherein the first planar flat is oriented at an angle σ 1 relative to the central axis as measured in the first reference plane and the second planar flat is oriented at an angle σ 2 relative to the central axis as measured in the second reference plane, wherein the angle σ 1 ranges from 2° to 10° and the angle σ 2 ranges from 2° to 10°.

17. The cutter element of claim 16 , wherein the cutting face is symmetric about a reference plane containing the central axis and bisecting the raised ridge.

18. A cutter element for a drill bit configured to drill a borehole in a subterranean formation, the cutter element comprising:

a base portion having a central axis, a first end, a second end, and a radially outer cylindrical surface extending axially from the first end to the second end;

a cutting layer fixably mounted to the first end of the base portion, wherein the cutting layer includes a cutting face distal the base portion and a radially outer cylindrical surface extending axially from the cutting face to the radially outer cylindrical surface of the base portion, wherein the radically outer cylindrical surface of the cutting layer is contiguous with the radially outer cylindrical surface of the base portion;

wherein the cutting face comprises:

an elongate raised ridge extending across the cutting face, wherein the raised ridge has a first end at the radially outer surface of the cutting layer and a second end at the radially outer cylindrical surface of the cutting layer, and wherein the raised ridge defines a maximum height of the cutter element measured axially from the second end of the base portion to the cutting face;

a first planar lateral side surface extending from the raised ridge to the radially outer cylindrical surface of the cutting layer; and

a second planar lateral side surface extending from the raised ridge to the radially outer cylindrical surface of the cutting layer

wherein the raised ridge of the cutting face comprises a central surface, a cutting surface extending radially from the central surface toward the radially outer cylindrical surface of the cutting layer, and a relief surface extending radially from the central surface toward the radially outer cylindrical surface, wherein the cutting surface is planar and the relief surface is planar;

wherein the central surface is continuously curved and convex or concave between the cutting surface and the relief surface;

wherein the central surface has a length L measured from a first intersection of the central surface and the cutting surface to a second intersection of the central surface and the relief surface in top view;

wherein the central surface has a width W measured from a third intersection of the central surface and the first planar lateral side surface to a fourth intersection of the central surface and the second planar lateral side surface in top view;

wherein the ratio of the length L to a diameter of the base portion is between 0.10 and 0.90; and

wherein an aspect ratio of the central surface equal to the ratio of the length L to the width W is between 0.10 and 30.0.

19. The cutter element of claim 18 , wherein each planar lateral side surface extends axially toward the base portion moving from the raised ridge toward the radially outer cylindrical surface of the cutting layer.

20. The cutter element of claim 19 , wherein each planar lateral side surface is oriented at an angle α relative to a reference plane oriented perpendicular to the central axis, wherein each angle α ranges from 5° to 25°.

21. The cutter element of claim 20 , wherein the angle α between the first planar lateral side surface and the reference plane is equal to the angle α between the second planar lateral side surface and the reference plane.

22. The cutter element of claim 18 , wherein the central surface is radially centered on the cutting face.

23. The cutting element of claim 18 , wherein the central surface is rectangular.

24. The cutting element of claim 18 , wherein the cutting surface is oriented at an acute angle β relative to a reference plane oriented perpendicular to the central axis, and wherein the relief surface is oriented at an acute angle θ relative to the reference plane oriented perpendicular to the central axis, wherein the angle β ranges from 1° to 20° and the angle θ ranges from 1° to 20°.

25. The cutting element of claim 18 , wherein the cutting surface slopes axially toward the base portion moving radially outward from the central surface toward the radially outer cylindrical surface of the cutting layer and the relief surface slopes axially toward the base portion moving radially outward from the central surface toward the radially outer cylindrical surface of the cutting layer.

26. The cutter element of claim 18 , further comprising:

a first planar flat extending from the cutting face along the radially outer cylindrical surface of the cutting layer into the radially outer cylindrical surface of the base portion;

a second planar flat extending from the cutting face along the radially outer cylindrical surface of the cutting layer into the radially outer cylindrical surface of the base portion, wherein the first planar flat and the second planar flat are circumferentially spaced part.

27. The cutter element of claim 26 , wherein the first planar flat extends circumferentially along a portion of the first planar lateral side surface and a portion of the cutting surface;

wherein the second planar flat extends circumferentially along a portion of the second planar lateral side surface and a portion of the cutting surface.

28. The cutter element of claim 26 , wherein the first planar flat is oriented perpendicular to a first reference plane containing the central axis and the second planar flat is oriented perpendicular to a second reference plane containing the central axis;

wherein the first reference plane and the second reference plane are angularly spaced apart about the central axis by an angle μ that ranges from 70° to 120°.

29. The cutter element of claim 28 , wherein each planar flat slopes radially outward moving axially from the cutting face into the base portion.

30. The cutter element of claim 29 , wherein the first planar flat is oriented at an angle σ 1 relative to the central axis as measured in the first reference plane and the second planar flat is oriented at an angle σ 2 relative to the central axis as measured in the second reference plane, wherein the angle σ 1 ranges from 2° to 10° and the angle σ 2 ranges from 2° to 10°.

31. The cutter element of claim 30 , wherein the cutting face is symmetric about a reference plane containing the central axis and bisecting the raised ridge.

32. A cutter element for a drill bit configured to drill a borehole in a subterranean formation, the cutter element comprising:

a base portion having a central axis, a first end, a second end, and a radially outer cylindrical surface extending axially from the first end to the second end;

a cutting layer fixably mounted to the first end of the base portion, wherein the cutting layer includes a cutting face distal the base portion and a radially outer cylindrical surface extending axially from the cutting face to the radially outer cylindrical surface of the base portion, wherein the radically outer cylindrical surface of the cutting layer is contiguous with the radially outer cylindrical surface of the base portion;

wherein the cutting face comprises:

a planar central region;

a planar cutting region extending radially from the planar central region to the radially outer surface of the cutting layer;

a planar relief region extending radially from the planar central region to the radially outer surface of the cutting layer;

a first planar lateral side region extending laterally from the planar central region, the planar cutting region, and the planar relief region to the radially outer surface of the cutting layer; and

a second planar lateral side region extending laterally from the planar central region, the planar cutting region, and the planar relief region to the radially outer surface of the cutting layer;

wherein the first planar lateral side region slopes axially downward moving laterally from the planar central region, the planar cutting region, and the planar relief region toward the radially outer surface of the cutting layer;

wherein the second planar lateral side region slopes axially downward moving laterally from the planar central region, the planar cutting region, and the planar relief region to the radially outer surface of the cutting layer;

wherein the planar cutting region is circumferentially positioned between the first planar lateral side region and the second planar lateral side region;

wherein the planar relief region is circumferentially positioned between the first planar lateral side region and the second planar lateral side region;

wherein the planar central region is disposed between the first planar lateral side region and the second planar lateral side region;

wherein the planar central region has a length L measured from a first intersection of the planar central region and the planar cutting region to a second intersection of the planar central region and the planar relief region in top view;

wherein the planar central region has a width W measured from a third intersection of the planar central region and the first planar lateral side surface to a fourth intersection of the planar central region and the second planar lateral side surface in top view;

wherein the ratio of the length L to a diameter of the base portion is between 0.10 and 0.90; and

wherein an aspect ratio of the planar central region equal to the ratio of the length L to the width W is between 0.10 and 30.0.

33. The cutter element of claim 32 , wherein the planar central region is oriented perpendicular to the central axis.

34. The cutter element of claim 33 , wherein each planar lateral side region is oriented at an angle α relative to a reference plane oriented perpendicular to the central axis, wherein each angle α ranges from 5° to 25°.

35. The cutter element of claim 34 , wherein the angle α between the first planar lateral side region and the reference plane is equal to the angle α between the second planar lateral side region and the reference plane.

36. The cutting element of claim 34 , wherein the planar cutting region is oriented at an acute angle β relative to the reference plane and the planar relief region is oriented at an acute angle θ relative to the reference plane, wherein the angle β ranges from 1° to 20° and the angle θ ranges from 1° to 20°.

37. The cutter element of claim 32 , wherein the planar central region is radially centered on the cutting face.

38. The cutting element of claim 37 , wherein the planar central region is rectangular.

39. The cutting element of claim 32 , wherein the planar cutting region slopes axially toward the base portion moving radially outward from the central region to the radially outer surface of the cutting layer and the planar relief region slopes axially toward the base portion moving radially outward from the planar central region to the radially outer surface of the cutting layer.

40. The cutter element of claim 32 , wherein the radially outer surface of the base portion is cylindrical and the radially outer surface of the cutting layer is cylindrical.

41. The cutter element of claim 40 , further comprising:

a first planar flat extending from the cutting face along the radially outer surface of the cutting layer into the radially outer surface of the base portion;

a second planar flat extending from the cutting face along the radially outer surface of the cutting layer into the radially outer surface of the base portion, wherein the first planar flat and the second planar flat are circumferentially spaced part.

42. The cutter element of claim 41 , wherein the first planar flat extends circumferentially along a portion of the first planar lateral side surface and a portion of the planar cutting surface;

wherein the second planar flat extends circumferentially along a portion of the second planar lateral side surface and a portion of the planar cutting surface.

43. The cutter element of claim 41 , wherein the first planar flat is oriented perpendicular to a first reference plane containing the central axis and the second planar flat is oriented perpendicular to a second reference plane containing the central axis;

wherein the first reference plane and the second reference plane are angularly spaced apart about the central axis by an angle μ that ranges from 70° to 120°.

44. The cutter element of claim 43 , wherein each planar flat slopes radially outward moving axially from the cutting face into the base portion.

45. The cutter element of claim 44 , wherein the first planar flat is oriented at an angle σ 1 relative to the central axis as measured in the first reference plane and the second planar flat is oriented at an angle σ 2 relative to the central axis as measured in the second reference plane, wherein the angle σ 1 ranges from 2° to 10° and the angle σ 2 ranges from 2° to 10°.

46. The cutter element of claim 32 , wherein the cutting face is symmetric about a reference plane containing the central axis and bisecting the planar central region, the planar cutting region, and the planar relief region.