US20190338599A1

US20190338599A1 - Superhard cutter with spikes

Info

Publication number: US20190338599A1
Application number: US16/398,786
Authority: US
Inventors: Federico Bellin
Original assignee: Varel International Ind LLC
Current assignee: Varel International Ind LLC
Priority date: 2018-05-04
Filing date: 2019-04-30
Publication date: 2019-11-07
Also published as: CA3041701A1

Abstract

A cutter for use with a drill bit includes: a substrate for mounting in a pocket of the drill bit and made from a cermet material; and a cutting table made from a polycrystalline superhard material, mounted to the substrate, and including a set of spikes formed along at least a portion of a side of the cutting table. Each spike has an apical edge extending above a working face of the cutting table and converging toward the working face as the spike extends from the side of the cutting table across at least a portion of the working face. Each spike has a pair of base edges converging toward the apical edge as the spike extends from the side of the cutting table thereacross, thereby forming a progressively wider gap between adjacent spikes.

Description

BACKGROUND OF THE DISCLOSURE

Field of the Disclosure

The present disclosure generally relates to a superhard cutter with spikes.

Description of the Related Art

U.S. Pat. No. 4,984,642 discloses a composite tool including a sintered metal carbide support and a polycrystalline diamond active part having an inner surface of metallurgical connection to the support and an outwardly facing working surface. The working surface comprises corrugations which are substantially parallel to one another and form successive projecting zones and hollow zone on at least a part of the working surface. The composite tool is in particularly intended for drilling to a great depth, such as drilling oil wells.
U.S. Pat. No. 6,065,554 discloses a preform cutting element for a rotary drag-type drill bit comprises a front facing table of superhard material having a front surface, a peripheral surface, a rear surface bonded to a substrate of less hard material, and a cutting edge formed by at least part of the junction between the front surface and the peripheral surface. The front surface of the facing table is formed with a chip-breaking formation which is located adjacent the cutting edge and is shaped to deflect transversely of the front surface of the facing table cuttings which, in use, are removed by the cutting edge from the formation being drilled. The chip-breaking formation may comprise a peripheral groove or rebate, or an upstanding ridge or insert.
U.S. Pat. No. 8,936,115 discloses a cutting table including a cutting surface, an opposing surface, a cutting table outer wall, and one or more fins. The cutting table outer wall extends from the circumference of the opposing surface to the circumference of the cutting surface. The fins extend from a portion of the cutting surface to a portion of the cutting table outer wall. The cutting table is optionally leached prior to forming the fins. One or more fins are positioned in parallel with at least another fin in some embodiments. In some embodiments, the fins are positioned circumferentially around the cutting surface. In some embodiments, the cutting table is coupled to a substrate to form a cutter. The fins are formed either after or during the formation of the cutting table.
U.S. Pat. No. 9,175,521 discloses a cutting table including a cutting surface, an opposing surface, a cutting table outer wall, and one or more slots. The cutting table outer wall extends from the circumference of the opposing surface to the circumference of the cutting surface. The slots extend from a portion of the cutting surface to a portion of the cutting table outer wall. The cutting table is leached to form a thermally stable cutting table. One or more slots are positioned in parallel with at least another slot in some embodiments. In some embodiments, the slots are positioned circumferentially around the cutting surface. In some embodiments, at least one slot is backfilled with a backfilling material to increase heat transfer or impact resistance. In some embodiments, the cutting table is coupled to a substrate to form a cutter. The slots are formed either after or during the formation of the cutting table.
US 2016/0130881 discloses a cutting element for use with a bit including an obtuse cutting edge. The cutting edge may be formed between a cutting face and a slanted face of the cutting element. The obtuse cutting edge may be pre-formed in the cutting element for use with a bit used to mill a window in casing and/or drill a deviated borehole. The cutting element may be positioned on the bit as a trailing cutting element, and oriented to cause the obtuse cutting edge to engage casing and/or a rock formation.

SUMMARY OF THE DISCLOSURE

The present disclosure generally relates to a superhard cutter with spikes. In one embodiment, a cutter for use with a drill bit includes: a substrate for mounting in a pocket of the drill bit and made from a cermet material; and a cutting table made from a polycrystalline superhard material, mounted to the substrate, and including a set of spikes formed along at least a portion of a side of the cutting table. Each spike has an apical edge extending above a working face of the cutting table and converging toward the working face as the spike extends from the side of the cutting table across at least a portion of the working face. Each spike has a pair of base edges converging toward the apical edge as the spike extends from the side of the cutting table thereacross, thereby forming a progressively wider gap between adjacent spikes.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments.

FIGS. 1A-1D illustrate manufacture of a superhard cutter with a set of spikes and channels, according to one embodiment of the present disclosure.

FIG. 2A illustrates leaching of the cutter. FIG. 2B illustrates an alternative cutter having a second set of spikes and channels, according to another embodiment of the present disclosure. FIG. 2C illustrates a second alternative cutter having a knob for orientation thereof.

FIGS. 3A-3D illustrate the finished shaped cutter.

FIG. 4A illustrates brazing the shaped cutter into a blade of a drill bit. FIG. 4B illustrates the drill bit. FIG. 4C illustrates cutting action of the drill bit.

FIGS. 5A-5B illustrate manufacture of a third alternative superhard cutter with a set of spikes and passages, according to another embodiment of the present disclosure.

DETAILED DESCRIPTION

FIGS. 1A-1D illustrate manufacture of a superhard cutter 1 (FIG. 3A) with a set 2 of spikes 3 and channels 4, according to one embodiment of the present disclosure. Referring to FIG. 1A, the manufacturing process may commence by placement of a shear cutter 5 into a laser cutter machine 6. The shear cutter 5 may include a cylindrical cutting table 7 mounted to a cylindrical substrate 8. The cutting table and substrate may be circular-cylindrical (shown) or elliptic-cylindrical (not shown). The cutting table 8 may be made from a superhard material, such as polycrystalline diamond (PCD), and the substrate may be made from a hard material, such as a cermet, thereby forming a compact, such as a polycrystalline diamond compact. The cermet may be a cemented carbide, such as a group VIIIB metal-tungsten carbide. The group VIIIB metal may be cobalt. The shear cutter 5 may be manufactured by a high pressure, high temperature (HPHT) sintering operation using either a belt press or a cubic press.
Referring to FIG. 1B, the laser cutter machine 6 may be operated to remove selected PCD material from the cutting table 7 until the spikes 3 are formed therein 7 a. Referring to FIG. 1C, the laser cutting machine 6 may continue to remove selected PCD material from the cutting table 7 a until the channels 4 are formed between adjacent spikes 3 therein 7 b.
Referring to FIG. 1D, the cutter 5 a may be repositioned in the laser cutting machine 6 and the machine operated remove selected cermet material from the substrate 8 until a keyway 9 is formed therein 8 a for orienting the spikes 3 when mounting the cutter 1 in a drill bit 10 (FIG. 4B). The keyway 9 may be located at an edge of the substrate 8 a and may extend from a back face thereof along a portion of a side thereof. The keyway 9 may be a slot inclined relative to a longitudinal axis of the cutter 1 by an angle ranging between ten and seventy degrees. The slot may have a width corresponding to a diameter of a mating key (not shown) formed in a cutter pocket of the drill bit 10. The keyway 9 may be angularly offset from the set 2, such as being located opposite therefrom. The laser cutting machine 6 may also be operated to form a chamfer in the back face of the substrate 8 a.
Alternatively, the set 2 may be formed by using an electrical discharge machine (EDM) instead of the laser cutting machine 6. Alternatively, the keyway 9 and the chamfer may be formed by the EDM or by grinding.
FIG. 2A illustrates leaching of the cutter 5 b. The cutter 5 b may be removed from the laser cutting machine 6. A portion of the substrate 8 a and a portion of the cutting table 7 b adjacent to the substrate may be masked 11. A portion of the cutter 5 b including the cutting table 7 b and the masked portion of the substrate 8 a may then be submerged into a bath of acid 12, such as Aqua regia, and left therein for a soaking time. The soaking time may be sufficient for the acid 12 to leach at least a substantial portion of catalyst from the exposed portion of the leached cutting table 7 c. The acid 12 may penetrate into a working face 13 w and a side 13 s of the cutting table 7 c, thereby increasing a thermal stability thereof. The catalyst may be the same group VIIIB metal as the substrate.
FIG. 2B illustrates an alternative cutter 14 having a second set 15 of spikes 3 and channels 4, according to another embodiment of the present disclosure. The alternative cutter 14 may be similar to the cutter 1 except that the laser cutting machine 6 or EDM has been operated to form the second set 15 in a cutting table 14 t thereof. The second set 15 may be angularly offset from the set 2, such as located opposite to the set 2 (one-hundred eighty degrees therefrom). Further, a substrate (not shown) of the alternative cutter 14 may accordingly have a second keyway corresponding to the second set 15. Upon retrieval of a drill bit having the alternative cutters 14 from the wellbore, the drill bit may be inspected for wear. Should a wear flat be observed on any of the alternative cutters 14, the worn alternative cutter may be de-brazed from the respective cutter pocket and rotated, such as by one-hundred eighty degrees, so that the unused set 2, 15 is moved to an operative position and then the cutter re-brazed to the drill bit, thereby extending the service life of the alternative cutters 14.
Alternatively, the alternative cutter 14 may have three sets of spikes 3 and channels 4, spaced one-hundred twenty degrees apart, and a substrate thereof may have a third keyway corresponding to the third set.
FIG. 2C illustrates a second alternative cutter 16 having a knob 17 for orientation thereof. The second alternative cutter 16 may include the cutting table 7 c mounted to an alternative substrate 16 s. The alternative substrate 16 s may have the knob 17 mounted to a back face 16 b thereof for orienting the set 2 of spikes 3 and channels 4. The alternative substrate 16 s may be similar to the substrate 8 a except for having the knob 17 mounted thereto instead of the keyway 9 formed therein. The knob 17 may be formed separately from the rest of the second alternative cutter 16 and then mounted to the substrate 16 s thereof, such as by brazing. The knob 17 may be angularly offset from the set 2, such as being located opposite therefrom (one-hundred eighty degrees therefrom). The knob 17 may be hemi-spherical and have a diameter ranging between twenty-five and forty-five percent of a diameter of the back face 16 b. Instead of a key, the drill bit 10 may have a dimple (not shown) formed in the cutter pocket thereof for mating with the knob, thereby ensuring that the second alternative cutter 16 has been properly oriented to the operative position. The knob 17 may be made from the same material as the substrate or a different material than the substrate, such as a metal or alloy, such as steel.
Alternatively, the second alternative cutter 16 may include the alternative cutting table 14 t and the second alternative cutter may further include a second knob (not shown) mounted to the back face 17 b of the alternative substrate 16 s for orienting the second set 15. Alternatively, the knob 17 may be formed integrally with the alternative substrate 16 s.
FIGS. 3A-3D illustrate the finished shaped cutter 1. The set 2 may include the plurality of the spikes 3 (ten shown) and the plurality of the channels 4 (nine shown) formed between adjacent spikes. Each spike 3 may have a triangular front face, such as isosceles, forming a portion of the side 13 s of the cutting table 7 c. Each spike 3 may extend above the working face 13 w of the cutting table 7 c to an apical edge 3 a. Each apical edge 3 a may have a maximum height at the side 13 s and each apical edge may converge toward the working face 13 w at an angle 18 as the respective spike 3 extends from the side 13 s across the working face 13 w. Each apical edge 3 a may be parallel with the rest of the apical edges of the set 2. Each apical edge 3 a may be slightly truncated to form a flat or may be rounded. The flat may a width ranging between twenty and one hundred fifty microns and the round may have a radius equal to one-half the width of the flat.
Each spike 3 may also have a pair of base edges 3 b and each base edge may converge toward the respective apical edge 3 a as the respective spike extends from the side 13 s across the working face 13 w, thereby resulting in each spike having a maximum width at the side. The inclined apical edge 3 a and the converging base edges 3 b may create a progressively wider gap between adjacent spikes 3 as the adjacent spikes extend from the side 13 s across the working face 13 w. The progressively wider gap may facilitate cuttings removal from the spikes 3 as the cutter 1 engages a rock formation 19 (FIG. 4C). The inclined apical edge 3 a and the converging base edges 3 b may result in each spike having triangular side faces.
Each channel 4 may have a rectangular mouth formed in the side 13 s. A floor of each channel may extend below the working face 13 w to a maximum depth at the side 13 s and a floor of each channel may converge toward the working face 13 w at an angle (not shown) as the respective channel extends across the working face. Each channel 4 may serve to transport the leaching acid 12 into the cutting table 7 c, thereby increasing penetration of the acid 12 therein. A width of each channel 4 may be sized to create capillary action during leaching of the cutting table 7 c and may range between fifty and three hundred microns. Each channel 4 may be parallel with the rest of the channels of the set 2 and with the apical edges 3 a of the set.
The set 2 may be formed along a portion of the side 13 s, such as between one-quarter to one-half of a circumference thereof. The set 2 may extend from the side 13 s and across a portion of the working face 13 w by a distance ranging between one-eighth and one-half of a diameter of the working face. A maximum height of the spikes 3 may vary along the set 2, such as having a parabolic distribution along the set with the tallest spike(s) at the center of the set and the shortest spikes at the periphery of the set. A maximum width of the spikes 3 may vary in accordance with the maximum height of the spikes 3 and the tallest spike(s) may have a maximum width corresponding to a spacing between adjacent channels. A maximum height of the tallest spike(s) 3 may range between one-half and three millimeters.
A depth of the channels 4 may vary along the set 2, such as having a parabolic distribution along the set with the deepest channel(s) at the center of the set and the shallowest channels at the periphery of the set. A maximum depth of the deepest channel(s) 4 may be limited to ensure a buffer 20 is maintained between the channel(s) and an interface 21 between the cutting table 7 c and the substrate 8 a. The depth of the channels 4 may correspond to the height of the adjacent spikes 3. The buffer 20 may have a height from the interface 21 ranging between one-half and one millimeter. A spacing between adjacent channels 4 may be uniform for the set and may range between one-half and five millimeters. A spacing in a lesser portion of the range may ensure that a foundation portion of the cutting table 7 c adjacently below each spike 3 beneath each spike is completely leached; however, a spacing in the greater portion of the range may be more advantageous for tougher rock formations.
Alternatively, a maximum height of the spikes 3 and/or a maximum depth of the channels 4 may be uniform. Alternatively, the channels 4 may be filled after leaching with a ceramic, such as molybdenum carbide, titanium carbide, vanadium carbide, iron carbide, nickel carbide, niobium carbide, and tungsten carbide. Alternatively, each apical edge 3 a may be sharp or may include a pair of inclined surfaces.
FIG. 4A illustrates brazing the shaped cutter 1 into a blade 22 of a drill bit 10. The brazing operation may be manual or automated. A plurality of the cutters 1 may be mounted into pockets formed in a leading edge of the blade 22. Each shaped cutter 1 may be delivered to the pocket by an articulator 23. The articulator 23 may retain the cutter 1 only partially in the pocket such that the keyway 9 and key do not engage.
Once delivered, a brazing material 24 may be applied to an interface formed between the respective pocket and the shaped cutter 1 using an applicator 22. As the brazing material 24 is being applied to the interface, the articulator 23 may rotate the shaped cutter 1 relative to the pocket to distribute the brazing material 20 throughout the interface. The articulator 23 may then be operated to align the keyways 9 with the key and engage the aligned members, thereby ensuring that the shaped cutter 1 is properly oriented to the operative position. The operative position may be where the apical edge 3 a of the tallest peak(s) 3 is perpendicular to a projection (not shown) of the leading edge of the respective blade 22 through the leading cutter pocket.
A heater (not shown) may be operated to melt the brazing material 24. Cooling and solidification of the brazing material 24 may mount the shaped cutter 1 to the blade 22. The brazing operation may then be repeated for mounting additional shaped cutters 1 into additional pockets formed along the leading edge of the blade 22. The pocket may be inclined relative to a bottom face of the blade adjacent thereto by a back rake angle 25 (FIG. 4C).
FIG. 4B illustrates the drill bit 10. The drill bit 10 may include a bit body 26, a shank 27, a cutting face, and a gage section 28. A lower portion of the bit body 26 adjacent to the cutting face may be made from a composite material, such as a ceramic and/or cermet body powder infiltrated by a metallic binder and an upper portion of the bit body adjacent to the shank 27 may be made from a softer material than the composite material of the upper portion, such as a metal or alloy shoulder powder infiltrated by the metallic binder. The bit body 26 may be mounted to the shank 27 during molding thereof. The shank 27 may be tubular and made from a metal or alloy, such as steel, and have a coupling, such as a threaded pin, formed at an upper end thereof for connection of the drill bit 10 to a drill collar (not shown). The shank 27 may have a flow bore formed therethrough and the flow bore may extend into the bit body 26 to a plenum thereof. The cutting face may form a lower end of the drill bit 10 and the gage section 28 may form an outer portion thereof.
Alternatively, the bit body 26 may be metallic, such as being made from steel, and may be hardfaced. The metallic bit body may be connected to a modified shank by threaded couplings and then secured by a weld or the metallic bit body may be monoblock having an integral body and shank.
The cutting face may include one or more primary blades 22 p, one or more secondary blades 22 s, fluid courses formed between the blades, the leading cutters 1, and backup cutters 5. The cutting face may have one or more sections, such as an inner cone, an outer shoulder, and an intermediate nose between the cone and the shoulder sections. The blades 22 may be disposed around the cutting face and each blade may be formed during molding of the bit body 26 and may protrude from a bottom of the bit body. The primary blades 22 p and the secondary blades 22 s may be arranged about the cutting face in an alternating fashion. The primary blades 22 p may each extend from a center of the cutting face, across the cone and nose sections, along the shoulder section, and to the gage section 28. The secondary blades 22 s may each extend from a periphery of the cone section, across the nose section, along the shoulder section, and to the gage section 28.
Each blade 22 may extend generally radially across the cone (primary only) and nose sections with a slight spiral curvature and along the shoulder section generally longitudinally with a slight helical curvature. Each blade 22 may be made from the same material as the bit body 26. The leading cutters 1 may be mounted into the pockets along leading edges of the blades 22 and the backup cutters 5 may be mounted into pockets adjacent to trailing edges of the blades. The backup cutters 5 may be omitted from the cone sections of the primary blades 22 p. One of the leading cutters in each blade 22 adjacent to the gage section 28 may be the shear cutter 5 (shown) or the shaped cutter 1 (not shown).
One or more ports 29 may be formed in the bit body 26 and each port may extend from the plenum and through the bottom of the bit body to discharge drilling fluid (not shown) along the fluid courses. Once the cutters 1 have been mounted to the respective blades 22, a nozzle (not shown) may be inserted into the each port 29 and mounted to the bit body 26, such as by screwing the nozzle therein.
The gage section 28 may define a gage diameter of the drill bit 10. The gage section 28 may include a plurality of gage pads, such as one gage pad for each blade 22 and junk slots formed between the gage pads. The junk slots may be in fluid communication with the fluid courses formed between the blades 22. The gage pads may be disposed around the gage section 28 and each pad may be formed during molding of the bit body 26 and may protrude from the outer portion of the bit body. Each gage pad may be made from the same material as the bit body 26 and each gage pad may be formed integrally with a respective blade 22. Each gage pad may extend upward from a shoulder portion of the respective blade 22 to an exposed outer surface of the shank 27.
FIG. 4C illustrates cutting action of the drill bit 10. In use (not shown), the drill bit 10 may be assembled with one or more drill collars, such as by threaded couplings, thereby forming a bottomhole assembly (BHA). The BHA may be connected to a bottom of a pipe string, such as drill pipe or coiled tubing, thereby forming a drill string. The BHA may further include a steering tool, such as a bent sub or rotary steering tool, for drilling a deviated portion of the wellbore. The pipe string may be used to deploy the BHA into the wellbore. The drill bit 10 may be rotated, such as by rotation of the drill string from a rig (not shown) and/or by a drilling motor (not shown) of the BHA, while drilling fluid, such as mud, may be pumped down the drill string. A portion of the weight of the drill string may be set on the drill bit 10. The drilling fluid may be discharged by the nozzles and carry cuttings up an annulus formed between the drill string and the wellbore and/or between the drill string and a casing string and/or liner string.
The inclination angle 18 of each cutter 1 may correspond to a back rake angle 25 of the cutters 1, 5 such that the apical edges 3 a may be perpendicular or substantially perpendicular to the rock formation 19 engaged by the spikes 3 during drilling. Each of the inclination angle 18 and the back rake angle 25 may range between ten and thirty degrees. As the drill bit 10 engages the rock formation 19 adjacent to the wellbore, each leading cutter 1 may gouge and/or crush 30 the formation, thereby facilitating subsequent shear cutting by the respective backup cutter 5.
FIGS. 5A-5B illustrate manufacture of a third alternative superhard cutter 31 with a set of spikes 3 and passages 32, according to another embodiment of the present disclosure. Referring to FIG. 5A, the manufacturing process may commence by placement of the shear cutter 5 into the laser cutter machine 6 (see FIG. 1A). The laser cutter machine 6 may be operated to remove selected PCD material from the cutting table 7 until the spikes 3 are formed therein 33 a. Instead of the channels 4, the laser cutting machine 6 may be positioned and operated to bore a leaching passage 32 underneath each spike 3 from the working face 13 w to the side 13 s of the cutting table 33 a.
Each leaching passage 32 may have a front port at the working face 13 w of the cutting table 33 and a side port 32 s at the side 13 s thereof. Each leaching passage 32 may extend outward and backward from the front port to the side port 32 s. A depth of the side ports 32 s may be uniform along the set. A maximum depth of the side ports 32 s may be limited to ensure that the buffer 20 is maintained between the leaching passages 32 and the interface between the cutting table 33 a and the substrate 8 a. The depth of the side ports 32 s may correspond to the height of the tallest spike 3. The location of each front port may correspond to an inner end of the respective spike 3. An inclination angle of each leaching passage 32 relative to the working face 13 w may range between five degrees and forty-five degrees. A diameter of each leaching passage 32 may range between one hundredth of a millimeter and one millimeter.
Alternatively, the depth of the side ports 32 s may vary with the height of the spikes 3 along the set similar to the channels 4. Alternatively, the depth of the side ports 32 s may be uniform at a depth corresponding to the height of any of the spikes 3 in the set.
The third alternative superhard cutter 31 may be repositioned in the laser cutting machine 6 and the machine operated remove selected cermet material from the substrate 8 until the keyway 9 and chamfer are formed therein 8 a (or alternatives discussed above).
Referring to FIG. 5B, the third alternative superhard cutter 31 may be removed from the laser cutting machine 6. A portion of the substrate 8 a and a portion of the cutting table 33 a adjacent to the substrate may be masked 11. A portion of the third alternative superhard cutter 31 including the cutting table 33 a and the masked portion of the substrate 8 a may then be submerged into the bath of acid 12 and left therein for a soaking time. The soaking time may be sufficient for the acid 12 to leach at least a substantial portion of catalyst from the exposed portion of the leached cutting table 33 b. Leaching is facilitated by the inclusion of the leaching passages 32.
Alternatively, the third alternative superhard cutter 31 may include a second (or more) set of spikes, as discussed above for the alternative cutter 14. Additionally, a plurality of the third alternative superhard cutters 31 may be used with the drill bit 10 instead of the shaped cutters 1.
While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope of the invention is determined by the claims that follow.

Claims

1. A cutter for use with a drill bit, comprising:

a substrate for mounting in a pocket of the drill bit and made from a cermet material; and

a cutting table made from a polycrystalline superhard material, mounted to the substrate, and comprising a set of spikes formed along at least a portion of a side of the cutting table,

wherein:

each spike has an apical edge extending above a working face of the cutting table and converging toward the working face as the spike extends from the side of the cutting table across at least a portion of the working face, and

each spike has a pair of base edges converging toward the apical edge as the spike extends from the side of the cutting table thereacross, thereby forming a progressively wider gap between adjacent spikes.

2. The cutter of claim 1, wherein:

the set further comprises a plurality of channels formed in the side of the cutting table,

each channel is formed between adjacent spikes, and

a width of each channel is sized to induce capillary action of leaching acid.

3. The cutter of claim 2, wherein a floor of each channel converges toward the working face as the channel extends from the side of the cutting table thereacross.

4. The cutter of claim 3, wherein a maximum depth of the channels varies along the set.

5. The cutter of claim 4, wherein a deepest one or more of the channels is located at a center of the set and shallowest ones of the channels are located at the periphery of the set.

6. The cutter of claim 1, wherein each apical edge is parallel with the rest of the apical edges of the set.

7. The cutter of claim 1, wherein the set extends across the working face by a distance ranging between one-eighth and one-half of a diameter of the working face.

8. The cutter of claim 1, wherein a maximum height of the spikes varies along the set.

9. The cutter of claim 8, wherein a tallest one or more of the spikes is located at a center of the set and shortest ones of the spikes are located at the periphery of the set.

10. The cutter of claim 8, wherein a tallest one or more of the spikes has a height ranging between one-half and three millimeters.

11. The cutter of claim 1, wherein the set of spikes extends along the side for a distance ranging between one-quarter to one-half of a circumference of the side.

12. The cutter of claim 11, wherein the substrate has a keyway formed in an edge thereof for orienting the set of spikes.

13. The cutter of claim 11, wherein the substrate has a bump formed in or mounted to a back face thereof for orienting the set of spikes.

14. The cutter of claim 11, wherein the cutting table further comprises a second set of spikes formed along a second portion of the side of the cutting table.

15. The cutter of claim 1, wherein:

the set further comprises a plurality of leaching passages, and

each leaching passage extends underneath a respective spike.

16. The cutter of claim 15, wherein each leaching passage has a front port at the working face of the cutting table and a side port at the side of the cutting table.

17. The method of claim 16, wherein a depth of each side port corresponds to a height of one of the spikes.

18. The cutter of claim 15, wherein a diameter of each leaching passage ranges between 0.01 mm and 1 mm.

19. The method of claim 15, wherein an inclination angle of each leaching passage relative to the working surface of the cutting table ranges between 5 degrees and 45 degrees.

20. A bit for drilling a wellbore, comprising:

a shank having a coupling formed at an upper end thereof;

a body mounted to a lower end of the shank; and

a cutting face forming a lower end of the bit and comprising:

a blade protruding from the body; and

the cutter of claim 1,

wherein:

the substrate is mounted in the pocket formed in the blade at a back rake angle, and

an inclination angle of each apical edge corresponds to the back rake angle such that the interface is perpendicular or substantially perpendicular to a rock formation engaged by the spikes during drilling.