CUTTING INSERTS FOR USE IN A DOWNHOLE BIT AND METHODS THEROF

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application No. 63/634923 filed on 16 Apr. 2024, which is incorporated herein by reference in its entirety.

BACKGROUND OF THE DISCLOSURE

Wellbores may be drilled into a surface location or seabed for a variety of exploratory or extraction purposes. For example, a wellbore may be drilled to access fluids, such as liquid and gaseous hydrocarbons, stored in subterranean formations and to extract the fluids from the formations. Wellbores used to produce or extract fluids may be formed in earthen formations using earth-boring tools such as drill bits for drilling wellbores and reamers for enlarging the diameters of wellbores. An earth-boring tool may include one or more cutting elements secured to a blade of the tool. Typically, the tool includes one or more cutter pockets on an outer surface of the tool body, and the cutting elements are secured within the pockets by brazing.

SUMMARY

In some aspects, the techniques described herein relate to a cutting insert. The cutting insert incudes a base surface configured to be connected to a cutting element base. The cutting insert further includes a cutting surface, the cutting surface includes a vertical most point and a cutting edge. The cutting edge being closer to the base surface than the vertical most point.

In some aspects, the techniques described herein relate to a drilling bit. The bit includes a body with plurality of blades, a bore, and an insert cavity. Each blade of the plurality of blades further includes a plurality of blade cutting elements. The bore is hydraulically connected to the insert cavity. The bit further includes a bit insert. The bit insert is inserted into and fixed to the insert cavity. The bit further includes an insert cutting element connected to the bit insert in a cone region of the body.

In some aspects, the techniques described herein relate to a cutting assembly. The cutting assembly includes an insert that includes an ultrahard material. At least part of the insert has an ovoid outer surface. The cutting assembly further includes a matrix with a matrix material surrounding the insert by at least 50% in at least one axis to restrain insert in the matrix. A contact surface between the insert and the matrix includes the ovoid outer surface.

This summary is provided to introduce a selection of concepts that are further described in the detailed description. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in limiting the scope of the claimed subject matter. Additional features and aspects of embodiments of the disclosure will be set forth herein, and in part will be obvious from the description, or may be learned by the practice of such embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which the above-recited and other features of the disclosure can be obtained, a more particular description will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. For better understanding, the like elements have been designated by like reference numbers throughout the various accompanying figures. While some of the drawings may be schematic or exaggerated representations of concepts, at least some of the drawings may be drawn to scale. Understanding that the drawings depict some example embodiments, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 shows one example of a drilling system for drilling an earth formation to form a wellbore, according to at least one embodiment of the present disclosure;

FIGS. 2-1 and 2-2 are a perspective view of a bit, according to at least one embodiment of the present disclosure;

FIG. 2-2 is a representation of the bit of FIG. 2-1 having faceted cutting elements secured to faceted cutting element pockets;

FIG. 3-1 is a cross-sectional view of a cutting insert, according to at least one embodiment of the present disclosure;

FIG. 3-2 is a cross-sectional view of a cutting insert, according to at least one embodiment of the present disclosure;

FIG. 3-3 is a cross-sectional view of a cutting insert, according to at least one embodiment of the present disclosure;

FIG. 4 is a cross-sectional view of a cutting insert, according to at least one embodiment of the present disclosure;

FIG. 5 is a cross-sectional view of a cutting insert, according to at least one embodiment of the present disclosure.

FIGS. 6-1, 6-2, 6-3, 6-4, and 6-5 are a cross-sectional view of a different cutting inserts in relation to vertical axis of the cutting insert, according to at least one or more embodiments of the present disclosure.

DETAILED DESCRIPTION

This disclosure generally relates to devices, systems, and methods for a cutting insert for drilling. A cutting element can include a substrate with an ultrahard layer bonded to an upper surface of a base surface. The ultrahard layer is typically formed into a shape based on the function of the cutting element. For example, a scraping cutting element typically includes a flat cutting surface that is parallel or approximately parallel to the substrate and/or the base of the cutting element. In some examples, the ultrahard layer can have a conical, frustoconical, or domed surface. This may help to facilitate crushing of the rock and/or as depth-of-cut control to reduce blade wear. But these cutting elements do not efficiently engage the formation with a scraping motion. In accordance with at least one embodiment of the present disclosure, a cutting insert may include a vertical most point that is furthest away from the base surface and where the vertical most point is away from the conical axis of the cutting insert. The cutting insert may further include a cutting surface that is vertically closer to the base surface than the vertical most point of the cutting insert. The cutting surface is configured to scrape the earth formation. One possible advantage of this type of cutting surface configuration is to provide more efficient scraping, while also protecting the scraping cutting surface from bit axial impact with the vertical most point of the cutting insert (e.g., the tip) which could lead to pre-mature damaging or dulling.

In some embodiments, the cutting surface can include a bore that is in fluid communication with a fluid passage in the body of the bit. The drilling fluid may pass through the bore, exiting out of the cutting surface. One possible advantage of allowing drilling fluid to pass through the bore and exit out of the cutting surface is to clean the cutting surface to allow more efficient scraping and cooling of the cutting tip. In yet another embodiment, allowing drilling fluid to pass through the bore and exit out of the cutting surface is to clean the cutting surface to protect dulling or damaging the tip of the cutting insert.

Conventionally, an engaging element (e.g., a cutting or crushing element) includes only one engaging surface (e.g., a cutting or a crushing surface) on the engaging insert (e.g., cutting or a crushing element). In some embodiments, it may be beneficial to include a plurality of engaging surfaces in a single engaging insert. In accordance with at least one embodiment of the present disclosure, an engaging insert may include a vertical most point that is furthest away from a base surface. In some embodiments, the vertical most point is offset (e.g., laterally) from the longitudinal axis of the engaging insert. The engaging insert may include a cutting surface that is vertically closer to the base surface than the vertical most point (e.g., a crushing surface) of the engaging insert. The cutting surface being configured to scrape the earth formation. In some embodiments, the engaging insert may further include an additional engaging insert. For example, the engaging insert may include an insert pocket to receive the additional engaging insert creating two or more engaging surfaces in a single engaging element. The conical cutting element may be configured to crush an earth formation and the cutting surface may be configured to scrape (e.g., shear with a cutting face) the earth formation. One possible benefit of having two different purpose cutters in a single cutting insert is to provide more efficient drilling with dual purpose cutting insert by, for example, simultaneously shearing with the cutting face, crushing with the crushing element, and providing protection to the rest of the cutter and/or bit with the most vertical point.

In accordance with at least one embodiment of the present disclosure, a cutting insert may include multiple cutting faces oriented on both sides of the cylindrical axis of the cutting insert. In some embodiments, a cutting surface includes a vertical most point and a cutting edge. The cutting edge is closer to the cutting element base surface than the vertical most point, and the vertical most point is away from the cylindrical axis or at the cylindrical axis of the insert or it is in front of the cylindrical axis of the overall insert. The tip of the cutting edge is at the same vertical height as the vertical most point. The cutting insert may further include a bullet crusher. The vertical most point of the bullet crusher being away from the cylindrical axis. In one or more embodiments, the bullet crusher is configured to crush earth formation while the cutting edge of the cutting element is configured to scrape the earth formation. One possible benefit of having two different purpose cutters in a single cutting insert is to provide more efficient drilling with dual purpose cutting insert.

FIG. 1 shows one example of a drilling system 100 for drilling an earth formation 101 to form a wellbore 102. The drilling system 100 includes a drill rig 103 used to turn a drilling tool assembly 104 which extends downward into the wellbore 102. The drilling tool assembly 104 may include a drill string 105, a bottomhole assembly (“BHA”) 106, and a bit 110, attached to the downhole end of the drill string 105.

The drill string 105 may include several joints of drill pipe 108 connected end-to-end through tool joints 109. The drill string 105 transmits drilling fluid through a central bore and transmits rotational power from the drill rig 103 to the BHA 106. In some embodiments, the drill string 105 may further include additional components such as subs, pup joints, etc. The drill pipe 108 provides a hydraulic passage through which drilling fluid is pumped from the surface. The drilling fluid discharges through selected-size nozzles, jets, or other orifices in the bit 110 for the purposes of cooling the bit 110 and cutting structures thereon, and for lifting cuttings out of the wellbore 102 as it is being drilled.

The BHA 106 may include the bit 110 or other components. An example BHA 106 may include additional or other components (e.g., coupled between to the drill string 105 and the bit 110). Examples of additional BHA components include drill collars, stabilizers, measurement-while-drilling (“MWD”) tools, logging-while-drilling (“LWD”) tools, downhole motors, underreamers, section mills, hydraulic disconnects, jars, vibration or dampening tools, other components, or combinations of the foregoing. The BHA 106 may further include a rotary steerable system (RSS). The RSS may include directional drilling tools that change a direction of the bit 110, and thereby the trajectory of the wellbore. At least a portion of the RSS may maintain a geostationary position relative to an absolute reference frame, such as gravity, magnetic north, and/or true north. Using measurements obtained with the geostationary position, the RSS may locate the bit 110, change the course of the bit 110, and direct the directional drilling tools on a projected trajectory.

In general, the drilling system 100 may include other drilling components and accessories, such as special valves (e.g., kelly cocks, blowout preventers, and safety valves). Additional components included in the drilling system 100 may be considered a part of the drilling tool assembly 104, the drill string 105, or a part of the BHA 106 depending on their locations in the drilling system 100.

The bit 110 in the BHA 106 may be any type of bit suitable for degrading downhole materials. For instance, the bit 110 may be a drill bit suitable for drilling the earth formation 101. Example types of drill bits used for drilling earth formations are fixed cutter or drag bits. In other embodiments, the bit 110 may be a mill used for removing metal, composite, elastomer, other materials downhole, or combinations thereof. For instance, the bit 110 may be used with a whipstock to mill into casing 107 lining the wellbore 102. The bit 110 may also be a junk mill used to mill away tools, plugs, cement, other materials within the wellbore 102, or combinations thereof. Swarf or other cuttings formed by use of a mill may be lifted to surface or may be allowed to fall downhole.

In accordance with at least one embodiment of the present disclosure, the bit 110 may include a bore, an insert cavity, and plurality of blades with plurality of blade cutting elements, as further discussed down below.

In accordance with numerous embodiments, blades of a bit 110 may have numerous insert cavities that are configured to receive or engage with a cutter. In various embodiments, one or more cutting elements may be oriented so that one of the cutting surfaces faces a direction of rotation of the bit 110. In this manner, the cutting element may engage the formation as the bit 110 is rotated. In some embodiments, the cutting element may be an active cutting element configured to engage with the formation rather than a passive cutting element configured to provide depth of cut control or to reduce wear of the surrounding bit material. In some embodiments, the cutting element may be oriented so that an edge between two adjacent cutting surfaces may be oriented in the direction of rotation of the bit 110. In some embodiments, securing the cutting element to the insert cavity may increase the strength of the connection between the cutting element and the bit.

FIGS. 2-1 and 2-2 are a perspective view of the bit 210. The bit 210 may include a bit body 212 from which a plurality of blades 214 may protrude. At least one of the blades 214 may have a plurality of cutting elements connected thereto. In some embodiments, at least one of the cutting elements may be a planar cutting element, such as a shear cutting element. In other embodiments, at least one of the cutting elements may be a non-planar cutting element, such as a conical cutting element or a ridged cutting element.

The blade 214 includes a leading surface 216, an outer surface 218, and a trailing surface 220. The leading surface 216 may face forward in a rotational direction 222 of the bit 210. As the bit 210 rotates in the rotational direction 222, the leading surface 216 may encounter and/or pass by features of the formation before the outer surface 218 and/or a trailing surface 220. The outer surface 218 may face rearward in the rotational direction 222 of the bit 210. For example, as the bit 210 rotates in the rotational direction 222, the trailing surface 220 may pass by features of the formation after the leading surface 216 and/or the outer surface 218.

As illustrated in FIG. 2-1, many embodiments of a bit 210 may include a plurality of engagement elements 224 that are installed in the outer surface 218 of the blade 214. An engagement element 224 may be a cutting or crushing element that is configured to engage the formation with a cutting or crushing functionality. In some embodiments, the blade 214 may include an insert cavity configured to receive a cutting insert 226 according to the various embodiments described herein. The insert cavity may penetrate into the blade 214 along a pocket axis. For example, a cylindrical pocket may be formed into the outer surface 218 of the blade 214, in other words the outer surface 218 of the blade 214 may have one or more cylindrical pockets located therein. In some embodiments, an engagement element 224 is also inserted into an insert cavity. The cutting insert 226 and/or the engagement element 224 may have a cylindrical shape that is complementary to the cylindrical pocket of the insert cavity. The cutting insert 226 and/or the engagement element 224 may be secured to the blade 214 at the outer surface 218 in one of the insert cavities. The cutting insert 226 and/or engagement element 224 may be secured to the insert cavity in any manner. For example, the cutting insert 226 and/or engagement element 224 may be secured to the insert cavity by braze, weld, press fit, mechanical fastener, any other connection mechanism, and combinations thereof. In some embodiments, the cutting insert 226 may be secured to the blade 214 at any portion of the bit 210.

FIG. 3-1 is a cross-sectional view of a cutting insert 326-1, according to at least one embodiment of the present disclosure. The cutting insert 326-1 includes an engaging surface 334 or cutting portion. In some embodiments, the cutting insert 326-1 may further include a substrate 332. The substrate 332 can be configured to be connected to the cutting insert 326-1 via a cutting element base surface 342. The base surface 342 is shown as planar, but in some embodiments, may be non-planar. The cutting insert 326-1 may be formed from an ultrahard material. For example, the ultrahard material may be Polycrystalline diamond (PCD), sapphire, moissantite, hexagonal diamond (Lonsdaleite), tungsten carbide, cubic boron nitride (cBN), polycrystalline cBN (PcBN), Q-carbon, binderless PcBN, diamond-like carbon, boron suboxide, aluminum manganese boride, metal borides, boron carbon nitride, PCD (including, e.g., leached metal catalyst PCD, non-metal catalyst PCD, and binderless PCD or nanopolycrystalline diamond (NPD)), any other ultrahard material, and combinations thereof. The cutting insert 326-1 and the substrate 332 may be connected via a high temperature and high pressure sintering process. For example, the substrate 332 could be made of tungsten carbide material and when assembled with polycrystalline diamond powder (for the cutting insert 326-1), the substrate 332 and the cutting insert 326-1 may be integrally formed using the high pressure and temperature sintering process. During sintering the Co material inside tungsten carbide migrates into the diamond powder as a catalyst so the diamond powder will be connecting to form a solid diamond network structure.

The cutting insert 326-1, in accordance with numerous embodiments, can include a cutting surface 344. The cutting surface 344 may be opposite the base surface 342. The cutting surface 344 can be configured in any number of ways to improve the functionality of the cutting insert 326-1. For example, the cutting surface 344 can include a vertical most point 336 (e.g., a crushing point) having a height 340 and a cutting edge 330 (e.g., the edge of the cutting surface 344) including a vertical most point 390. The cutting edge 330 can have a vertical most point 390 that can have a height 392. In various embodiments, the vertical most point 390 of the cutting edge 330 can represent a cutting edge of the cutting insert 326-1. The difference between the height 340 and height 392 is illustrated with arrow 394. The vertical most point 390 of the cutting surface 344 is closer to the cutting element base surface 342 than the vertical most point 336 of the cutting insert 326-1. In other words, the vertical most point 336 of the cutting insert 326-1 is vertically furthest away from the cutting element base surface 342 and the substrate 332. Furthermore, the vertical most point 336 is offset a distance 396 (e.g., a horizontal distance) away from a longitudinal axis 338 (e.g., a cylindrical longitudinal axis for a cylindrical cutting element) of the cutting insert 326-1. In some embodiments, the height difference (shown by arrow 394) could be a positive or negative number so to decide whether the element is designed for more crushing (e.g., height 340 is larger than height 392) or more shearing (e.g., height 340 is less than height 392). This relationship between the heights (e.g., height 340 and height 392) may apply to the one or more of the following embodiments. In some embodiments, the distance 396 could be positive or negative. In some embodiments, the measurements (e.g., height 340, height 392, distance 396) may vary.

The cutting insert 326-1 may have a circular cross-sectional (top-down) shape (e.g., a cylindrical shape). The cutting insert 326-1 can have the longitudinal axis 338 in the middle of the shape (e.g., cylindrical (as shown), polygonal, other shape) of the cutting insert 326-1. In many embodiments of a cutting insert, the vertical most point 336 may be offset from the longitudinal axis 338.

FIG. 3-2 is a cross-sectional view of a cutting insert 326-2, according to at least one embodiment of the present disclosure. The cutting insert 326-2 can include a base element or substrate 332 and an engaging surface 334. In numerous embodiments, the substrate 332 is configured to be connected to an engaging surface 334 via a cutting element base surface 342. As shown in FIG. 3-2 the cutting insert 326-2 further includes a bore 354.

As discussed herein, drilling fluid may pass into the bore 354 through an inlet 346 in fluid communication with a fluid passage in the bit body 212. The drilling fluid may pass out of the base through the exit opening 348 of the engaging surface 334 exiting out of the cutting surface 344. In particular, the exit opening 348 is located in the concave portion (e.g., as shown in cross section) of the cutting surface 344. One possible advantage of including the exit opening 348 in the cutting surface 344 is that the fluid may be used to keep the cutting surface 344 clean. This may allow the cutting insert 326-2 to cut formation material more efficiently.

FIG. 3-3 is a cross-sectional view of a cutting insert 326-5, according to at least one embodiment of the present disclosure. The cutting insert 326-5, according to various embodiments, can include a substrate 332 and an engaging surface 334. The substrate 332 can be configured to be connected to an engaging surface 334 via a cutting element base surface 342. As shown in FIG. 3-3 the cutting insert 326-5 further includes a bore 354. In various embodiments, the bore 354 may be positioned at an angle with respect to a side wall 380 and/or the cutting element base surface 342.

As discussed herein, embodiments of a cutting element may be disposed within a blade of a cutting bit where drilling fluid may pass into the bore 354 through an inlet 346, where the inlet may be in fluid communication with a fluid passage in the bit body 212. The drilling fluid may pass out of the base through the exit opening 348 of the engaging surface 334 exiting out of the cutting surface 344. In particular, the exit opening 348 is located in the cutting surface 344 in an angle that provides more efficient cleaning of the cutting surface 344. In some embodiments, the exit opening 348 may be close to the vertical most point 390 of the cutting edge 330 and/or is oriented vertically or at an angle. In some embodiments, the exit opening 348 may be located close to a side wall 380 of the cutting insert 326-5 and/or is oriented vertically or at an angle. It can be appreciated, that numerous embodiments of the cutting element with a bore 354 may have the bore be positioned at any suitable angle with respect to the outer side wall 380 and cutting face 330 such that the bore effectively cleans and cools the cutting element 344.

One possible advantage of including the exit opening 348 in the cutting edge 330 is that the fluid may be used to keep the cutting edge 330 clean and/or aid in cooling at least a portion of the cutting insert 326-5 and/or the substrate 332. For example, the cutting fluid may aid in cooling and/or cleaning the cutting surface 344 and/or the cutting edge 330. This may allow the cutting insert 326-5 to cut formation material more efficiently and/or increase the use life of the cutting insert 326-5.

FIG. 4 is a cross-sectional view of a cutting insert 426-3, according to at least one embodiment of the present disclosure. The cutting insert 426-3 may include a substrate 442 and an engaging surface 434. The substrate 432 is configured to be connected to the cutting insert 426-3 via the substrate 442 of the cutting insert 426-3. The cutting insert 426-3 may be formed from an ultrahard material. For example, the ultrahard material may be PCD, sapphire, moissantite, Lonsdaleite, tungsten carbide, cBN, PcBN, Q-carbon, binderless PcBN, diamond-like carbon, boron suboxide, aluminum manganese boride, metal borides, boron carbon nitride, PCD (including, e.g., leached metal catalyst PCD, non-metal catalyst PCD, and binderless PCD or nanopolycrystalline diamond (NPD)), any other ultrahard material, and combinations thereof.

The cutting insert 426-3, in accordance with numerous embodiments, can include a cutting surface 444. The cutting surface 444 may be opposite the substrate 442. The cutting surface 444 can be configured in any number of ways to improve the functionality of the cutting insert 426-3. For example, the cutting surface 444 can include a vertical most point 436 (e.g., a crushing point) having a height 440 and a cutting edge 430 (e.g., the edge of the cutting surface 444) including a vertical most point 490. The cutting edge 430 can have a vertical most point 490 that can have a height 492. In various embodiments, the vertical most point 490 of the cutting edge 430 can represent a cutting edge of the cutting insert 426-1. The difference between the height 440 and height 492 is illustrated with arrow 494. The vertical most point 490 of the cutting surface 444 is closer to the cutting element substrate 442 than the vertical most point 436 of the cutting insert 426-1. In other words, the vertical most point 436 of the cutting insert 426-1 is vertically furthest away from the cutting element substrate 442 and the substrate 432. Furthermore, the vertical most point 436 is offset a distance 496 (e.g., a horizontal distance) away from a longitudinal axis 438 (e.g., a cylindrical longitudinal axis for a cylindrical cutting element) of the cutting insert 426-1. In some embodiments, the height difference (shown by arrow 494) could be a positive or negative number so to decide whether the element is designed for more crushing (e.g., height 440 is larger than height 492) or more shearing (e.g., height 440 is less than height 492). This relationship between the heights (e.g., height 440 and height 492) may apply to the one or more of the following embodiments. In some embodiments, the distance 496 could be positive or negative. In some embodiments, the measurements (e.g., height 440, height 492, distance 496) may vary.

The cutting insert 426-3 may have a circular cross-sectional (top-down) shape, e.g., a cylindrical shape. The cutting insert 426-3 further includes a longitudinal axis 438 in the middle of the shape (e.g., cylindrical (as shown), polygonal, other shape) of the cutting insert 426-3. In many embodiments of a cutting insert, the vertical most point 436 may be offset a distance 496 away from the longitudinal axis 438.

In accordance with some embodiments, the cutting insert 426-3 may further include an additional engaging element (e.g., secondary cutting element 450), disposed within the cutting insert. The secondary cutting element 450 can have any desired shape such as a conical tip or any non-planar tip. Some embodiments may incorporate a planar tip within the secondary cutting element. In some embodiments, the additional engaging element may include a cutting insert (e.g., conical cutting insert 452) connected to the additional engaging element (e.g., at a base surface). As shown, a substrate of the additional engaging element may extend through the cutting surface 444 of the cutting insert 426-3. In some embodiments, the cutting insert of the additional engagement element may extend through the cutting surface 444 of the cutting insert 426-3. The cutting insert 426-3 further includes an insert opening (shown as a through hole—may include a pocket or other opening). The opening is shown as parallel to the longitudinal axis 438. In other embodiments, the opening (and therefore the additional engagement element) may be oriented at an angle to the longitudinal axis 438. In some embodiments, a cylindrical pocket may be formed into the engaging surface 434 and the substrate 432, into which the secondary cutting element 450 is inserted into. The secondary cutting element 450 may be secured to the engaging surface 434 and/or the substrate 432 in the insert cavity. The secondary cutting element 450 may be secured to the insert cavity in any manner. For example, the secondary cutting element 450 may be secured to the insert cavity by braze, weld, press fit, mechanical fastener, any other connection mechanism, or combinations thereof.

The cutting insert 426-3 (e.g., the primary engaging element) and additional engaging element may be configured to crush and/or scrape an earth formation. One possible benefit of having two different purpose cutters in a single cutting insert is to provide more efficient drilling with dual purpose cutting insert.

In accordance with some embodiments, the secondary cutting element 450 having the cutting insert 452 includes a vertical most point of the conical cutting element 456. In some embodiments, the vertical most point 455 of the conical cutting element 456 is vertically as far away from the substrate 432 as the vertical most point 436 of the engaging surface 434, when the cutting insert 426-3 is oriented in 0-degree angle. In some embodiments, the vertical most point of the conical cutting element 456 is vertically further away from the substrate 432 than the vertical most point 436 of the engaging surface 434, when the cutting insert 426-3 is oriented in 0-degree angle. In some embodiments, the vertical most point of the conical cutting element 456 is vertically closer to the substrate 432 than the vertical most point 436 of the engaging surface 434, when the cutting insert 426-3 is oriented in 0-degree angle.

FIG. 5 is a cross-sectional view of a cutting insert 526-4, according to at least one embodiment of the present disclosure. The cutting insert 526-4 includes a substrate 532 and an engaging surface 534. The substrate 532 is configured to be connected to an engaging surface 534 via a cutting element substrate 542. The engaging surface 534 may be formed from an ultrahard material. For example, the ultrahard material may be Polycrystalline diamond (PCD), sapphire, moissantite, hexagonal diamond (Lonsdaleite), tungsten carbide, cubic boron nitride (cBN), polycrystalline cBN (PcBN), Q-carbon, binderless PcBN, diamond-like carbon, boron suboxide, aluminum manganese boride, metal borides, boron carbon nitride, PCD (including, e.g., leached metal catalyst PCD, non-metal catalyst PCD, and binderless PCD or nanopolycrystalline diamond (NPD)), any other ultrahard material, and combinations thereof.

The engaging surface 534 includes a cutting surface 544, the cutting surface 544 being opposite to the cutting element substrate 542. The cutting surface 544 includes a first vertical most point 536 and a cutting edge 530. The first vertical most point 536 having a height 540 from the cutting element substrate 542.

The cutting insert 526-4 may have a circular cross-sectional (top-down) shape, e.g., a cylindrical shape. The cutting insert 526-4 further includes a cylindrical axis 538 in the middle of the cylindrical shape of the cutting insert 526-4. The first vertical most point 536 is a distance 596 away from the cylindrical axis 538 (e.g., the vertical axis).

The cutting insert 526-4 further includes a bullet crusher 558. The bullet crusher 558 includes a vertical most point of the bullet crusher 552 at the cutting surface 544 of the cutting insert 526-4. The bullet crusher 558 has a height 599 from the cutting element substrate 542. The vertical most point of the bullet crusher 552 is a distance 598 away from the vertical axis 538. In some embodiments, the distance 596 and distance 598 are equal. In some embodiments, as shown in FIG. 5, the distance 598 is longer than the distance 596. In some embodiments the distance 598 is shorter than the distance 596.

In some embodiments, as shown in FIG. 5, the vertical most point of the bullet crusher 552 is vertically as far away from the substrate 532 as the first vertical most point 536 of the engaging surface 534, when the cutting insert 526-4 is oriented in 0-degree angle. In some embodiments, the vertical most point of the bullet crusher 552 is vertically further away from the substrate 532 than the first vertical most point 536 of the engaging surface 534, when the cutting insert 526-4 is oriented in 0-degree angle. In some embodiments, the vertical most point of the bullet crusher 552 is vertically closer to the substrate 532 than the first vertical most point 536 of the engaging surface 534, when the cutting insert 526-4 is oriented in 0-degree angle. In one or more embodiments, the bullet crusher 558 is configured to crush earth formation and the cutting edge 530 of the engaging surface 534 is configured to scrape the earth formation.

FIGS. 6-1, 6-2, 6-3, 6-4, 6-5 are a cross-sectional view of a different cutting inserts in relation to vertical axis of the cutting insert, according to at least one embodiment of the present disclosure. FIG. 6-1 represents a conventional conical cutting insert 670 in relation to the vertical axis 660 of the conventional cutting insert 670. The conventional cutting insert 670 includes a conical cutting element 672 that is oriented in forward raking position (e.g., positive angle) in relation to the vertical axis 660 of the conventional cutting insert 670. A forward raking position is an angle where the conical cutting element 672 is the first to engage with the earth formation 601 in relation to the movement of direction 664.

FIG. 6-2 represents a cutting insert 626-1 in accordance with at least one embodiment of the present disclosure. The cutting insert 626-1 may be the cutting insert 326-1 or 326-2 as discussed in connection with FIGS. 3-1 and 3-2. The cutting insert 626-1 is oriented in backward raking position (e.g., negative angle) in relation to the of the drill bit. A backward raking position is a negative angle 674-2 in relation to the vertical axis 660 of the cutting insert 626-1. The cutting insert 626-1 of FIG. 6-2 includes a cutting surface 644. When the cutting insert 626-1 is angled in backward raking position, the cutting insert is configured to scrape more of the earth formation 601 than if the cutting insert 626-1 is configured in a 0-degree angle in relation to the vertical axis 660. When the cutting insert 626-1 is configured in 0-degree angle in relation to the vertical axis 660, the cutting insert 626-1 may crush and scrape equal amount of earth formation.

FIG. 6-3 represents a cutting insert 626-2 in accordance with at least one embodiment of the present disclosure. The cutting insert 626-2 may be the cutting insert 226-2 as discussed in connection with FIG. 3-2. The cutting insert 626-2 is oriented in forward raking position (e.g., positive angle) in relation to the vertical axis 660. A forward raking position is a positive angle 674-1 in relation to the vertical axis 660 of the cutting insert 626-2. The cutting insert 626-2 of FIG. 6-3 includes a cutting surface 644. When the cutting insert 626-2 is angled in forward raking position, the cutting insert 626-2 is configured to crunch more of the earth formation 601 than if the cutting insert 626-1 is configured in a 0-degree angle in relation to the vertical axis 660. This is due because the vertical most point 636 is the first to engage with the earth formation 601. When the cutting insert 626-2 is configured in 0-degree angle in relation to the vertical axis 660, the cutting insert 626-1 may crush and scrape equal amount of earth formation.

FIG. 6-4 represents a cutting insert 626-3 in accordance with at least one embodiment of the present disclosure. The cutting insert 626-3 may be the cutting insert 426-3 as discussed in connection with FIG. 4. The cutting insert 626-3 is oriented in forward raking position (e.g., positive angle) in relation to the vertical axis 660. A forward raking position is a positive angle 674-1 in relation to the vertical axis 660 of the cutting insert 626-2. The cutting insert 626-3 of FIG. 6-4 includes a cutting surface 644. When the cutting insert 626-3 is angled in forward raking position, the cutting insert 626-3 is configured to crunch more of the earth formation 601 than if the cutting insert 626-3 is configured in a 0-degree angle in relation to the vertical axis 660. This is due because the vertical most point 636 is the first to engage with the earth formation 601. When the cutting insert 626-3 is configured in 0-degree angle in relation to the vertical axis 660, the cutting insert 626-1 may crush and scrape equal amount of earth formation.

FIG. 6-5 represents a cutting insert 626-4 in accordance with at least one embodiment of the present disclosure. The cutting insert 626-4 may be the cutting insert 526-4 as discussed in connection with FIG. 5. The cutting insert 626-4 is oriented in backward raking position (e.g., negative angle) in relation to the vertical axis 660. A backward raking position is a negative angle 674-2 in relation to the vertical axis 660 of the cutting insert 626-4. The cutting insert 626-4 of FIG. 6-5 includes a cutting surface 644. The cutting insert 626-4 further includes a bullet crusher 652. When the cutting insert 626-4 is angled in backward raking position, the bullet crusher 652 is configured to crunch more of the earth formation 601, and the cutting surface 644 is configured to cut more of the earth formation than if the cutting insert 626-4 is configured in a 0-degree angle in relation to the vertical axis 660.

One or more specific embodiments of the present disclosure are described herein. These described embodiments are examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, not all features of an actual embodiment may be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous embodiment-specific decisions will be made to achieve the developers'specific goals, such as compliance with system-related and business-related constraints, which may vary from one embodiment to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. For example, any element described in relation to an embodiment herein may be combinable with any element of any other embodiment described herein. Numbers, percentages, ratios, or other values stated herein are intended to include that value, and also other values that are “about” or “approximately” the stated value, as would be appreciated by one of ordinary skill in the art encompassed by embodiments of the present disclosure. A stated value should therefore be interpreted broadly enough to encompass values that are at least close enough to the stated value to perform a desired function or achieve a desired result. The stated values include at least the variation to be expected in a suitable manufacturing or production process, and may include values that are within 5%, within 1%, within 0.1%, or within 0.01% of a stated value.

A person having ordinary skill in the art should realize in view of the present disclosure that equivalent constructions do not depart from the spirit and scope of the present disclosure, and that various changes, substitutions, and alterations may be made to embodiments disclosed herein without departing from the spirit and scope of the present disclosure. Equivalent constructions, including functional “means-plus-function” clauses are intended to cover the structures described herein as performing the recited function, including both structural equivalents that operate in the same manner, and equivalent structures that provide the same function. It is the express intention of the applicant not to invoke means-plus-function or other functional claiming for any claim except for those in which the words ‘means for’ appear together with an associated function. Each addition, deletion, and modification to the embodiments that falls within the meaning and scope of the claims is to be embraced by the claims.

The terms “approximately,” “about,” and “substantially” as used herein represent an amount close to the stated amount that is within standard manufacturing or process tolerances, or which still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” and “substantially” may refer to an amount that is within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of a stated amount. Further, it should be understood that any directions or reference frames in the preceding description are merely relative directions or movements. For example, any references to “up” and “down” or “above” or “below” are merely descriptive of the relative position or movement of the related elements.

The present disclosure may be embodied in other specific forms without departing from its spirit or characteristics. The described embodiments are to be considered as illustrative and not restrictive. The scope of the disclosure is, therefore, indicated by the appended claims rather than by the foregoing description. Changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope.