Cutters with blade durability

Abstract

A cutting element has a cutting face having a geometry comprising at least one protrusion spaced a radial distance from a cutting element blade extending around an entire periphery of the cutting face to extend a lower portion within the distance between the at least one protrusion and the blade, wherein an axial height of the lower portion measured between the blade and a base of the at least one protrusion is less than 30% of a maximum axial height of the at least one protrusion measured between the base of the at least one protrusion and an axially highest point of the at least one protrusion.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit and priority of U.S. Patent Application No. 62 / 906,153, filed September 26, 2019, the entire contents of which are incorporated herein by reference. Background Technology

[0003] Cutting elements used in downhole drilling operations are typically made of layers of ultra-hard material to penetrate hard and abrasion-resistant soil formations. For example, cutting elements can be mounted to a drill bit (such as a rotary scraper bit) via brazing for drilling operations. Figure 1 An example of a fixed cutter bit 10 (sometimes called a scraper bit) is shown, which has multiple cutting elements 18 mounted thereon for drilling formations. The bit 10 includes a bit body 12 and multiple blades 16. The bit body 12 has an external threaded connection at one end 14, and the blades 16 extend from the other end of the bit body 12 and form the cutting surface of the bit 10. Multiple cutters 18 are attached to each blade 16 and extend from the blades to cut through the formation as the bit 10 rotates during drilling. The cutters 18 can deform the formation by scraping and shearing.

[0004] The superhard material layer of the cutting element can be formed under high temperature and high pressure conditions, typically in a pressing device designed to create such conditions, and bonded to a carbide matrix containing a metal binder or catalyst (such as cobalt). For example, polycrystalline diamond (PCD) is a superhard material used to manufacture cutting elements, where PCD cutters typically include diamond material formed on a support matrix (typically a sintered tungsten carbide (WC) matrix) and bonded to the matrix under high temperature and high pressure (HTHP) conditions.

[0005] PCD cutting elements are manufactured by placing a cemented carbide substrate in a container or box, and then loading a layer of diamond crystals or particles into the box adjacent to one side of the substrate. Many such boxes are typically placed in a reaction cell and then placed in an HPHT apparatus. The substrate and the adjacent diamond particle layer are then compressed under HPHT conditions, which promotes the sintering of the diamond particles to form a polycrystalline diamond structure. As a result, the diamond particles bond together, forming a diamond layer at the substrate interface. The diamond layer also bonds to the substrate interface.

[0006] Such cutting elements are frequently subjected to forces, torques, vibrations, high temperatures, and temperature variations during operation. As a result, stresses may begin to form within the structure. For example, scraper bits may exhibit increased stresses due to drilling anomalies during the drilling operation, such as bit rotation or bounce, which may cause the peeling, delamination, or cracking of the superhard material layer or matrix, thereby reducing or eliminating the effectiveness of the cutting element and reducing the overall bit wear life. Summary of the Invention

[0007] On one hand, embodiments of this disclosure relate to a cutting element having a cutting surface geometry including at least one protrusion spaced radially from a cutting edge extending around the entire periphery of the cutting surface, and a lower portion extending within the distance between the at least one protrusion and the cutting edge, wherein the axial height of the lower portion measured between the cutting edge and the base of the at least one protrusion is less than 30% of the maximum axial height of the at least one protrusion measured between the base of the at least one protrusion and the axial maxima of the at least one protrusion.

[0008] On the other hand, embodiments of this disclosure relate to a cutting element having a body, a diamond stage disposed at a cutting end of the body, and a cutting surface formed on the diamond stage at the cutting end, the cutting surface having a geometry including a planar portion and at least one protrusion protruding from the planar portion, wherein the planar portion completely surrounds the at least one protrusion.

[0009] On the other hand, embodiments of this disclosure relate to a cutting element having a cutting surface formed at its cutting end and a chamfer formed around the periphery of the cutting surface, wherein the cutting surface has at least one protrusion spaced radially from the inner diameter of the chamfer.

[0010] Other aspects and advantages of the invention will become apparent from the following description and the appended claims. Attached Figure Description

[0011] Figure 1 A perspective view of a conventional stationary cutter drill bit is shown.

[0012] Figure 2 A perspective view of a cutting element according to an embodiment of the present disclosure is shown.

[0013] Figure 3 It shows Figure 2 A side view of the cut element in the image.

[0014] Figure 4 A perspective view of a cutting element according to an embodiment of the present disclosure is shown.

[0015] Figure 5 It shows Figure 4 A side view of the cut element in the image.

[0016] Figure 6 A perspective view of a cutting element according to an embodiment of the present disclosure is shown.

[0017] Figure 7 It shows Figure 6 A side view of the cut element in the image.

[0018] Figure 8 A perspective view of a cutting element according to an embodiment of the present disclosure is shown.

[0019] Figure 9 A side view of a cutting element in Figure 8 is shown.

[0020] Figure 10 A perspective view of a cutting element according to embodiments of the present disclosure is shown.

[0021] Figure 11 A side view of a cutting element in Figure 10 is shown.

[0022] Figure 12 A perspective view of a cutting element according to embodiments of the present disclosure is shown.

[0023] Figure 13 A side view of a cutting element in Figure 12 is shown.

[0024] Figure 14 A side view of a cutting element according to embodiments of the present disclosure is shown.

[0025] Figure 15 and Figure 16 A finite element analysis comparing stress accumulation in a cutting element according to embodiments of the present disclosure Figure 15 ) to a comparative cutting element Figure 16 under the same conditions is shown.

[0026] Figure 17 and Figure 18 A finite element analysis comparing cutting action of a cutting element according to embodiments of the present disclosure Figure 17 ) to a comparative cutting element Figure 18 under the same conditions is shown. DETAILED DESCRIPTION

[0027] Embodiments of the present disclosure generally relate to cutting elements that can be mounted on a drill bit for drilling into earthen formations, or other cutting tools. The cutting elements disclosed herein can include a cutting face geometry designed to improve the durability of the cutting element while maintaining a high rock cutting efficiency. The cutting face geometry can include at least one protrusion or ridge spaced apart from a blade of the cutting face such that, during operation, the protrusion can exert a stress to fracture the formation, and the spacing apart from the blade can allow for less stress to accumulate at the blade, thereby increasing the durability of the blade.

[0028] In some embodiments, the cutting element can include a chamfer formed adjacent the edge of the cutting element and around the periphery of the cutting face, wherein the cutting face geometry includes at least one protrusion spaced a distance from the chamfer. The distance between the protrusion formed around the periphery of the cutting face and the chamfer can be greater than the radial distance of the chamfer, equal to the radial distance of the chamfer, or less than the radial distance of the chamfer.

[0029] Figure 2 and Figure 3 Perspective and side views of an example of a cutting element 100 according to embodiments of the present disclosure are shown. The cutting element 100 includes a body having a base 102 and a cutting end 104 at opposite axial ends, an outer side surface 108, and a longitudinal axis 106 extending axially through the center of the cutting element. The body can be formed of a diamond or other superhard material table disposed on a substrate, where the superhard material table forms the cutting end 104 and the substrate forms the base 102. In some embodiments, the entire body including the cutting end 104 and the base 102 can be formed of superhard material.

[0030] A cutting face 110 is formed at the cutting end 104 of the cutting element and is bounded around its periphery by a cutting edge 112, where the intersection between the outer side surface 108 and the cutting face 110 forms the edge 112. In the illustrated embodiment, a chamfer 114 is formed around the entire periphery of the cutting face 110, where the intersection of the chamfer 114 portion of the cutting face 110 and the outer side surface 108 forms the edge 112. The chamfer 114 is inclined radially inward from the edge 112 such that an outer diameter 115 of the chamfer 114 is at a first axial location at the edge 112 of the cutting element, and an inner diameter 117 of the chamfer 114 is radially inward of the edge 112 and at a second axial location relatively further from the base 102 of the cutting element than the first axial location. In some embodiments, the cutting face can have a chamfer formed partially around its periphery (less than the entire periphery of the cutting face), or can have no chamfer around the periphery of the cutting face.

[0031] The cutting face 110 has a geometry that includes a protrusion 120 spaced a radial distance 130 from the cutting edge 112 (where radial distance is measured in a direction from the cutting edge 112 toward the longitudinal axis 106), and a radial distance 131 from the inner diameter 117 of the chamfer 114. According to embodiments of the present disclosure, the radial distance 130 between one or more protrusions formed on the cutting face and the edge 112 of the cutting element can vary around the cutting edge 112, for example, when the protrusion 120 is offset from the axial center of the cutting face, when the protrusion 120 is axially symmetric about the longitudinal axis 106 of the cutting element, when there are multiple protrusions, and / or when the protrusion has a base shape that is different from the periphery of the cutting face 110. For example, as shown in FIG. 2, the radial distance 130 between the protrusion 120 and the edge 112 of the cutting element 100 varies around the cutting edge 112. Figure 2 and 3As shown in the embodiments of FIGS. 1-3, the center axis 126 of the protrusion 120 can be offset from the longitudinal axis 106 of the cutting element, where the radial distance 130 between the protrusion 120 and the cutting edge 112 varies around the cutting edge 112 of the cutting element. In other embodiments, the distance between the protrusion formed on the cutting face and the cutting edge of the cutting element can be uniform around the cutting edge.

[0032] When the protrusion 120 is axisymmetric, the radial distance 130 can range, for example, from 0%, at least 1%, at least 2%, at least 5%, or at least 10% of the cutting face diameter 115 to less than 20%, less than 30%, or less than 45% of the cutting face diameter 115, and when the protrusion 120 is axisymmetric, for example, it can range from 0%, at least 1%, at least 2%, at least 5%, or at least 10% of the cutting face diameter 115 to less than 60%, less than 70%, less than 80%, or less than 90% of the cutting face diameter 115. For example, in the embodiments shown in FIGS. 1-3, the radial distance 130 can be between 2% and 10% of the cutting face diameter 115 at the point 132 where the protrusion 120 is closest to the cutting edge, and the radial distance 130 can be between 20% and 40% of the cutting face diameter from the point 134 around the cutting edge 112 where the protrusion 120 is farthest from the cutting edge 112. Figure 2 and 3 In the embodiments shown in FIGS. 1-3, the distance 130 can be between 2% and 10% of the cutting face diameter 115 at the point 132 where the protrusion 120 is closest to the cutting edge, and the distance 130 can be between 20% and 40% of the cutting face diameter from the point 134 around the cutting edge 112 where the protrusion 120 is farthest from the cutting edge 112.

[0033] Furthermore, when the protrusion 120 is axisymmetric, the radial distance 131 between the protrusion 120 and the inner diameter of the chamfer 114 can range, for example, from 0%, at least 1%, at least 2%, at least 5%, or at least 10% of the cutting face diameter 115 to less than 20%, less than 30%, or less than 45% of the cutting face diameter 115, and when the protrusion 120 is axisymmetric, for example, it can range from 0%, at least 1%, at least 2%, at least 5%, or at least 10% of the cutting face diameter 115 to less than 60%, less than 70%, less than 80%, or less than 90% of the cutting face diameter 115.

[0034] The geometry of the cutting face according to embodiments of the present disclosure can generally be divided into two categories: a protrusion 160 and a lower portion 150, where the protrusion 160 can include one or more protrusions formed on the cutting face 110, and the lower portion 150 can include the portion of the cutting face 110 within the distance (e.g., radial distance 130) between the one or more protrusions 120 and the cutting edge or the outer periphery of the cutting face. In embodiments having a chamfer 114 formed around at least a portion of the cutting face periphery, the lower portion 150 of the cutting face 110 can include the chamfer 114.

[0035] The cutting element height 140 is measured axially between the base 102 of the cutting element 100 and the cutting face 110. The height 140 can vary by less than 10%, less than 5%, or less than 2% around the edge 112 and within the lower portion 150 of the cutting face. The protruding portion 160 of the cutting face includes a single protrusion 120 having an axial height 125 measured along the protrusion 120 between the protrusion base 122 and the cutting face surface 111. The lower portion 150 can have an axial height 155 measured between the lowest axial point 113 in the lower portion 150 (in the illustrated embodiment, it is around the edge 112 of the cutting element 100 where the cutting face 110 meets the outer lateral surface 108 of the cutting element 100) and the base 122 of the protrusion 120. According to embodiments of the present disclosure, the lower portion 150 can have an axial height 155 that is less than 30%, 20%, or 10% of the maximum axial height 125 of the protrusion 120, where the maximum axial height of the protrusion is measured between the base 122 of the protrusion 120 and the highest point (e.g., the apex 124) of the protrusion 120.

[0036] The lower portion 150 can be distinguished from the protruding portion 160, for example, by a difference in axial height within each region. In embodiments where the cutting element base 102 is a substantially flat surface extending along a plane that is perpendicular to the longitudinal axis 106 of the cutting element, the lower portion 150 can be distinguished from the protruding portion 160 by a difference in cutting element height within each region as measured from the base 102 of the cutting element to its cutting face 110. For example, the height 140 measured between the base 102 and the cutting face 110 of the cutting element in the lower portion 150 can vary by less than 10%, less than 5%, or less than 2%, while the height 125 in the protruding portion 160 can vary by at least 15%, at least 20%, or at least 25%. In some embodiments, the lower portion 150 can be distinguished as a region around the edge 112 of the cutting element 100 having a variation in axial height as measured from the lowest axial point 113 in the lower portion 150 to the highest axial point 122 in the lower portion 150 that is less than 10% of the maximum axial height of the protrusion(s) on the cutting face, where the maximum axial height of the protrusion(s) on the cutting face is measured axially between the protrusion base 122 and the highest axial point 124 of the protrusion(s).

[0037] In Figure 2 and Figure 3In the illustrated embodiment, the protrusions 120 comprise a dome shape. However, possible protrusion geometries can also include other three-dimensional shapes having a rounded top or apex. For example, in some embodiments, the protrusions can be pyramidal in shape, having a plurality of planar sides extending from a polygonal base shape to a rounded apex. In some embodiments, the protrusions can have a polygonal base shape, with a plurality of curved or non-planar sides extending from the base to a rounded apex. Other possible protrusion geometries can include three-dimensional shapes having an angled top or apex. For example, the protrusions can have a truncated pyramid shape, where the top of the truncated pyramid can be a substantially flat surface.

[0038] The lower portion 150 includes a chamfer 114 formed around the cutting element's edge 112, where the chamfer 114 can provide the only change in height within the lower portion 150. In such embodiments, the axial height 155 of the chamfer, and thus the axial height 155 of the lower portion, can be less than 10% or less than 5% of the maximum axial height 125 of the protrusions 120, for example.

[0039] The lower portion 150 also includes a planar surface 116 extending along a plane 152 that is perpendicular to the longitudinal axis 106 of the cutting element. The planar surface 116 extends circumferentially around the entire base 122 of the protrusions 120, and radially from the base 122 of the protrusions 120 to the chamfer 114. In other embodiments, the planar surface along the plane 152 that is perpendicular to the longitudinal axis 106 can extend less than the entire circumference of the protrusions 120. Furthermore, in embodiments where the cutting element does not have a chamfer formed around at least a portion of the cutting edge, the planar surface along the plane that is perpendicular to the longitudinal axis can extend completely from at least one protrusion to the cutting edge.

[0040] As described above, the lower portion 150 of the cutting face has a limited axial height, as measured from the lowest point 113 of the lower portion 150 to the highest point 122 of the lower portion 150 (which, in this embodiment, but not all embodiments, can be the base 122 of the protrusions 120). Accordingly, the cutting elements of the present disclosure can have a lower portion 150 defined around the cutting edge 112, as part of the cutting face 110, extending a radial distance 130 from the cutting edge 112 toward the longitudinal axis 106, having a limited axial height 155.

[0041] The lower portion 150 of the cutting face 110 can have one or more planar surfaces 116 and / or one or more curved surfaces, such as concave or convex surfaces, where the one or more surfaces, individually or collectively, have a limited axial height 155. For example, according to embodiments of the present disclosure, the cutting face geometry can include a lower portion 150 having at least one planar surface 116 extending along a plane 152 that is perpendicular to the longitudinal axis 106 of the cutting element. In some embodiments, the cutting face geometry can include a lower portion 150 having at least one planar surface 116 extending along a plane 152 that is perpendicular to the longitudinal axis 106 of the cutting element and at least one inclined surface (e.g. Figure 5 For example, one or more inclined surfaces in the lower portion of the cutting face can extend downward from a planar surface toward the cutting edge.

[0042] According to embodiments of the present disclosure, the lower portion 150 can have a planar portion that encircles at least a portion of the base 122 of the protrusion 120. The planar portion can be a surface 116 extending along a plane 152 that is perpendicular to the longitudinal axis 106 of the cutting element 100, or can be an inclined surface (shown by dashed line 154) having a small inclination from the plane 152 that is perpendicular to the longitudinal axis 106, such that the inclined surface 154 remains within a limited axial height 155.

[0043] Figures 4-9 An example of a cutting element having a cutting face with a lower portion geometry that includes at least one planar surface and at least one inclined surface, according to embodiments of the present disclosure, is shown.

[0044] Referring to Figure 4 and Figure 5 respectively, perspective and side views of a cutting element 300, according to embodiments of the present disclosure, are shown. The cutting element 300 includes a base 302 at opposite axial ends of the cutting element and a cutting face 310, and a longitudinal axis 306 extending axially through the cutting element 300, where a cutting element height 340 is measured axially from the base 302 to the cutting face 310. The cutting face 310 includes a protruding portion 360 formed by a single protrusion 320 and a lower portion 350 formed by a planar portion 316 and a plurality of inclined surfaces 314.

[0045] In the illustrated embodiment, the planar portion includes a planar surface 316 that extends in a radial direction around the protrusion 320 and along a plane 352 that is perpendicular to the longitudinal axis 306 of the cutting element. The inclined surfaces 314 extend in axial and radial directions away from the planar surface 316 toward a cutting edge 312 of the cutting element, at an inclination 317 relative to the longitudinal axis 306. The edge 312 is formed at the intersection between the inclined surfaces 314 and the outer lateral surface 308 of the cutting element 300. As illustrated, the lower portion 350 includes a number of inclined surfaces 314 corresponding to the number of sides of the protrusion base 322 (in this case, three); however, other embodiments can include more or fewer inclined surfaces. The inclined surfaces 314 intersect with the cutting edge 312 and the planar surface 316 at angular transitions. In other embodiments, the transitions between adjacent surfaces can be curved or chamfered. The planar surface 316 and the inclined surfaces 314 are positioned radially between the protrusion 320 and the edge 312 of the cutting element 300 such that the protrusion 320 is spaced apart from the edge 312 by a radial distance 330.

[0046] The axial height 355 of the lower portion 350 is measured axially between the lowest point 318 of the lower portion (which, in the illustrated embodiment, is at the thickest portion of the inclined surfaces 314) and the highest point of the lower portion (which, in the illustrated embodiment, is along the planar surface 316 at the same axial height as the base 322 of the protrusion 320). The axial height 325 of the protruding portion 360 is measured axially between the base 322 of the protrusion 320 and the cutting face surface 311. The maximum axial height 325 of the protruding portion 360 is measured axially between the base 322 of the protrusion 320 and the highest portion of the protrusion 320, which, in the illustrated embodiment, is at the protrusion apex 324. The axial height 355 of the lower portion 350 of the cutting face can be limited to, for example, less than 15% of the maximum axial height 325 of the protruding portion 360 of the cutting face 310.

[0047] Furthermore, Figure 4 and Figure 5 The illustrated protrusion 320 has a triangular pyramid shape with rounded edges 326 and a rounded apex 324. However, in other embodiments, the protrusion can have a different pyramid shape, including a square pyramid or other polygonal pyramid, a pyramid with angular edges between its sides, or a truncated pyramid with angular and / or rounded edges. In some embodiments, the protrusion can be a linearly extending ridge, a dome, or other regular or irregular three-dimensional shape.

[0048] In certain embodiments, the protruding portion can have more than one protrusion. For example, Figure 6 and 7A perspective view and a side view of a cutting element 400 having a plurality of protrusions 420 are shown, respectively, in accordance with an embodiment of the present disclosure, wherein each protrusion 420 is spaced apart from a cutting edge 412 of the cutting element by a radial distance 430 and from each other by a distance 427. In the illustrated embodiment, a cutting face 410 of the cutting element has a protruding portion 460 that includes three spaced apart protrusions 420. The protrusions 420 can be spaced apart such that the cutting face between the longitudinal axis 406 and the protrusions 420 is planar and perpendicular to the longitudinal axis 406. However, other embodiments can include more than three spaced apart protrusions, two spaced apart protrusions, or a single protrusion.

[0049] In certain embodiments, the protrusions 420 can have a ridge shape that extends a length along the cutting face. One or more ridges can be arranged on the cutting face to extend a length 428 in the radial dimension of the cutting face 410 along a portion of the diameter 401 of the cutting face. For example, the cutting face can include a single ridge-shaped protrusion that extends a portion of the diameter of the cutting face from a first linear end a distance from the cutting edge, through the longitudinal axis of the cutting element, to a second linear end a distance from the opposite cutting edge. In another example, as shown in FIG. 4B, the cutting face can include a plurality of ridge-shaped protrusions 420 that extend a portion of the diameter of the cutting face from a first linear end 421 a distance from the cutting edge 412, through the longitudinal axis 406 of the cutting element, to a second linear end 422 a distance from the opposite cutting edge 412. Figure 6 and 7 As shown, the ridge-shaped protrusions 420 can extend a portion of the diameter (length 428) of the cutting face 410 from a first linear end 421 located at a radial distance 430 from the cutting edge 412 to a second linear end 422 located near the longitudinal axis 406. The height of the ridge-shaped protrusions can vary. For example, the linear ends 421, 422 of the ridges 420 can be relatively lower than a central portion of the ridge, such that the central portion can be an apex 423 of the ridge 420. Further, the ridge-shaped protrusions can have angled, rounded, or flat top sides.

[0050] In the illustrated embodiment, each protrusion 420 is ridge-shaped, extending linearly in a radial direction from near the longitudinal axis 406 toward the cutting edge 412. The top side of each ridge-shaped protrusion 420 is rounded along its length and width. In the length direction (along the length 428), each protrusion 420 has a first linear end 421 positioned a radial distance 430 from the cutting edge 412, an apex 423, and a second linear end 423 positioned a distance 429 from the longitudinal axis 406, where the axial height 425 of the ridge 420 along the length 428 decreases from the apex 423 toward the linear ends 421, 422. In accordance with embodiments of the present disclosure, ridge-shaped protrusions can have different top side geometries, including, for example, flat top sides with substantially consistent ridge height, angled top sides, rounded top sides, or angled top sides.

[0051] In embodiments having at least one ridge-shaped protrusion, the ridge can extend linearly in a radial direction, can extend radially from a distance from the cutting edge and through the central longitudinal axis (e.g., a radial distance greater than the radius of the cutting face), or as shown in Figure 6 and 7 the ridge can extend radially from a radial distance 430 from the cutting edge 412 to a distance 429 from the central longitudinal axis 406 (i.e., a radial distance less than the radius of the cutting face).

[0052] In certain embodiments, the ridge-shaped protrusion can extend linearly in a non-radial direction. For example, a ridge-shaped protrusion (shown by dashed line 470) can extend linearly at an angle 475 from a radial direction 474, for example, from a first linear end 471 positioned a radial distance 430 from the cutting edge 412 to a second linear end 472 positioned a radial distance 430 from the cutting edge 412, where the ridge 470 does not extend through the longitudinal axis 406. In some embodiments having a ridge that extends linearly in a non-radial direction, the ridge can extend a portion of a chord of the cutting face.

[0053] Further, Figure 6 and Figure 7 the protrusions 420 are arranged axially symmetrically around the longitudinal axis 406 of the cutting element 400. With this configuration, the cutting element 400 can have three identical potential working portions of the cutting edge 412 (i.e., portions of the cutting edge that are expected to contact a work surface during operation), including the portion of the cutting edge 412 proximate (but not contacting) the linear ends 421 of the protrusion ridges 420. Advantageously, if one working portion of the cutting edge 412 is worn due to prior use, this type of configuration can allow, for example, the cutting element 400 to be rotated and reused within a cutting tool. According to embodiments of the present disclosure, the cutting face can have other configurations that use multiple protrusions spaced apart from the cutting edge, including, for example, multiple protrusions having different shapes, using more or fewer than three protrusions, and / or spacing the multiple protrusions axially symmetrically or axially asymmetrically around the longitudinal axis.

[0054] Still referring to Figure 6 and Figure 7, the cutting face geometry also has a lower portion 450 that axially separates the protrusion 460 from the cutting edge 412 of the cutting element 400, where the lower portion 450 includes a planar surface 416 extending along a plane 452 that is perpendicular to the longitudinal axis 406 of the cutting element, a plurality of inclined surfaces 414, and a chamfer 415 formed along the cutting edge 412. The inclined surfaces 414 extend from a rounded or curved transition 417 that is inclined from the planar surface 416 to the chamfer 415 formed around the cutting edge 412, such that the cutting element height 440 at the transition 417 from the planar surface 416 is greater than the cutting element height 440 at the transition to the chamfer 415. Further, the cutting element height 440 along the inclined surfaces 414 decreases around the cutting edge 412 from a region 424 along the cutting edge nearest the first linear end 421 of the protrusion 420 to a lowest region 426 along the cutting edge 412.

[0055] The change in height along the inclined surfaces 414 causes the region 424 around the cutting edge 412 nearest the protrusion 420 to have a smaller change in height than the region 426 around the cutting edge 412 farthest from the protrusion 420. For example, the axial height of the lower portion 450 of the cutting face within a radial distance 430 between the region 424 along the cutting edge 412 nearest the protrusion 420 and the protrusion 420 can be less than 50%, less than 20%, less than 10%, or less than 5% of the axial height 440 of the remaining lower portion 450 of the cutting face. In some embodiments, the region 424 around the cutting edge nearest the protrusion 420 can have an axial height 440 that is less than 10%, less than 5%, less than 2%, or less than 1% of the maximum axial height 425 of the protrusion.

[0056] Referring now to Figure 8 and Figure 9 , respectively, illustrate perspective and side views of another example of a cutting element 500 according to embodiments of the present disclosure. The cutting element 500 has a cutting face 510 formed at an axial end opposite a cutting element base, where the cutting face 510 includes a protrusion 560 and a lower portion 550. The protrusion 560 is formed by a single protrusion 520 having a geometry that includes three linear ridges 526 extending from a lower linear end 521 to an upper linear end that meet at an apex 524.

[0057] In some embodiments, the cutting face geometry can include a plurality of ridges 526 that join together at the apex 524. In some embodiments, the cutting face geometry can include a plurality of protrusions spaced apart from one another (e.g., as shown in Figure 6 and 7 Further, according to embodiments disclosed herein, the one or more protrusions 520 formed on the cutting face 510 can be axi-symmetric (e.g., as shown in Figure 8 and 9The protrusion 520 can extend symmetrically about the longitudinal axis 506 of the cutting element 500 (as shown) or asymmetrically about the longitudinal axis 506 of the cutting element.

[0058] The lower portion 550 of the cutting face 510 includes a planar surface 516 that extends along a plane 552 that is perpendicular to the longitudinal axis 506 of the cutting element 500. Further, the planar surface 516 surrounds the entire base 522 of the protrusion 520, where the base 522 of the protrusion 520 transitions to the planar surface 516 at a curved transition 523. The planar surface 516 further forms a space between the protrusion 520 and a chamfer 518 formed around the periphery of the planar surface 516. Three inclined surfaces 514 extend in axial and radial directions away from a central region of the cutting face 510, including the planar surface 516 and the chamfer 518 around the planar surface 516, toward the cutting edge 512. The inclined surfaces 514 are bounded by and completely surround two chamfers: a chamfer 515 formed inside and around the cutting edge 512 and a chamfer 518 formed around the periphery of the planar surface 516.

[0059] The two chamfers 515 and 518 can intersect each other along an axially highest region 524 of the edge 512, forming a double-chamfered cutting tip 527. The axially highest region 524 of the edge of the cutting element 500 and / or the double-chamfered cutting tip 527 can be radially aligned with the linear ridge 526 of the protrusion 520 (i.e., along a shared radial plane, an example of which is shown by dashed line 528). A double-chamfered cutting tip formed by two intersecting chamfers proximate to the edge of a cutting element can also be formed in other embodiments of the present invention. For example, by modifying the cutting element design to have a second chamfer formed around the planar surface 416 and intersecting the chamfer 415, a double-chamfered cutting tip can be formed on the embodiment shown in FIG. 4A. Figure 6 and 7 A double-chamfered cutting tip can be formed on the embodiment shown in FIG. 5A by modifying the cutting element design to have a first chamfer formed around and proximate to the edge 312 of the cutting element and a second chamfer formed around the planar surface 316. Figure 4 and 5 A double-chamfered cutting tip can be formed on the embodiment shown in FIG. 5A by modifying the cutting element design to have a first chamfer formed around and proximate to the edge 312 of the cutting element and a second chamfer formed around the planar surface 316.

[0060] The inclined surfaces 514 and the chamfers 515, 518 can each have a slope that can keep the surface of the lower portion 550 of the cutting face 510 within a limited axial height 555, for example, that can be less than 50%, less than 20%, less than 10%, or less than 5% of the maximum axial height 525 of the protrusion 520. The slope of the chamfers relative to the longitudinal axis 506 of the cutting element can be greater than the slope of the inclined surfaces 514, and the slope of the chamfers relative to the longitudinal axis 506 can be greater than the protrusion slope of the protrusion 520 from the axially highest point of the protrusion to the base of the protrusion.

[0061] The protrusion 520 can be spaced apart from the nearest chamfer (chamfer 518) and the edge 512 of the cutting element. As shown, the protrusion 520 is spaced apart from the edge 512 of the cutting element by a radial distance 530, and is spaced apart from the inner diameter 517 of the chamfer 518 by a smaller radial distance.

[0062] Figure 10 and Figure 11 A perspective view and a side view, respectively, of another example of a cutting element 600 according to embodiments of the present disclosure are shown. The cutting element 600 includes a cutting face 610 and a base at opposite axial ends of the cutting element 600, an outer lateral surface 608, and an edge 612 formed where the cutting face 610 and the lateral surface 608 intersect. The geometry of the cutting face 610 includes three spaced apart protrusions 620 positioned at a radial distance 630 from the edge 612 of the cutting element 600, a planar surface 616 that completely surrounds the protrusions 620, and a chamfer 615 formed adjacent to and extending around the edge 612.

[0063] Each protrusion 620 is a ridge that extends linearly in a radial direction 674 from a first linear end 621 spaced apart from the edge 612 of the cutting element 600 by the radial distance 630 to a second linear end 622 proximate to the longitudinal axis 606 of the cutting element 600. The second linear ends 622 of the protrusions 620 are spaced apart from the longitudinal axis 606 and from each other by a distance 627. The planar surface 616 extends along a plane 652 that is perpendicular to the longitudinal axis 606 and completely encloses each protrusion 620. The chamfer 615 slopes between the planar surface 616 and the edge 612 of the cutting element 600, extends in an axial dimension from the planar surface 616 in a direction toward the base 602 of the cutting element 600, and extends in a radial dimension from the planar surface 616 in a direction radially outward.

[0064] Figure 12 and Figure 13 A perspective view and a side view, respectively, of another example of a cutting element 700 according to embodiments of the present disclosure are shown. The cutting element 700 has a cutting face 710 and a base 702 at opposite axial ends of the cutting element 700, a longitudinal axis 706 extending axially through the cutting element 700, an outer lateral surface 708, and an edge 712 formed where the outer lateral surface 708 and the cutting face 710 intersect.

[0065] The geometry of the cutting face 710 includes a protrusion 720 that is interior to and spaced a radial distance 730 from the cutting element blade 712. The geometry of the cutting face 710 also includes a planar surface 716 that completely encloses the protrusion 720, where the planar surface 716 extends from the boundary of the protrusion 720 to the chamfer 715 along a plane 752 that is perpendicular to the longitudinal axis 706. The chamfer 715 is formed between the planar surface 716 and the blade 712 of the cutting element 700 and extends around the entire blade 712 of the cutting element. Further, the chamfer 715 has a slope 707 with respect to the longitudinal axis 706 that extends axially from the planar surface 716 in a direction toward the base 702 of the cutting element and extends radially outward from the planar surface 716.

[0066] The protrusion 720 has a prismatic geometry with three linear ridges 726 that extend from a first linear end 721 in a radial direction 774 and join together at an apex 724 at the longitudinal axis 706, where an axial height 725 of the protrusion 720 gradually increases from the first linear end 721 to the apex 724. As shown, the first linear end 721 can be equally spaced in a circumferential direction, or can be unequally spaced in a circumferential direction (e.g., in the circumferential spacing between the tips of the “Y”). Further, the first linear end 721 are each spaced a radial distance 730 from the blade 712 of the cutting element 700. As shown, the first linear end 721 can be proximate to, but spaced apart from, the chamfer 715, or the ends of the protrusion can be in contact with the chamfer. Figure 12 Figure 12 13 As shown in the embodiments of FIGS. 1-3, the cutting face 110, 210, 310 can include a planar portion 120, 220, 320 that completely encloses at least one protrusion 130, 230, 330 that protrudes from the planar portion. The protrusion 130, 230, 330 can have a prismatic geometry with three linear ridges 132, 232, 332 that extend from a first linear end 131, 231, 331 in a radial direction 134, 234, 334 and join together at an apex 134, 234, 334 at the longitudinal axis 106, 206, 306, where an axial height 135, 235, 335 of the protrusion 130, 230, 330 gradually increases from the first linear end 131, 231, 331 to the apex 134, 234, 334. As shown, the first linear end 131, 231, 331 can be equally spaced in a circumferential direction, or can be unequally spaced in a circumferential direction (e.g., in the circumferential spacing between the tips of the “Y”). Further, the first linear end 131, 231, 331 are each spaced a radial distance 136, 236, 336 from the blade 112, 212, 312 of the cutting element 100, 200, 300. As shown, the first linear end 131, 231, 331 can be proximate to, but spaced apart from, the chamfer 115, 215, 315, or the ends of the protrusion can be in contact with the chamfer.

[0067] According to embodiments of the present disclosure, a cutting element can include a diamond table disposed at a cutting end of a body thereof, where a cutting face is formed on the diamond table at the cutting end. The cutting face geometry on the diamond table can include any of the cutting face geometries described herein, including, for example, a planar portion that completely encloses at least one protrusion that protrudes from the planar portion.

[0068] Figures 4-13 Embodiments in FIGS. 4-6 show examples of cutting elements with diamond tables, where a cutting face is formed on the diamond table, and a base body forms a base. For example, as shown in FIG. 4, a diamond table 570 is disposed on an interface 590 of a base body 580, where a cutting face 510 is formed at a cutting end of the diamond table 570, and a base is formed at an opposite axial end of the base body 580. In FIG. 5, a diamond table 670 is disposed on an interface 690 of a base body 680, where a cutting face 610 is formed at a cutting end of the diamond table 670, and a base is formed at an opposite axial end of the base body 680. In FIG. 6, a diamond table 770 is disposed on an interface 790 of a base body 780, where a cutting face 710 is formed at a cutting end of the diamond table 770, and a base is formed at an opposite axial end of the base body 780. Figure 8 Figure 13

[0069] ​​​​The diamond table can be disposed on the substrate, for example, by forming the diamond table on the substrate, infiltration, brazing, or other attachment means. For example, a diamond table can be formed on a substrate by placing diamond powder on a pre-formed substrate or substrate material and subjecting the diamond powder to high pressure high temperature conditions sufficient to cause diamond-diamond bonding, resulting in a polycrystalline diamond table attached to the substrate. In another example, the diamond table can be brazed to the substrate. Other methods of attaching a diamond table to a substrate can be used to form a cutting element in accordance with the embodiments disclosed herein.

[0070] The diamond table can be formed of thermally stable polycrystalline diamond, polycrystalline diamond, diamond composites, and combinations thereof. In addition, cutting elements of the present disclosure can utilize different types of superhard material to form the cutting end of the cutting element, instead of or in addition to diamond. For example, diamond-metal cermet composites, cubic boron nitride or other superhard material composites can be used to form the cutting end of the cutting element in accordance with the embodiments of the present disclosure.

[0071] The substrate material can include, for example, a metal carbide and a sintered metal binder. Suitably, the metal of the metal carbide can be selected from chromium, molybdenum, niobium, tantalum, titanium, tungsten, and vanadium, and alloys and mixtures thereof. For example, sintered tungsten carbide can be formed by sintering a stoichiometric mixture of tungsten carbide and a metal binder.

[0072] The geometry of the cutting face can be formed, for example, by pressing superhard material (e.g., diamond powder) into a negative shape having the geometry of the cutting face and subjecting the material to high pressure high temperature and / or infiltration of the superhard material (where conditions can depend on the superhard material) to form a superhard table having a cutting face with the geometry described herein. In some embodiments, the geometry of the cutting face can be formed by cutting material away from the superhard body (e.g., by laser cutting) to form at least one protrusion spaced a distance from the blade of the body of superhard material.

[0073] In some embodiments, after forming the cutting face geometry on the body of superhard material, the body of superhard material can be treated to change the composition of at least a portion of the cutting face. For example, a polycrystalline diamond table having a cutting face geometry in accordance with the embodiments of the present disclosure can be leached along at least a portion of the cutting face to form a thermally stable polycrystalline diamond portion of the cutting face.

[0074] According to embodiments of the present disclosure, the distance between the one or more protrusions on the cutting face and the cutting edge can correspond to the potential cutting depth of the cutting element when cutting. For example, a tool designer can anticipate the position of the cutting element on the cutting tool, including, for example, the back rake angle of the cutting element, the side rake angle of the cutting element, and the exposed height of the cutting element from the tool surface, to name a few examples. Based on the position of the cutting element on the cutting tool and other anticipated operating factors, such as the type of formation being drilled, weight on bit, tool rotational speed, and / or other factors, the tool designer can further anticipate the cutting depth of the cutting element (the depth the cutting element penetrates the formation). According to the design assumptions made in determining the potential cutting depth of the cutting element, the tool designer can design the cutting face geometry to include at least one protrusion that is spaced apart from the working portion of the cutting edge by a lower portion, such that during operation, only the lower portion of the cutting face can contact the working surface (e.g., the earthen formation) at an initial cutting depth, and a portion of the lower portion and the protrusion can contact the working surface at a cutting depth deeper than the initial cutting depth.

[0075] For example, Figure 14 A side view of a cutting element 200 cutting a formation 270 at a cutting depth D is shown, according to embodiments of the present disclosure. The cutting element 200 has a cutting face geometry that includes a protrusion 220 protruding from a lower portion 210 and spaced apart from a land 212 of the cutting face, where the lower portion 210 extends a radial distance R between the land 212 and the protrusion 220. Figure 14 The illustrated cutting element 200 includes a lower portion 210 that extends completely around the protrusion 220 and extends a uniform radial distance R from the land 212. However, as described above, the lower portion can extend different radial distances around the cutting land.

[0076] Along at least a portion of the cutting land 212 designed to contact the working surface, the radial distance R of the lower portion 210 can be small enough such that a portion of the protrusion 220 contacts the working surface at a particular cutting depth D. For example, when the cutting element 200 contacts the working surface of the formation 270 at a contact angle Q and a cutting depth D, the lower portion 210 around the portion of the land 212 contacting the formation can extend a radial distance R that is less than the cutting depth divided by sin(contact angle), as shown in the following equation: R < D / sin(Q).

[0077] By spacing a protruding portion of the cutting face apart from the cutting land by a radial distance, the maximum stress on the cutting face can be reduced. For example, Figure 15 and 16 Finite element analyses are shown comparing the stress accumulated on the cutting face of two different cutting elements impacting a rock formation at the same speed and at the same cutting depth. Figure 15 The cutting element 500 simulated in the middle has a cutting face geometry according to embodiments of the present disclosure, and also as illustrated in FIG. 5, the cutting element 500 has a lower portion 510 that extends a radial distance R between the land 512 and the protrusion 520. The cutting element 500 in the middle has a lower portion 510 that extends a radial distance R that is less than the cutting depth divided by sin(contact angle), as shown in the following equation: R < D / sin(Q).Figure 8 As shown, the protrusion 520 (which has the shape of three intersecting ridges 526 joined together at the apex 524) is spaced apart from the cutting edge 512. Figure 16 The simulated cutting element 800 has a cutting surface geometry including a protrusion 820 extending to the cutting edge 812. As shown, with... Figure 16 Compared to the cutting element 800 (where stress accumulation is indicated by brackets 801), Figure 15 The stress accumulated near and around the cutting edge 512 on the cutting element 500 is less (where stress accumulation is indicated by bracket 501).

[0078] As described herein, another advantage of the cutting surface geometry, which has a space between the cutting edge and at least one protrusion, includes improved cutting efficiency. For example, Figure 17 and 18 A cutting element 900 and a cutting blade extending to the cutting edge are shown respectively, comparing embodiments of the present disclosure. Figure 16 The protrusion shown in Figure 812) Figure 16 The cutting element 800 (as shown in Figure 820) Figure 16 The simulation of the cutting action (as shown in the image). Figure 17 As shown, according to embodiments of this disclosure, when the protrusion 920 is spaced apart from the cutting edge, it can act as a splitter to split or cleave the strata 990 being cut, which can improve cutting efficiency. Conversely, as Figure 18 As shown, it has a protrusion extending to the cutting edge. Figure 16 The cutting element 800 (shown as 820) can guide the chip 890 forward, which may cause the chip 890 to accumulate on the cutting surface, thereby reducing the cutting efficiency.

[0079] Industrial applicability

[0080] This disclosure generally relates to apparatus, systems, and methods for cutting elements that can be mounted on drill bits or other cutting tools for drilling into soil formations. Cutting tools, such as drill bits, may include one or more cutting elements. According to embodiments of this disclosure, the cutting tool may include a cutting element having a cutting face geometry designed to improve the durability of the cutting element and maintain high rock-cutting efficiency. The cutting face geometry may include at least one protrusion or ridge spaced apart from the cutting edge of the cutting face, such that during operation, the protrusion can apply stress to fracture the formation, and the spaced-apart nature allows less stress to accumulate at the cutting edge, thereby increasing the durability of the cutting edge.

[0081] In some embodiments, a cutting element can include a body having a base and a cutting end at opposite axial ends, and a cutting face formed at the cutting end. The cutting face includes at least one protrusion spaced a radial distance from a blade of the cutting element. The blade extends around an entire periphery of the cutting face. The cutting face includes a lower portion extending within the radial distance between the at least one protrusion and the blade. An axial height of the lower portion measured between the blade and the base of the at least one protrusion is less than 30% of a maximum axial height of the at least one protrusion measured between the base of the at least one protrusion and an axially highest point of the at least one protrusion. In some embodiments, the cutting element can include a chamfer formed inside and extending around the blade of the cutting element, where an axial height of the chamfer is within the axial height of the lower portion. In some embodiments, the lower portion can include at least one planar surface extending along a plane perpendicular to a longitudinal axis of the cutting element. The lower portion can include at least one inclined surface extending axially and radially outward from the at least one planar surface toward the blade. In some embodiments, the cutting element can include a diamond table disposed on a substrate. The cutting face can be formed on the diamond table, and the substrate forms the base. In some embodiments, the at least one protrusion includes at least one ridge extending a length along the cutting face. In some embodiments, the at least one protrusion includes a pyramid having a plurality of sides extending from a polygonal base shape to an apex. In some embodiments, the at least one protrusion includes a rounded top. In some embodiments, the at least one protrusion includes a plurality of ridges joined together at an apex, where the apex is an axially highest point of the at least one protrusion. In some embodiments, the radial distance is at least 5% of a diameter of the cutting face at a point of the at least one protrusion closest to the blade. In some embodiments, the at least one protrusion is axially symmetric about the longitudinal axis. In some embodiments, the at least one protrusion includes three or more protrusions. In some embodiments, the cutting face includes a planar surface at the longitudinal axis of the cutting element. In some embodiments, the axially highest point of the at least one protrusion is at the longitudinal axis of the cutting element. In some embodiments, the cutting element includes a chamfer formed inside and extending around the blade of the cutting element, where a chamfer slope of the chamfer relative to the longitudinal axis of the cutting element is greater than a protrusion slope.

[0082] In some embodiments, a cutting element includes a body, a diamond table disposed at a cutting end of the body, and a cutting face formed on the diamond table at the cutting end. The cutting face includes a geometry having a planar portion and at least one protrusion projecting from the planar portion. The planar portion completely surrounds the at least one protrusion. In some embodiments, the planar portion extends along a plane that is perpendicular to a longitudinal axis of the cutting element. In some embodiments, the cutting element includes at least one ramped surface extending from the planar portion to a lip of the cutting face at an inclination relative to the longitudinal axis of the cutting element. In some embodiments, the at least one protrusion includes a pyramid having a plurality of sides extending from a polygonal base shape to an apex. In some embodiments, the at least one protrusion includes a rounded top. In some embodiments, the planar portion extends from the at least one protrusion to the lip of the cutting face. In some embodiments, the cutting element includes a chamfer formed inside the cutting face and extending around the lip of the cutting face, wherein the planar portion is between the chamfer and the at least one protrusion. In some embodiments, the at least one protrusion is spaced a distance from the lip of the cutting face, wherein the distance is greater than 5% of a diameter of the cutting face.

[0083] In some embodiments, a cutting element includes a body having a base and a cutting end at opposite axial ends, a cutting face formed at the cutting end, and a chamfer formed at a periphery of the cutting face. The cutting face includes at least one protrusion spaced a radial distance from an inner diameter of the chamfer. In some embodiments, the radial distance is greater than a radial distance of the chamfer. In some embodiments, the at least one protrusion is axially symmetric about a longitudinal axis of the cutting element.

[0084] While the application has been described with respect to a limited number of embodiments, those skilled in the art, having the benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the application as described herein. Accordingly, the scope of the disclosure should only be limited by the claims appended hereto.

Claims

1. A cutting element comprising: a body having a base at opposite axial ends and a cutting end, wherein a substrate forms the base and a table of diamond disposed on the substrate forms the cutting end; a cutting face formed on the table of diamond, the cutting face comprising: at least one protrusion spaced a radial distance from a cutting edge of the cutting element such that a central axis of the at least one protrusion is offset from an axial center of the cutting face, and wherein the radial distance varies around the cutting edge, wherein the radial distance at a point of the protrusion closest to the cutting edge is between 2% and 10% of a diameter of the cutting face and the radial distance at a point of the protrusion furthest from the cutting edge around the cutting edge is between 20% and 40% of the diameter of the cutting face, the edge extending around an entire periphery of the cutting face, wherein the at least one protrusion comprises at least one ridge extending a length along the cutting face; and a lower portion extending within the radial distance between the at least one protrusion and the edge; wherein an axial height of the lower portion measured between the edge and a base of the at least one protrusion is less than 20% of a maximum axial height of the at least one protrusion measured between the base of the at least one protrusion and an axially highest point of the at least one protrusion, wherein the lower portion of the cutting face comprises a planar surface extending along a plane perpendicular to a longitudinal axis of the cutting element, the planar surface surrounding a base of the protrusion, a first chamfer formed inside and around the edge and a second chamfer formed around a periphery of the planar surface, the first chamfer and the second chamfer intersecting each other in an axial direction along the edge to form a double chamfered cutting tip, wherein a transition from the planar surface to an inclined surface forming the second chamfer is provided with a rounded or curved transition inclined from the planar surface, a height variation along the inclined surface forming the second chamfer is such that a region closest to the cutting edge of the at least one protrusion has a smaller height variation than a region furthest from the cutting edge of the at least one protrusion.

2. The cutting element of claim 1, wherein an axial height of the first chamfer is within the lower axial height.

3. The cutting element as defined in claim 1, wherein, The lower portion comprises at least one planar surface extending along a plane perpendicular to a longitudinal axis of the cutting element.

4. The cutting element according to claim 3, wherein, The lower portion further comprises at least one inclined surface extending axially and radially outwardly from the at least one planar surface towards the edge.

5. The cutting element according to claim 1, wherein, The at least one protrusion comprises a plurality of ridges joined together at an apex, and wherein the apex is an axially highest point of the at least one protrusion.

6. The cutting element according to claim 1, wherein, The at least one protrusion comprises a pyramid having a plurality of sides extending from a polygonal base shape to an apex.

7. The cutting element according to claim 1, wherein, The at least one protrusion comprises a rounded top.

8. The cutting element according to claim 1, wherein, The radial distance is at least 5% of a diameter of the cutting face at a point of the at least one protrusion closest to the edge.

9. The cutting element according to claim 1, wherein, The at least one protrusion comprises three or more protrusions.

10. The cutting element according to claim 1, wherein, The cutting face comprises a planar surface at a longitudinal axis of the cutting element.

11. The cutting element according to claim 1, wherein, The axially highest point of the at least one protrusion is at a longitudinal axis of the cutting element.

12. The cutting element of claim 1, wherein a chamfer slope of the first chamfer relative to a longitudinal axis of the cutting element is greater than a protrusion slope between the base and the axially highest point of the at least one protrusion.

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