Patent Grant
10267096
Embodiments disclosed herein relate generally to cutting elements for drill bits or other cutting tools incorporating the same. More particularly, embodiments disclosed herein relate generally to rotatable cutting elements.
Drill bits used to drill wellbores through earth formations generally are made within one of two broad categories of bit structures. Depending on the application/formation to be drilled, the appropriate type of drill bit may be selected based on the cutting action type for the bit and its appropriateness for use in the particular formation. Drill bits in the first category are generally known as “roller cone” bits, which include a bit body having one or more roller cones rotatably mounted to the bit body. The bit body is typically formed from steel or another high strength material. The roller cones are also typically formed from steel or other high strength material and include a plurality of cutting elements disposed at selected positions about the cones. The cutting elements may be formed from the same base material as is the cone. These bits are typically referred to as “milled tooth” bits. Other roller cone bits include “insert” cutting elements that are press (interference) fit into holes formed and/or machined into the roller cones. The inserts may be formed from, for example, tungsten carbide, natural or synthetic diamond, boron nitride, or any one or combination of hard or superhard materials.
Drill bits of the second category are typically referred to as “fixed cutter” or “drag” bits. Drag bits, include bits that have cutting elements attached to the bit body, which may be a steel bit body or a matrix bit body formed from a matrix material such as tungsten carbide surrounded by a binder material. Drag bits may generally be defined as bits that have no moving parts. However, there are different types and methods of forming drag bits that are known in the art. For example, drag bits having abrasive material, such as diamond, impregnated into the surface of the material that forms the bit body are commonly referred to as “impreg” bits. Drag bits having cutting elements made of an ultrahard cutting surface layer or “table” (typically made of polycrystalline diamond material or polycrystalline boron nitride material) deposited onto or otherwise bonded to a substrate are known in the art as polycrystalline diamond compact (“PDC”) bits.
PDC cutters have been used in industrial applications including rock drilling and metal machining for many years. In PDC bits, PDC cutters are received within cutter pockets, which are formed within blades extending from a bit body, and are typically bonded to the blades by brazing to the inner surfaces of the cutter pockets. The PDC cutters are positioned along the leading edges of the bit body blades so that as the bit body is rotated, the PDC cutters engage and drill the earth formation. In use, high forces may be exerted on the PDC cutters, particularly in the forward-to-rear direction. Additionally, the bit and the PDC cutters may be subjected to substantial abrasive forces. In some instances, impact, vibration, and erosive forces have caused drill bit failure due to loss of one or more cutters, or due to breakage of the blades.
In a typical PDC cutter, a compact of polycrystalline diamond (“PCD”) (or other superhard material, such as polycrystalline cubic boron nitride) is bonded to a substrate material, which is typically a sintered metal-carbide to form a cutting structure. PCD comprises a polycrystalline mass of diamond grains or crystals that are bonded together to form an integral, tough, high-strength mass or lattice. The resulting PCD structure produces enhanced properties of wear resistance and hardness, making PCD materials extremely useful in aggressive wear and cutting applications where high levels of wear resistance and hardness are desired.
An example of a prior art PDC bit having a plurality of cutters with ultra hard working surfaces is shown in
A plurality of orifices 116 are positioned on the bit body 110 in the areas between the blades 120, which may be referred to as “gaps” or “fluid courses.” The orifices 116 are commonly adapted to accept nozzles. The orifices 116 allow drilling fluid to be discharged through the bit in selected directions and at selected rates of flow between the blades 120 for lubricating and cooling the drill bit 100, the blades 120 and the cutters 150. The drilling fluid also cleans and removes the cuttings as the drill bit 100 rotates and penetrates the geological formation. Without proper flow characteristics, insufficient cooling of the cutters 150 may result in cutter failure during drilling operations. The fluid courses are positioned to provide additional flow channels for drilling fluid and to provide a passage for formation cuttings to travel past the drill bit 100 toward the surface of a wellbore (not shown).
Referring to
A significant factor in determining the longevity of PDC cutters is the exposure of the cutter to heat. Exposure to heat can cause thermal damage to the diamond table and eventually result in the formation of cracks (due to differences in thermal expansion coefficients) which can lead to spalling of the polycrystalline diamond layer, delamination between the polycrystalline diamond and substrate, and conversion of the diamond back into graphite causing rapid abrasive wear. The thermal operating range of conventional PDC cutters is typically 700-750° C. or less.
As mentioned, conventional polycrystalline diamond is stable at temperatures of up to 700-750° C. in air, above which observed increases in temperature may result in permanent damage to and structural failure of polycrystalline diamond. This deterioration in polycrystalline diamond is due to the significant difference in the coefficient of thermal expansion of the binder material, cobalt, as compared to diamond. Upon heating of polycrystalline diamond, the cobalt and the diamond lattice will expand at different rates, which may cause cracks to form in the diamond lattice structure and result in deterioration of the polycrystalline diamond. Damage may also be due to graphite formation at diamond-diamond necks leading to loss of microstructural integrity and strength loss, at extremely high temperatures.
In conventional drag bits, PDC cutters are fixed onto the surface of the bit such that a common cutting surface contacts the formation during drilling. Over time and/or when drilling certain hard but not necessarily highly abrasive rock formations, the edge of the working surface on a cutting element that constantly contacts the formation begins to wear down, forming a local wear flat, or an area worn disproportionately to the remainder of the cutting element. Local wear flats may result in longer drilling times due to a reduced ability of the drill bit to effectively penetrate the work material and a loss of rate of penetration caused by dulling of edge of the cutting element. That is, the worn PDC cutter acts as a friction bearing surface that generates heat, which accelerates the wear of the PDC cutter and slows the penetration rate of the drill. Such flat surfaces effectively stop or severely reduce the rate of formation cutting because the conventional PDC cutters are not able to adequately engage and efficiently remove the formation material from the area of contact. Additionally, the cutters are typically under constant thermal and mechanical load. As a result, heat builds up along the cutting surface, and results in cutting element fracture. When a cutting element breaks, the drilling operation may sustain a loss of rate of penetration, and additional damage to other cutting elements, should the broken cutting element contact a second cutting element.
Additionally, the generation of heat at the cutter contact point, specifically at the exposed part of the PDC layer caused by friction between the PCD and the work material, causes thermal damage to the PCD in the form of cracks which lead to spalling of the polycrystalline diamond layer, delamination between the polycrystalline diamond and substrate, and back conversion of the diamond to graphite causing rapid abrasive wear. The thermal operating range of conventional PDC cutters is typically 750° C. or less.
Accordingly, there exists a continuing need for developments in improving the life of cutting elements.
This summary is provided to introduce a selection of concepts that are further described below 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.
In one aspect, embodiments disclosed herein relate to a cutting element assembly that includes a sleeve having a first inner diameter and a second inner diameter, wherein the second inner diameter is larger than the first inner diameter and located at a lower axial position than the first inner diameter. The cutting element also has a rotatable cutting element with an axis of rotation extending therethrough, a cutting face and a body extending axially downward from the cutting face, wherein the body has a shaft, and wherein the shaft is disposed within the sleeve, and a circumferential groove formed around an outer surface of the shaft. At least one retaining ring is disposed in the circumferential groove, wherein the at least one retaining ring extends at least around the entire circumference of the shaft, and wherein the at least one retaining ring protrudes from the circumferential groove, thereby retaining the rotatable cutting element within the sleeve.
In another aspect, embodiments disclosed herein relate to a cutting element assembly that includes a sleeve and a rotatable cutting element having an axis of rotation extending therethrough. The rotatable cutting element has a cutting face and a body extending axially downward from the cutting face, wherein at least a portion of the body is disposed within the sleeve. A circumferential groove is formed around an outer surface of the body, wherein the circumferential groove is located axially downward from the sleeve. At least one retaining ring is disposed in the circumferential groove, wherein the at least one retaining ring extends at least around the entire circumference of the body, and wherein the at least one retaining ring protrudes from the circumferential groove, thereby retaining the rotatable cutting element within the sleeve.
Other aspects and advantages of the disclosure will be apparent from the following description and the appended claims.
Embodiments of the present disclosure are described with reference to the following figures. The same numbers are used throughout the figures to reference like features and components.
Embodiments disclosed herein relate generally to rotatable cutting elements and methods of retaining such rotatable cutting elements on a drill bit or other cutting tools. Rotatable cutting elements of the present disclosure, also referred to as rolling cutters herein, may be retained on fixed cutter drill bits using one or more retaining rings and a sleeve having multiple inner radii. Advantageously, retaining rings and the sleeves described herein allow a rolling cutter to rotate as it contacts the formation to be drilled, while at the same time retaining the rolling cutter on the drill bit.
The cutting face 202 may be formed of diamond or other ultra-hard material. For example, a diamond material may extend a thickness of about 0.06 inches to about 0.15 inches from the cutting face into the rolling cutter, across the entire cutting face to form a diamond cutting table (not shown). In other embodiments, a rolling cutter may have a diamond or other ultra-hard material table having a thickness ranging from about 0.04 to 0.15 inches. Further, the cutting face may have a chamfer formed around the outer circumference, wherein the chamfer is not considered when measuring the thickness or diameter of the cutting table.
The rolling cutter 200 shown in
Referring now to
A cross-sectional view of the assembled cutting element is shown in
The sleeve 330 may have varying inner diameter sizes in addition to the first inner diameter Y1 and the second inner diameter Y2. For example, as shown in
The circumferential groove 310 formed around the outer surface of the rolling cutter body may be axially positioned along the shaft 308 so that the circumferential groove 310 abuts the transition 332 between the sleeve first inner diameter Y1 and second inner diameter Y2. In other words, the circumferential groove 310 and the sleeve second inner diameter Y2 both extend a distance in the same axial direction from the same axial position along the assembled cutting element. For example, as shown in
As assembled, the cutting element has a retaining ring 320 disposed in the circumferential groove 310, wherein the retaining ring 320 extends at least around the entire circumference of the shaft 308. For example, in the embodiment shown in
The location of the transition 322 as well as the location of the groove 310 may be selected to limit the cutter's 300 axial movement with respect to the sleeve 330, as well as to minimize or reduce the tendency of the cutter 300 to yank out of the sleeve (by limiting the cutter axial movement). Thus, referring to
Further, to ensure that the retaining ring can be properly installed between the sleeve and the cutter without weakening the retaining ring, the radial wall width h of the ring may be selected based on the cutter diameter x3 at the maximum groove depth as well as the first inner diameter Y1 of the sleeve, according to the following relationship: x3=Y1−2h, to ensure there is sufficient room in the groove 310 for the ring 320 to collapse into with it travels through the sleeve ID. Further, to ensure that the ring 320 is not plastically deformed when it travels through the sleeve ID, the ring's free (uncompressed OD, illustrated in
When installed, the retaining ring 320 may touch the second inner diameter Y2 of sleeve 330 in an uncompressed or slightly compressed state, i.e., the ring free (uncompressed) OD is at least equal to the second inner diameter Y2 of the sleeve, which is greater than the first inner diameter Y1. Further, the height H of the step of transition 322 may be selected based on the ring radial wall h such that H is at least one-tenth the ring radial wall h and no more than nine-tenths the ring radial wall h, i.e., 1/10 h≤H≤ 9/10 h. In one or more embodiments, H may be at least two-, three-, four-, or five-tenths the ring radial wall h as a lower limit, and no more than five-tenths, six-tenths, seven-tenths, or eight-tenths the ring radial wall h as an upper limit, where any lower limit may be used with any upper limit. Further, it is also noted that in one or more embodiments, the distance p of the cutter 300 rearward of the groove 310 location is at least 0.030 inches, or at least 0.045 or 0.060 inches in other embodiments. Selection of the distance p may be based, in part, on the diameter X4 of the cutter 300 rearward of the groove 310 location. For example, in some embodiments, the diameter x4 of the cutter 300 rearward of the groove 310 location may be less than the diameter X2 of the shaft 308, in which case a greater p may be selected. P and X4 may be selected to minimize or avoid contact between the sleeve 330 at any points along its second inner diameter Y2 and the cutter rearward of the groove. Such considerations may be particularly relevant when the sleeve includes a slotted groove therein for the ring, instead of a stepped transition, as illustrated in
Retaining rings used in embodiments of the present disclosure may include closed loop rings. For example, referring to
Further, retaining rings may be planar or non-planar. For example,
Retaining rings of the present disclosure may be retained within a circumferential groove formed between a rolling cutter and a sleeve. The circumferential groove may have dimensions to ensure that the rolling cutter is locked within the sleeve.
Referring now to
Referring now to
Referring now to
Cutting element assemblies of the present disclosure may be assembled by installing a retaining ring around a rolling cutter prior to installing the rolling cutter within a sleeve or by installing a retaining ring within a sleeve prior to installing the rolling cutter within the sleeve. For example, as shown in
Further, according to embodiments of the present disclosure, more than one retaining ring may be used to retain a rolling cutter within a sleeve. For example,
According to embodiments of the present disclosure, retaining rings may be made of, for example, cermets, metals, or composite materials. For example, retaining ring material may include carbides, nitrides, borides, and/or materials including ultra hard materials, such as diamond or cubic boron nitride. In other examples, retaining ring material may include metal alloys including, for example, carbon steel, stainless steel, aluminum, titanium, austenitic nickel-chromium-based superalloys, or beryllium copper alloys. It is also envisioned that the ring may be non-metallic (such as polymeric or carbon fiber based). One or more embodiments may incorporate a coating or surface treatment (such as heat treatment or carburization) to reduce or prevent corrosion and/or to increase the wear resistance and surface hardness. The selection of the materials may be based, in part on the desired properties as well as the desired dimensions of the ring and cutter assembly components. Specifically, in one or more embodiments, it may be desirable for the ring to have a thrust load capacity based on ring shear of at least 500 pounds, or at least 1000, 1500, 2000, or 2500 pounds in yet other embodiments. Further, the allowable thrust load of the ring will be based on the sleeve diameter at the ring location (Y1 shown in
Retaining ring material may be in the form of a wire, which may be wound more than a single turn to form a closed loop ring, wherein the retaining ring material has unattached ends. Alternatively, retaining ring material may be cast or machined into a closed loop ring, or may have attached ends. Various forms of retaining rings according to embodiments of the present disclosure are described below with reference to assembled cutting elements.
Referring now to
The transition 832 from the first inner diameter Y1 to second inner diameter Y2 and the circumferential groove 810 are axially positioned in the assembled cutting element to align so that the retaining ring 820 may protrude from the circumferential groove 810 to contact the transition 832. Particularly, upon inserting the rolling cutter 800 and retaining ring 820 into the sleeve, the retaining ring 820 may protrude from the rolling cutter 800 a distance to rotatably contact the second inner diameter Y2 of the sleeve 830, and prevent the rolling cutter 800 from sliding out of the sleeve 830. While the retaining ring may protrude to contact a larger inner diameter in the sleeve, the retaining ring (in uncompressed form) may be too large to fit through the smaller inner diameter in the sleeve, thereby retaining the rolling cutter within the sleeve. It is also envisioned that any of the retaining rings of the present disclosure need not be so large to contact the larger inner diameter, so long as it is larger than the smaller inner diameter in the sleeve.
As shown, a non-planar retaining ring 820 is disposed within the circumferential groove 810. The non-planar retaining ring 820 may have an undulating shape, such as shown in
Referring now to
The rolling cutter 1000 has a cutting face 1002 and a body 1004 extending axially therefrom, wherein the body 1004 includes a shaft 1008 having a diameter X2 smaller than the diameter X1 of the cutting face 1002. The sleeve 1030 has a first inner diameter Y1 and a larger second inner diameter Y2. Although the sleeve 1030 is shown as having the second inner diameter Y2 axially extend from the first inner diameter Y1 to the bottom 1035 of the sleeve, other embodiments may have a sleeve with a second inner diameter that extends downward, a partial axial distance towards the bottom of the sleeve. For example, a sleeve may have a second inner diameter (larger than the first inner diameter) extend from the first inner diameter to a third inner diameter, which is smaller than the second inner diameter, thereby forming a channel within the inner surface of the sleeve that may receive a protruding retaining ring. For example, as shown in
Referring again to
As shown, the spring 1040 may protrude from the circumferential groove 1010 farther than the retaining ring 1020. Alternatively, a spring may protrude from the circumferential groove a distance equal to or smaller than the distance the retaining ring protrudes from the circumferential groove. The cutting element in
Further, as shown, the retaining ring 1120 and the spring 1140 may extend different distances from within the circumferential groove 1110. For example, the spring 1140 may radially extend the depth of the circumferential groove 1110 to the outer surface 1106 of the shaft 1108, such that the spring 1140 may fit through a smaller first inner diameter Y1 of the sleeve 1130, while the retaining ring 1120 (in expanded form) may protrude from the circumferential groove 1110 a distance farther than the spring 1140 to contact a larger second inner diameter Y2 of the sleeve 1130. However, according to some embodiments, a retaining ring (in expanded form) may protrude from the circumferential groove a distance farther than the spring without contacting the larger second inner diameter of the sleeve.
According to embodiments of the present disclosure, a cutting element such as the one shown in
Referring now to
The spring 1240 shown in
Advantageously, by using one or more springs with a rolling cutter partially disposed in a sleeve, appropriate contact along the axial bearings between the rolling cutter and sleeve top opening may be maintained to prevent debris from entering between the rolling cutter and sleeve. Particularly, axial bearings within cutting elements of the present disclosure may refer to the interfacing surfaces of the portion of the rolling cutter that is outside the sleeve and the top surface of the sleeve opening. For example, as shown in
Additionally, a spring may improve rotatability of the rolling cutter within the sleeve. For example, as shown in
Springs used in the present disclosure may have varying values of compressibility. For example, a spring may have a spring constant ranging from a lower limit of any of 10 lb/in, 30 lb/in, and 50 lb/in to an upper limit of any of 50 lb/in, 70 lb/in, 100 lb/in, or greater than 100 lb/in, where any lower limit can be used in combination with any upper limit. Further, springs may be made of the same material as a retaining ring, or a different material than a retaining ring. For example, springs may be made of a metal, alloys, composite materials, stainless steels, or other material capable of withstanding wear and corrosion.
Furthermore, the sleeves shown in
Referring now to
The slits 1325 formed in the retaining ring 1320 may provide the retaining ring 1320 with spring action. Particularly, by providing slits 1325 axially along a partial height h of the retaining ring 1320, the retaining ring 1320 may act as a spring, which may be radially compressed and spring radially outward along the partial height h of the slits 1325. Advantageously, by extending radially outward to contact the larger inner diameter Y2 of the sleeve 1330, the retaining ring 1320 may axially maintain the rolling cutter 1300 tight against the sleeve 1330, which may reduce or prevent debris from entering between the rolling cutter 1300 and the sleeve 1330, while also radially maintaining the rolling cutter 1300 within the center of the sleeve 1330.
Referring now to
Each of the embodiments described herein may have at least one ultra hard material included therein. Such ultra hard materials may include a conventional polycrystalline diamond table (a table of interconnected diamond particles having interstitial spaces therebetween in which a metal component (such as a metal catalyst) may reside), a thermally stable diamond layer (i.e., having a thermal stability greater than that of conventional polycrystalline diamond, 750° C.) formed, for example, by removing substantially all metal from the interstitial spaces between interconnected diamond particles or from a diamond/silicon carbide composite, or other ultra hard material such as a cubic boron nitride or any other super hard material including different carbides. For example, according to some embodiments, an ultra hard material table, such as polycrystalline diamond, may be used to form the cutting face and cutting edge of a rolling cutter. Further, in particular embodiments, various grades of diamond may be used, such as varying particle sizes or diamond density.
As known in the art, thermally stable diamond may be formed in various manners. A typical polycrystalline diamond layer includes individual diamond “crystals” that are interconnected. The individual diamond crystals thus form a lattice structure. A metal catalyst, such as cobalt, may be used to promote recrystallization of the diamond particles and formation of the lattice structure. Thus, cobalt particles are typically found within the interstitial spaces in the diamond lattice structure. Cobalt has a significantly different coefficient of thermal expansion as compared to diamond. Therefore, upon heating of a diamond table, the cobalt and the diamond lattice will expand at different rates, causing cracks to form in the lattice structure and resulting in deterioration of the diamond table. To obviate this problem, strong acids may be used to “leach” the cobalt from a polycrystalline diamond lattice structure (either a thin volume or entire tablet) to at least reduce the damage experienced from heating diamond-cobalt composite at different rates upon heating. Examples of “leaching” processes can be found, for example, in U.S. Pat. Nos. 4,288,248 and 4,104,344.
By leaching out the cobalt, thermally stable polycrystalline (TSP) diamond may be formed. In certain embodiments, only a select portion of a diamond composite is leached, in order to gain thermal stability without losing impact resistance. As used herein, the term TSP includes both of the above (i.e., partially and completely leached) compounds. Interstitial volumes remaining after leaching may be reduced by either furthering consolidation or by filling the volume with a secondary material, such by processes known in the art and described in U.S. Pat. No. 5,127,923, which is herein incorporated by this reference in its entirety.
Alternatively, TSP may be formed by forming the diamond layer in a press using a binder other than cobalt, one such as silicon, which has a coefficient of thermal expansion more similar to that of diamond than cobalt has. During the manufacturing process, a large portion, 80 to 100 volume percent, of the silicon reacts with the diamond lattice to form silicon carbide which also has a thermal expansion similar to diamond. Upon heating, any remaining silicon, silicon carbide, and the diamond lattice will expand at more similar rates as compared to rates of expansion for cobalt and diamond, resulting in a more thermally stable layer. PDC cutters having a TSP cutting layer have relatively low wear rates, even as cutter temperatures reach 1200° C. However, one of ordinary skill in the art would recognize that a thermally stable diamond layer may be formed by other methods known in the art, including, for example, by altering processing conditions in the formation of the diamond layer.
The substrate, or rolling cutter body, on which the cutting face is disposed may be formed of a variety of hard and/or ultra hard particles. In one embodiment, the body may be formed from a suitable material such as tungsten carbide, tantalum carbide, or titanium carbide. Additionally, various binding metals may be included in the body, such as cobalt, nickel, iron, metal alloys, or mixtures thereof. In the body, the metal carbide grains are supported within the metallic binder, such as cobalt. Additionally, the body may be formed of a sintered tungsten carbide composite structure. It is well known that various metal carbide compositions and binders may be used, in addition to tungsten carbide and cobalt. Thus, references to the use of tungsten carbide and cobalt are for illustrative purposes only, and no limitation on the type substrate or binder used is intended. In another embodiment, the body may also include a diamond ultra hard material such as polycrystalline diamond and thermally stable diamond. One of skill in the art should appreciate that it is within the scope of the present disclosure the cutting face and body are integral, identical compositions. Rolling cutters having an integral cutting face and body formed of identical compositions are shown, for example, in
Further, the sleeve may be formed from a variety of materials. In one embodiment, the sleeve may be formed of a suitable material such as tungsten carbide, tantalum carbide, or titanium carbide. Additionally, various binding metals may be included in the sleeve, such as cobalt, nickel, iron, metal alloys, or mixtures thereof, such that the metal carbide grains are supported within the metallic binder. In a particular embodiment, the sleeve is a cemented tungsten carbide with a cobalt content ranging from 6 to 13 percent. It is also within the scope of the present disclosure that the sleeve may also include more lubricious materials to reduce the coefficient of friction. The sleeve may be formed of such materials in its entirety or have a portions thereof (such as the inner surface) including such lubricious materials. For example, the sleeve may include diamond, diamond-like coatings, or other solid film lubricant. In other embodiments, the sleeve may be formed of alloy steels, nickel-based alloys, cobalt-based alloys, and/or high speed cutting tool steels.
Cutting elements of the present disclosure may be attached to a drill bit or other downhole cutting tool by attaching the sleeve of the cutting element to a cutter pocket formed in the tool by methods known in the art, such as by brazing. For example, a drill bit may have a bit body, a plurality of blades extending from the bit body, wherein each blade has a leading face, a trailing face, and a top side, and a plurality of cutter pockets disposed in the plurality of blades. According to some embodiments, blades may be formed of a boride, nitride, or carbide matrix material, such as a matrix material made of tungsten carbide and a binder, such as a metal from Group VIII of the Periodic Table. In some embodiments, the blades may also be impregnated with an ultrahard material, such as diamond. The cutter pockets may be formed in the top side of a blade, at the leading face, so that the cutting elements may contact and cut the working surface once disposed in the cutter pockets. A sleeve of a cutting element according to embodiments disclosed herein may be attached to one of the cutter pockets with or without a rotatable cutting element disposed therein. The sleeve may be attached to a bit body using a brazing process known in the art. Alternatively, in other embodiments of the present disclosure, a sleeve may be infiltrated or cast directly into the bit body during an infiltration or sintering process. The sleeve may have a first inner diameter and a second inner diameter, wherein the second inner diameter is larger than the first inner diameter.
As discussed above, a rotatable cutting element (inserted within the sleeve either before or after attachment to a cutter pocket), having an axis of rotation extending therethrough, may have a cutting face, a body extending downwardly from the cutting face, an outer surface, and a cutting edge formed at the intersection of the cutting face and the outer surface. A circumferential groove may be formed in the outer surface of the rotatable cutting element body, and at least one retaining ring may be disposed in the circumferential groove. The at least one retaining ring may protrude from the circumferential groove to contact the second inner diameter of the sleeve, thereby retaining the rotatable cutting element within the sleeve. Further, once attached to a blade, the cutting face of the rotatable cutting element may be flush with the leading face of the blade.
For example, referring to
The cutting elements of the present disclosure may be incorporated in various types of cutting tools, including for example, as cutters in fixed cutter bits or in reamers, or in other earth-boring tools. Bits having the cutting elements of the present disclosure may include a single rotatable cutting element with the remaining cutting elements being conventional cutting elements, all cutting elements being rotatable, or any combination therebetween of rotatable and conventional cutting elements.
In some embodiments, the placement of the cutting elements on the blade of a fixed cutter bit or cone of a roller cone bit may be selected such that the rotatable cutting elements are placed in areas experiencing the greatest wear. For example, in a particular embodiment, rotatable cutting elements may be placed on the shoulder or nose area of a fixed cutter bit. Additionally, one of ordinary skill in the art would recognize that there exists no limitation on the sizes of the cutting elements of the present disclosure. For example, in various embodiments, the cutting elements may be formed in sizes including, but not limited to, 9 mm, 13 mm, 16 mm, and 19 mm.
Further, one of ordinary skill in the art would also appreciate that various side rakes and back rakes may be used in various combinations. For example, in one embodiment, cutter side rakes may range from about −30° to +35°, and cutter back rakes may range from about 5° to 60°. A cutter may be positioned on a blade with a selected back rake to assist in removing drill cuttings and increasing rate of penetration. A cutter disposed on a drill bit with side rake may be forced forward in a radial and tangential direction when the bit rotates. In some embodiments, because the radial direction may assist the movement of rolling cutter relative to sleeve, such rotation may allow greater drill cuttings removal and provide an improved rate of penetration. One of ordinary skill in the art will realize that any back rake and side rake combination may be used with the cutting elements of the present disclosure to enhance rotatability and/or improve drilling efficiency.
As a cutting element contacts formation, the rotating motion of the cutting element may be continuous or discontinuous. For example, when the cutting element is mounted with a determined side rake and/or back rake, the cutting force may be generally pointed in one direction. Providing a directional cutting force may allow the cutting element to have a continuous rotating motion, further enhancing drilling efficiency.
Furthermore, by using closed loop retaining rings of the present disclosure to retain the rolling cutter within the sleeve, the life of the cutting element may be improved. Particularly, the closed loop retaining rings of the present disclosure may provide uniform loading between the rolling cutter and the sleeve (e.g., at the transition between the sleeve smaller inner diameter and larger inner diameter or the interfacing surface with the retaining ring). Additionally, using a closed loop retaining ring, as described herein, may improve rotatability of the rolling cutter within the sleeve, as the closed loop ring has a continuous surface to rotate about.
Referring now to
Furthermore, cutting elements of the present disclosure may be modified to be fixed, for example by brazing the rolling cutter to the sleeve, or may be modified to be indexable. For example, a rolling cutter shaft and corresponding inner shape of a sleeve may be modified to be non-cylindrical and axi-symmetrical, such that the rolling cutter may be manually removed from the sleeve and rotated an increment about the axis. Embodiments having a non-cylindrical and axi-symmetrical rolling cutter and corresponding sleeve may be indexable, for example, by 20°, 45°, 90°, 120°, or other incremental amounts less than 360°.
While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims.
This application is a continuation of U.S. patent application Ser. No. 15/466,446 filed Mar. 22, 2017, which is a continuation of U.S. patent application Ser. No. 13/972,465 filed Aug. 21, 2013, which claims the benefit of U.S. Patent Application No. 61/794,580 filed on Mar. 15, 2013, U.S. Patent Application No. 61/712,794 filed on Oct. 11, 2012, and U.S. Patent Application No. 61/691,653 filed on Aug. 21, 2012, all of which are herein incorporated by this reference in their entireties.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3499685 | Kniff et al. | Mar 1970 | A |
| 3512838 | Kniff et al. | May 1970 | A |
| 3690728 | Krekeler et al. | Sep 1972 | A |
| 4084856 | Emmerich | Apr 1978 | A |
| 4104344 | Pope et al. | Aug 1978 | A |
| 4247147 | Rettkowski | Jan 1981 | A |
| 4288248 | Bovenkerk et al. | Sep 1981 | A |
| 4553615 | Grainger | Nov 1985 | A |
| 4582364 | Demey, III | Apr 1986 | A |
| 4684176 | Den Besten et al. | Aug 1987 | A |
| 5018793 | Den Besten | May 1991 | A |
| 5127923 | Bunting et al. | Jul 1992 | A |
| 5415462 | Massa | May 1995 | A |
| 5655614 | Azar | Aug 1997 | A |
| 5678645 | Tibbitts et al. | Oct 1997 | A |
| 5730502 | Montgomery, Jr. | Mar 1998 | A |
| 5906245 | Tibbitts et al. | May 1999 | A |
| 6113195 | Mercier et al. | Sep 2000 | A |
| 6786557 | Montgomery, Jr. | Sep 2004 | B2 |
| 7338135 | Hall | Mar 2008 | B1 |
| 7703559 | Shen et al. | Apr 2010 | B2 |
| 7717523 | Weaver | May 2010 | B2 |
| 7762359 | Miess | Jul 2010 | B1 |
| 7837277 | Weaver | Nov 2010 | B2 |
| 8091655 | Shen et al. | Jan 2012 | B2 |
| 8267483 | Kramer et al. | Sep 2012 | B2 |
| 8413746 | Shen et al. | Apr 2013 | B2 |
| 8727043 | Zhang et al. | May 2014 | B2 |
| 8881849 | Shen et al. | Nov 2014 | B2 |
| 8991523 | Shen et al. | Mar 2015 | B2 |
| 9187962 | Burhan et al. | Nov 2015 | B2 |
| 9322219 | Burhan et al. | Apr 2016 | B2 |
| 9328564 | Zhang et al. | May 2016 | B2 |
| 9464486 | Zhang et al. | Oct 2016 | B2 |
| 9605486 | Burhan | Mar 2017 | B2 |
| 9624731 | Haugvaldstad et al. | Apr 2017 | B2 |
| 9976356 | Burhan | May 2018 | B2 |
| 20040118615 | Beach | Jun 2004 | A1 |
| 20060006727 | Frear | Jan 2006 | A1 |
| 20060033379 | Frear | Feb 2006 | A1 |
| 20060260846 | Portwood et al. | Nov 2006 | A1 |
| 20060261663 | Sollami | Nov 2006 | A1 |
| 20070144789 | Johnson et al. | Jun 2007 | A1 |
| 20070205023 | Hoffmaster et al. | Sep 2007 | A1 |
| 20070278017 | Shen et al. | Dec 2007 | A1 |
| 20080115978 | Hall et al. | May 2008 | A1 |
| 20080202819 | Fader | Aug 2008 | A1 |
| 20090205870 | Smith | Aug 2009 | A1 |
| 20090284069 | Watson et al. | Nov 2009 | A1 |
| 20100108403 | Keshavan | May 2010 | A1 |
| 20100218999 | Jones et al. | Sep 2010 | A1 |
| 20100219001 | Shen et al. | Sep 2010 | A1 |
| 20100314176 | Zhang et al. | Dec 2010 | A1 |
| 20110241407 | Fader et al. | Oct 2011 | A1 |
| 20110284293 | Shen et al. | Nov 2011 | A1 |
| 20120073881 | Shen et al. | Mar 2012 | A1 |
| 20120273280 | Zhang et al. | Nov 2012 | A1 |
| 20120273281 | Burhan et al. | Nov 2012 | A1 |
| 20130169022 | Monyak et al. | Jul 2013 | A1 |
| 20130199857 | Schwefe et al. | Aug 2013 | A1 |
| 20130220707 | Shen et al. | Aug 2013 | A1 |
| 20130333953 | Zhang et al. | Dec 2013 | A1 |
| 20140054094 | Burhan et al. | Feb 2014 | A1 |
| 20140339882 | Hall et al. | Nov 2014 | A1 |
| 20140360792 | Azar et al. | Dec 2014 | A1 |
| 20170191317 | Burhan et al. | Jul 2017 | A1 |
| Number | Date | Country |
|---|---|---|
| 2216137 | Dec 1995 | CN |
| 1155315 | Jul 1997 | CN |
| 1651711 | Aug 2005 | CN |
| WO9605404 | Feb 1996 | WO |
| WO2017087920 | May 2017 | WO |
| Entry |
|---|
| International Search Report and Written Opinion issued in International Patent Application No. PCT/US2016/052727 dated Jan. 6, 2017, 16 pages. |
| International Search Report and Written Opinion issued in International Patent Application No. PCT/US2013/051317 dated Oct. 8, 2013, 14 pages. |
| International Preliminary Report on Patentability issued in International Patent Application No. PCT/US2013/051317 dated Feb. 24, 2015, 12 pages. |
| First Office Action and Search report issued in Chinese Patent Application No. 201380049452.2 dated Nov. 30, 2015, 25 pages. |
| Second Office Action report issued in Chinese Patent Application No. 201380049452.2 dated May 23, 2016, 6 pages. |
| Third Office Action issued in Chinese Patent Application No. 201380049452.2 dated Nov. 30, 2016, 6 pages. |
| Office Action issued in U.S. Appl. No. 13/972,465 dated Nov. 6, 2015, 14 pages. |
| Office Action issued in U.S. Appl. No. 13/972,465 dated Apr. 18, 2016, 18 pages. |
| Office Action issued in U.S. Appl. No. 13/972,465 dated Aug. 25, 2016, 8 pages. |
| Office Action issued in U.S. Appl. No. 15/466,446 dated May 19, 2017, 9 pages. |
| Office Action issued in U.S. Appl. No. 15/466,446 dated Oct. 20, 2017, 7 pages. |
| Examination Report 94(3) EPC issued in European Patent Application No. 13757695.5 dated Nov. 24, 2015, 5 pages. |
| Search Report R 61 issued in European Patent Application No. 13757695.5 dated Nov. 2, 2015, 3 pages. |
| International Search Report and Written Opinion issued in International Patent Application No. PCT/US2013/029771 dated Jun. 4, 2013, 12 pages. |
| International Preliminary Report on Patentability issued in International Patent Application No. PCT/US2013/029771 dated Sep. 18, 2014, 9 pages. |
| Office Action issued in U.S. Appl. No. 13/786,085 dated May 4, 2015, 7 pages. |
| Office Action issued in U.S. Appl. No. 13/786,085 dated Sep. 21, 2015, 6 pages. |
| First Office Action and Search Report issued in Chinese Patent Application No. 201380021302.0 dated Aug. 24, 2015, 25 pages. |
| Second Office Action and Search Report issued in Chinese Patent Application No. 201380021302.0 dated May 12, 2016, 25 pages. |
| Number | Date | Country | |
|---|---|---|---|
| 20180258708 A1 | Sep 2018 | US |
| Number | Date | Country | |
|---|---|---|---|
| 61794580 | Mar 2013 | US | |
| 61712794 | Oct 2012 | US | |
| 61691653 | Aug 2012 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 15466446 | Mar 2017 | US |
| Child | 15981225 | US | |
| Parent | 13972465 | Aug 2013 | US |
| Child | 15466446 | US |
