Earth-boring tools having pockets trailing rotationally leading faces of blades and having cutting elements disposed therein and related methods

An earth-boring tool may include a plurality of blades extending axially and radially from a body. A first plurality of cutting elements may be disposed along rotationally leading faces of the plurality of blades. A pocket may be formed within a blade, and the pocket may extend angularly into the blade from a rotationally leading face of the blade within a shoulder region of the blade. A second plurality of cutting elements may be disposed within the at least one pocket. A ratio of a cutting profile height of the earth-boring tool and a diameter of the earth-boring tool may be within a range of about 0.15 and about 0.25. A rotational pathway of at least one cutting element of the second plurality of cutting elements may at least partially overlaps with another rotational pathway of at least one cutting element of the first plurality of cutting elements.

TECHNICAL FIELD

This disclosure relates generally to earth-boring tools having pockets defined in one or more blades of the earth-boring tools.

BACKGROUND

Oil wells (wellbores) are usually drilled with a drill string. The drill string includes a tubular member having a drilling assembly that includes a single drill bit at its bottom end. The drilling assembly may also include devices and sensors that provide information relating to a variety of parameters relating to the drilling operations (“drilling parameters”), behavior of the drilling assembly (“drilling assembly parameters”) and parameters relating to the formations penetrated by the wellbore (“formation parameters”). A drill bit and\or reamer attached to the bottom end of the drilling assembly is rotated by rotating the drill string from the drilling rig and/or by a drilling motor (also referred to as a “mud motor”) in the bottom hole assembly (“BHA”) to remove formation material to drill the wellbore.

BRIEF SUMMARY

Some embodiments of the present disclosure include earth-boring tools. The earth-boring tools may include a body including a plurality of blades, each blade of the plurality of blades extending axially and radially relative to a center longitudinal axis of the body, at least one blade of the plurality of blades having a pocket extending into the at least one blade from a rotationally leading face of the at least one blade in at least a shoulder region of the at least one blade. The earth-boring tools may further include a first plurality of cutting elements secured along rotationally leading faces of the plurality of blades and a second plurality of cutting elements secured to the at least one blade of the plurality of blades proximate a back surface of the at least one pocket, wherein a ratio of a cutting profile height of the earth-boring tool and a diameter of the earth-boring tool is within a range of about 0.15 and about 0.25.

In additional embodiments, the earth-boring tool may include a body including a plurality of blades, each blade of the plurality of blades extending axially and radially relative to a center longitudinal axis of the body, at least one blade of the plurality of blades having a pocket extending into the at least one blade from a rotationally leading face of the at least one blade in at least a shoulder region of the at least one blade. The earth-boring tools may also include a first plurality of cutting elements secured along rotationally leading faces of the plurality of blades and a second plurality of cutting elements secured to the at least one blade of the plurality of blades proximate a back surface of the at least one pocket, wherein a rotational pathway of at least one cutting element of the second plurality of cutting elements defined by a full rotation of the earth-boring tool at least partially overlaps with another rotational pathway of at least one cutting element of the first plurality of cutting elements.

Some embodiments of the present disclosure include a method of forming an earth-boring tool. The method may include forming a body of an earth-boring tool including a plurality of blades and having at least one pocket in at least one blade of the plurality of blades, the at least one pocket extending into the at least one blade from a rotationally leading face of the at least one blade within a shoulder region of the at least one blade; securing a first plurality of cutting elements along rotationally leading faces of the plurality of blades; and securing a second plurality of cutting elements to the at least one blade proximate a back surface of the at least one blade wherein a rotational pathway of at least one cutting element of the second plurality of cutting elements defined by a full rotation of the earth-boring tool at least partially overlaps with another rotational pathway of at least one cutting element of the first plurality of cutting elements.

DETAILED DESCRIPTION

The illustrations presented herein are not actual views of any drill bit or any component thereof, but are merely idealized representations, which are employed to describe embodiments of the present invention.

As used herein, the terms “earth-boring tool” mean and include earth-boring tools for forming, enlarging, or forming and enlarging a borehole. Non-limiting examples of bits include fixed cutter (drag) bits, fixed cutter coring bits, fixed cutter eccentric bits, fixed cutter bi-center bits, fixed cutter reamers, expandable reamers with blades bearing fixed cutters, and hybrid bits including both fixed cutters and rotatable cutting structures (roller cones).

As used herein, the term “cutting structure” means and includes any element or feature that is configured for use on an earth-boring tool and for removing formation material from the formation within a wellbore during operation of the earth-boring tool.

As used herein, the term “cutting elements” means and includes, for example, superabrasive (e.g., polycrystalline diamond compact or “PDC”) cutting elements employed as fixed cutting elements, as well as tungsten carbide inserts and superabrasive inserts employed as cutting elements mounted to a body of an earth-boring tool.

As used herein, any relational term, such as “first,” “second,” “top,” “bottom,” “upper,” “lower,” etc., is used for clarity and convenience in understanding the disclosure and accompanying drawings, and does not connote or depend on any specific preference or order, except where the context clearly indicates otherwise. For example, these terms may refer to an orientation of elements of an earth-boring tool when disposed within a borehole in a conventional manner. Furthermore, these terms may refer to an orientation of elements of an earth-boring tool when as illustrated in the drawings.

As used herein, the term “about” used in reference to a given parameter is inclusive of the stated value and has the meaning dictated by the context (e.g., it includes the degree of error associated with measurement of the given parameter, as well as variations resulting from manufacturing tolerances, etc.).

As used herein, the term “cutting profile” refers to a two-dimensional representation of the profile of the cutting elements of the earth-boring tool that is defined by rotating all cutting elements of the earth-boring tool about a central longitudinal axis of the earth-boring tool and into a common plane on one half of the body of the tool.

As used herein, the term “cutting profile height” refers to an axial length (e.g., a length along an axial length of the earth-boring tool) between a bottom of a nose region of the body of the earth-boring tool and a bottom of a gage region (i.e., an interface of a shoulder region and the gage region) of the blade.

Some embodiments of the present disclosure may include an earth-boring tool. The earth-boring tool may include a plurality of blades. The plurality of blades may include a first plurality of cutting elements secured to the blade along rotationally leading faces of the plurality of blades. At least one blade of the plurality of blades may include a pocket formed in the at least one blade within a shoulder region of the at least one blade. The pocket may house a second plurality of cutting elements. Furthermore, in one or more embodiments, one or more cutting elements of the second plurality of cutting elements may trail (e.g., trail in a rotational direction of the earth-boring tool) one or more cutting elements of the first plurality of cutting elements disposed at the rotationally leading face of the blade. Furthermore, a rotational pathway (defined by a rotation of the earth-boring tool) of at least one cutting element of the second plurality of cutting elements within the pocket may at least partially overlap a rotational pathway of a cutting element of the first plurality of cutting elements disposed at the rotationally leading face of the blade in which the pocket is defined.

One or more embodiments of the present disclosure may include an earth-boring tool having a cutting profile that is relatively shorter than earth-boring tools having a similar number of cutting elements. For example, a ratio of a cutting profile height of the earth-boring tool and a drill bit diameter of the earth-boring tool may be within a range of about 0.15 and about 0.35.

FIG. 1is a schematic diagram of an example of a drilling system100that may utilize the apparatuses and methods disclosed herein for drilling boreholes.FIG. 1shows a borehole102that includes an upper section104with a casing106installed therein and a lower section108that is being drilled with a drill string110. The drill string110may include a tubular member112that carries a drilling assembly114at its bottom end. The tubular member112may be made up by joining drill pipe sections or it may be a string of coiled tubing, for example. A drill bit116may be attached to the bottom end of the drilling assembly114for drilling the borehole102of a selected diameter in a formation118.

The drill string110may extend to a rig120at surface122. The rig120shown is a land rig120for ease of explanation. However, the apparatuses and methods disclosed equally apply when an offshore rig120is used for drilling boreholes under water. A rotary table124or a top drive may be coupled to the drill string110and may be utilized to rotate the drill string110and to rotate the drilling assembly114, and thus the drill bit116to drill the borehole102. A drilling motor126may be provided in the drilling assembly114to rotate the drill bit116. The drilling motor126may be used alone to rotate the drill bit116or to superimpose the rotation of the drill bit116by the drill string110. The rig120may also include conventional equipment, such as a mechanism to add additional sections to the tubular member112as the borehole102is drilled. A surface control unit128, which may be a computer-based unit, may be placed at the surface122for receiving and processing downhole data transmitted by sensors140in the drill bit116and sensors140in the drilling assembly114, and for controlling selected operations of the various devices and sensors140in the drilling assembly114. The sensors140may include one or more of sensors140that determine acceleration, weight on bit, torque, pressure, cutting element positions, rate of penetration, inclination, azimuth formation/lithology, etc. In some embodiments, the surface control unit128may include a processor130and a data storage device132(or a computer-readable medium) for storing data, algorithms, and computer programs134. The data storage device132may be any suitable device, including, but not limited to, a read-only memory (ROM), a random-access memory (RAM), a flash memory, a magnetic tape, a hard disk, and an optical disk. During drilling, a drilling fluid from a source136thereof may be pumped under pressure through the tubular member112, which discharges at the bottom of the drill bit116and returns to the surface122via an annular space (also referred as the “annulus”) between the drill string110and an inside sidewall138of the borehole102.

The drilling assembly114may further include one or more downhole sensors140(collectively designated by numeral140). The sensors140may include any number and type of sensors140, including, but not limited to, sensors generally known as the measurement-while-drilling (MWD) sensors or the logging-while-drilling (LWD) sensors, and sensors140that provide information relating to the behavior of the drilling assembly114, such as drill bit rotation (revolutions per minute or “RPM”), tool face, pressure, vibration, whirl, bending, and stick-slip. The drilling assembly114may further include a controller unit142that controls the operation of one or more devices and sensors140in the drilling assembly114. For example, the controller unit142may be disposed within the drill bit116(e.g., within a shank208and/or crown210of a bit body of the drill bit116). The controller unit142may include, among other things, circuits to process the signals from sensor140, a processor144(such as a microprocessor) to process the digitized signals, a data storage device146(such as a solid-state-memory), and a computer program148. The processor144may process the digitized signals, and control downhole devices and sensors140, and communicate data information with the surface control unit128via a two-way telemetry unit150.

FIG. 2Ais a side view of an earth-boring tool200that may be used with the drilling assembly114ofFIG. 1according to one or more embodiments of the present disclosure.FIG. 2Bis a bottom view of the earth-boring tool200ofFIG. 2A. Referring toFIGS. 2A and 2Btogether, in some embodiments, the earth-boring tool200may include a drill bit having a plurality of blades. In additional embodiments the earth-boring tool200may include a drill bit having at least one rotatable cutting structure in the form of a roller cone and a plurality of blades. For example, the earth-boring tool200may be a hybrid bit (e.g., a drill bit having both roller cones and blades). Furthermore, the earth-boring tool200may include any other suitable drill bit or earth-boring tool200having rotatable cutting structures and/or blades for use in drilling and/or enlarging a borehole102in a formation118(FIG. 1).

The earth-boring tool200may comprise a body202including a neck206, a shank208, and a crown210. In some embodiments, the bulk of the body202may be constructed of steel, or of a ceramic-metal composite material including particles of hard material (e.g., tungsten carbide) cemented within a metal matrix material. The body202of the earth-boring tool200may have an axial center defining a center longitudinal axis205that may generally coincide with a rotational axis of the earth-boring tool200. The center longitudinal axis205of the body202may extend in a direction hereinafter referred to as an “axial direction.”

The body202may be connectable to a drill string110(FIG. 1). For example, the neck206of the body202may have a tapered upper end having threads thereon for connecting the earth-boring tool200to a box end of a drilling assembly114(FIG. 1). The shank208may include a lower straight section that is fixedly connected to the crown210at a joint. In some embodiments, the crown210may include a plurality of blades214.

Each blade214of the plurality of blades214of the earth-boring tool200may include a first plurality of cutting elements230fixed thereto. The plurality of cutting elements230of each blade214may be located in a row along a profile of the blade214proximate a rotationally leading face232of the blade214. In some embodiments, the first plurality of cutting elements230of the plurality of blades214may include PDC cutting elements230. Moreover, the first plurality of cutting elements230of the plurality of blades214may include any suitable cutting element configurations and materials for drilling and/or enlarging boreholes.

The plurality of blades214may extend from the end of the body202opposite the neck206and may extend in both the axial and radial directions. Each blade214may have multiple profile regions as known in the art (cone, nose, shoulder, gage).

Fluid courses234may be formed between adjacent blades214of the plurality of blades214and may be provided with drilling fluid by ports located at the end of passages leading from an internal fluid plenum extending through the body202from a tubular shank208at the upper end of the earth-boring tool200. Nozzles238may be secured within the ports for enhancing direction of fluid flow and controlling flow rate of the drilling fluid. The fluid courses234extend to junk slots240extending axially along the longitudinal side of earth-boring tool200between blades214of the plurality of blades214.

As will be discussed in greater detail below in regard toFIG. 3, at least one blade of the plurality of blades214may include a pocket215formed in the at least one blade within a shoulder region of the at least one blade. The pocket215may house a second plurality of cutting elements231. Furthermore, in one or more embodiments, one or more cutting elements of the second plurality of cutting elements231may trail (e.g., trail in a rotational direction of the earth-boring tool) one or more cutting elements of the first plurality of cutting element230disposed at the rotationally leading face232of the blade214. For instance, within a cutting profile of the earth-boring tool200defined by the first plurality of cutting elements230disposed at the rotationally leading face232of the blade214and the second plurality of cutting elements231housed by the pocket215formed in the at least one blade, at least one cutting element231of the second plurality of cutting elements231may at least partially overlap with a cutting element of the first plurality of cutting elements230of the at least one blade214. For example, in some embodiments, between about 60% and about 100% of a single cutter profile of the at least one cutting element231of the second plurality of cutting elements231may overlap with a cutter profile of a cutting element of the first plurality of cutting elements230of the at least one blade214. In some embodiments, between about 80% and about 100% of a single cutter profile of the at least one cutting element231of the second plurality of cutting elements231may overlap with a cutter profile of a cutting element of the first plurality of cutting elements230of the at least one blade214. In further embodiments, between about 90% and about 100% of a single cutter profile of the at least one cutting element231of the second plurality of cutting elements231may overlap with a cutter profile of a cutting element of the first plurality of cutting elements230of the at least one blade214. In yet further embodiments, between about 95% and about 100% of a single cutter profile of the at least one cutting element231of the second plurality of cutting elements231may overlap with a cutter profile of a cutting element of the first plurality of cutting elements230of the at least one blade214. The pocket215and second plurality of cutting elements230,231are described in greater detail in regard toFIGS. 3 and 6.

FIG. 3is a perspective view of a pocket215formed within a blade214of an earth-boring tool200according to one or more embodiments of the present disclosure. In some embodiments, the pocket215may extend angularly into the blade214from rotationally leading face232of the blade214within a shoulder region of the blade214. As used herein, the shoulder region of the blade214may include a portion of the blade falling within an angle defined between a horizontal axis extending through a boundary of the gage region and the shoulder region and an interface between the shoulder region and the nose region of the blade and about an intersection of the horizontal axis and a longitudinal axis of the earth-boring tool200. In some embodiments, the angle may be within a range of about 5° and about 25°. For instance, the angle may be about 15°. Furthermore, the pocket215may extend angularly into the blade214in a direction opposite to a rotational direction of the earth-boring tool200. Furthermore, the pocket may extend radially inward (e.g., toward a center longitudinal axis205of the earth-boring tool200) from a radially outermost surface303of the blade214within the shoulder region of the blade214.

In some embodiments, the pocket215may include a back surface302and at least one side surface304. For instance, the pocket215may extend from the rotationally leading face232of the blade214and may terminate angularly at the back surface302of the pocket215. Furthermore, the pocket215may extend radially inward from the radially outermost surface303of the blade214and may terminate radially at the at least one side surface304. In one or more embodiments, the at least one side surface304may include two side surfaces extending from the rotationally leading face232of the blade214to the back surface302of the pocket215. Moreover, the two side surfaces may define an angle that is less than 180° therebetween. For instance, the two side surfaces may define an angle of about 150° therebetween. Regardless, the back surface302and at least one side surface304of the pocket215may be exposed to an environment surrounding the earth-boring tool200. In other words, the pocket215may be open.

In one or more embodiments, the at least one side surface304may define an angle with the rotationally leading face232of the blade of about 45° to about 60°. Moreover, the back surface302may define an angle with the rotationally leading face232of the blade214of about 30° to about 50°. For example, the back surface302may define an angle with the rotationally leading face232of the blade214of about 40°.

In some embodiments, the pocket215may extend angularly (i.e., angularly about a longitudinal axis) for about 15° to about 25° about the center longitudinal axis205(FIG. 2B) of the earth-boring tool200. In other words, an angle between a plane extending from the center longitudinal axis205(FIG. 2B) of the earth-boring tool200and along the rotationally leading face232of the blade214, and a plane extending from the center longitudinal axis205(FIG. 2B) of the earth-boring tool200to the interface between the side surface304and the back surface302of the pocket may be about 15° to about 25°. Put yet another way, the interface of the side surface304and the back surface302of the pocket215may trail the rotationally leading face232of the blade214along a direction of rotation of the earth-boring tool200by about 15° to about 25°.

In some embodiments, a portion of the pocket215may extend at least partially behind at least one cutting element230of the first plurality of cutting elements230disposed along the rotationally leading face232of the blade214along a rotational pathway defined by the at least one cutting element230during a rotation of the earth-boring tool200. Furthermore, as discussed above in regard toFIGS. 2A and 2B, the pocket215may house a second plurality of cutting elements231. Furthermore, a rotational pathway (defined by a rotation of the earth-boring tool) of at least one cutting element231of the second plurality of cutting elements231within the pocket215may at least partially overlap a rotational pathway of a cutting element230of the first plurality of cutting elements230disposed at the rotationally leading face232of the blade214in which the pocket215is defined. For instance, the rotational pathway of at least one cutting element231may overlap the rotational pathway of the cutting element230by any of the amounts described above. Put another way, within a cutting profile of the earth-boring tool200defined by the first and second pluralities of cutting elements230,231during a full rotation of the earth-boring tool200, at least one cutting element231housed by the pocket215may at least partially overlap with a cutting element230disposed at the rotationally leading face232of the blade214within which the pocket215is formed. Cutting elements231of the second plurality of cutting elements231that overlap with cutting elements of the first plurality of cutting elements230are referred to hereinafter as “shadow cutting elements233.” In some embodiments, the earth-boring tool200may include two or more shadow cutting elements233within a single pocket215of a single blade214.

In some embodiments, at least one cutting element231of the second plurality of cutting elements231disposed within the pocket215may be disposed within the shoulder region of the blade214, and at least one other cutting element231of the second plurality of cutting elements231may be disposed within a gage region of the blade214. Moreover, in one or more embodiments, cutting faces of the second plurality of cutting elements231may be at least substantially parallel to the back surface302of the pocket215. For instance, the back surface302(e.g., an angle of the back surface302relative to the rotationally leading face232of the blade214) may be determined (e.g., formed) based on a rake of the cutting faces of the second plurality of cutting elements231housed within the pocket215. In some embodiments, the second plurality of cutting elements231within the pocket215may have a back rake within a range of about 30° to about 50°. For example, the second plurality of cutting elements231within the pocket215may have a back rake of about 40°. The first plurality of cutting elements230disposed along the rotationally leading face232of the blade214may have a back rake within a range of about 25° to about 35°. For instance, the first plurality of cutting elements230disposed along the rotationally leading face232of the blade214may have a back rake of about 30°.

Referring toFIGS. 2A-3together, in one or more embodiments, the earth-boring tool200may include a pocket215(as described above) in each of a plurality of blades214of the earth-boring tool200. Additionally, in some embodiments, the earth-boring tool200may include pockets215formed in two or more blades214. In some instances, the earth-boring tool200may include pockets215formed in two, three, four, five, or six consecutive blades214. In further embodiments, the earth-boring tool200may include pockets215formed in three consecutive blades214of six total blades214of the earth-boring tool200. For instance, the earth-boring tool200may include pockets215formed in three consecutive (side-by-side) blades214having the uppermost (e.g., axially uppermost) cutting elements230of the first plurality of cutting elements230disposed within shoulder regions of the blades214. In additional embodiments, the earth-boring tool200may include pockets215formed in alternating blades214(e.g., every other blade214) of the earth-boring tool200. As is discussed in greater detail below in regard toFIGS. 5 and 6, the pockets215, as described herein, may enable an earth-boring tool200to include an increased number of cutting elements within a shoulder region of the earth-boring tool200while maintaining a relatively short cutting profile height to maintain stability and directional responsiveness in directional drilling without sacrificing durability.

FIG. 4shows a pocket215formed in a blade214of an earth-boring tool200according to another embodiment of the present disclosure. For example, the pocket215may include any of the pockets215described above in regard toFIGS. 2A-3; however, the pocket215may include a least one port402extending through the bit body and intersecting at least a portion of the pocket215, and a nozzle238may be may be secured within the at least one port402for enhancing direction of fluid flow and controlling flow rate of the drilling fluid.

In view of the foregoing, having a port extending through the bit body and intersecting the pocket215of the blade214may improve hydraulics and cooling of the earth-boring tool200within the shoulder regions of the blades214of the earth-boring tool200. Having improved hydraulics and cooling within the shoulder regions of the blades214may improve durability of the cutting elements in the shoulder regions of the blades214, which may lead to increased lifespans and costs savings.

FIG. 5shows a simplified schematic representation of a portion of a profile500of a blade214of an earth-boring tool200(FIG. 2A) according to an embodiment of the present disclosure. The profile500may include a cone line502, a nose arc504, a shoulder arc506, and a gage line508. As will be understood by one of ordinary skill in the art, the cone line502may extend through a cone region of the blade214, the nose arc504may extend throughout a nose region of the blade214, the shoulder arc506may extend through a shoulder region of the blade214, and the gage line508may extend along a gage region of the blade214.

As is shown inFIG. 5, a cutting profile height of a cutting profile510defined by the cutting elements of the blades214of the earth-boring tool200may include an axial length (e.g., a length along an axial length of the earth-boring tool200) between a bottom of the nose arc504of the blade214and a bottom of the gage line508(i.e., an interface of the shoulder arc506and the gage line508) of the blade214.

In some embodiments, a ratio of a cutting profile height of the earth-boring tool200(FIG. 2B) and a drill bit diameter of the earth-boring tool200(FIG. 2B) may be within a range of about 0.15 and about 0.35. In some embodiments, a ratio of a cutting profile height of the earth-boring tool and a diameter of the earth-boring tool is greater than about 0.15. For instance, the ratio may be within a range of about 0.15 and 0.25. As a non-limiting example, the ratio may be about 0.18. As a non-limiting example, in some embodiments, the cutting profile height may be about 1.56 inches and the drill bit diameter may be about 8.5 inches.

FIG. 6shows a schematic view of a cutting profile600defined by the first and second pluralities of cutting elements230,231(FIG. 2A) of the plurality of blades214(FIG. 2A) of the earth-boring tool200(FIG. 2A) according to one or more embodiments of the present disclosure. Referring toFIGS. 2B and 6together, for purposes of the present disclosure, the plurality of blades214of the earth-boring tool200depicted inFIG. 2Bwill be numbered and described with references to those numbers in order to facilitate description of certain aspects of the earth-boring tool200. For example, the earth-boring tool200may include six numbered blades.

With reference toFIG. 2B, blade No. 1 may be oriented in a generally 3:00 o'clock position. Moving clockwise around the earth-boring tool200, blade No. 2 may include a next rotationally adjacent blade to blade No. 1. Additionally, blade No. 3 may include a next rotationally adjacent blade in the clockwise direction. Moreover, blade No. 4 may include a next rotationally adjacent blade in the clockwise direction. Likewise, blade No. 5 may include a next rotationally adjacent blade in the clockwise direction. Blade No. 6 may include a next rotationally adjacent blade in the clockwise direction.

As is represented inFIGS. 2B, 3, and 6, the shadow cutting elements233may be disposed within pockets215of three blades214of a total of six blades214of the earth-boring tool200. Furthermore, in some embodiments, the shadow cutting elements233may be disposed in an opposing kerfing configuration (e.g., in same radial position as a cutting element on an opposite blade). For instance, as shown inFIG. 6and with reference toFIG. 2B, shadow cutting element No. 37 may be disposed within a pocket of Blade No. 1 and may be disposed in an opposing kerfing configuration with cutting element No. 38 of the shoulder region of Blade No. 4. Furthermore, shadow cutting element No. 35 may be disposed within a pocket of Blade No. 2 and may be disposed in an opposing kerfing configuration with cutting element No. 36 of the shoulder region of Blade No. 5. Moreover, shadow cutting element No. 32 may be disposed within a pocket of Blade No. 3 and may be disposed in an opposing kerfing configuration with cutting element No. 33 of the shoulder region of Blade No. 6. In alternative embodiments, the shadow cutting elements233may be disposed in non-opposing kerfing configurations. Moreover, the shadow cutting elements233may be ground or unground as will be understood by one of ordinary skill in the art.

In view of the foregoing, the pocket215, as described herein, provides advantages over conventional earth-boring tools. For example, in comparison to earth-boring tools having longer (e.g., taller) cutting profiles, the earth-boring tool200of the present disclosure may increase shoulder durability by increasing cutting element density without sacrificing directional control, build-up rate potential, and vibration levels. For instance, the earth-boring tool200of the present disclosure increases stability and directional responsiveness of relatively shorter profiled earth-boring tools while improving shoulder region durability. Furthermore, the earth-boring tool200of the present disclosure increases drilling efficiency when drilling on an adjustable kick off sub (“AKO”) by decreasing bit body rubbing. For example, the earth-boring tool200of the present disclosure enables the earth-boring tool200to drill at a higher rate of penetration (“ROP”) in a lateral wall.

Furthermore, the earth-boring tool200of the present disclosure may include a higher number of face cutting elements per unit of cutting profile height, as defined above. As used herein, the term “face cutting elements” refers to cutting elements that are disposed on a leading edge of a blade and/or pocket and not to cutting elements disposed within a gage region of the blade. For instance, the earth-boring tool200of the present disclosure may include between about 18 and 20 face cutting elements per inch of cutting profile height in comparison to conventional longer profile earth-boring tools, which include about 15 cutting elements per inch of cutting profile height. For instance, the earth-boring tool200of the present disclosure may include about 18 cutting elements per inch of cutting profile height. As will be understood by one of ordinary skill in the art, the pockets215described herein may enable an earth-boring tool200to have a higher cutting element density in comparison to conventional earth-boring tools, which leads to improved durability without sacrificing stability or directional responsiveness. Furthermore, the number of cutting elements may vary depending on cutting element size, bit size, etc.

FIG. 7is a graph700showing workrates (W) of cutting elements of an earth-boring tool (e.g., earth-boring tool200) having a relatively shorter cutting profile in comparison to workrates of cutting elements of conventional earth-boring tools drilling on center in a new state and having relatively taller cutting profiles. As shown in the graph700, the workrates of correlating cutting elements are essentially the same. As a result, the earth-boring tool of the present disclosure performs essentially the same as the earth-boring tools having taller cutting profiles terms of workrate but has improved stability, improved directional responsiveness, reduced vibrations, and better build-up rate potential. Accordingly, the earth-boring tool of the present disclosure may lead to cost savings and a more durable earth-boring tool.

Referring toFIGS. 2A and 7together, in some embodiments, the earth-boring tool200may include four cutting elements between 0 and 1 inch from a center longitudinal axis of the earth-boring along a radius of the earth-boring tool. Additionally, the earth-boring tool200may include four face cutting elements between 1 inch and 2 inches from the center longitudinal axis of the earth-boring along the radius of the earth-boring tool performing work drilling on-center in new state. Moreover, the earth-boring tool200may include seven cutting elements between 2 inches and 3 inches from the center longitudinal axis of the earth-boring along the radius of the earth-boring tool performing work drilling on-center in new state. Furthermore, the earth-boring tool200may include twelve cutting elements between 3 inches and 4 inches from the center longitudinal axis of the earth-boring along the radius of the earth-boring tool performing work drilling on-center in new state. Also, the earth-boring tool may include about 7 cutting elements between 4 inches and 4.5 inches from the center longitudinal axis of the earth-boring along the radius of the earth-boring tool performing work drilling on-center in new state.

The disclosure further includes the following embodiments:

An earth-boring tool, comprising: a body including a plurality of blades, each blade of the plurality of blades extending axially and radially relative to a center longitudinal axis of the body, at least one blade of the plurality of blades having a pocket extending into the at least one blade from a rotationally leading face of the at least one blade in at least a shoulder region of the at least one blade; a first plurality of cutting elements secured along rotationally leading faces of the plurality of blades; and a second plurality of cutting elements secured to the at least one blade of the plurality of blades proximate a back surface of the at least one pocket, wherein a ratio of a cutting profile height of the earth-boring tool and a diameter of the earth-boring tool is within a range of about 0.15 and about 0.25.

The earth-boring tool of embodiment 1, wherein the earth-boring tool has a gauge diameter of about 8.75 inches and comprises at least 7 cutting elements between 4.0 inches and 4.5 inches from the center longitudinal axis of the earth-boring tool.

The earth-boring tool of embodiment 1, wherein the pocket comprises at least one side surface extending from the rotationally leading face of the at least one blade to the back surface of the at least one pocket.

The earth-boring tool of embodiment 3, wherein cutting faces of the second plurality of cutting elements are at least substantially parallel to the back surface of the pocket.

The earth-boring tool of embodiment 1, wherein the at least one blade of the plurality of blades comprises two or more blades, and the two or more blades are either located side-by-side, or alternating with other blades of the plurality of blades lacking a pocket.

The earth-boring tool of embodiment 1, wherein a pocket extends angularly into each of two or more of the blades, respectively, from a rotationally leading face to at least a shoulder region of each of the two or more blades.

The earth-boring tool of embodiment 1, wherein at least one cutting element of the second plurality of cutting elements is oriented in an opposing kerfing configuration with at least one cutting element disposed within a shoulder region of an opposite blade of the earth-boring tool.

The earth-boring tool of embodiment 1, wherein the ratio of the cutting profile height and the diameter of the earth-boring tool is about 0.18.

An earth-boring tool, comprising: a body including a plurality of blades, each blade of the plurality of blades extending axially and radially relative to a center longitudinal axis of the body, at least one blade of the plurality of blades having a pocket extending into the at least one blade from a rotationally leading face of the at least one blade in at least a shoulder region of the at least one blade; a first plurality of cutting elements secured along rotationally leading faces of the plurality of blades; and a second plurality of cutting elements secured to the at least one blade of the plurality of blades proximate a back surface of the at least one pocket; wherein a rotational pathway of at least one cutting element of the second plurality of cutting elements defined by a full rotation of the earth-boring tool at least partially overlaps with another rotational pathway of at least one cutting element of the first plurality of cutting elements.

The earth-boring tool of embodiment 9, wherein the at least one cutting element of the second plurality of cutting elements and the at least one cutting element of the first plurality of cutting elements are disposed on the same blade of the plurality of blades.

The earth-boring tool of embodiment 9, wherein a ratio of a cutting profile height of the earth-boring tool and a diameter of the earth-boring tool is within a range of about 0.15 and about 0.25.

The earth-boring tool of embodiment 9, wherein the pocket comprises at least one side surface extending from the rotationally leading face of the at least one blade to the back surface of the at least one pocket.

The earth-boring tool of embodiment 12, wherein cutting faces of the second plurality of cutting elements are at least substantially parallel to the back surface of the pocket.

The earth-boring tool of embodiment 9, wherein rotational pathways of at least two cutting elements of the second plurality of cutting elements at least partially overlap with respective rotational pathways of at least two cutting elements of the first plurality of cutting elements.

The earth-boring tool of embodiment 9, further comprising: a port extending through the bit body and intersecting the pocket; and a nozzle secured within the port.

The earth-boring tool of embodiment 9, wherein each cutting element of the second plurality of cutting elements has a back rake angle of at least about 30°.

The earth-boring tool of embodiment 9, wherein the at least one blade of the plurality of blades comprises two or more blades, and the two or more blades are either located side-by-side, or alternating with other blades of the plurality of blades lacking a pocket.

A method of forming an earth-boring tool, comprising: forming a body of an earth-boring tool including a plurality of blades and having at least one pocket in at least one blade of the plurality of blades, the at least one pocket extending into the at least one blade from a rotationally leading face of the at least one blade within a shoulder region of the at least one blade; securing a first plurality of cutting elements along rotationally leading faces of the plurality of blades; and securing a second plurality of cutting elements to the at least one blade proximate a back surface of the at least one pocket, wherein securing a first plurality of cutting elements and a second plurality of cutting elements further comprises locating at least one cutting element of the second plurality of cutting elements and at least one cutting element of the first plurality of cutting elements such that a rotational pathway of the at least one cutting element of the second plurality of cutting elements defined by a full rotation of the earth-boring tool at least partially overlaps with another rotational pathway of the at least one cutting element of the first plurality of cutting elements.

The method of embodiment 18, wherein forming the body of the earth-boring tool further comprises forming the body to have a cutting profile height, wherein a ratio of the cutting profile height of the earth-boring tool and a diameter of the earth-boring tool is within a range of about 0.15 and about 0.25.

The method of embodiment 18, further comprising securing at least one cutting element of the second plurality of cutting elements to be in an opposing kerfing configuration with at least one cutting element disposed within a shoulder region of an opposite blade.

The embodiments of the disclosure described above and illustrated in the accompanying drawings do not limit the scope of the disclosure, which is encompassed by the scope of the appended claims and their legal equivalents. Any equivalent embodiments are within the scope of this disclosure. Indeed, various modifications of the disclosure, in addition to those shown and described herein, such as alternate useful combinations of the elements described, will become apparent to those skilled in the art from the description. Such modifications and embodiments also fall within the scope of the appended claims and equivalents.