Embodiments of the present disclosure generally relate to earth-boring operations. In particular, embodiments of the present disclosure relate to earth-boring tools, nozzles, and associated structures, apparatus, and methods.
Wellbore drilling operations may involve the use of an earth-boring tool at the end of a long string of pipe commonly referred to as a drill string. An earth-boring tool may be used for drilling through formations, such as rock, dirt, sand, tar, etc. In some cases, the earth-boring tool may be configured to drill through additional elements that may be present in a wellbore, such as cement, casings (e.g., a wellbore casing), discarded or lost equipment (e.g., fish, junk, etc.), packers, etc. In some cases, earth-boring tools may be configured to drill through plugs (e.g., fracturing plugs, bridge plugs, cement plugs, etc.). In some cases, the plugs may include slips or other types of anchors and the earth-boring tool may be configured to drill through the plug and any slip, anchor, and other component thereof.
A fluid may be supplied into the wellbore during the wellbore drilling operation. The fluid may be used to cool and/or clean the earth-boring tool and/or related cutting elements. For example, the fluid may cool the earth-boring tool and carry cuttings and debris away from the earth-boring tool. Fluid pressure in the wellbore may be controlled to different pressures for different types of drilling operations. For example, in overbalanced drilling, the fluid pressure in the wellbore may be maintained above the pressure of the fluid in the earth formation to substantially prevent ingress of the fluids from the formation into the wellbore during the drilling operation. In some cases, the fluid pressure in the wellbore may be maintained below the fluid pressure of the formation. Lower fluid pressures may increase the efficiency of the drilling operation, however, this may allow fluid from the formation to enter the wellbore.
Embodiments of the disclosure include a nozzle for use in an earth-boring tool. The nozzle includes an inlet having a first size. The nozzle further includes an outlet having a second size different from the first size of the inlet. The nozzle also includes a fluid passage defined in the nozzle from the inlet to the outlet. The fluid passage includes a transition region configured to transition the fluid passage from the first size of the inlet to the second size of the outlet. The transition region includes a first frustoconical surface exhibiting a first arcuate shape curving inward; and a second frustoconical surface exhibiting a second arcuate shape curving outward.
Another embodiment of the disclosure includes an earth-boring tool. The earth-boring tool includes at least one blade including at least one cutting element. The earth-boring tool further includes at least one fluid course positioned adjacent the at least one blade. The earth-boring tool also includes a nozzle positioned in the at least one fluid course. The nozzle includes an inlet having a first size. The nozzle further includes an outlet having a second size different from the first size of the inlet. The nozzle also includes a fluid passage defined in the nozzle from the inlet to the outlet. The fluid passage includes a transition region configured to transition the fluid passage from the first size of the inlet to the second size of the outlet. The transition region includes an inlet transition point where a cross-section of the fluid passage begins to transition from the first size of the inlet. The transition region further includes an outlet transition point, where the cross-section of the fluid passage finishes transitioning to the second size of the outlet. The transition region also includes a transition length defined between the inlet transition point and the outlet transition point, where the transition length is between about ¼ and about ¾ of a total length of the fluid passage.
Other embodiments of the disclosure include a method of forming a nozzle for an earth-boring tool. The method includes forming a nozzle structure including an interface structure and an extension extending from the interface structure. The method further includes forming an inlet in the nozzle structure having a first size. The method also includes forming an outlet in the nozzle structure axially aligned with the inlet, the outlet having a second size different from the first size. The method further includes forming a fluid passage between the inlet and the outlet, the fluid passage extending axially through the nozzle structure. The method also includes forming a transition region in the fluid passage, the transition region configured to transition the fluid passage from the first size of the inlet to the second size of the outlet. The transition region includes a first frustoconical surface defining a first arc curving inward and a second frustoconical surface defining second arc curving outward.
While the specification concludes with claims particularly pointing out and distinctly claiming embodiments of the present disclosure, the advantages of embodiments of the disclosure may be more readily ascertained from the following description of embodiments of the disclosure when read in conjunction with the accompanying drawings in which:
The illustrations presented herein are not meant to be actual views of any particular earth-boring system or component thereof, but are merely idealized representations employed to describe illustrative embodiments. The drawings are not necessarily to scale.
As used herein, the term “earth-boring tool” means and includes any type of bit or tool used for drilling during the formation or enlargement of a wellbore in a subterranean formation. For example, earth-boring tools include fixed-cutter bits, roller cone bits, percussion bits, core bits, eccentric bits, bicenter bits, reamers, mills, drag bits, hybrid bits (e.g., rolling components in combination with fixed cutting elements), and other drilling bits and tools known in the art.
As used herein, the term “substantially” in reference to a given parameter means and includes to a degree that one skilled in the art would understand that the given parameter, property, or condition is met with a small degree of variance, such as within acceptable manufacturing tolerances. For example, a parameter that is substantially met may be at least about 90% met, at least about 95% met, at least about 99% met, or even at least about 100% met. In another example, an angle that is substantially met may be within about +/−15°, within about +/−10°, within about +/−5°, or even within about 0°.
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, relational terms, such as “first,” “second,” “top,” “bottom,” etc., are generally used for clarity and convenience in understanding the disclosure and accompanying drawings and do not connote or depend on any specific preference, orientation, or order, except where the context clearly indicates otherwise.
As used herein, the term “and/or” means and includes any and all combinations of one or more of the associated listed items.
As used herein, the singular forms following “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
As used herein, the term “may” with respect to a material, structure, feature, or method act indicates that such is contemplated for use in implementation of an embodiment of the disclosure, and such term is used in preference to the more restrictive term “is” so as to avoid any implication that other compatible materials, structures, features, and methods usable in combination therewith should or must be excluded.
As used herein, the terms “vertical” and “lateral” refer to the orientations as depicted in the figures.
During a drilling operation fluid may be supplied into the wellbore to cool and/or clean the earth-boring tool and related cutting elements. The pressure of the fluid in the wellbore may be used to substantially prevent reservoir fluids (e.g., fluids stored in the formation, such as gas, oil, water, etc.) from entering the wellbore during the drilling operation, this is commonly referred to as overbalance drilling. High fluid pressure in the wellbore may reduce the efficiency of the drilling operation. For example, maintaining the fluid pressure above the pressure of the reservoir fluids may increase the strength of the formation near the wall of the wellbore. The increased strength of the formation may reduce the efficiency of the drilling operation by reducing the cutting depth and rate of penetration (ROP) of the earth-boring tool.
The earth-boring tool 100 may rotate about a longitudinal axis of the earth-boring tool 100. When the earth-boring tool 100 rotates, the cutting face 112 of the cutting elements 108 may contact the earth formation and remove material. The material removed by the cutting faces 112 may then be removed through the fluid courses 104, in the industry the portion of the fluid courses 104 in a gage region of the earth-boring tool 100 are commonly referred to as junk slots. The earth-boring tool 100 includes nozzles 106 which may introduce fluid, such as water or drilling mud, into the area around the blades 102 to aid in removing the sheared material and other debris from the area around the blades 102 and/or to cool the cutting elements 108 and the blade 102 to increase the efficiency of the earth-boring tool 100.
The fluid may enter the wellbore through the nozzles 106. The nozzles 106 may be coupled to a pressurized fluid supplied through the drill string. The pressure of the fluid in the borehole may be controlled through the pressure of the fluid being supplied through the drill string and the nozzles 106. Reducing a distance between the nozzles 106 and a formation may facilitate weakening the material of the formation by infiltrating pores in the formation material with the fluid. In some embodiments, the nozzles 106 are configured to concentrate fluid flowing through the nozzles 106 through a jetting effect that may increase a pressure of the fluid contacting the formation and may weaken the material of the formation. For example, a formation's bulk strength may increase at greater depths due to a confining pressure. Delivering a high-pressure fluid directly onto the formation may locally weaken the bulk strength of the formation and cuttings, which may increase the amount of material removed, depth of cut, and/or rate of penetration of the associated earth-boring tool 100.
The nozzles 106 of the earth-boring tool 100, may be concentrated near a nose region 110 of the earth-boring tool 100. Positioning the nozzles 106 near the nose region 110 of the earth-boring tool 100 may facilitate reducing the strength of the formation immediately ahead of the earth-boring tool 100 during a drilling operation. In some embodiments, one or more of the nozzles 106 are directed to a shoulder region 120. In other embodiments, the nozzles 106 may be directed to both the nose region 110 and the shoulder region 120. In each configuration, the cutting elements 108 in the respective nose region 110 and/or shoulder region 120 may pass through a pressurized region of the formation where the mechanical cutting forces are reduced, which may result in an increased depth of cut, or rate of penetration.
In some embodiments, the nozzles 106 are positioned within the fluid courses 104 of the earth-boring tool 100. The nozzles 106 may include an extension 118 configured to position an outlet 116 of the nozzles 106 near the cutting elements 108 on an adjacent blade 102. For example, the extension 118 may position the outlet 116 within a cutting path of the cutting elements 108 defined by the circumference of the cutting faces 112 of the adjacent cutting elements 108. The extension 118 may extend away from a base of the associated fluid course 104 such that the outlet 116 is positioned close to the formation.
The nozzle 106 may be secured to the earth-boring tool 100 through an interface 306. The interface 306 may include interlocking threads that may facilitate removal, replacement, and/or changing the nozzle 106. In some embodiments, the interlocking threads of the interface 306 are tapered threads, such as pipe threads (e.g., NPT threads) that may form a substantially fluid tight seal when the nozzle 106 is tightened into place. In other embodiments, the interlocking threads of the interface may be straight threads. In some cases a secondary seal, such as an O-ring, may be positioned between the nozzle 106 and a surface of the earth-boring tool 100, such that when the nozzle 106 is tightened into place, the secondary seal is compressed between the nozzle 106 and the earth-boring tool 100 to form a substantially fluid tight seal. The secondary seal may be formed from a material having a high durometer (e.g., in a range from about 80 to about 90). The high durometer may facilitate forming a substantially fluid tight seal at fluid pressures in excess of 1500 psi. Drilling operations in different types of formations may be benefited by different sizes of outlets 116 on the nozzles 106. For example, a smaller outlet 116 may increase a velocity of the fluid leaving the nozzle 106, which may improve the penetration into formation materials having smaller pores, such as shale. Alternatively, a larger outlet 116 may increase the volume of fluid while reducing the velocity of the fluid, which may facilitate penetration of a larger amount of fluid into a more porous formation material, such as sandstone.
The nozzle 106 may include an inlet 308 on an opposite end of the nozzle 106 from the outlet 116. The inlet 308 may be coupled to fluid paths through the earth-boring tool 100, which may direct fluid from the drill string to the nozzles 106. The nozzle 106 may include a neck 310 positioned between the inlet 308 and the outlet 116. The neck 310 may reduce a cross-sectional diameter of the fluid path through the nozzle 106 from the size of the inlet 308 to at least the size of the outlet 116. Reducing the cross-sectional diameter of the fluid path through the nozzle 106 may provide a jetting effect accelerating the fluid passing through the nozzle 106, such that the fluid leaving the nozzle 106 through the outlet 116 is traveling at a higher rate of speed than the fluid entering the nozzle 106 through the inlet 308. The distance between the neck 310 and the outlet 116 may facilitate a stabilization of the speed of the fluid, such that the fluid exiting the outlet 116 may flow at a substantially uniform velocity greater than the velocity of the fluid entering the nozzle 106 through the inlet 308.
The fluid passage 400 may include a transition region 408 configured to transition from the size and/or shape of the inlet 404 to the size and/or shape of the outlet 402. The transition region 408 may include one or more features configured to contract the fluid passage 400 from the size and/or shape of the inlet 404 to the size and/or shape of the outlet 402, such as a funnel shape (e.g., a straight funnel or curved funnel). A straight funnel shape may have substantially straight sides forming a conical structure in the transition region 408. A curved funnel may include one or more curved converging surfaces defining a curved funnel shape in the transition region 408. The nozzles (e.g., nozzle 106 (
The transition region 408 illustrated in the embodiment of
A ratio of the size of the outlet 402 (e.g., radius of the outlet 402) to the first radius of the first arc 410 (e.g., the first radius of the first arc 410/the radius of the outlet 402) and the second radius of the second arc 412 (e.g., the second radius of the second arc 412/the radius of the outlet 402) may be in a range from about 2 to about 10, such as from about 4 to 9, or about 6 to about 8. For example, for an outlet having a diameter of about 0.25 inches (radius of about 0.125 in) the first radius of the first arc 410 and the second radius of the second arc 412 may each be about 1 in.
The transition region 408 may include multiple transition points in the wall 406 where two different geometric features defined by the wall 406 meet. At each transition point the joining geometric features may be substantially tangential to one another, such that the wall 406 at the transition point is substantially smooth with no abrupt geometric changes. In the embodiment illustrated in
The distance between the inlet transition point 422 and the outlet transition point 424 defines a transition length 414. The embodiments illustrated in
The fluid passages 400 may also include an outlet length 418 defining the distance between the outlet transition point 424 and the outlet 402. The fluid passage 400 in the outlet length 418 may have a substantially uniform cross-section having substantially a same size and shape as the outlet 402. The walls 406 between the outlet transition point 424 and the outlet length 418 may be configured to stabilize the fluid flow after the flow passes through the transition region 408. Increasing the outlet length 418 may provide greater stability to the fluid flow exiting the fluid passage 400 through the outlet 402. Increasing the outlet length 418 may also increase pressure losses in the fluid passage 400. The outlet length 418 may be determined based on a major dimension of the outlet 402. For example, the outlet length 418 may be in a range from about 1 times the diameter of the outlet 402 to about 5 times the diameter of the outlet 402, such as from about 1 times the diameter of the outlet 402 to about 3 times the diameter of the outlet 402.
In the embodiments of the nozzles 106 illustrated in
The fluid passage 500 may be configured to transition from the size and shape of the inlet 508 to the size and shape of the outlet 502 in substantially a same distance (e.g., the transition length 414 (
For example, in the embodiment illustrated in
In other embodiments, the radii of the associated first arc 512a, first arc 512b, second arc 514a, and second arc 514b may be substantially uniform, such that the transition length changes about the longitudinal axis 516 to accommodate the transition for the change of shape. In yet other embodiments, the inlet 508 may be formed to have a same cross-sectional shape as the outlet 502.
In some embodiments, nozzles 600 having different orifice 602 sizes are positioned in different positions about the earth-boring tool, such that the earth-boring tool has different pressure zones. For example, a nozzle 600 having a smaller orifice 602 may be positioned ahead of a first blade and a second nozzle 600 having a larger orifice 602 may be positioned ahead of a second blade. The first nozzle 600 may provide a fluid stream with a higher velocity than the second nozzle 600. As the earth-boring tool rotates the different nozzles 600 may generate an oscillating pressure on the formation.
The nozzles 600 may include tool interfaces 604 on the extension 608 of the nozzle 600. The tool interfaces 604 may facilitate the installation and removal of the nozzle 600. For example, the interfaces 610 on the nozzles 600 may be threads and the tool interfaces 604 on the respective nozzles 600 may facilitate coupling a wrench, socket or other tool to the extension 608 of the nozzle 600 to turn the nozzle 600 engaging the threads of the interface 610 to install or remove the nozzle 600. In some embodiments, the tool interface 604 may be configured to use specialized tooling, such that the nozzles 600 may not be removed without a specialized tool to prevent unauthorized removal of the nozzles 600.
In the embodiment illustrated in
In the embodiment illustrated in
Embodiments of the present disclosure may facilitate improved flow control through nozzles in an earth-boring tool. Improved flow control may increase an impact force and formation penetration of fluid flowing from the nozzles. This may cause the pore pressure in a formation to be artificially increased in a controlled area. Increasing the pore pressure of the formation may reduce the forces required to shear the formation and remove the material from the formation. This may reduce the power required to remove the material, reducing the power used in a drilling operation and/or increasing the speed with which the drilling may be performed.
Controlling the area where the pore pressure of the formation is artificially increased may enable a drilling operation to maintain the integrity of the wellbore through overbalanced drilling in the majority of the wellbore, while weakening the wall of the wellbore in a localized area to increase the efficiency of the material removal process. Increasing the efficiency of the material removal process may reduce the cost of drilling a wellbore. Increasing the efficiency of the material removal process may further reduce the amount of time before a wellbore may begin production and become a profitable wellbore.
The embodiments of the disclosure described above and illustrated in the accompanying drawing figures do not limit the scope of the invention, since these embodiments are merely examples of embodiments of the invention, which is defined by the appended claims and their legal equivalents. Any equivalent embodiments are intended to be within the scope of this disclosure. Indeed, various modifications of the present disclosure, in addition to those shown and described herein, such as alternative useful combinations of the elements described, may become apparent to those skilled in the art from the description. Such modifications and embodiments are also intended to fall within the scope of the appended claims and their legal equivalents.