TORSIONAL OSCIALLATION CONTROL TOOL GENERATING HIGH-AMPLITUDE AT VARIABLE FREQUENCIES
A lateral oscillation tool for using in a drill string performing a drilling operation includes a fluid driven, positive displacement motor and a rotating mandrel coupled to the positive displacement motor. At least one unbalanced mass is coupled to the rotating mandrel to generate lateral oscillation of the lateral oscillation tool. The unbalanced mass may include a plurality of tuning channels into which a high-density material may be selectively introduced to alter the positional mass of the unbalanced mass. When paired with the or variable electric drive motor turbine powered, lateral impact forces may be adjusted real-time and through the downhole adaptive learning software.
This application claims the priority of prior provisional U.S. Patent Application No. 63/027,409 filed on May 20, 2020, the contents of which being incorporated herein by reference in its entirety.
BACKGROUNDIn hydrocarbon exploration and production drilling operations, a wellbore is formed using a drill string to bore a hole into a subsurface formation. A drill string may include a bottom hole assembly having a drill bit attached a lower end of a string of tubular members. The tubular members may include drill collars, drill pipe, and other drilling tools. A drill string may extend thousands of meters from the surface. The drill string may be rotated from the surface, such as with a top drive, to advance the drill string into a formation. Directional wells may include vertical or near-vertical sections as well as horizontal or near-horizontal sections that kick off of from the vertical or near-vertical sections.
The present disclosure is best understood from the following detailed description when read with the accompanying figures, wherein:
It is emphasized that, in accordance with the standard practice in the industry, various features are not drawn to scale. In fact, the dimensions of the various features may be arbitrarily increased or reduced for clarity of discussion or illustration.
DETAILED DESCRIPTIONIllustrative examples of the subject matter claimed below are disclosed. In the interest of clarity, not all features of an actual implementation are described in this specification. It will be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions may be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort, even if complex and time-consuming, would be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure.
As used herein, the article “a” is intended to have its ordinary meaning in the patent arts, namely “one or more.” Herein, the term “about” when applied to a value generally means within the tolerance range of the equipment used to produce the value, or in some examples, means plus or minus 10%, or plus or minus 5%, or plus or minus 1%, unless otherwise expressly specified. Further, herein the term “substantially” as used herein means a majority, or almost all, or all, or an amount with a range of about 51% to about 100%, for example. Moreover, examples herein are intended to be illustrative only and are presented for discussion purposes and not by way of limitation.
As used herein, to “provide” an item means to have possession of and/or control over the item. This may include, for example, forming (or assembling) some or all of the item from its constituent materials and/or, obtaining possession of and/or control over an already-formed item.
In examples, top drive 110 may support and rotate drill string 108 as it advances through well head 112 to rotate a bottom hole assembly 114 including a drill bit 116 disposed at a distal end of drill string 108 to create a borehole 118. A pump 120 may circulate drilling fluid through a supply pipe 122 to top drive 110, through an interior of drill string 108 and various components thereof, as herein described, to exit through drill bit 116 and back to the surface through borehole 118 and into a retention pit 124. The drilling fluid may transport cuttings generated by drill bit 116 into retention pit 124, and the flow of drilling fluid through drill string 108 may actuate various tools incorporated into drill string 108 as herein described.
In examples, various tools and components incorporated into drill string 108 as described herein may communicate operational data to a surface receiver 126, such as with mud pulse telemetry, radio frequency telemetry, and the like. A control and computing system 128 may have a connection 130 to surface receiver to obtain and process operational data and to control operation of drilling system 100. Connection 130 may be a wireless or hardwired connection or a combination thereof.
According to one or more examples, among the components which may be included along the length of a drill string such as drill string 108 from the example of
Motor power section 204 of tool 200 is provided for rotating an unbalanced mass (as described herein) in unbalanced mass section 210. In some examples, motor power section 204 may include a fluid-driven positive displacement motor. In other examples, motor power section 204 may include a variable electric turbine powered motor receiving power and control signals through drill string 108.
An annulus 908 between flow diverter 900 and the inner wall of stator 500 permits the passage of fluid past threaded female coupling end 902. The fluid reaches flow diverter 900 after passage across rotor 600 to rotate rotor 600 and flex shaft 800. As indicated by arrow 910 in
With continued reference to
Mandrel 914 extends into an upper bearing housing 920 which is engaged with a threaded end coupling 922 of stator 500. A plurality of O-rings 924 may be provided for a fluid seal between upper bearing housing 920 and mandrel 914 as mandrel 914 rotates within upper thrust bearing 916 and lower thrust bearing 918. As herein described, in some examples the rotational rate of mandrel 914 may be determined in part by the rate of drilling fluid flow through drill string 108.
Further, unbalanced mass 1800 includes a plurality of cylindrical tuning channels 1810 formed therein. In examples, cylindrical tuning channels 1810 in unbalanced mass 1800 may be selectively filled with a high-density, high-weight filler material to alter the positional mass of unbalanced mass 1800. In examples, cylindrical tuning channels may be filled with materials such as tungsten, in the form of tungsten rods or powdered tungsten. In other examples, other high-density materials may be used. In examples where powdered or granular materials, such as powdered tungsten are introduced into one or more tuning channels 1810, a cap (not shown in the Figures) may be provided to seal the material in place.
In various examples, a first unbalanced mass 1800 may be installed on mandrel 914 in second intermediate section 1404 of mandrel 914. Steel rods (not shown in the Figures) may be installed in keyways 1410 of mandrel 914, to align with keyways 1812 of unbalanced mass 1800 such that unbalanced mass 1800 will rotate along with rotation of mandrel 914 during operation of lateral oscillation tool 200. Prior to installation, unbalanced mass 1800 may be tuned by selective introduction of high-density material into one or more of its tuning channels 1810. Thereafter, a second unbalanced mass 1800 may be installed on mandrel 914 in third intermediate section 1406. In various examples, the second unbalanced mass 1800 may be installed with its keyways 1812 aligned either with keyways 1412 of mandrel 914, or may be installed at a ninety-degree offset from the first unbalanced mass, with its keyways 1812 aligned with keyways 1414 of mandrel 914. Further, the second unbalanced mass 1800 may be tuned differently than the first unbalanced mass by having a different selected number of tuning channels 1810 filled with high-density material.
In examples, the selection of the relative orientation of two unbalanced masses 1800 installed on mandrel 914, as well as the selective tuning of each unbalanced mass 1800 through selective introduction of material into one or more of tuning channels 1810 gives rise to a wide range of possible oscillation frequencies and lateral oscillation forces generated by lateral oscillation tool 200. The oscillation forces and frequencies may be further modulated according to the flow rate of drilling fluid through lateral oscillation tool 200, which in turn modulates the speed of rotation of mandrel 914 caused by positive displacement motor power section 204.
As further shown in
In various examples, one or more lateral oscillation tools 200 may be incorporated into a drill string such as drill string 108 in order to induce lateral oscillation of drill string 108 according to desired oscillation characteristics. The desired oscillating characteristics can be tuned through adjustment of one or more variables, including: the number of lateral oscillation tools 200; the position of placement of one or more lateral oscillation tools 200 along the length of drill string 108 (taking into account the overall length of the drill string); the selection of which of the cylindrical tuning channels 1810 of each unbalanced mass 1800 to be populated with high-density material to alter the weight balance of the respective unbalanced mass; the orientation of each pair of unbalanced masses 1800 in a given lateral oscillation tool 200 (i.e., either in alignment or ninety-degrees offset, as described herein); the flow rate (and density) of drilling fluid through drill string 108, which modulates the rotational speed of rotor 600 in positive displacement motor power section 204; the overall rotational speed of drill string 108. All of these variables can affect the overall oscillating characteristics of the drill string at particular nodal points along drill string 108.
In some examples, placement planning software may be utilized to specify, within a given tolerance such as 60 meters, the correct placement of one or more lateral oscillation tools 200 along a drill string 108. The software may factor in all of the foregoing variables in the context of a particular drilling operation involving a particular drill string having a particular steel grade and burst, stiffness, and connection type, a particular bottom hole assembly (BHA), such as ones having a rotary or positive displacement motor, a particular bit and BHA mass, stabilization tools including on the drill string, the natural frequency of the drill string, environmental factors (temperature, drilling fluid composition, drilling fluid flowrate, hydrogen sulphate (H2S) concentration, under-balanced drilling (UBS) conditions, drill string rotations per minute (RPM), formation characteristics), well design (vertical, inclined, horizontal, or a combination thereof), and dogleg severity.
Placement planning software may assess the entire drilling operation from drilling start to planned terminal depth. Placement planning may include an analysis of net effects of tool placement based on a range of rotational speeds (e.g., 0-350 rpm) while under particular drilling conditions, including without limitation, weight-on-bit, torque, and hydraulic mean specific energy. Variables may also include the local nodal points where the drill string wraps to store energy to pass up and down the drill string and unloads where the inertia is overcome, which is a function of mass and localized wellbore frictional co-efficient).
After placement planning is accomplished, a drilling operation may be conducted wherein one or more lateral oscillation tools 200 are incorporated into the drill string to achieve the desired oscillation characteristics during the drilling operation.
In block 2802, a desired oscillation characteristic for drill string 108 is computed. This computation may take into account many factors relating to the drill string and its operation, including, without limitation, including: the flow rate (and density) of drilling fluid through drill string 108; the overall rotational speed of drill string 108, the composition and material properties of the drill string, including the types of materials; the trajectory of the wellbore, which may include vertical, near-vertical, horizontal, and near-horizontal sections as well as one or more kick-off and other transition points between such sections; the subsurface geologic conditions existing between the surface and the formation to be accessed, and so on. The desired oscillation characteristics for drill string 108 may include identification of oscillational nodal points at one or more locations along the drill string, thereby establishing percussive forces against the borehole wall at desired locations along the drill string.
Next, in block 2804, location(s) for placement of one or more lateral oscillation tools 200 may be computed. This computation may involve selective tuning of the one or more lateral oscillation tools 200 through selective filling of one or more cylindrical tuning channels 1810 in the one or more lateral oscillation tools 200. This computation may also take into account other variables relating to the drilling operation, including, without limitation: the number of lateral oscillation tools 200 to be included in drill string 108; the position of placement of one or more lateral oscillation tools 200 along the length of drill string 108 (taking into account the overall length of the drill string); the selection of which of the cylindrical tuning channels 1810 of each unbalanced mass 1800 to be populated with high-density material to alter the weight balance of the respective unbalanced mass; the orientation of each pair of unbalanced masses 1800 in a given lateral oscillation tool 200 (i.e., either in alignment or ninety-degrees offset, as described herein); the flow rate (and density) of drilling fluid through drill string 108, which modulates the rotational speed of rotor 600 in motor power section 204; and the overall rotational speed of drill string 108.
Next, in block 2806, a drilling operation may be conducted in which the one or more lateral oscillation tools 200 are inserted at the location(s) computed in block 2804 to achieve the desired oscillational characteristics of drill string 108.
The foregoing description, for purposes of explanation, uses specific nomenclature to provide a thorough understanding of the disclosure. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the systems and methods described herein. Various substitutions, modifications, and variations of the examples described herein may be made in a given implementation. For instance, in examples herein a fluid-driven positive displacement motor is utilized for rotation of one or more unbalanced masses 1800. In other examples, and as noted above, a different motor, such as a variable electric turbine powered motor, may be utilized. In such examples, lateral impact forces may be adjusted real-time and through the downhole adaptive learning software.
The foregoing descriptions of specific examples are presented for purposes of illustration and description. Examples herein are not intended to be exhaustive of or to limit this disclosure to the precise forms described. Many modifications and variations are possible in view of the above teachings. The examples are shown and described in order to best explain the principles of this disclosure and practical applications, to thereby enable others skilled in the art to best utilize this disclosure and various examples with various modifications as are suited to the particular use contemplated. It is intended that the scope of this disclosure be defined by the claims and their equivalents below.
Claims
1. A lateral oscillation tool, comprising:
- a motor;
- a rotating mandrel coupled to the motor; and
- a first unbalanced mass coupled to the rotating mandrel to generate lateral oscillation of the lateral oscillation tool.
2. The lateral oscillation tool of claim 1, wherein the rotating mandrel is coupled to the motor by a flex shaft.
3. The lateral oscillation tool of claim 1, wherein the first unbalanced mass comprises a cylindrical body having a first central axis and an inner annulus having a second central axis offset from the first central axis.
4. The lateral oscillation tool of claim 3, wherein:
- the first unbalanced mass has a plurality of tuning channels therein, and
- a high-density material is selectively introduced into one or more of the plurality of tuning channels.
5. The lateral oscillation tool of claim 4, further comprising a second unbalanced mass coupled to the rotating mandrel.
6. The lateral oscillation tool of claim 1, further comprising a flow diverter for diverting a flow of drilling fluid through a central annulus of the mandrel.
7. The lateral oscillation tool of claim 4, wherein the high-density material comprises tungsten.
8. A drill string for operations in a wellbore, the drill string comprising:
- a plurality of assembled pipe sections;
- a bottom hole assembly; and
- at least one lateral oscillation tool disposed between two of the plurality of pipe sections, the lateral oscillation tool including: a motor; a rotating mandrel coupled to the motor; and a first unbalanced mass coupled to the rotating mandrel to generate lateral oscillation of the lateral oscillation tool.
9. The lateral oscillation tool of claim 8, wherein the rotating mandrel is coupled to the motor by a flex shaft.
10. The lateral oscillation tool of claim 8, wherein the first unbalanced mass comprises a cylindrical body having a first central axis and an inner annulus having a second central axis offset from the first central axis.
11. The lateral oscillation tool of claim 10, wherein the first unbalanced mass has a plurality of tuning channels therein, wherein a high-density material is selectively introduced into one or more of the plurality of tuning channels.
12. The lateral oscillation tool of claim 11, further comprising a second unbalanced mass coupled to the rotating mandrel.
13. The lateral oscillation tool of claim 8, further comprising a flow diverter for diverting flow of drilling fluid through a central annulus of the mandrel.
14. The lateral oscillation tool of claim 11, wherein the high-density material comprises tungsten.
15. A method of performing operations in a wellbore, comprising:
- providing a lateral oscillation tool in a drill string, the lateral oscillation tool comprising: a motor; a mandrel coupled to the motor; and a first unbalanced mass coupled to the mandrel to generate lateral oscillation of the lateral oscillation tool; and
- controlling rotation of the motor to cause rotation of the mandrel and the first unbalanced mass, such that lateral oscillation of the drill string is produced.
16. The method of claim 15, further comprising coupling the rotating mandrel to the motor by a flex shaft.
17. The method of claim 16, wherein the first unbalanced mass comprises a cylindrical body having a first central axis and an inner annulus having a second central axis offset from the first central axis.
18. The method of claim 17, further comprising:
- providing a plurality of tuning channels in the first unbalanced mass; and
- selectively introducing a high-density material into one or more of the plurality of tuning channels.
19. The method of claim 15, further comprising a second unbalanced mass coupled to the rotating mandrel.
20. The method of claim 1, further comprising providing a flow diverter for diverting flow of drilling fluid through a central annulus of the mandrel.
Type: Application
Filed: May 19, 2021
Publication Date: Nov 25, 2021
Inventor: Michael Denton Blakely (Spring, TX)
Application Number: 17/325,128