Patent Application
20160201416
1. Field of the Invention
The present disclosure relates generally to the recovery of subterranean deposits and more specifically to methods and systems for milling materials in a well.
2. Description of Related Art
Wells are drilled at various depths to access and produce oil, gas, minerals, and other naturally-occurring deposits from subterranean geological formations. Hydrocarbons may be produced through a wellbore traversing the subterranean formations. The wellbore may be relatively complex and include, for example, one or more lateral branches extending at an angle from a parent or main wellbore. Forming lateral wellbores typically involves first creating a window in a casing or other metal tubing lining the main wellbore. A window mill or other milling tool may be used initiate and form the window. After the window is created, a drill bit may be passed through the window to form the lateral wellbore.
In additional to milling windows for lateral wellbore formation, milling tools may be used for many other downhole tasks, some of which include downhole cleaning functions, removal of plugs, debris removal, casing restoration, and other functions. Milling tools typically are used to cut through metallic objects or other materials that have been delivered into the wellbore. While milling tools may include hardened cutters or inserts to improve cutting performance and wear resistance, the hardened cutters often break free from the milling tools during use thereby causing quicker wear of the tool.
The following figures are included to illustrate certain aspects of the present disclosure, and should not be viewed as exclusive embodiments. The subject matter disclosed is capable of considerable modifications, alterations, combinations, and equivalents in form and function, without departing from the scope of this disclosure.
In the following detailed description of the illustrative embodiments, reference is made to the accompanying drawings that form a part hereof These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is understood that other embodiments may be utilized and that logical structural, mechanical, electrical, and chemical changes may be made without departing from the spirit or scope of the invention. To avoid detail not necessary to enable those skilled in the art to practice the embodiments described herein, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the illustrative embodiments is defined only by the appended claims.
The embodiments described herein relate to systems, tools, and methods for milling materials in a well, particularly metallic and non-geological materials. While milling tools are sometimes used to remove a small amount of geological material following milling of metallic and other materials, milling tools, unlike drill bits, are not designed principally to remove rock and other geological material. Embodiments of milling tools described herein include blades having a cladding material coupled to the blades, and it is these blades that are responsible for cutting metallic materials in the well. The cladding material may be coupled to the blades in various ways, but the cladding material may form a metallurgical bond with the blades. In addition to the cladding material, cutting inserts may be coupled to the cladding material, and may extend beyond an outer surface of the cladding material. By securing the cutting inserts with the cladding material, improved wear resistance and longevity of the milling tools may be achieved. The cladding material, through metallurgical bonds to the cutting inserts and blades, is able to more securely retain the cutting inserts than traditional brazing material. Furthermore, the process of applying the cladding material to the blades and cutting inserts may include methods that do not require as much heat as brazing, thereby protecting the base material of the blade itself from heat-induced weakening.
Unless otherwise specified, any use of any form of the terms “connect,” “engage,” “couple,” “attach,” or any other term describing an interaction between elements is not meant to limit the interaction to direct interaction between the elements and may also include indirect interaction between the elements described. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to”. Unless otherwise indicated, as used throughout this document, “or” does not require mutual exclusivity.
Referring to
The downhole milling tool 110 further includes a plurality of blades 130 extending radially outward from the body 114. Each blade 130 extends along a length of the body and is oriented substantially parallel to a longitudinal axis 134 of the body 114. In the embodiment illustrated in
The downhole milling tool 110 further includes a cladding material 142 coupled to one or more of the blades 130, and in some embodiments, the cladding material 142 is coupled to each of the blades 130. The cladding material 142 may be any material that has a higher hardness than the material from which the blade 130 is formed. In some embodiments, the hardness of the cladding material may be greater than or equal to approximately 60 HRC. The hardness of the cladding material 142 and thus the wear resistance of the blade 130 may be supplemented by including a plurality of cutting inserts 150 coupled to the cladding material 142. The cutting inserts 150 may be at least partially embedded within the cladding material 142 such that the bond between the cladding material 142 and the cutting inserts 150 and between the cladding material 142 and the blade 130 secures the cutting inserts 150 to the blade 130. It should be noted that while some of the cutting inserts 150 may contact the blade 130, no bond necessarily exists between the cutting insets 150 and the blade 130. When cutting inserts 150 are coupled to the cladding material 142, a high-hardness iron-based cladding may be used, such as Apollo-Clad 1403 Powder supplied by Apollo-Clad. As explained in more detail below, powder-based cladding materials may be applied to a blade by using a laser to melt the powder and create the necessary bond between the cladding material and the blade or cutting inserts. Cladding materials such as the Apollo-Clad 1403 Powder have a hardness of approximately 60-65 HRC.
In some embodiments, as an alternative to the use of cutting inserts 150, the cladding material 142 alone may be coupled to the blade 130 and used to provide the increased cutting performance and wear resistance that is desired. In such an embodiment, it is desired that the cladding material 142 have an even higher hardness than materials used in conjunction with the cutting inserts 150. In some embodiments, it is desired that the hardness of such a material be greater than or equal to approximately 60 HRC. An example of a cladding material that may be coupled to the blade 130 and used alone without cutting inserts 150 is a material that includes approximately 62 weight percent Tungsten Carbide, approximately 30 weight percent Nickel, and approximately 6 weight percent Chromium. A suitable material may be WC200 supplied by Kennametal Conforma Clad of New Albany, Ind. The hardness of this material is approximately 64-70 HRC.
In some embodiments the coupling between the cladding material 142 and the blades 130 forms a metallurgical bond. Traditional milling tools may employ hardened inserts to increase wear resistance, but these inserts are brazed to the blades of the milling tool. The brazing matrix that holds the inserts does not have high hardness properties, and since the bonds between the brazing matrix and inserts are only mechanical, as opposed to metallurgical, the inserts are easily released by the brazing matrix during use of the milling tool. In contrast, the metallurgical bonds between the cladding material 142 and blades 130 (and in some embodiments, between the cladding material 142 and cutting inserts 150), provides much more resistance to wear and removal from the blades. Generally accepted brazing strength is approximately 25,000 psi whereas the strength of a metallurgical bond such as that provided by a cladding material may be 70,000 psi, thereby yielding two to three times the bond strength. The increased hardness of the cladding material 142 relative to brazing matrix also increases wear resistance, and in some embodiments, allows the cladding material 142 to be used without cutting inserts 150.
The application of the cladding material 142 to the blades 130 also typically involves less heat than brazing activities. The addition of brazing matrix and hardened inserts may alter heat the blades to such a temperature that the strength or ductility of the blades is compromised, thereby requiring additional heat treatment steps to ensure suitable working life. In contrast, the addition of the cladding material 142 to the blades does not heat the blades 130 to a level that degrades the strength or ductility of the blades 130.
Coupling of the cladding material 142 to the blades 130 (and to the cutting inserts 150 in certain embodiments) may be performed by various processes, including roll welding, explosive welding, and laser cladding. In laser cladding, the cladding material 142 is delivered to a nozzle in powder form. The powder-based cladding material 142 is carried by an inert gas to the blade 130, where a laser beam is defocused on a particular spot to form a melt pool. Either the laser optics and powder nozzle are moved (or the blade is moved) as tracks of cladding material 142 are added to the blade 130.
Referring to
The downhole milling tool 210 further includes a plurality of blades 230 extending radially outward from the body 214. Each blade 230 extends along a portion of a length of the body and is arranged in a spiral or helical configuration on the body 214 relative to a longitudinal axis 234 of the body 214. In the embodiment illustrated in
The downhole milling tool 210 further includes a cladding material 242 coupled to one or more of the blades 230, and in some embodiments, the cladding material 242 is coupled to each of the blades 230. The cladding material 242 may be any material that has a higher hardness than the material from which the blade 230 is formed. In some embodiments, the hardness of the cladding material may be greater than or equal to approximately 60 HRC. The hardness of the cladding material 242 and thus the wear resistance of the blade 230 may be supplemented by including a plurality of cutting inserts 250 coupled to the cladding material 242. The cutting inserts 250 may be at least partially embedded within the cladding material 242 such that the bond between the cladding material 242 and the cutting inserts 250 and between the cladding material 242 and the blade 230 secures the cutting inserts 250 to the blade 230. It should be noted that while some of the cutting inserts 250 may contact the blade 230, no bond necessarily exists between the cutting insets 250 and the blade 230. When cutting inserts 250 are coupled to the cladding material 242, a high-hardness iron-based cladding may be used, such as Apollo-Clad 1403 Powder supplied by Apollo-Clad. As explained in more detail below, powder-based cladding materials may be applied to a blade by using a laser to melt the powder and create the necessary bond between the cladding material and the blade or cutting inserts.
Cladding materials such as the Apollo-Clad 1403 Powder have a hardness of approximately 60-65 HRC.
In some embodiments, as an alternative to the use of cutting inserts 250, the cladding material 242 alone may be coupled to the blade 230 and used to provide the increased cutting performance and wear resistance that is desired. In such an embodiment, it is desired that the cladding material 242 have an even higher hardness than materials used in conjunction with the cutting inserts 250. In some embodiments, it is desired that the hardness of such a material be greater than or equal to about 70 HRC. An example of a cladding material that may be coupled to the blade 230 and used alone without cutting inserts 250 is a material that includes approximately 62 weight percent Tungsten Carbide, approximately 30 weight percent Nickel, and approximately 6 weight percent Chromium. A suitable material may be WC200 supplied by Kennametal Conforma Clad of New Albany, Ind. The hardness of this material is approximately 64-70 HRC.
Like the milling tool 110 illustrated in
Referring to
The downhole milling tool 310 further includes a plurality of blades 330 extending radially outward from the body 314. Each blade 330 extends along a portion of a length of the body and is arranged in a spiral or helical configuration on the body 314 relative to a longitudinal axis 334 of the body 314. In the embodiment illustrated in
The downhole milling tool 310 further includes a cladding material 342 coupled to one or more of the blades 330, and in some embodiments, the cladding material 342 is coupled to each of the blades 330. The cladding material 342 may be any material that has a higher hardness than the material from which the blade 330 is formed. In some embodiments, the hardness of the cladding material may be greater than or equal to approximately 60 HRC.
The hardness of the cladding material 342 and thus the wear resistance of the blade 330 may be supplemented by including a plurality of cutting inserts 350 coupled to the cladding material 342. The cutting inserts 350 may be at least partially embedded within the cladding material 342 such that the bond between the cladding material 342 and the cutting inserts 350 and between the cladding material 342 and the blade 330 secures the cutting inserts 350 to the blade 330. It should be noted that while some of the cutting inserts 350 may contact the blade 330, no bond necessarily exists between the cutting insets 350 and the blade 330. When cutting inserts 350 are coupled to the cladding material 342, a high-hardness iron-based cladding may be used, such as Apollo-Clad 1403 Powder supplied by Apollo-Clad. As explained in more detail below, powder-based cladding materials may be applied to a blade by using a laser to melt the powder and create the necessary bond between the cladding material and the blade or cutting inserts. Cladding materials such as the Apollo-Clad 1403 Powder have a hardness of approximately 60-65 HRC.
In some embodiments, as an alternative to the use of cutting inserts 350, the cladding material 342 alone may be coupled to the blade 330 and used to provide the increased cutting performance and wear resistance that is desired. In such an embodiment, it is desired that the cladding material 342 have an even higher hardness than materials used in conjunction with the cutting inserts 350. In some embodiments, it is desired that the hardness of such a material be greater than or equal to about 70 HRC. An example of a cladding material that may be coupled to the blade 330 and used alone without cutting inserts 350 is a material that includes approximately 62 weight percent Tungsten Carbide, approximately 30 weight percent Nickel, and approximately 6 weight percent Chromium. A suitable material may be WC200 supplied by Kennametal Conforma Clad of New Albany, Ind. The hardness of this material is approximately 64-70 HRC.
Like the milling tools 110, 210 illustrated in
Referring to
In
Referring to
A plurality of cutting inserts 550 are coupled to the cladding material 542. The cutting inserts 550 may be arranged in a substantially uniform pattern and may be spaced apart a distance, x. In some embodiments, the cutting inserts may be arranged such that each cutting insert 550 contacts or abuts adjacent cutting inserts. In other embodiments, a more random spacing of the cutting inserts 550 may be employed. In
Referring to
The cutting insert 550 may be formed from a material including approximately 71% tungsten carbide, 13% cobalt, 4% titanium carbide, and 12% tantalum carbide. Properties of the material may include a hardness of approximately 90.4 HRC. In some embodiments, a representative cutting insert may be ICBI270T supplied by Ibex Welding Technologies.
Referring to
A plurality of cutting inserts 650 are coupled to the cladding material 642. The cutting inserts 650 may include crushed carbide elements that are size-screened to ensure that each crushed carbide element is an appropriate size. For example, the screening process may select for use cutting inserts 650 that are between a first volume and a second volume in size. Alternatively, screening may be performed to select cutting inserts 650 that meet particular dimensional measurements. For example, the screening process may use a mesh size that allows 3/16 inch to ¼ inch crushed carbide elements to be selected for use. The crushed carbide elements may be arranged randomly such that some of the crushed carbide elements contact the blade 630 and some do not. Similarly, while many of the crushed carbide elements, may protrude from the cladding material 642, some may be covered by the cladding material 642. The cladding material 642, while of non-uniform thickness in
Milling metal objects and other materials deposited in a wellbore may be key to forming additional lateral wellbores or to cleaning or re-sizing dowhole conduits in the wellbore. The present disclosure describes tools, systems, and methods for milling materials and improving the wear resistance of milling tools. In addition to the embodiments described above, many examples of specific combinations are within the scope of the disclosure, some of which are detailed below.
Example 1. A downhole milling tool comprising:
Example 2. The downhole milling tool of example 2, wherein the cladding material has a hardness of approximately 60 HRC.
Example 3. The downhole milling tool of example 1, wherein the coupling between the cladding material and the at least one of the mill blades includes a metallurgical bond.
Example 4. The downhole milling tool of example 1 further comprising:
Example 5. The downhole milling tool of example 4, wherein the coupling between the plurality of cutting inserts and the cladding material includes a metallurgical bond.
Example 6. The downhole milling tool of example 1, wherein a hardness of the cutting inserts is greater than a hardness of the cladding material.
Example 7. The downhole milling tool of example 1, wherein the cutting inserts have a hardness of approximately 60 HRC.
Example 8. The downhole milling tool of example 1 further comprising: a plurality of cutting inserts coupled to the cladding material;
Example 9. The downhole milling tool of example 1 further comprising:
Example 10. The downhole milling tool of example 1 further comprising:
Example 11. The downhole milling tool of example 1 further comprising:
Example 12. The downhole milling tool of example 1 further comprising:
Example 13. A downhole milling tool for cutting non-geological materials in a well, the downhole milling tool comprising:
Example 14. The downhole milling tool of example 13, wherein the cladding material is deposited on each of the plurality of blades in a substantially uniform thickness.
Example 15. The downhole milling tool of example 13 further comprising:
Example 16. The downhole milling tool of example 13 further comprising:
Example 17. The downhole milling tool of example 1, wherein the downhole milling tool is one of a window mill, a watermelon mill, and a lead mill.
Example 18. A method of improving the wear resistance of downhole milling tool, the method comprising:
Example 19. The method of example 18 further comprising:
Example 20. The method of example 1, wherein the coupling the cladding material to the blade and coupling the cutting inserts to the cladding material further comprises:
It should be apparent from the foregoing that an invention having significant advantages has been provided. While the invention is shown in only a few of its forms, it is not limited to only these embodiments but is susceptible to various changes and modifications without departing from the spirit thereof.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2013/062694 | 9/30/2013 | WO | 00 |
