The present invention relates generally to wellbore tubular and, more specifically, to a wear and buckle resistant drill pipe.
Drilling activity in hard and tight Shale formations has increased substantially in the last few years. The wells that are drilled in these formations are generally very deep and complex. They can be comprised of depths that may exceed 10,000 feet vertically and 10,000 feet in the lateral section of the well.
During the drilling operation of these wells, which may include, but are not limited to, tripping in and tripping out of the well, sliding, rotation, etc., the drill pipe is subjected to high compressive loads that could cause severe buckling of the drill pipe. The buckling could manifest itself as Helical Buckling in the vertical section and/or Sinusoidal Buckling in the lateral section. Sinusoidal buckling occurs when the axial force on a long column, in this case drill pipe, exceeds the critical buckling force and the pipe elastically deforms or bends and takes on a snake-like shape in the hole. Weight transfer is still possible during Sinusoidal Buckling, but is inefficient. Additional compressive loads cause Sinusoidal buckling to transition to Helical Buckling, and take on a corkscrew-like shape in the hole. As such, Helical Buckling is more severe and occurs after Sinusoidal buckling.
Helical Buckling may or may not cause plastic or permanent deformation of the pipe, depending upon the amount of axial compressive forces applied, although most buckling stresses are below the yield strength of the pipe. In its most severe form, Helical Bucking can result in Helical Lockup, which is when weight can no longer be transferred to the bit.
The critical buckling load of drill pipe is not only dependent on drilling conditions, such as drill pipe size and hole size, but also and more important is whether the wellbore is straight, horizontal, curving, or inclined. In highangle wells, the force of gravity pulls the drill string against the low side of the hole. This helps to support and constrain the pipe along its length, stabilizing the string and as a result, allowing the drill pipe to withstand higher axial loads before buckling.
Inversely, vertical sections are the most susceptible to buckling. Critical compression in the vertical section of the hole can result in buckling. In build sections, the bending forces exerted by the hole help the pipe to resist buckling. However, pipe will always buckle first in a straight section.
Buckling also causes an increase in drill pipe casing contact and wellbore drill pipe contact. Along with the increased contact, the drill pipe also sees increased side force due to buckling on these contact areas. The more weight applied at surface, the more the coiled pipe presses into the sides of the hole—which has lead many in the industry to support the belief that bucking causes excessive tube wear.
Buckling not only can damage the pipe, it can also negatively affect drilling operations. In slide drilling, for example, buckling may prevent the desired weight on bit because of an increase in drill string side loads to the point that weight cannot be efficiently transmitted to the bit. At the same time, side loads are increased by buckling of the drill pipe due to compressive loading, further exacerbating the problem.
Ultimately, due to the severe drilling environment in downhole wells, the useful life of the drill pipe is severely shortened. In addition to buckling, the drill pipe may exhibit severe abrasion on one side of the tool joint following the failure of the hardbanding, which will lead to wall thickness loss at the tool joint and/or washouts at the middle section of the tubes.
In view of the foregoing, there is a need in the art for a method by which the useful life of the drill pipe is extended against downhole abrasions and buckling, thereby providing a drill pipe having increased wear and buckle resistance.
Exemplary embodiments and methodologies of the present invention provide a drill pipe in which various sections of the pipe between the tool joints are strengthened, or the shape is altered, in order to improve the wear and buckle resistance of the drill pipe. In a first embodiment, at least one portion of the drill pipe undergoes a hardening process that results in that portion being strengthened. The hardening process can be, for example, a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process. In another embodiment, at least one portion of the drill pipe is expanded in order to strengthen that portion of the pipe. The shape of the expanded section can remain circular or be formed into some other sectional profile, such as a modified hexagonal or elliptical shape, which will strengthen the expanded portions of the drill pipe in order to improve erosion resistance and to reduce friction. In the alternative, a sleeve can be applied to the strengthened portion in which a surface enhancer could be applied to the surface of the sleeve or the sleeve surface itself can undergo the hardening process. Furthermore, a pipe can be inserted along the expanded portion and expanded along with the expanded portion, thus providing further strengthening to the drill pipe.
Illustrative embodiments and related methodologies of the present invention are described below as they might be employed in a wear and buckle resistant drill pipe. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in the development of any such actual embodiment, numerous implementation-specific decisions must 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 might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. Further aspects and advantages of the various embodiments and related methodologies of the invention will become apparent from consideration of the following description and drawings.
In this exemplary embodiment, section 12 has been quenched and tempered using an austenitizing temperature of roughly 1700 degrees Fahrenheit and a tempering temperature of roughly 1050 degrees Fahrenheit. However, those ordinarily skilled in the art having the benefit of this disclosure realize other temperatures and/or time periods may be utilized to achieve desired results. Also, the length of middle section 12 is between 5-15 feet in this exemplary embodiment. However, the length may be longer or shorter as would be understood by one ordinarily skilled in the art having the benefit of this disclosure.
Drill pipe 10 also comprises sections 14 located adjacent to section 12 which are not hardened as described above in order to increase the strength of section 12. As a result, the portion of sections 14 adjacent to the tool joints remain at the original lower strength of the steel (or other material) which allows for a more reliable slip engagement. (If the portions of section 14 adjacent to the tool joints were hardened, the possibility of failure due to the slips (not shown) engaging the hardened high strength area would be greatly increased because the hardened area would be more susceptible to cracking). Also in this exemplary embodiment, a surface enhancer, such as hardbanding for example, is applied to sections 14a and 14b using any suitable method as would be readily understood by one ordinarily skilled in the art having the benefit of this disclosure. Furthermore, any suitable hardbanding material such as, but not limited to, tungsten carbides or chromium alloy hardbanding, may be utilized. In addition, a surface enhancer may also be applied to the outer surface of middle section 12. Accordingly, as a result of the described hardening process, middle section 12 of drill pipe 10, which is subjected to abrasion during downhole operations, will resist wear and show less erosion at the area of contact with the cased and open hole.
The yield strength of section 12 will increase to a degree proportional to the amount of expansion, as would be understood by one ordinarily skilled in the art having the benefit of this disclosure. Moreover, profile 18 of section 12 may be expanded in a variety of shapes, such as a circular or pentagon shape, as illustrated in
After section 12 is expanded, it may be hardened as described above in relation to the exemplary embodiment of
Referring to
As can been seen in
Sleeve 20 is then be fastened to middle section 12 using any suitable method such as, for example, shrink fitting, welding, epoxy, etc. Moreover, surface enhancer 16 may be applied to the outer surface of sleeve 20. Here, surface enhancer 16 may be, for example, hardbanding, titanium, carbon fiber, induced hardening material, or some other friction and/or abrasion reducing material or mechanism. In the alternative, sleeve 20 itself may be made of a variety of materials which reduce friction and erosion, such as, for example, titanium or carbon fiber for example. In addition, the outer surface of sleeve 20 may be hardened using one of the hardening processes described herein. Accordingly, through use of sleeve 20, the wear and buckle resistance of drill pipe 10 is greatly enhanced.
An exemplary embodiment of the present invention provides a drill pipe comprising a first joint located on an upper end of the drill pipe; a second joint located on a lower end of the drill pipe; a tubular body extending between the first and second joints, the tubular body comprising: an upper section extending beneath the first joint; a middle section extending beneath the upper section; and a lower section extending beneath the middle section, wherein a portion of the middle section of the tubular body comprises hardened material, while the first and second joints and the upper and lower sections of the drill pipe comprise a softer material, the hardened material being formed as a result of the middle section undergoing a hardening process, thereby resulting in a hardened middle section. In another exemplary embodiment, the hardening process comprises at least one of a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process.
Yet another exemplary embodiment comprises a surface enhancer on an outer surface of the hardened middle section. In another, the surface enhancer is at least one of a friction-reducing material or an abrasion-resistant material. In yet another, a plurality of portions of the upper, middle, and lower sections of the drill pipe also comprise hardened material which is formed through the use of the hardening process.
Another exemplary embodiment of the present invention provides a drill pipe comprising: a first joint located on an upper end of the drill pipe; a second joint located on a lower end of the drill pipe; a tubular body extending between the first and second joints, the tubular body comprising: an upper section extending beneath the first joint; a middle section extending beneath the upper section; and a lower section extending beneath the middle section, wherein the middle section of the tubular body comprises an expanded section in which an inner diameter of the expanded section is larger than an inner diameter of the upper and lower sections of the drill pipe. Another embodiment comprises a surface enhancer on an outer diameter of the expanded section. In yet another, the expanded section comprises at least one of a circular or non-circular shape.
In another embodiment, the expanded section comprises a hardened material which has undergone a hardening process, the hardening process being at least one of a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process. In yet another embodiment, a plurality of portions of the upper, middle, and lower sections of the drill pipe also comprise expanded sections. In another exemplary embodiment, the drill pipe further comprises a sleeve fixed atop an outer surface of the expanded section. In another, the sleeve comprises a surface enhancer on an outer surface of the sleeve. In yet another, the surface enhancer comprises at least one of a friction-reducing or abrasion-resistant material. In another, the outer surface of the sleeve comprises a hardened material which has undergone a hardening process. In yet another, an internal pipe is positioned along the inner diameter of the expanded section, an inner diameter of the internal pipe being substantially flush with the inner diameters of the upper and lower sections of the drill pipe.
An exemplary methodology of the present invention provides a method of manufacturing a drill pipe, the method comprising the steps of: (a) providing a first joint located on an upper end of the drill pipe; (b) providing a second joint located on a lower end of the drill pipe; and (c) providing a tubular body extending between the first and second joints, the tubular body comprising: an upper section extending beneath the first joint; a middle section extending beneath the upper section; and a lower section extending beneath the middle section, wherein a portion of the middle section of the tubular body comprises hardened material, while the first and second joints and the upper and lower sections of the drill pipe comprise a softer material, the hardened material being formed as a result of the middle section undergoing a hardening process, thereby resulting in a hardened middle section. In another, the hardening process comprises at least one of a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process. Yet another methodology further comprises the step of applying a surface enhancer on an outer surface of the hardened middle section.
In another methodology, the surface enhancer is at least one of a friction-reducing material or a abrasion-resistant material. In yet another, the method further comprises the step of applying the hardening process to a plurality of portions of the upper, middle, and lower sections of the drill pipe in order to transform the plurality of portions into hardened material.
Another exemplary methodology of the present invention provides a method of manufacturing a drill pipe, the method comprising the steps of: (a) providing a first joint located on an upper end of the drill pipe; (b) providing a second joint located on a lower end of the drill pipe; and (c) providing a tubular body extending between the first and second joints, the tubular body comprising: an upper section extending beneath the first joint; a middle section extending beneath the upper section; and a lower section extending beneath the middle section, wherein the middle section of the tubular body comprises an expanded section in which an inner diameter of the expanded section is larger than an inner diameter of the upper and lower sections of the drill pipe. In another methodology, the method further comprises the step of providing a surface enhancer on an outer diameter of the expanded section. In yet another, the expanded section comprises at least one of a circular or non-circular shape. In another, the method further comprises the step of applying a hardening process to the expanded section, thereby transforming the expanded section into a hardened material.
In another exemplary method, the hardening process is at least one of a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process. In yet another, the method further comprises the step of expanding a plurality of portions of the upper, middle, and lower sections of the drill pipe. In another, the method further comprises the step of affixing a sleeve atop an outer surface of the expanded section. In yet another, the method further comprises the step of applying a surface enhancer on an outer surface of the sleeve. In another, the surface enhancer comprises at least one of a friction-reducing or abrasion-resistant material. In yet another, the method further comprises the step of applying the hardening process to the outer surface of the sleeve, thereby resulting in a hardened sleeve. In another, the method further comprises the steps of: providing an internal pipe positioned along the inner diameter of the expanded section; and expanding the internal pipe adjacent the expanded section, wherein an inner diameter of the internal pipe is substantially flush with the inner diameters of the upper and lower sections of the drill pipe.
Another exemplary methodology of the present invention provides a method of manufacturing a drill pipe, the method comprising the steps of: (a) providing a first joint located on an upper end of the drill pipe; (b) providing a second joint located on a lower end of the drill pipe; (c) providing a tubular body extending between the first and second joints, the tubular being made of a material having a predetermined hardness; and (d) applying a hardening process to at least one portion of the tubular body, thereby resulting in a material which is harder than the material having the predetermined hardness. In another methodology, the method further comprises the step of applying a sleeve atop the at least one portion of the tubular body. In another, the method further comprises the step of: applying a surface enhancer to an outer surface of the at least one portion of the tubular body; or applying the surface enhancer to an outer surface of a sleeve which has been affixed atop the at least one portion of the tubular body. In another, the method further comprises the step of applying the hardening process to the sleeve.
Another exemplary methodology of the present invention provides a method of manufacturing a drill pipe, the method comprising the steps of: (a) providing a first joint located on an upper end of the drill pipe; (b) providing a second joint located on a lower end of the drill pipe, a tubular body extending between the first and second joints; and (c) expanding at least one portion of the tubular body. In another, the method further comprises the step of performing a hardening process on the expanded portion of the tubular body. In another, the hardening process is at least one of a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process. In yet another, the method further comprises the step of affixing a sleeve atop the at least one expanded portion.
In another, the method further comprises the step of applying a surface enhancer on an outer surface of the sleeve. In another, the method further comprises the step of performing a hardening process on the sleeve, thereby resulting in a hardened sleeve. In yet another, the method further comprises the step of providing an internal pipe positioned along an inner diameter of the at least one expanded portion, the internal pipe being expanded along with the at least one expanded portion such that an inner diameter of the drill pipe is substantially uniform throughout the drill pipe.
Another exemplary methodology of the present invention provides a method of using a drill pipe, the method comprising the steps of: (a) deploying the drill pipe down hole, the drill pipe comprising: a first joint located on an upper end of the drill pipe; a second joint located on a lower end of the drill pipe; a tubular body extending between the first and second joints, the tubular body comprising: an upper section extending beneath the first joint; a middle section extending beneath the upper section; and a lower section extending beneath the middle section, wherein a portion of the middle section of the tubular body comprises hardened material, while the first and second joints and the upper and lower sections of the drill pipe comprise a softer material, the hardened material being formed as a result of the middle section undergoing a hardening process, thereby resulting in a hardened middle section; and (b) performing a drilling operation utilizing the drill pipe. In another, the hardening process comprises at least one of a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process.
Another exemplary methodology of the present invention provides a method of using a drill pipe, the method comprising the steps of: (a) deploying the drill pipe down hole, the drill pipe comprising: a first joint located on an upper end of the drill pipe; a second joint located on a lower end of the drill pipe; a tubular body extending between the first and second joints, the tubular body comprising: an upper section extending beneath the first joint; a middle section extending beneath the upper section; and a lower section extending beneath the middle section, wherein the middle section of the tubular body comprises an expanded section in which an inner diameter of the expanded section is larger than an inner diameter of the upper and lower sections of the drill pipe; and (b) performing a drilling operation utilizing the drill pipe. In another, the drill pipe further comprises a sleeve surrounding the expanded section. In yet another, the expanded section has been hardened using a hardening process comprising at least one of a heat treatment, carburizing, nitriding, carbonitriding, flame hardening or chromizing process.
Although various embodiments and methodologies have been shown and described, the invention is not limited to such embodiments and methodologies and will be understood to include all modifications and variations as would be apparent to one skilled in the art. For example, downhole requirements may not necessitate use of a hardening process, expansion, and sleeve application in a single drill pipe. Rather, one or more methods may be utilized for any given section of drill pipe 10. Also, it may not be necessary, or desired, to apply surface enhancement 16 to sleeve 20. Additionally, a sleeve could be applied to a drill pipe without performing any hardening process on the tubular. Moreover, the buckle and wear resistant technology described herein may be applied to tubulars and downhole tools other than drill pipe as would be understood by one ordinarily skilled in the art having the benefit of this disclosure. Therefore, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the intention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the appended claims.
Number | Name | Date | Kind |
---|---|---|---|
2259023 | Clark | Oct 1941 | A |
2295873 | Stone | Sep 1942 | A |
2330933 | Terrell, Jr. | Oct 1943 | A |
3067593 | McCool | Dec 1962 | A |
3080179 | Huntsinger | Mar 1963 | A |
3682256 | Stuart | Aug 1972 | A |
3773359 | Chance et al. | Nov 1973 | A |
3784238 | Chance et al. | Jan 1974 | A |
4416476 | Garrett | Nov 1983 | A |
4460202 | Chance et al. | Jul 1984 | A |
4987961 | McNeely, Jr. | Jan 1991 | A |
5148876 | Wilson | Sep 1992 | A |
5165491 | Wilson | Nov 1992 | A |
5332049 | Tew | Jul 1994 | A |
5713423 | Martin et al. | Feb 1998 | A |
5853199 | Wilson | Dec 1998 | A |
6012744 | Wilson et al. | Jan 2000 | A |
6352107 | Bennett et al. | Mar 2002 | B1 |
6457532 | Simpson | Oct 2002 | B1 |
6758499 | Belew et al. | Jul 2004 | B1 |
7040422 | Springer | May 2006 | B2 |
7182160 | Boulet | Feb 2007 | B2 |
7487840 | Gammage et al. | Feb 2009 | B2 |
7810573 | Baird | Oct 2010 | B2 |
7814996 | Indrupskiy et al. | Oct 2010 | B2 |
8286715 | Bailey et al. | Oct 2012 | B2 |
8561707 | Jin et al. | Oct 2013 | B2 |
20020185188 | Quigley et al. | Dec 2002 | A1 |
20080035328 | Hill et al. | Feb 2008 | A1 |
20090223200 | Kinert et al. | Sep 2009 | A1 |
20090321144 | Wyble et al. | Dec 2009 | A1 |
20100038404 | Lingnau et al. | Feb 2010 | A1 |
20100044110 | Bangru et al. | Feb 2010 | A1 |
20100230167 | Nichols et al. | Sep 2010 | A1 |
20120306199 | David | Dec 2012 | A1 |
20130056225 | Pabon et al. | Mar 2013 | A1 |
20130112481 | Wang | May 2013 | A1 |
Entry |
---|
RDT, “Wear Knot Drill Pipe Features and Benefits”, www.rdt-usa.com. |
RDT, “Wear Knot Drill Pipe Technical Description”, www.rdt-usa.com. |
WearSox, “Twin Wire ARC Thermal Spray Process”, www.wearsox.com. |
Attachment B: Sinusoidal Buckling and Countermeasures, “Special Downhole Tools to Improve Drillpipe Stiffness”, K&M Technology Group, Drilling Design and Implementation for Extended Reach and Complex Wells, 3rd Edition, 2003, p. 126-131. |
Canadian Office Action for Canadian Patent Applicaton No. 2791599, dated Jul. 3, 2014. |
Number | Date | Country | |
---|---|---|---|
20130098687 A1 | Apr 2013 | US |