TUBING JOINT AND USES THEREOF

Abstract

There is provided a tubing joint for use in breaking up scale and debris in fluids circulating within an oil, gas, water or other well to prevent clogging. The tubing joint has a tubular that defines a bore through which fluids flow, and a projection coupled to the tubular and extending into the bore. In some cases, the projection comprises a plurality of projections. The projection forms a partial obstruction within the bore of the tubing joint, against which scale and debris impact as they are carried by the fluid through the bore. Generally, the scale and debris break apart into smaller pieces upon impact, preventing the scale and debris from building up and causing a clog within the oil, gas water or other well.

Description

CROSS-REFERENCE

This patent application claims priority from and the benefit of Canadian Patent Application No. CA 3,060,488, filed Oct. 29, 2019 and incorporates the same by reference.

FIELD

The present disclosure relates generally to well equipment for boreholes. More particularly, the present disclosure relates to a tubing joint adapted to engage and break apart debris and uses thereof.

BACKGROUND

Wells, such as, for example, oil and/or gas wells in the oil and gas industry can become clogged by scale and other debris. Scale can be caused by a deposition of, for example, various salts, oxides, silicates, and/or phosphates onto surfaces within a well, such as an oil well, a gas well, a water well, etc. Some specific, non-limiting examples of scale include metal salts and oxides, such as calcium carbonate, calcium sulfate, barium sulfate, strontium sulfate, iron sulfide, iron oxides, etc.

Wells with considerable hard scale and debris are particularly susceptible to clogging during clean out operations. When well bore clean out operations are conducted using reverse circulation, drilling fluids are reverse circulated down an annular space between a clean out string and the well casing, with the fluid and any debris returning to the surface through the “bore” of the clean out string. On occasion, debris and scale can bridge off and clog tubulars of the clean out string. Clogging of tubulars is more common when the debris contains large pieces.

There remains a need for equipment that prevents or reduces risk of clogging during a clean out operation of operation of an oil and/or gas or other types of well.

SUMMARY

Herein described is a tubing joint that can be used to break up pieces of scale and debris carried by fluids circulating within tubing of a well, such as an oil well, gas well, or water well, thereby reducing the risk of the well clogging. The tubing joint comprises a tubular for circulating a fluid, the tubular defining a bore through which the fluid flows, and a projection coupled to the tubular and extending into the bore. In some examples, the projection comprises a plurality of projections. As it extends into the bore of the tubing joint, the projection forms a partial obstruction that engages and breaks apart scale and debris as it is carried by the fluid through the bore.

Generally, as a well is subject to reverse circulation of fluid, at least a portion of the scale and/or debris in the wellbore flows into the bore of the tubing joint and at least some of the scale and/or debris breaks apart to at least some degree due to impacting the projection(s), and the scale and/or debris are at least partially removed from the wellbore by the reverse circulation of fluids up the clean-out string to surface. In an embodiment disclosed, the scale and/or debris substantially breaks apart and is substantially removed from the wellbore.

In a first aspect, the present disclosure provides a tubing joint, including a downhole tubular, defining a bore therethrough, and a projection coupled to the tubular and extending into the bore, the projection forming a partial obstruction of the bore, adapted to engage and break apart debris in a fluid flowing through the bore.

In an embodiment disclosed the projection extends radially into the bore.

In an embodiment disclosed the projection comprises a plurality of projections.

In an embodiment disclosed each of the plurality of projections is circumferentially displaced relative to each other.

In an embodiment disclosed each of the plurality of projections is longitudinally displaced relative to each other.

In an embodiment disclosed each of the plurality of projections is circumferentially and longitudinally displaced relative to each other to spiral within the bore.

In an embodiment disclosed the projection extends into the bore between about 10 percent and about 30 percent of the diameter of the bore.

In an embodiment disclosed the projection extends into the bore between about 15 percent and about 25 percent of the diameter of the bore.

In an embodiment disclosed the projection extends into the bore about 20 percent of the diameter of the bore.

In an embodiment disclosed the projection is substantially frustoconical shaped.

In an embodiment disclosed the projection is substantially cone shaped.

In an embodiment disclosed the projection is substantially wedge tipped.

In an embodiment disclosed the projection is substantially nub shaped.

In an embodiment disclosed the projection is composed of tungsten carbide, carbon steel, stainless steel, hardened metal or combinations thereof.

In an embodiment disclosed the projection is welded to the tubular.

In an embodiment disclosed the projection is integral with the tubular.

In an embodiment disclosed the tubular is a joint of tubing.

In an embodiment disclosed the tubular has a pin fitting at a first end and a bell fitting at a second end.

In a further aspect, the present disclosure provide use of the tubing joint disclosed herein in a clean out string to remove debris from a wellbore.

In an embodiment disclosed the tubing joint is used to break up debris in a fluid in a well.

In an embodiment disclosed the debris comprises hard scale.

In a further aspect, the present disclosure provides a method for servicing a well having a defined wellbore containing debris, the method including inserting a clean-out string into the wellbore, the clean-out string including a tubing joint as disclosed herein, and reverse circulating a fluid through the well, and rotating the tubing joint to engage the debris with the projection within the bore, wherein at least a portion of the debris is thereby broken apart into broken debris.

In an embodiment disclosed the method includes carrying the broken debris out of the well with the fluid.

In an embodiment disclosed, inserting the clean-out string into the wellbore includes positioning the tubing joint within the wellbore proximate the debris.

In an embodiment disclosed, inserting the clean out string into the wellbore comprises positioning the tubing joint within the wellbore along a bottom portion of the wellbore.

In an embodiment disclosed the fluid is a drilling fluid or a well servicing fluid. In an embodiment, the drilling fluid or the well servicing fluid may be water.

In an embodiment disclosed the well is an oil well, a gas well, an oil and gas well, or a water well.

In an embodiment disclosed the debris includes hard scale or well-bottom debris or both.

BRIEF DESCRIPTION OF THE FIGURES

Embodiments of the present disclosure will now be described, by way of example only, with reference to the attached Figures.

FIG. 1 depicts a partial cross-sectional, side-elevation view of a tubing joint (100) in accordance with an embodiment of the present disclosure, showing a face view (4) and back view (5) of a plurality of projections coupled to a tubular and extending into the bore thereof.

FIG. 2 depicts (A) a perspective view of a tubing joint in accordance with an embodiment of the present disclosure, showing backside welds coupling a plurality of projections to a tubular; and (B) a cross-sectional view of the tubing joint of (A), showing the plurality of projections welded to the tubular and extending into the bore of the tubular.

FIG. 3 depicts a perspective view of a tubing joint in accordance with an embodiment of the present disclosure in use in a wellbore.

DETAILED DESCRIPTION

A tubing joint as described herein may be used to break up scale and debris in a fluid circulating within a well, within a defined wellbore, including but not limited to cased wellbores, uncased wellbores, and combinations thereof including but not limited to wellbores with barefoot completions, the wellbore being a wellbore of, for example, a hydrocarbon recovery well (e.g. producing one or more of oil, gas and water), a water well, an injection well, or a waste disposal well, thereby reducing the risk of the well clogging. Generally, clean out fluid is circulated down an annulus between the joints or length of a cleanout string and the well bore wall, the tubular defining a bore through which the returning fluid flows to the surface; and a projection coupled to the tubular and extending into the bore. The projection(s) form a partial obstruction of the bore to engage and break apart scale and debris as it is carried through the tubing joint by the fluid flowing through the bore. Typically the scale and debris break apart upon impact with the projection(s). Rotation of the cleanout string (and thus the tubing joint) during the operation, greatly increases the effectiveness of the operation due to the kinetic impact of debris chunks with the projection(s). In an example, the projection comprises a plurality of projections.

FIG. 1 shows a tubing joint 100 having a tubular 1, the tubular 1 is a joint of tubing defining a bore 2, and having a bell and pin fitting 7, 8 at either end. A coupling 7 couples the tubular 1 to another tubular. The tubing joint 100 has a projection 3 coupled to the tubular 1 and extending radially into the bore 2. The projection 3 comprises a plurality of projections, each of the plurality of projections being circumferentially and longitudinally displaced relative to each other to spiral within the bore 2. In other examples, each of the plurality of projections is longitudinally displaced relative to each other, and oriented in a spiral throughout a body of the tubular 1. In some installations, the projections may be oriented in a “spiral” shape throughout the body of tubular 1.

FIG. 2 shows the tubing joint 100 with the projection 3 extending radially into the bore 2 and comprising a plurality of projections. The projection 3 is coupled to the tubular 1 by a backside weld 9, and is substantially cone-shaped. As best seen in an end-view of FIG. 2, the projection 3 extends into the bore 2 of the tubular 1. The extension into the bore is preferably between about 10 percent and about 30 percent of the diameter of the bore 2, more preferably between about 15 percent and about 25 percent of the diameter of the bore 2, and more preferably about 20 percent of the diameter of the bore 2. For example, if the bore 2 is 100 mm, then the extension into the bore 2 is preferably between about 10 mm and about 30 mm, preferably between about 15 mm and about 25 mm, and more preferably about 20 mm. Each of the plurality of projections 3 is circumferentially and longitudinally displaced relative to each other to spiral within the bore 2. In some applications, the projections are oriented in a “spiral” shape. The projection into the bore 2 varies, depending on the service conditions and the nature of the debris. In some examples, the projection(s) 3 are substantially frustoconical-shaped or substantially wedge-tipped. In some examples, the projection(s) 3 are composed of tungsten carbide or a hardened metal or a combination thereof. The hardened metal may be, for example, carbon steel or stainless steel. In some examples, the projection(s) 3 are integral with the tubular 1. The projection(s) 3 need not be of uniform lengths throughout the tool and may vary. In a preferred embodiment, the projection(s) 3 are relatively uninform to maintain rotational balance of the tubing joint 100 to reduce vibration in operation. In an embodiment disclosed, the tubing joint 100 is rotationally balanced, for example by design and/or addition of weights and/or removal of material from the tubing joint 100.

Referring to FIG. 3, tubing joint 100 is attached to tubing string or clean-out string 25 and inserted into a wellbore 30 until proximate, at, or beyond debris 40. Debris 40 may be loose within the wellbore 30 and/or at the bottom of the wellbore, freed by contact with the tubing joint 100 and/or the string 25 and/or another clean-out tool (not shown), or freed by reverse circulation or circulation of the fluid 50. At least a portion of the debris 40 is broken up, and preferably the debris 40 is broken up to provide broken debris 60. In an embodiment disclosed, for example, broken debris 60 is sufficiently reduced in size to readily flow up the bore of the clean-out string 25. Reverse circulation of fluid 50 sweeps or otherwise conveys the broken debris 60 and/or debris 40 into the tubing string or clean out string and to the surface. While FIG. 3 illustrates the wellbore 30 as being a substantially vertical portion, the invention may also be applied to wells having slanted, horizontal, lateral, angled, dogleg, and/or radiused sections. The tool can be deployed in any orientation, provided the longitudinal axis of the tool is aligned with the longitudinal axis of the well. While FIG. 3 illustrates the wellbore 30 as having a casing 70, as described herein, the invention may also be applied to uncased wellbores. In an embodiment disclosed, an inlet section 75, below the tubing joint 100, may be provided to accelerate or increase the velocity of the fluid 50 and therefore the debris 40 flowing inside the clean-out string 25 towards the projections 3.

In an example, as generally depicted in FIG. 3, in use the tubing joint 100 may form part of a tubular string, such as a completion or workover string, referred here generally as a clean-out string 25 that is being used to service a well in a formation 35, such as an oil well, gas well, or water well, that has an amount of scale or debris and may be at risk to become clogged; for example, as part of conventional service rig clean out operations. Particularly, the tubing joint 100 may form part of a completion or workover string or clean-out string 25 at a point close to the bottom of the well, and may rotate with the string 25. The tubing joint 100, for example, may be used in a well clean-out operation. Typically during such a clean-out operation, fluid(s), such as a drilling fluid or well-servicing fluid, or water is reverse circulated down an annulus formed between a wellbore of the well and the completion string, with the fluid returning up the completion string bore (indicated by arrows in FIG. 3). When the tubing joint 100 forms part of the clean-out string, at least some of the scale or debris being carried by the drilling fluid up the clean-out string 25 will impact or otherwise contact the projection 3 extending into the bore 2. As illustrated in FIG. 3, a plurality of projections 3 may be coupled to the tubular 1. By impacting the projection 3, the scale or debris may be broken into smaller pieces, thus inhibiting their tendency to bridge off and clog tubulars of the completion string.

In another example, in use the tubing joint 100 is added to a conventional well clean-out string, and is used to assist with breaking up large pieces of scale and other well-bottom debris that, during a clean out operation, are reverse circulated out of the well. As used herein, a clean-out string is a string of tubulars, for example tubing (e.g., coiled tubing or jointed tubing), assembled to clean out a well (e.g., an oil well, gas well, water well) that has its performance restricted or otherwise reduced by well-bottom debris. The clean-out string is generally set up by a service rig attending the wellsite. For example, if in use, a production tubing string is first removed from the affected well and set aside in a suitable manner. Tubing joint 100 is added to the clean-out string as close as possible to the bottom of the string, and is torqued up to a make-up torque suitable for the threads of the clean-out string. In an example, the tubing joint 100 is used in conjunction with some form of clean-out bit that is suitable for use during, for example, at least reverse circulation. The clean-out string is then inserted into, for example, the casing 70 of the affected well and lowered to the point of debris obstruction. Standard industry well servicing practices may be followed during the insertion of the clean-out string. Once the clean-out string is located at the point of debris obstruction, the clean-out string is rotated, and the well is reverse circulated with well-servicing fluid being pumped down to the well-bottom through the annulus between the string and the casing. The well-servicing fluid returns to the surface through the center bore of the clean-out string, including through the bore 2 of the tubing joint 100. As would be understood by a person skilled in the art, the well-servicing fluid pump rates need to be sufficient to create a fluid velocity that will carry debris up through the center bore of the clean-out string. At the same time that the well is being reverse circulated, the clean-out string is rotated to create a grinding action if a clean-out bit is used, or to create additional well-bottom turbulence when a clean-out bit is not used, or to increase the dynamic impact of the scale or debris with the projections, where common industry practice would determine the rotation rate. Projection 3 of tubing joint 100 are impacted by debris as the debris is carried up through the clean-out string. The rotating action of the clean-out string increases the debris-impacting performance of the tubing joint 100. As the debris impacts the projection 3, the debris is broken apart into smaller pieces, greatly reducing the potential that the debris will bridge off and clog the clean-out string. Upon completion of the clean out, the clean-out string is pulled out of the well bore, and the tubing joint 100 is inspected and set aside for use in another well service job. The service string is then reinserted into the well bore and well put back into service.

The tubing joint 100 may be used in a completion string. The tubing joint 100 may be used in an oil and/or gas well. The tubing joint 100 may be used to break up debris in a fluid in an oil and/or gas well, where the fluid may be a drilling fluid or a clean out fluid and the debris may comprise hard scale.

Generally, the downhole tool may be used with tubulars, including but not limited to pipe, drill pipe, tubing, coiled tubing, jointed tubing. Generally, the downhole tool may be rotated if, and as necessary from the surface, for example by a top drive or rotary table. The downhole tool may be used with tubulars rotated proximate the downhole tool, for example by a mud motor or downhole-motor, but such arrangement would require an ability to reverse circulate and accommodate the debris. Accordingly, rotation of the tubular (and tool) from the surface is preferred. The supply of well servicing fluid, and circulation or reverse circulation, as the case may be, as well as the removal of debris from the well servicing fluid, is provided from/at surface. The downhole tool may form part of the string or may be at or near the bottom end of the string. One or more of the downhole tools may be provided in the string.

Generally, in an embodiment disclosed, the projections may consist of cutting tools, cutting inserts and/or cutting elements, for example made of tungsten carbide (WC), blended tungsten carbide-cobalt or cemented carbide products, for example but not limited to shaped inserts that may be attached to the inside of the tubular by welding, bonding or brazing.

Apart from hard scale, well-bottom debris may be loose debris that may originate from one or more sources within or associated with the wellbore. It may be hard debris that originates from within the completed formation or from formation fluids. Occasionally, hard scale or well-bottom debris could result from mechanical debris from wellbore components. It could be scale, consolidated or unconsolidated sand, iron sulfides, wax or a combination of one or more of the above. When the material is hard, the disclosed tool and methods break it up.

Embodiment 1. A tubing joint, comprising a downhole tubular, defining a bore therethrough; and a projection coupled to the tubular and extending into the bore, the projection forming a partial obstruction of the bore, adapted to engage and break apart debris in a fluid flowing through the bore.

Embodiment 2. The joint of embodiment 1, wherein the projection extends radially into the bore.

Embodiment 3. The joint of embodiment 1 or 2, wherein the projection comprises a plurality of projections.

Embodiment 4. The joint of embodiment 3, wherein each of the plurality of projections is circumferentially displaced relative to each other.

Embodiment 5. The joint of embodiment 3 or 4, wherein each of the plurality of projections is longitudinally displaced relative to each other.

Embodiment 6. The joint of any one of embodiments 3 to 5, wherein each of the plurality of projections is circumferentially and longitudinally displaced relative to each other to spiral within the bore.

Embodiment 7. The joint of any one of embodiments 1 to 6, wherein the projection extends into the bore between about 10 percent and about 30 percent of the diameter of the bore.

Embodiment 8. The joint of embodiment 7, wherein the projection extends into the bore between about 15 percent and about 25 percent of the diameter of the bore.

Embodiment 9. The joint of embodiment 8, wherein the projection extends into the bore about 20 percent of the diameter of the bore.

Embodiment 10. The joint of any one of embodiments 1 to 9, wherein the projection is substantially frustoconical shaped.

Embodiment 11. The joint of any one of embodiments 1 to 9, wherein the projection is substantially cone shaped.

Embodiment 12. The joint of any one of embodiments 1 to 9, wherein the projection is substantially wedge tipped.

Embodiment 13. The joint of any one of embodiments 1 to 9, wherein the projection is substantially nub shaped.

Embodiment 14. The joint of any one of embodiments 1 to 13, wherein the projection is composed of tungsten carbide, carbon steel, stainless steel, hardened metal or combinations thereof.

Embodiment 15. The joint of any one of embodiments 1 to 14, wherein the projection is welded to the tubular.

Embodiment 16. The joint of any one of embodiments 1 to 14, wherein the projection is integral with the tubular.

Embodiment 17. The joint of any one of embodiments 1 to 16, wherein the tubular is a joint of tubing.

Embodiment 18. The joint of any one of embodiments 1 to 17, wherein the tubular has a pin fitting at a first end and a bell fitting at a second end.

Embodiment 19. Use of the tubing joint of any one of embodiments 1 to 18 in a clean out string to remove debris from a wellbore.

Embodiment 20. Use of the tubing joint of any one of embodiments 1 to 18 to break up debris in a fluid in a well.

Embodiment 21. The use of embodiment 19 or 20, wherein the debris comprises hard scale.

Embodiment 22. A method for servicing a well having a defined wellbore containing debris, comprising: inserting a clean-out string into the wellbore, the clean-out string including a tubing joint of any one of embodiments 1 to 18; and reverse circulating a fluid through the well; and rotating the tubing joint to engage the debris with the projection within the bore, wherein at least a portion of the debris is thereby broken apart into broken debris.

Embodiment 23. The method of embodiment 22, further comprising carrying the broken debris out of the well with the fluid.

Embodiment 24. The method of embodiments 22 or 23, wherein inserting the clean-out string into the wellbore comprises positioning the tubing joint within the wellbore proximate the debris.

Embodiment 25. The method of any one of embodiments 22 to 24, wherein inserting the clean out string into the wellbore comprises positioning the tubing joint within the wellbore along a bottom portion of the wellbore.

Embodiment 26. The method of any one of embodiments 22 to 25, wherein the fluid is a drilling fluid or a well servicing fluid.

Embodiment 27. The method of any one of embodiments 22 to 26, wherein the well is an oil well, a gas well, an oil and gas well, or a water well.

Embodiment 28. The method of any one of embodiments 22 to 27, wherein the debris comprises hard scale or well-bottom debris or both.

The embodiments described herein are intended to be examples only.

Alterations, modifications and variations can be effected to the particular embodiments by those of skill in the art. The scope of the claims should not be limited by the particular embodiments set forth herein, but should be construed in a manner consistent with the specification as a whole.

All publications, patents and patent applications mentioned in this specification are indicative of the level of skill those skilled in the art to which this invention pertains and are herein incorporated by reference to the same extent as if each individual publication patent, or patent application was specifically and individually indicated to be incorporated by reference.

The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modification as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.

Claims

1. A tubing joint, comprising

a downhole tubular, defining a bore therethrough; and

a projection coupled to the tubular and extending into the bore, the projection forming a partial obstruction of the bore, adapted to engage and break apart debris in a fluid flowing through the bore.

2. The joint of claim 1, wherein the projection extends radially into the bore.

3. The joint of claim 2, wherein the projection comprises a plurality of projections.

4. The joint of claim 3, wherein each of the plurality of projections is circumferentially displaced relative to each other.

5. The joint of claim 4, wherein each of the plurality of projections is longitudinally displaced relative to each other.

6. The joint of claim 5, wherein each of the plurality of projections is circumferentially and longitudinally displaced relative to each other to spiral within the bore.

7. The joint of claim 6, wherein the projection extends into the bore between about 10 percent and about 30 percent of the diameter of the bore.

8. The joint of claim 7, wherein the projection extends into the bore between about 15 percent and about 25 percent of the diameter of the bore.

9. The joint of claim 8, wherein the projection extends into the bore about 20 percent of the diameter of the bore.

10. The joint of claim 9, wherein the projection is substantially frustoconical-shaped.

11. The joint of claim 9, wherein the projection is substantially cone-shaped.

12. The joint of claim 9, wherein the projection is substantially wedge-tipped.

13. The joint of claim 9, wherein the projection is substantially nub-shaped.

14. The joint of claim 9, wherein the projection is composed of tungsten carbide, carbon steel, stainless steel, hardened metal or combinations thereof.

15. The joint of claim 14, wherein the projection is welded to the tubular.

16. The joint of claim 14, wherein the projection is integral with the tubular.

17. The joint of claim 9, wherein the tubular is a joint of tubing.

18. The joint of claim 17, wherein the tubular has a pin fitting at a first end and a bell fitting at a second end.

19. In a tubing joint, comprising:

a downhole tubular, defining a bore therethrough; and

a projection coupled to the tubular and extending into the bore, the projection forming a partial obstruction of the bore, adapted to engage and break apart debris in a fluid flowing through the bore, the use of the tubing joint in a clean-out string to remove debris from a wellbore.

20. The use of claim 19, wherein the debris comprises hard scale.

21. In a tubing joint, comprising:

a downhole tubular, defining a bore therethrough; and

a projection coupled to the tubular and extending into the bore, the projection forming a partial obstruction of the bore, adapted to engage and break apart debris in a fluid flowing through the bore, the use of the tubing joint to break up debris in a fluid in a well.

22. The use of claim 21, wherein the debris comprises hard scale.

23. A method for servicing a well having a defined wellbore containing debris, comprising:

inserting a clean-out string into the wellbore, the clean-out string including a tubing joint comprising: a downhole tubular, defining a bore therethrough; and a projection coupled to the tubular and extending into the bore, the projection forming a partial obstruction of the bore, adapted to engage and break apart debris in a fluid flowing through the bore; and

reverse circulating a fluid through the well; and

rotating the tubing joint to engage the debris with the projection within the bore,

wherein at least a portion of the debris is thereby broken apart into broken debris.

24. The method of claim 23, further comprising carrying the broken debris out of the well with the fluid.

25. The method of claim 24, wherein inserting the clean-out string into the wellbore comprises positioning the tubing joint within the wellbore proximate the debris.

26. The method of claim 25, wherein inserting the clean-out string into the wellbore comprises positioning the tubing joint within the wellbore along a bottom portion of the wellbore.

27. The method of claim 26, wherein the fluid is a drilling fluid or a well-servicing fluid.

28. The method of claim 23, wherein the well is an oil well, a gas well, an oil and gas well, or a water well.

29. The method of claim 23, wherein the debris comprises hard scale or well-bottom debris or both.