PIPE REPAIR TOOL AND RELATED METHODS

Abstract

A pipe repair tool includes at least two saddles having an actuatable cylinder disposed therebetween and configured to fit within the pipe, the at least two saddles including arcuate surfaces configured to correspond with a circumference of the pipe.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation-in-Part of U.S. patent application Ser. No. 12/940,609, entitled “Pipe Repair Tool and Related Methods” filed Nov. 5, 2010, which is incorporated by reference herein in its entirety.

BACKGROUND

1. Field of the Disclosure

Embodiments disclosed herein relate generally to a pipe repair tool used for general field repairs. In particular, embodiments disclosed herein relate to a pipe repair tool for repairing out-of-round pipe sections.

2. Background Art

Casing, tubing, joints, liners, drill pipe, drill collars, pup joints, and line pipe (collectively referred to as pipe) may be used in the oil and gas industry to retrieve and transport liquid and gas products. Pipe joints, for example, may be positioned in a wellbore to stabilize formations or transport referenced products. The pipe joints may be coupled in an end-to-end manner by threaded connections, welded connections, or other connections known in the art.

During transport of the pipe from the manufacturer's facility to a customer, the pipe may become damaged due to excessive movement. In particular, the pipe ends may be the most susceptible to damage, for example, indentations in the circumference of the pipe end. Typically, damaged pipe ends may be classified as “rejects” and must be transported to a certified threading or end prep facility whereby the pipe end is cut-off and machined to satisfy specification requirements. Thus, machining of the pipe ends at a certified facility as indicated is essentially doubled due to the fact that the threading operation was performed twice, in addition to product transportation and handling.

Further, certain lower quality pipe may have certain areas along its length where a circumference of the pipe is “out-of-round,” i.e., the circumference may have a degree of ovality. Oftentimes, particularly if the defect is near a central portion of the pipe and thus cutting off the out-of-round end cannot be used to remedy this, the entire pipe length may be scrapped.

Accordingly, there exists a need for a tool capable of repairing damaged pipe ends or out-of-round pipe sections to avoid the need for complete re-machining of the pipe ends.

SUMMARY OF THE DISCLOSURE

In one aspect, embodiments disclosed herein relate to a pipe repair tool including at least two saddles having an actuatable cylinder disposed therebetween and configured to fit within the pipe, the at least two saddles including arcuate surfaces configured to correspond with a circumference of the pipe.

In other aspects, embodiments disclosed herein relate to a method of repairing pipe, the method including aligning opposing saddles of a pipe repair tool within an out-of-round pipe section, wherein the out-of-round pipe section comprises a short axis and a long axis substantially perpendicular thereto, and wherein the saddles are substantially aligned with the short axis of an out-of-round pipe circumference. The method further includes radially expanding the saddles against an inner wall of the pipe section in a direction substantially parallel with the short axis of the out-of-round pipe circumference, wherein the short axis and the long axis of the out-of-round pipe section are substantially equal after radial expansion of the saddles.

Other aspects and advantages of the invention will be apparent from the following description and the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A-1C show perspective views of a pipe repair tool for a pipe coupling in accordance with one or more embodiments of the present disclosure.

FIGS. 2A-2C show perspective views of a pipe repair tool for a pipe pin end in accordance with one or more embodiments of the present disclosure.

FIG. 3A shows an out-of-round pipe section to be repaired in accordance with one or more embodiments of the present disclosure.

FIG. 3B shows a repaired round pipe section in accordance with one or more embodiments of the present disclosure.

DETAILED DESCRIPTION

In one aspect, embodiments disclosed herein relate to a pipe repair tool used in general field repairs. In particular, embodiments disclosed herein relate to a pipe repair tool that may be used for de-denting damaged pipe ends. Further, embodiments disclosed herein relate to a pipe repair tool that may be used to expand out-of-round pipe sections. In general, the pipe repair tool may be used with a number of different pipe sizes ranging from 2⅜ inches up to 36 inches, and larger.

Referring now to FIGS. 1A-1C, perspective views of a pipe repair tool 100 used for repairing a coupling 50 or box type pipe end having internal threads 51 in accordance with one or more embodiments of the present disclosure are shown. The pipe repair tool 100 includes two saddles, an upper saddle 102 and a lower saddle 104. As shown, the saddles 102, 104 are configured in a semi-circle shape having arcuate-shaped outer surfaces 103, 105, respectively, which are configured to correspond to a circumference of an inner surface 51 of a pipe coupling 50. Stated otherwise, the outer arcuate surfaces 103, 105 of upper and lower saddles 102, 104 may be configured to be concentric with the circumference of the inner surface 51 of the coupling 50. The upper and lower saddles 102, 104 may be configured having a radial thickness (measured in the z-direction) dependent upon a wall thickness of the pipe end to be repaired. In certain embodiments, the radial thickness of the upper and lower saddles 102, 104 may be at least twice the wall thickness of the pipe end to be repaired.

Further, in certain embodiments, the upper and lower saddles 102, 104 may be configured having threaded outer surfaces 103, 105, respectively, which are configured to correspond with a thread profile of the internal threads 51 of the coupling 50 (FIG. 1A). The threaded outer surfaces 103, 105 may be configured to correspond with any number of the various thread profiles known in the art. In addition, the upper and lower saddles 102, 104 may be configured having a counterbore profile at an end 109 that is configured to correspond to a counterbore 53 in a distal end of the pipe coupling 50. Those skilled in the art will appreciate a number of API standard counterbores to which the end 109 of the upper and lower saddles 102, 104 may be matched.

The pipe repair tool 100 further includes an actuatable cylinder 106 disposed between the upper and lower saddles 102, 104, and which is configured to expand or extend the upper and lower saddles 102, 104 in opposite directions. The actuatable cylinder 106 (FIG. 1B) may be secured between the upper and lower saddles 102, 104 in any number of ways as known to those or ordinary skill in the art. In certain embodiments, the actuatable cylinder 106 may be a hydraulic jack. As an example, a low-height, single-acting cylinder available from Enerpac®, located in Butler, Wis., may be used as the actuatable cylinder 106. Further, an external power source such as a hydraulic pump, electric pump, manual hand pump, or hydraulic air pump, also available from Enerpac®, may be used to actuate the hydraulic jack. The actuatable cylinder 106 is disposed between the upper and lower saddles 102, 104 such that a piston (not shown) within the actuatable cylinder 106 may be extended and force the upper saddle 102 away from the lower saddle 104. In certain embodiments, the actuatable cylinder 106 may be rated to provide up to 10,000 psi, or greater. Moreover, in certain embodiments, the actuatable cylinder may be rated up to about 100 tons, or greater. Alternatively, any type of actuatable cylinder known to those skilled in the art may be used in accordance with embodiments disclosed herein.

The pipe repair tool 100 may further include one or more alignment tracks 108 that are configured to maintain an alignment between the upper and lower saddles 102, 104 in a radial direction (i.e., in the z-direction). The alignment tracks 108 provide that the upper saddle 102 and lower saddle 104 move directly away from and toward each other (i.e., in substantially 180 degree directions) as the actuatable cylinder 106 expands and retracts. The alignment tracks 108 prevent the upper and lower saddles 102, 104 from becoming misaligned and binding. Those skilled in the art will appreciate a number of various configurations of alignment tracks that may be used in accordance with one or more embodiments disclosed herein.

Still further, the upper and lower saddles 102, 104 may include attachment points 110 where a linkage (not shown) may be connected to secure the upper and lower saddles 102, 104 together. For example, the linkage may include, but is not limited to, a flexible linkage such as a chain, flexible strap, or other flexible linkages known to those skilled in the art. Further, the pipe repair tool 100 may include an extension arm 112 that protrudes axially (i.e., in the y-direction) from the pipe repair tool 100. As shown, the extension are 112 may be attached to the lower saddle 104, however, alternatively the extension arm 112 may be attached at any convenient location on the pipe repair tool 100. The extension arm 112 allows the pipe repair tool to be inserted into a pipe up to a greater distance axially into the pipe length, rather than merely at the pipe end.

Referring briefly to FIG. 2A, a perspective view of pipe repair tool 200 used for repairing a pin end 60 of a pipe having external threads 61 in accordance with one or more embodiments of the present disclosure is shown. The pipe repair tool 200 includes an upper saddle 202, a lower saddle 204, and an actuatable cylinder 206 (FIG. 2B) disposed therebetween. In this embodiment, the outer arcuate surfaces 203, 205 of the upper and lower saddles 202, 204, respectively, are smooth (i.e., no threaded surface) to correspond with the smooth inner surface of the pin end 60 (due to the pin end 60 having external threads 61). In certain embodiments, the outer arcuate surfaces 203, 205 of the upper and lower saddles 202, 204 may substantially correspond with an inner circumference of the pipe, such that the saddles 202, 204 exert equal pressure about the circumference of the pipe during expansion of the saddles 202, 204. In alternate embodiments, the outer arcuate surfaces 203, 205 may be tapered along lengths thereof such that a diameter of the arcuate surfaces increases or decreases along lengths thereof. The pipe repair tool 200 further includes alignment tracks 208, attachment points 210, and an extension arm 212 similar to the previous embodiment described above.

Referring now to FIGS. 1A-1C and 2A-2C together, methods of using the pipe repair tools 100, 200 in accordance with one or more embodiments disclosed herein are as follows. As shown in FIGS. 1A and 2A, often a damaged pipe end 50, 60 will have an indentation 52, 62 that protrudes in a radially inward direction. A damaged pipe end 50, 60 with such an indentation 52, 62 is often classified as a reject and may not be used unless costly remanufacturing steps are undertaken (i.e., cutting the damaged end and rethreading). Using a pipe repair tool in accordance with methods disclosed herein, the damaged pipe end may be repaired such that the pipe length may be used.

The pipe end is first inspected to determine whether the pipe end is salvageable and if use of the pipe repair tool may be sufficient to repair the damage to the pipe end. For a damaged pipe coupling 50 (with internal threads 51), if the indentation area 52 (FIG. 1A) exceeds the first two threads axially inward from the coupling end, or if the internal threads 51 are detected to have encountered any tears, cut, grinds, shoulders, steps, or any other imperfections and/or damage that breaks the thread continuity in the indented area, or if any coupling face damage with raised metal is detected, the coupling 50 may likely remain in the reject category (i.e., the coupling is beyond repair). Likewise, for a damaged pin end 60 (with external threads 61), if the indentation area 62 (FIG. 2A) exceeds the second full crested thread from the pin nose face, or if the external threads 61 are detected to have encountered any tears, cuts, grinds, shoulders, steps, or any other imperfections and/or damage that breaks the thread continuity in the indented area, or if any pin end damage with raised metal is detected, the pin end 60 may likely remain in the reject category (i.e., the pin end is beyond repair).

Still further, for damaged plain end casing (not shown), if the indentation exceeds API Specification 5CT requirements for outer diameter (“OD”) dimensional requirements, the damaged plain end casing may remain in the reject category. Further, for damaged plain end line pipe, if the indentation exceeds API Specification 5L requirements, which state that pipe shall contain no indentations greater than ¼ inch (0.250 inch) measured as the distance between the lowest point of the indentation (i.e., the furthest point radially inward) and a prolongation of the original contour of the pipe, the damaged line pipe may remain in the reject category. If the damaged pipe end is determined to be repairable, the repairs may be commenced as follows.

To repair the damaged pipe end, the pipe may be rotated until the damaged area 52 (FIG. 1A) is located at approximately a 12 o'clock position (i.e., the indentation is on top). Next, the pipe repair tool 100 may be inserted into the pipe end as shown in FIG. 1B. The upper saddle 102 may be aligned with the indentation 52 such that the indentation 52 is positioned in approximately the center of the upper saddle 102. The lower saddle 104 is configured to engage a lower half of the pipe end circumference to provide a stable base during repair. The lower saddle 104 may be configured to have an arcuate outer surface 105 length of up to approximately ½ of the circumference of the pipe end. In general, the greater the length of the arcuate outer surface 105, the better stability the lower saddle 104 is able to provide during repair of the pipe end. Further, during repair of a pipe coupling having internal threads, the threaded outer surface 105 of the lower saddle 104 is matched to correspond with the internal threads 51 of the pipe coupling 50. The threaded outer surface 105 of the lower saddle 104 is matched with the internal threads 51 to avoid deforming the internal threads during repair.

Likewise, referring briefly to FIGS. 2A-2C, to repair a pin end 60 of a pipe the pipe repair tool 200 may be inserted into the pin end 60 and oriented such that the upper saddle 202 is approximately centered on the indentation 62. Because the pin end 60 has external threads 61, the upper and lower saddles 202, 204 have outer surfaces 203, 205 that are smooth and configured to correspond with the smooth inner surface of the pin end 60. Further, in certain embodiments, a shim (not shown) may be inserted between the upper and lower saddles 202, 204 and an inner surface of the pin end 60 to avoid direct contact between the outer surfaces 203, 205 of the upper and lower saddles 202, 204 and the inner surface of the pin end 60. The shim may be relatively thin and is intended to prevent any marring or deforming of the inner surface of the pin end 60.

After the pipe repair tool is properly positioned in the pipe end, the actuatable cylinder may be actuated and a piston within the actuatable cylinder expanded to urge the upper saddle into contact with an inner surface of the damaged section of the pipe end. In the embodiment shown in FIGS. 1A-1C, similar to the lower saddle 104, the upper saddle 102 is configured having a threaded outer surface 103 configured to correspond with the internal threads 51 of the pipe coupling 50. The upper saddle 102 is expanded to contact the damaged surface 52. The outward radial force from the expanding upper saddle 102 forces the indentation 52 of the damaged section radially outward and restores the pipe coupling 50 to its original outer diameter. Once the damaged section of the pipe coupling 50 reaches the original diameter contour, the pressure to the actuatable cylinder is released to allow the upper saddle 102 to retract away from the inner surface of the pipe end 50.

Still further, in certain embodiments, prior to relieving pressure in the actuatable cylinder and retracting the upper saddle, the upper saddle may remain in contact with the inner surface of the pipe end and the repaired pipe end may be work-hardened or strain-hardened. The repaired pipe end may be work-hardened to ensure that the repaired outer diameter contour is permanent and that the damaged section (i.e., the indentation) does not return to the damaged state whatsoever (i.e., that the indentation does not return). Any type of cold-working or work-hardening process may be used to induce slight permanent deformation of the metal and exact the shape change (i.e., return the pipe end to its original outer diameter contour). For example, repetitively struck blows from a large hammer on an outer surface of the repaired pipe end may effectively cold-work the pipe end.

Following repairs to the pipe end, an inspection of the repaired pipe end may be conducted to ensure that the repaired pipe end has been repaired to proper dimensions and within proper tolerances. A thread element and/or pipe end dimensional inspection may be performed to ensure compliance with respective API Specifications (e.g., API Specifications 5CT, 5B, 5L and 5A5) in addition to any customer specification requirements, as will be known and understood by one of ordinary skill in the art. For example, a ring gauge or plug gauge may be employed to confirm that the repaired pipe end meets API specification requirements. Those skilled in the art will understand the use of a ring or plug gauge to do so.

In other embodiments, the pipe repair tool may be used for cold worked circumference rounding (“CWCR”) at a particular section of the pipe length having an out-of-round circumference. The pipe repair tool may be used to cold work or return the out-of-round circumference back to a substantially round circumference. For example, referring to FIGS. 3A and 3B, cross-section views of an out-of-round pipe circumference (FIG. 3A) and round pipe circumference (FIG. 3B) are shown. As shown in FIG. 3A, the out-of-round pipe has a more oval circumference with a short axis, indicated by “S,” and a long axis, indicated by “L.” In contrast, a round pipe circumference, shown in FIG. 3B, has two substantially equal axes, indicated by “E.” In other embodiments, the pipe repair tool 100 may be used to cold work a pipe circumference having an indentation at one or more locations around the circumference of the pipe. For example, a “flat spot” or other defect or indentation may be cold worked using the pipe repair tool 100 in accordance with one more embodiments of the present disclosure.

The pipe repair tool 100, with the saddles 102 retracted, may be inserted into the pipe and positioned at a particular axial location along the pipe length to be cold worked (i.e., axially adjacent the out-of-round circumference). The saddles may be rotationally oriented in alignment with or along the short axis “S” as shown. As such, outward expansion of the saddles 102 (with actuatable cylinder) in the direction of the short axis “S,” indicated by arrows “1,” against the inner wall of the pipe length may force the walls radially outward, thereby cold working and returning the pipe circumference to a substantially round configuration shown in FIG. 3B.

To determine an amount of expansion exerted by the saddles, an initial measurement using a Pi tape, micrometer, or other known measurement devices, may be used prior to expansion to establish a baseline measurement from which a subsequent post-expansion measurement may be compared. After a first attempt at cold working of the out-of-round section, the Pi tape may be used again to record a measurement at the cold worked section. If enough expansion has occurred in the pipe circumference, the operation may cease. Otherwise, additional expansion strokes of the saddles may be required before the pipe section is back within a suitable round configuration. Those skilled in the art will understand pipe sections that may be deemed out-of-round according to various pipe and conduit standards, including but not limited to American Petroleum Institute (API) standards, American Society for Testing and Materials (ASTM) standards, American Water Works Association (AWWA) standards, and other domestic and foreign standards.

In certain embodiments, the saddles may be expanded a single time before the pipe circumference is back within round. In other embodiments, multiple expansions and retractions of the saddles may be required. In certain embodiments, the pipe circumference may be worked by between about one thousandth and about one hundred thousandths of an inch. In other embodiments, the pipe circumference may be worked by between about one thousandth and about sixty five thousandths of a inch. In still other embodiments, the pipe circumference may be worked by between about five thousandths and about twenty thousandths of an inch. Finally, in still further embodiments, the pipe circumference may be worked by between about ten thousandths and about twelve thousandths of an inch. For example, a high collapse pipe section (e.g., HCP110) having a wall thickness of about 0.472 inches may be cold worked up to about ninety thousandths of an inch in accordance with one or more embodiments of the present disclosure.

Advantageously, embodiments of the present disclosure provide a pipe repair tool capable of returning a damaged pipe end to original specifications as allowed by API specification standards. Particularly, embodiments disclosed herein eliminate the need to cut and rethread the pipe end due to minor repairable damage of the pipe end. Thus, the pipe repair tool may save repair costs of damaged pipe ends as well as decrease the time required to make the repair itself. Further, embodiments disclosed herein provide a pipe repair tool capable of cold worked circumference rounding for out-of-round or flat pipe sections, which return the pipe circumference to a substantially round circumference.

While the present disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as described herein. Accordingly, the scope of the disclosure should be limited only by the attached claims.

Claims

1. A pipe repair tool comprising:

at least two saddles having an actuatable cylinder disposed therebetween and configured to fit within the pipe, the at least two saddles comprising arcuate surfaces configured to correspond with a circumference of the pipe.

2. The pipe repair tool of claim 1, wherein the actuatable cylinder is configured to expand the at least two saddles in opposite directions.

3. The pipe repair tool of claim 1, wherein the arcuate surfaces of the at least two saddles are configured to be substantially concentric with the circumference of the pipe.

4. The pipe repair tool of claim 1, wherein an arc length of the arcuate surfaces is approximately one-half or less of the circumference of the pipe.

5. The pipe repair tool of claim 1, wherein the actuatable cylinder is a hydraulic cylinder.

6. The pipe repair tool of claim 1, further comprising an external power source in fluid communication with the actuatable cylinder.

7. The pipe repair tool of claim 1, further comprising at least one alignment member configured to maintain a radial alignment between the at least two saddles.

8. The pipe repair tool of claim 1, wherein a radial thickness of the at least two saddles is at least twice the wall thickness of the tubular.

9. The pipe repair tool of claim 1, further comprising at least one linkage between the at least two saddles.

10. The pipe repair tool of claim 1, wherein the actuatable cylinder is configured to provide a pressure of up to 10,000 psi.

11. The pipe repair tool of claim 1, wherein a profile of the at least two saddles is configured to correspond to a standard counter bore of the pipe.

12. The pipe repair tool of claim 1, wherein the arcuate surfaces of the at least two saddles are configured to provide equal pressures around a pipe circumference during expansion.

13. The pipe repair tool of claim 1, wherein the actuatable cylinder is configured to provide up to about 100 tons of force.

14. A method of repairing pipe, the method comprising:

aligning opposing saddles of a pipe repair tool within an out-of-round pipe section,

wherein the out-of-round pipe section comprises a short axis and a long axis substantially perpendicular thereto, and

wherein the saddles are substantially aligned with the short axis of an out-of-round pipe circumference; and

radially expanding the saddles against an inner wall of the pipe section in a direction substantially parallel with the short axis of the out-of-round pipe circumference;

wherein the short axis and the long axis of the out-of-round pipe section are substantially equal after radial expansion of the saddles.

15. The method of claim 14, further comprising work-hardening the section of the pipe having the indentation after returning the circumference of the pipe to the original outer diameter contour.

16. The method of claim 14, further comprising dimensionally inspecting the threaded pipe.

17. The method of claim 16, further comprising inserting a shim between an outer surface of the at least two saddles and an inner surface of the out-of-round pipe section.

18. The method of claim 16, further comprising providing threaded outer surfaces on the at least two saddles to correspond with an internal thread of the pipe section.

19. The method of claim 16, further comprising providing smooth outer surfaces on the at least two saddles to correspond with a smooth inner surface of the pipe section.

20. The method of claim 14, further comprising repairing the indentation according to API specification requirements.