Patent Application
20120111082
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 dented pipe ends.
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.
Accordingly, there exists a need for a tool capable of repairing damaged pipe ends to avoid the need for complete re-machining of the pipe ends.
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 a damaged pipe end, the method including exerting a radially outward force against a section of the pipe having an indentation located in a circumference of the pipe and returning the circumference of the pipe to an original outer diameter contour.
Other aspects and advantages of the invention will be apparent from the following description and the appended claims.
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. 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
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 (
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 (
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
Referring now to
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 (
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 (
Likewise, referring briefly to
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
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.
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.
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.
