Patent Publication Number: US-2016245033-A1

Title: Tool and method of operation for removing debris and/or a lodged tool from a wellbore

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit to U.S. Provisional Patent Application Ser. No. 62/118,602, filed Feb. 20, 2015, which is herein incorporated by reference. 
    
    
     BACKGROUND 
     1. Field of Disclosure 
     Embodiments of this disclosure generally relate to a tool and method of operation for removing debris and/or a lodged tool from a wellbore. 
     2. Description of the Related Art 
     There are a variety of tools used to facilitate the drilling, completion, and production of a wellbore. One such tool is a packer or a plug, which can be used to seal a portion of the wellbore as needed. It is often desired to retrieve these tools from the wellbore after use, which requires a “fishing” operation. A “fishing” operation utilizes a fishing tool that is lowered into the wellbore to engage and retrieve the tool. However, often times there is a significant amount of debris, including dirt, rock fragments, and other materials located on top of the tool, which lodge the tool within the wellbore and obstruct the fishing tool from engagement with a “fish” (or retrieval) portion of the tool. A separate wellbore operation may be required to remove the debris prior to conducting the “fishing” operation, which adds time and cost to the overall retrieval process. 
     Therefore, there is a need for a tool and method of operation for removing debris and/or a lodged tool from a wellbore in a single trip. 
     SUMMARY OF THE INVENTION 
     A tool and method of operation for removing debris and/or a lodged tool from a wellbore as described herein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited embodiments can be understood in detail, a more particular description of the embodiments, briefly summarized above, may be had by reference to the description of the embodiments below, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings are not to be considered limiting of its scope, for the embodiments may admit to other equally effective embodiments. 
         FIG. 1  illustrates a tool for removing debris and/or a lodged tool from a wellbore in a first operational position, according to one embodiment disclosed herein. 
         FIG. 2  illustrates cross-section  2 - 2  of  FIG. 1 . 
         FIG. 3  illustrates cross-section  3 - 3  of  FIG. 1 . 
         FIG. 4  illustrates the tool in a second operational position, according to one embodiment disclosed herein. 
         FIG. 5  illustrates the tool moved back into the first operational position, according to one embodiment disclosed herein. 
         FIG. 6  illustrates the tool engaging a lodged tool within a wellbore, according to one embodiment disclosed herein. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates a tool  100  for removing debris and/or a lodged tool from a wellbore  2  in a first position, according to one embodiment disclosed herein. The tool  100  can be lowered into the wellbore  2  on a work string  5 . Optionally, fluid can be pumped down through the work string  5  and the tool  100 , and circulated back up to the surface through an annulus  4  formed between the exterior of the tool  100  and the interior of the wellbore  2 . 
     The tool  100  includes an upper mandrel  10  that is coupled to the work string  5 . The upper mandrel  10  is rotationally fixed to a lower mandrel  30  by an outer sleeve  20 , one or more key members  25 , and one or more pin members  27 . Optionally, the upper mandrel  10  can be axially fixed to the outer sleeve  20  temporarily by one or more shearable members  18  that are disposed through the upper mandrel  10  and the outer sleeve  20  (also shown in  FIG. 3 ). Alternatively, or in addition, the upper mandrel can be axially fixed to the outer sleeve  20  temporarily by a detent mechanism  19 , which is coupled to the upper mandrel  10  and can be moved into and out of engagement with a groove  17  formed along with inner surface of the outer sleeve  20 . The lower end of the outer sleeve  20  is coupled to the lower mandrel  30  by a threaded connection. 
     The upper end of the outer sleeve is coupled to the upper mandrel  10  by the key and pin members  25 ,  27 . The key members  25  are disposed within one or more longitudinal slots  15  formed on the outer surface of the upper mandrel  10  (also shown in  FIG. 2 ). The pin members  27  are disposed through both the outer sleeve  20  and the key members  25 , as further illustrated in  FIG. 3 . Rotation of the upper mandrel  10  is transferred to the key members  25 , the pin members  27 , the outer sleeve  20 , and finally to the lower mandrel  30  to rotate a milling skirt  35  that is disposed at the lower end of the lower mandrel  30 . 
     As illustrated in  FIG. 2 , the detent mechanism  19  includes one or more ball members  12  that are biased by biasing members  13 , such as springs, into the groove  17  of the outer sleeve  20 . The biasing members  13  are disposed in recesses  14  formed in the upper mandrel  10 . A downward force applied to the upper mandrel  10 , such as by setting down the weight of the work string  5 , can force the ball members  12  into the recesses  14 , thereby compressing the biasing members  13 , and out of the groove  17  to allow the upper mandrel  10  to move relative to the outer sleeve  20 , the lower mandrel  30 , and the milling skirt  35 . Subsequently, the upper mandrel  10  can be moved back to the position where the ball members  12  re-engage the groove  17  to axially fix the upper mandrel  10  to the outer sleeve  20 . 
     Referring back to  FIG. 1 , the tool  100  can be rotated to rotate the milling skirt  35  and cut out at least a portion of a lodged tool  60  located within the wellbore  2 . For example, an upper portion of the lodged tool  60  can be cut out using the milling skirt  35  to expose a retrieval member  61  (also known as a “fish” portion) of the lodged tool  60  that can be engaged to dislodge the remainder of the lodged tool  60 . The milling skirt  35  is also used to cut and/or loosen debris located within the wellbore  2  and/or above the lodged tool  60  within the wellbore  2 . The milling skirt  35  may include one or more teeth and/or an abrasive outer surface, such as a carbide coating, for cutting lodged tools and/or loosening wellbore debris. Fluid is pumped down through the tool  100  and circulated back up to the surface through the annulus  4  to flush out cuttings and/or debris from the wellbore  2 . 
     A support member  16  is coupled to the lower end of the upper mandrel  10  to support the weight of the outer sleeve  20  and the lower mandrel  30  when the tool  100  is lowered into the wellbore  2 . The lower end of the outer sleeve  20  contacts the upper end of the support member  16  to transfer the weight to the upper mandrel  10  and thus the work string  5 . The support member  16  can prevent the weight of the lower mandrel  30  from being applied to the pin members  27  and/or the shear members  18  to prevent inadvertent shearing of the pin members  27  and/or the shear members  18 . 
     A hydraulic adapter  40  is coupled to the lower end of the upper mandrel  10  and is disposed within the lower mandrel  30 . A flow bore  41  of the hydraulic adapter  40  is in fluid communication with a flow bore  11  of the upper mandrel  10 . One or more flow paths  42  are disposed through the body of the hydraulic adapter  40  to provide fluid communication between the flow bore  41  and an annulus  43  formed between the exterior of the hydraulic adapter  40  and the interior of the lower mandrel  30 . 
     Fluid pumped down through the work string  5  flows into the flow bore  11  of the upper mandrel  10 , and then into the flow bore  41  of the lower mandrel  30 . Fluid in the flow bore  41  flows through the flow paths  42  into the annulus  43  formed between the hydraulic adapter  40  and the lower mandrel  30 . An upper seal  45  is located above the flow paths  42  to prevent fluid flow upward into the outer sleeve  20  across the upper seal  45 . A lower seal  46  is located below the flow paths  42  to prevent fluid flow downward into the lower mandrel  30  across the lower seal  46 . 
     The lower seal  46  is held against downward movement by a seal retainer  48  that is coupled to the lower mandrel  30 . One or more by-pass slots  44  are formed on the outer surface of the hydraulic adapter  40 . When the by-pass slots  44  are positioned adjacent to the seal  46 , fluid in the annulus  43  bypasses the seal  46  and flows out through the lower end of the lower mandrel  30 . 
     In addition to the flow paths  42 , the flow bore  41  of the hydraulic adapter  40  is also in fluid communication with a flow bore  51  of a fishing tool  50  that is coupled to the lower end of the hydraulic adapter  40 . Fluid from the flow bore  11  of the upper mandrel flows into the flow bore  41  of the hydraulic adapter  40 , through the flow bore  51  of the fishing tool  50 , and out through the lower end of the lower mandrel  30  to flush out cuttings and debris from the wellbore  2 . A nozzle  47  can be disposed at the outlet of the flow bore  41  to increase the flow rate of fluid flowing through the hydraulic adapter  40  and the fishing tool  50  to help flush out cuttings and debris from the wellbore  2 . 
     Once the tool  100  is lowered onto the lodged  60 , as illustrated in  FIG. 1 , and/or debris that inhibits further downward movement of the tool  100 , then the weight of the work string  5  can be set down onto the upper mandrel  10  to shear the shearable members  18  and/or disengage the detent mechanism  19  to allow the upper mandrel  10  (and the hydraulic adapter  40  and the fishing tool  50 ) to move downward relative to the outer sleeve  20  and the lower mandrel  30 . The upper mandrel  10  can be moved into a second operational position as illustrated in  FIG. 4  (the lodged tool  60  omitted for clarity), such that the by-pass slots  44  are located below the lower seal  46  so that fluid flow through the annulus  43  is closed and contained by both the upper and lower seals  45 ,  46 . The pressurized fluid flow contained within the annulus  43  can provide a pressure increase that indicates to an operator at the surface that the tool  100  is in the second operational position illustrated in  FIG. 4 . Optionally, the tool  100  can be raised up from the lodged tool  60  and/or debris a pre-determined distance before pumping fluid down into the wellbore  2  through the tool  100 . 
     Referring to  FIG. 4 , fluid pumped down the work string  5  (illustrated by reference arrow F) flows directly through the flow bores  11 ,  41  and into flow bore  51  (illustrated by reference arrow F 2 ), as well as through flow paths  42  and into the annulus  43  (illustrated by reference arrow F 1 ), which provides a positive downward force onto the lower seal  46 , the seal retainer  48 , the lower mandrel  30 , and the milling skirt  35 . The fluid pumped out of the lower end of the lower mandrel  30  is circulated back up through the annulus  4  of the wellbore  2 . The tool  100  is rotated simultaneously so that the milling skirt  35  cuts and/or looses debris that can be circulated back up to the surface for removal. 
     During operation, the work string  5  does not need to lower the tool  100  as the lodged tool  60  (omitted for clarity in  FIG. 4 ) is cut out and/or as debris is removed because a positive downward force is applied to the lower mandrel  30  when fluid is pumped through the tool  100 . The seal area across the lower seal  46  is less than the seal area across the upper seal  45  such that a positive downward force is applied to the lower mandrel  30  when the annulus  43  is pressurized between the upper and lower seals  45 ,  46 . As the portion of the lodged tool and/or debris is cut and circulated out, the lower mandrel  30  and the milling skirt  35  moves downward relative to the upper mandrel  10 , the hydraulic adapter  40 , and the fishing tool  50 . 
     Referring to  FIG. 5 , as the milling skirt  35  continues to cut out an upper portion the lodged tool  60  (omitted for clarity) and/or debris, the lower seal  46  moves with the lower mandrel  30  to a position where the by-pass slots  44  allow fluid within the annulus  43  to by-pass the lower seal  46  as illustrated by reference arrow F 1 . Re-opening fluid flow across the lower seal  46  through the by-pass slots  44  provides a pressure decrease that indicates to an operator at the surface that the tool  100  is back in the first operational position illustrated in  FIG. 1 . Fluid can be circulated continuously through the tool  100  and the annulus  4  to flush out cuttings and/or debris from the wellbore. 
     Referring to  FIG. 6 , the retrieval member  61  of the lodged tool  60  is fully exposed after cutting and removing the surrounding portions of the lodged tool  60  and/or debris from the wellbore  2  operating the tool  100  as described herein. The weight of the work string  5  can be set down onto the upper mandrel  10 , to release the detent mechanism  19  if re-engaged, and thereby lower the hydraulic adapter  40  and the fishing tool  50  relative to the lower mandrel  30 . The lower mandrel  30  is inhibited from downward movement by contact with the lodged tool  60 . The fishing tool  50  is lowered until a gripping member  52  of the fishing tool  50  engages the retrieval member  61 . The work string  5  can then be raised to pull on the retrieval member  61  via the gripping member  52  to dislodge the lodged tool  60  and remove the lodged tool  60  from the wellbore  2 . 
     The tool  100  can be used to remove debris from a wellbore, remove a lodged tool from a wellbore, or remove both debris and a lodged tool from a wellbore. The debris and/or lodged tool can be removed in a single trip into the wellbore using the tool  100  described herein. The tool  100  can be moved between the various positions as illustrated and described with respect to  FIG. 1 ,  FIG. 4 , and  FIG. 5 , any number of times before moving the fishing tool  50  into engagement with the lodged tool  60  as illustrated and described with respect to  FIG. 6 . 
     While the foregoing is directed to various embodiments, other and further embodiments may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.