Downhole Fishing

Abstract

Apparatus and methods for performing downhole fishing. The apparatus may be a downhole tool having a fishing tool operable to connect with a target component in a wellbore and a plurality of arms each independently deployable into contact with a sidewall of the wellbore to facilitate connection of the fishing tool with the target component by radially moving the fishing tool relative to the target component.

What is claimed is: 
     
         1 . An apparatus comprising:
 a downhole tool comprising:
 a fishing tool operable to connect with a target component in a wellbore; and 
 a plurality of arms each independently deployable into contact with a sidewall of the wellbore to facilitate connection of the fishing tool with the target component by radially moving the fishing tool relative to the target component. 
   
     
     
         2 . The apparatus of  claim 1  further comprising a conveyance element extending from the downhole tool to a wellsite surface from which the wellbore extends, wherein the downhole tool is controllable from the wellsite surface via telemetry on the conveyance element. 
     
     
         3 . The apparatus of  claim 2  wherein the conveyance element comprises a single wire covered by an electrical insulation, wherein the wire is operable to transmit electrical signals between the downhole tool and the wellsite surface. 
     
     
         4 . The apparatus of  claim 1  wherein the arms are collectively operable to move the fishing tool along a plane coincident with a diameter of the wellbore. 
     
     
         5 . The apparatus of  claim 1  wherein the downhole tool further comprises a plurality of actuators each associated with a corresponding one of the arms, and wherein each actuator is independently operable to move the corresponding arm independently with respect to the other arms. 
     
     
         6 . The apparatus of  claim 1  wherein the downhole tool further comprises a plurality of position sensors each operable to generate a signal or information indicative of a current position of a corresponding one of the arms. 
     
     
         7 . The apparatus of  claim 1  wherein the downhole tool further comprises a sensor operable to generate a signal or information indicative of connection between the fishing tool and the target component. 
     
     
         8 . The apparatus of  claim 7  further comprising a conveyance element extending between the downhole tool and the wellsite surface from which the wellbore extends, wherein the sensor is or comprises a tension sensor operable to generate a signal or information indicative of tension applied to the downhole tool by the conveyance element. 
     
     
         9 . The apparatus of  claim 1  wherein the downhole tool further comprises a downhole power source operable to supply power for deploying the arms into contact with the sidewall of the wellbore. 
     
     
         10 . The apparatus of  claim 1  wherein:
 the downhole tool further comprises a telemetry module operable to:
 transmit signals or information to the wellsite surface; and/or 
 receive signals or information from the wellsite surface; 
 
 the transmitted signals or information are indicative of:
 position of each one of the arms; 
 position of the fishing tool within the wellbore; 
 tension applied to the downhole tool via means for conveying the downhole tool within the wellbore; and/or 
 an image of the downhole tool, and 
 
 the received signals or information are indicative of:
 intended position of each one of the arms; and/or 
 intended position of the fishing tool within the wellbore. 
 
 
     
     
         11 . A method comprising:
 conveying a downhole tool within a wellbore from a wellsite surface to a target component in the wellbore, wherein the downhole tool comprises:
 a fishing tool; and 
 a plurality of arms; 
   operating the arms to move into contact with a sidewall of the wellbore to facilitate connection of the fishing tool with the target component;   connecting the fishing tool with the target component; and   retrieving the downhole tool and the target component to the wellsite surface.   
     
     
         12 . The method of  claim 11  wherein facilitating connection of the fishing tool with the target component comprises radially moving the fishing tool relative to the target component into substantial axial alignment with the target component. 
     
     
         13 . The method of  claim 12  wherein connecting the fishing tool with the target component comprises, after the fishing tool is substantially axially aligned with the target component, moving at least a portion of the downhole tool in a downhole direction until the fishing tool engages with the target component. 
     
     
         14 . The method of  claim 11  wherein facilitating connection of the fishing tool with the target component comprises moving the fishing tool to different lateral positions within the wellbore until the fishing tool is axially aligned with the target component. 
     
     
         15 . The method of  claim 14  wherein connecting the fishing tool with the target component comprises attempting to connect the fishing tool with the target component at each one of the different lateral positions within the wellbore until the fishing tool connects with the target component. 
     
     
         16 . The method of  claim 11  wherein facilitating connection of the fishing tool with the target component comprises moving the fishing tool along a plane coincident with a diameter of the wellbore. 
     
     
         17 . The method of  claim 11  wherein conveying the downhole tool within the wellbore is performed via a single wire covered by an electrical insulation, and wherein operating the arms comprises transmitting electrical control signals between the downhole tool and the wellsite surface via the wire to control movement of the arms. 
     
     
         18 . The method of  claim 11  wherein operating the arms comprises operating each one of the arms to move independently with respect to the other arms. 
     
     
         19 . The method of  claim 11  further comprising:
 applying tension to at least a portion of the downhole tool; and 
 monitoring the tension to determine if the fishing tool is connected with the target component. 
 
     
     
         20 . The method of  claim 11  further comprising:
 telemetering first signals or information from downhole to surface, wherein the first signals are indicative of:
 lateral position of each one of the arms; 
 lateral position of the fishing tool within the wellbore; 
 tension applied to the tool string; and/or 
 tension applied to the target component; and 
 
 telemetering second signals or information from surface to downhole, wherein the second signals are indicative of:
 intended lateral position of each one of the arms; and/or 
 intended lateral position of the fishing tool within the wellbore.