Method and apparatus for supporting cables within coil tubing

Abstract

A method of hanging a cable within a coiled tubing string includes the steps of determining a length of coiled tubing required within a well having a wellhead; determining a length of a cable required within the coiled tubing, the cable having a structural component along the length of the cable sufficient to support the weight of the cable; cutting the tubing string and installing a hanger sub in the coiled tubing string toward the wellhead attachment section relative to the downhole end, the hanger sub comprising an inner shoulder that extends radially into the hanger sub and defines an opening; and attaching an outer shoulder to the cable and inserting the cable into the coiled tubing string until the outer shoulder of the cable engages the inner shoulder of the hanger sub such that the inner shoulder positions the cable below the outer shoulder.

What is claimed is: 
     
         1 . In combination:
 a cable having a first end and a second end, the cable comprising an elongate structural component along the length of the cable, the structural component being sufficient to support the weight of the cable, the cable comprising a bundle of continuous supply lines; and   a length of coiled tubing string having a wellhead end and a downhole end, the coiled tubing string having a first section and a second section connected by a hanger sub, the hanger sub defining a central bore and comprising an inner shoulder that extends radially into the central bore of the hanger sub, the cable having an outer shoulder capable of engaging the inner shoulder of the hanger sub, such that;   wherein the hanger sub comprises two or more apertures, at least one aperture comprising the inner shoulder that engages the elongate structural component, at least a portion of the bundle of continuous supply lines passing through a separate aperture of the two or more apertures, the elongate structural component structurally engaging the supply lines below the hanger sub.   
     
     
         2 . The combination of  claim 1 , wherein the outer profile of the hanger sub is in line with the outer profile of the coiled tubing string. 
     
     
         3 . The combination of  claim 1 , wherein the cable comprises a supply line. 
     
     
         4 . The combination of  claim 1 , wherein the second end of the cable has a downhole tool attached. 
     
     
         5 . The combination of  claim 4 , wherein the downhole tool is an electric submersible pump. 
     
     
         6 . The combination of  claim 1 , wherein the structural component comprises a metal capillary tube. 
     
     
         7 . The combination of  claim 1 , wherein at least one supply line from the bundle of continuous supply lines comprises a metal capillary tube, the metal capillary tube providing structural support to the supply lines. 
     
     
         8 . The combination of  claim 1 , wherein the cable comprises a resistive heating element. 
     
     
         9 . The combination of  claim 1 , wherein the hanger sub is installed at a distance of between 1 and 50 meters from the wellhead end. 
     
     
         10 . The combination of  claim 1 , wherein the hanger sub in the coiled tubing string is at a distance of between 5 and 25 meters from the wellhead end. 
     
     
         11 . The combination of  claim 1 , wherein the hanger sub in the coiled tubing string is positioned below the wellhead end of the coiled tubing string at a depth of between 1% and 5% of the wellbore depth. 
     
     
         12 . The combination of  claim 1 , wherein at least one of the inner shoulder of the hanger sub and the outer shoulder of the cable are slotted to prevent rotation of the cable. 
     
     
         13 . The combination of  claim 1 , wherein the weight of the cable is supported solely by the hanger sub when installed in the wellhead. 
     
     
         14 . The combination of  claim 1 , wherein, when the coiled tubing string is installed through a wellhead, the hanger sub is positioned below the wellhead. 
     
     
         15 . The combination of  claim 1 , wherein, when the coiled tubing string is installed through a wellhead, a majority of the cable is below the hanger sub. 
     
     
         16 . In combination:
 a cable having a first end and a second end, the cable comprising a structural component along the length of the cable, the structural component being sufficient to support the weight of the cable; and   a length of coiled tubing string having a wellhead end and a downhole end, the coiled tubing string having a first section and a second section connected by a hanger sub, the hanger sub defining a central bore and comprising an inner shoulder that extends radially into the central bore of the hanger sub, the cable having an outer shoulder capable of engaging the inner shoulder of the hanger sub;   wherein the hanger sub in the coiled tubing string is positioned below the wellhead end of the coiled tubing string at a depth of between 1% and 5% of the wellbore depth.   
     
     
         17 . The combination of  claim 16 , wherein the cable comprises a resistive heating element. 
     
     
         18 . The combination of  claim 16 , wherein, when the coiled tubing string is installed through a wellhead, the hanger sub is positioned below the wellhead. 
     
     
         19 . The combination of  claim 1 , wherein, when the coiled tubing string is installed through a wellhead, a majority of the cable is below the hanger sub.