Encapsulating an electric submersible pump cable in coiled tubing

Abstract

An electric submersible pump (ESP) cable encapsulated in coiled tubing is provided. In an example process, ESP cable is drawn through coiled tubing. Liquid filler that cures into a supportive solid matrix is pumped into the coiled tubing. The solid matrix may be a rubberized filler or a closed-cell foam. Additives in the liquid filler can compensate for thermal expansion during operation of the ESP, or decrease overall weight of the solid matrix, or swell in the presence of oil, water, salt, or gas to seal a hole in the coiled tubing. The coiled tubing may be formed and seam-welded around the ESP cable from flat steel strip. A long coiled tubing resistant to stretch for deep wells may be produced by providing extra ESP cable for slack before the liquid filler cures into solid matrix. The coiled tubing may be clad with corrosion-resistant alloy for corrosive wells.

What is claimed is: 
     
         1 . An apparatus, comprising:
 a coiled tubing for deploying an electrical apparatus in a well;   a cable in the coiled tubing in communication with the electrical apparatus; and   a liquid filler occupying a space between an outside of the cable and an inside of the coiled tubing, the liquid filler curing into a supportive solid matrix.   
     
     
         2 . The apparatus of  claim 1 , wherein the cable powers the electrical apparatus and the electrical apparatus comprises an electric submersible pump (ESP). 
     
     
         3 . The apparatus of  claim 1 , wherein the supportive solid matrix comprises a rubberized filler. 
     
     
         4 . The apparatus of  claim 1 , wherein the supportive solid matrix comprises a closed-cell foam matrix. 
     
     
         5 . The apparatus of  claim 1 , wherein the supportive solid matrix comprises one of an epoxy, a silicone, an ether, an ester, a liquid fluorosilicone, a liquid fluoroelastomer, a SHIN-ETSU-SIFEL potting gel, a urethane, or a polymer that solidifies over time or when exposed to heat. 
     
     
         6 . The apparatus of  claim 1 , wherein the supportive solid matrix further comprises an additive compensating for thermal expansion of the cable during an operation of the electrical apparatus. 
     
     
         7 . The apparatus of  claim 1 , wherein the supportive solid matrix further comprises an additive for decreasing a weight of the supportive solid matrix, including one of a chopped carbon fiber, a glass fiber, a synthetic fiber, glass beads with air, formed particles, or chopped formed particles. 
     
     
         8 . The apparatus of  claim 1 , wherein the supportive solid matrix further comprises an additive to swell in the presence of one of an oil, water, a salt, or a gas to seal off a hole in the coiled tubing. 
     
     
         9 . The apparatus of  claim 1 , wherein the liquid filler cures into the supportive solid matrix due to an elapse of time or when exposed to heat. 
     
     
         10 . The apparatus of  claim 1 , wherein the supportive solid matrix remains pliable and deformable in response to a stretch or a movement of the cable in relation to the coiled tubing, or in response to a deformation of the coiled tubing deviating around a spool, a reel, a drum, a well head, a goose neck, an injector, a joint, a casing, an annulus, a well wall, a well curve, a hangar, a termination, or a sheave. 
     
     
         11 . The apparatus of  claim 1 , wherein the cable comprises one of a round cable, a flat cable, a coaxial cable, or a helically coiled cable. 
     
     
         12 . The apparatus of  claim 1 , wherein the coiled tubing comprises a seam-welded tube formed over the cable and an excess of the cable comprising a slack. 
     
     
         13 . The apparatus of  claim 1 , wherein the coiled tubing further comprises a corrosion resistant cladding. 
     
     
         14 . The apparatus of  claim 13 , further comprising a low-carbon steel coiled tubing and a metallic bonding layer added on the low-carbon steel coiled tubing, wherein the corrosion resistant cladding bonds to the low-carbon steel coiled tubing via a chemical affinity with the metallic bonding layer and an associated heat of reaction from the chemical affinity. 
     
     
         15 . A method, comprising:
 pulling a cable into a coiled tubing for deploying an electrical apparatus in a well; and   pumping a liquid filler that cures into a solid matrix into the coiled tubing to secure the cable in relation to the coiled tubing.   
     
     
         16 . The method of  claim 15 , wherein the solid matrix comprises one of a rubberized filler or a closed-cell-foam. 
     
     
         17 . The method of  claim 15 , further comprising drawing the coiled tubing down onto the solid filler when air gaps cause separation between the solid filler and the coiled tubing. 
     
     
         18 . A method, comprising:
 shaping a continuous piece of flat metal around a cable for communicating power or data to an electrical apparatus in a well;   seam-welding the continuous piece of metal into a coiled tubing around the cable; and   pumping a liquid filler that cures into a solid filler into the coiled tubing to secure the cable in relation to the coiled tubing.   
     
     
         19 . The method of  claim 18 , further comprising shaping the continuous piece of flat metal around an excess of the cable to provide a slack for the cable when the coiled tubing stretches under an increased weight in a deep well application. 
     
     
         20 . The method of  claim 18 , further comprising cladding an outside surface of the coiled tubing with a corrosion-resistant metal or alloy to resist a chemical corrosion.