Dual-Walled Coiled Tubing Deployed Pump

Abstract

Dual-walled coiled tubing assemblies are used to dispose an electric device, such as an electric submersible pump into a wellbore. Dual-walled coiled tubing assemblies include an inner coiled tubing string and an outer coiled tubing string as well as a power cable.

What is claimed is: 
     
         1 . A dual-walled coiled tubing assembly to dispose an electric submersible pump into a wellbore, the dual-walled coiled tubing assembly comprising:
 an inner coiled tubing string defining an inner coiled tubing central axial pathway along its length;   an outer coiled tubing string radially surrounding the inner coiled tubing string, the outer coiled tubing string defining an outer coiled tubing string central axial passage along its length; and   a power cable to provide electric power to the electric device, the power cable being disposed within the outer coiled tubing string central axial passage.   
     
     
         2 . The dual-walled coiled tubing assembly of  claim 1  wherein the power cable is further disposed within the inner coiled tubing central axial passageway. 
     
     
         3 . The dual-walled coiled tubing assembly of  claim 1  wherein the power cable is disposed radially between the inner coiled tubing string and the outer coiled tubing string. 
     
     
         4 . The dual-walled coiled tubing assembly of  claim 1  further comprising one or more capillary lines disposed within the outer coiled tubing string. 
     
     
         5 . The dual-walled coiled tubing assembly of  claim 4  wherein the one or more capillary lines is/are located radially between the inner coiled tubing string and the outer coiled tubing string. 
     
     
         6 . The dual-walled coiled tubing assembly of  claim 4  wherein the one or more capillary lines is/are located radially within the inner coiled tubing string. 
     
     
         7 . The dual-walled coiled tubing assembly of  claim 4  wherein the one or more capillary lines is/are located within the power cable. 
     
     
         8 . The dual-walled coiled tubing assembly of  claim 1  further comprising separate first and second fluid flow paths defined within the outer coiled tubing string. 
     
     
         9 . The dual-walled coiled tubing assembly of  claim 1  further comprising at least one strap securing the power cable to the inner coiled tubing string. 
     
     
         10 . The dual-walled coiled tubing assembly of  claim 1  wherein the electric submersible pump assembly includes a pump section and a motor section. 
     
     
         11 . The dual-walled coiled tubing assembly of  claim 1  wherein the power cable presents an axial cross-section having:
 a first side surface that is concave and shaped to be generally complementary to an outer radial surface of the inner coiled tubing string; and 
 a second side surface that is convex and shaped to be generally complementary to an inner radial surface of the outer coiled tubing string. 
 
     
     
         12 . A hydrocarbon production assembly to produce hydrocarbon fluid from a wellbore, the production assembly comprising:
 an electric submersible pump;   a dual-walled coiled tubing assembly to dispose the electric submersible pump into the wellbore, the dual-walled coiled tubing assembly comprising:   an inner coiled tubing string defining an inner coiled tubing central axial pathway along its length;   an outer coiled tubing string radially surrounding the inner coiled tubing string, the outer coiled tubing string defining an outer coiled tubing string central axial passage along its length; and   a power cable to provide electric power to the electric submersible pump, the power cable being disposed within the outer coiled tubing string central axial passage.   
     
     
         13 . The hydrocarbon production assembly of  claim 12  wherein the power cable is further disposed within the inner coiled tubing central axial passageway. 
     
     
         14 . The hydrocarbon production assembly of  claim 12  wherein the power cable is disposed radially between the inner coiled tubing string and the outer coiled tubing string. 
     
     
         15 . The hydrocarbon production assembly of  claim 12  further comprising one or more capillary lines disposed within the outer coiled tubing string. 
     
     
         16 . The hydrocarbon production assembly of  claim 15  wherein the one or more capillary lines is/are located radially between the inner coiled tubing string and the outer coiled tubing string. 
     
     
         17 . The hydrocarbon production assembly of  claim 15  wherein the one or more capillary lines is/are located within the power cable. 
     
     
         18 . The hydrocarbon production assembly of  claim 12  further comprising separate first and second fluid flowpaths defined within the outer coiled tubing string. 
     
     
         19 . The hydrocarbon production assembly of  claim 12  further comprising at least one strap securing the power cable to the inner coiled tubing string. 
     
     
         20 . The hydrocarbon production assembly of  claim 12  wherein the power cable presents an axial cross-section having:
 a first side surface that is concave and shaped to be generally complementary to an outer radial surface of the inner coiled tubing string; and 
 a second side surface that is convex and shaped to be generally complementary to an inner radial surface of the outer coiled tubing string. 
 
     
     
         21 . The hydrocarbon production assembly of  claim 12  further comprising a packer forming a seal between the dual-walled coiled tubing assembly and the wellbore and wherein:
 an annulus is defined between the dual-walled coiled tubing assembly and the wellbore; and 
 production fluid is flowed through the annulus. 
 
     
     
         22 . The hydrocarbon production assembly of  claim 12  further comprising a packer forming a seal between the dual-walled coiled tubing assembly and the wellbore and wherein:
 an annulus is defined between the dual-walled coiled tubing assembly and the wellbore; and 
 production fluid is flowed through the dual-walled coiled tubing assembly. 
 
     
     
         23 . The hydrocarbon production assembly of  claim 12  further comprising a packer forming a seal between the dual-walled coiled tubing assembly and the wellbore and wherein:
 an annulus is defined between the dual-walled coiled tubing assembly and the wellbore; and 
 production fluid is flowed through the annulus and the dual-walled coiled tubing assembly. 
 
     
     
         24 . The dual-walled coiled tubing assembly of  claim 12  further comprising separate first and second fluid injection paths defined within the outer coiled tubing string. 
     
     
         25 . The dual-walled coiled tubing assembly of  claim 12  wherein at least one of the inner and outer coiled tubing strings are formed of corrosion-resistant material and one of the inner and outer coiled tubing strings is composed of a grade of metal that is different from that of the other of the inner and outer coiled tubing strings. 
     
     
         26 . The dual-walled coiled tubing assembly of  claim 12  wherein a metal-to-metal lubricant is used during manufacture of the dual-walled coiled tubing assembly.