# US 10,119,366 B2 · Insulated conductors formed using a final reduction step after heat treating > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,119,366 B2 - Document ID: US10119366B2 - Status: Granted - Kind: B2 - Application number: 14/675,024 - Filed: 2015-03-31 - Published: 2015-10-08 - Granted: 2018-11-06 - Earliest claimed: 2014-04-04 - Applicants: Shell Oil Company - Inventors: Justin Michael Noel; Robert Anthony Shaffer; Edward Everett De St. Remey; Dhruv Arora; Trevor Alexander Craney; Gilbert Luis Herrera; Robert Guy Harley; David Booth Burns; Alexei Tcherniak; Stephen Taylor Thompson; Albert Destrehan Harvey; Jonathan Clay Barnett - Web page: https://patentgrep.com/patent/US10119366B2 ## CPC - E21B 36/04: using electrical heaters - H05B 3/56: Heating cables - H05B 6/108: {for heating a fluid} - H05B 2203/017: Manufacturing methods or apparatus for heaters - H05B 2206/023: using the curie point of the material in which heating current is being generated to control the heating temperature - H05B 2214/03: Heating of hydrocarbons - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract An insulated electrical conductor (MI cable) may include an inner electrical conductor, an electrical insulator at least partially surrounding the electrical conductor, and an outer electrical conductor at least partially surrounding the electrical insulator. The insulated electrical conductor may have a substantially continuous length of at least about 100 m. The insulated electrical conductor may have an initial breakdown voltage, over a substantially continuous length of at least about 100 m, of at least about 60 volts per mil of the electrical insulator thickness (about 2400 volts per mm of the electrical insulator thickness) at about 1300° F. (about 700° C.) and about 60 Hz. The insulated electrical conductor may be capable of being coiled around a radius of about 100 times a diameter of the insulated electrical conductor. The outer electrical conductor may have a yield strength based on a 0.2% offset of about 100 kpsi. ## Claims ### Claim 1 An insulated electrical conductor, comprising: an inner electrical conductor; an electrical insulator at least partially surrounding the electrical conductor, the electrical insulator comprising mineral insulation; and an outer electrical conductor at least partially surrounding the electrical insulator; wherein the insulated electrical conductor comprises a substantially continuous length of from 100 m to 3000 m; and wherein the insulated electrical conductor comprises an initial breakdown voltage, over the substantially continuous length of from 100 m to 3000 m, of from 2400 to 4750 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz. ### Claim 2 (depends on 1) The conductor of claim 1, wherein the substantially continuous length of the insulated electrical conductor comprises a length without any splice. ### Claim 3 (depends on 1) The conductor of claim 1, wherein the outer electrical conductor comprises a continuous seam weld along the substantially continuous length of the insulated electrical conductor. ### Claim 4 (depends on 1) The conductor of claim 1, wherein the insulated electrical conductor has been formed using alternating cold working/heat treating steps on the insulated electrical conductor with a final cold working step that reduces a cross-sectional area of the insulated electrical conductor to a final cross-sectional area of the insulated electrical conductor. ### Claim 5 (depends on 4) The conductor of claim 4, wherein the final cold working step comprises reducing the cross-sectional area of the insulated electrical conductor by at most 20% to the final cross-sectional area. ### Claim 6 (depends on 4) The conductor of claim 4, wherein the insulated electrical conductor has been heat treated at a temperature of from about 760° C. to about 1050° C. ### Claim 7 (depends on 1) The conductor of claim 1, wherein the insulated conductor has not been heat treated after a final compaction of the electrical insulator. ### Claim 8 (depends on 1) The conductor of claim 1, wherein the electrical insulator comprises a plurality of magnesium oxide blocks. ### Claim 9 (depends on 1) The conductor of claim 1, wherein the insulated electrical conductor comprises an initial breakdown voltage of at least about 4000 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz. ### Claim 10 (depends on 1) The conductor of claim 1, wherein the insulated electrical conductor comprises a substantially continuous length of at least about 500 m. ### Claim 11 (depends on 1) The conductor of claim 1, wherein the electrical insulator is at least partially compacted. ### Claim 12 (depends on 1) The conductor of claim 1, wherein the outer electrical conductor is in an at least partially cold worked state. ### Claim 13 (depends on 1) The conductor of claim 1, wherein the insulated electrical conductor is configured to be placed in an opening in a subsurface formation and provide a heat output of from about 100 to about 500 W/m to the subsurface formation. ### Claim 14 (depends on 13) The conductor of claim 13, wherein the insulated electrical conductor comprises sufficient mechanical integrity for use in heating the subsurface formation. ### Claim 15 (depends on 1) The conductor of claim 1, wherein the insulated electrical conductor is capable of withstanding a lightning impulse level of 60 kV BIL (Basic Impulse Level) as defined in IEEE-Std 4. ### Claim 16 An insulated electrical conductor, comprising: an inner electrical conductor; an electrical insulator at least partially surrounding the electrical conductor, the electrical insulator comprising mineral insulation; and an outer electrical conductor at least partially surrounding the electrical insulator; wherein the insulated electrical conductor is capable of being coiled around a radius of from about 50 to about 100 times a diameter of the insulated electrical conductor; and wherein the insulated electrical conductor comprises an initial breakdown voltage, over a substantially continuous length of from about 100 m to about 3000 m, of from about 2400 to about 4750 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz. ### Claim 17 (depends on 16) The conductor of claim 16, wherein the insulated electrical conductor is capable of being coiled around a radius of about 75 times a diameter of the insulated electrical conductor. ### Claim 18 (depends on 16) The conductor of claim 16, wherein the outer electrical conductor comprises a continuous seam weld along the substantially continuous length of the insulated electrical conductor. ### Claim 19 (depends on 16) The conductor of claim 16, wherein the insulated electrical conductor comprises a substantially continuous length of from about 100 m to about 3000 m. ### Claim 20 (depends on 16) The conductor of claim 16, wherein the outer electrical conductor is in an at least partially cold worked state. ### Claim 21 (depends on 16) The conductor of claim 16, wherein the outer electrical conductor has a yield strength based on a 0.2% offset of about 100 kpsi. ### Claim 22 (depends on 16) The conductor of claim 16, wherein the outer electrical conductor includes a heat treated and cold worked alloy material with a yield strength based on a 0.2% offset of from about 150% to about 400% of the yield strength of the alloy material in its natural state. ### Claim 23 An insulated electrical conductor, comprising: an inner electrical conductor; an electrical insulator at least partially surrounding the electrical conductor, the electrical insulator comprising mineral insulation; and an outer electrical conductor at least partially surrounding the electrical insulator, wherein the outer electrical conductor has a yield strength based on a 0.2% offset of about 120 kpsi; wherein the insulated electrical conductor comprises an initial breakdown voltage, over a substantially continuous length of from about 100 m to about 3000 m, of from about 2400 to about 4750 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz. ### Claim 24 (depends on 23) The conductor of claim 23, wherein the outer electrical conductor has a yield strength based on a 0.2% offset of about 100 kpsi. ### Claim 25 (depends on 23) The conductor of claim 23, wherein the outer electrical conductor has a yield strength based on a 0.2% offset of about 80 kpsi. ### Claim 26 (depends on 23) The conductor of claim 23, wherein the outer electrical conductor comprises a continuous seam weld along the substantially continuous length of the insulated electrical conductor. ### Claim 27 (depends on 23) The conductor of claim 23, wherein the insulated electrical conductor comprises a substantially continuous length of from about 100 m to about 3000 m. ### Claim 28 (depends on 23) The conductor of claim 23, wherein the outer electrical conductor is in an at least partially cold worked state. ### Claim 29 An insulated electrical conductor, comprising: an inner electrical conductor; an electrical insulator at least partially surrounding the electrical conductor, the electrical insulator comprising mineral insulation; and an outer electrical conductor at least partially surrounding the electrical insulator, wherein the outer electrical conductor includes a heat treated and cold worked alloy material with a yield strength based on a 0.2% offset of about 50% more than the yield strength of the alloy material in its natural state but at most about 400% of the yield strength of the alloy material in its natural state; wherein the insulated electrical conductor comprises an initial breakdown voltage, over a substantially continuous length of from about 100 m to about 3000 m, of from about 2400 to about 4750 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz. ### Claim 30 (depends on 29) The conductor of claim 29, wherein the natural state of the alloy material comprises a state of the alloy material before any cold working or heat treating of the alloy material. ### Claim 31 (depends on 29) The conductor of claim 29, wherein the outer electrical conductor has a yield strength based on a 0.2% offset of about 120 kpsi. ### Claim 32 (depends on 29) The conductor of claim 29, wherein the outer electrical conductor comprises a continuous seam weld along the substantially continuous length of the insulated electrical conductor. ### Claim 33 (depends on 29) The conductor of claim 29, wherein the insulated electrical conductor comprises a substantially continuous length of from about 100 m to about 3000 m. ### Claim 34 (depends on 29) The conductor of claim 29, wherein the outer electrical conductor is in an at least partially cold worked state. ### Claim 35 A continuous insulated electrical conductor, comprising: a continuous inner electrical conductor; a continuous electrical insulator at least partially surrounding the continuous electrical conductor, the electrical insulator comprising mineral insulation; and a continuous outer electrical conductor at least partially surrounding the continuous electrical insulator; wherein the insulated electrical conductor comprises an initial breakdown voltage, over a substantially continuous length of from about 100 m to about 3000 m, of from about 2400 to about 4750 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz; and wherein the continuous outer electrical conductor is in a selected partial cold worked state that is intermediate between a post heat treated state and a fully cold worked state. ### Claim 36 (depends on 35) The conductor of claim 35, wherein the continuous insulated electrical conductor comprises a substantially continuous length of from about 100 m to about 3000 m. ### Claim 37 (depends on 35) The conductor of claim 35, wherein the post heat treated state comprises a state after the continuous insulated electrical conductor has been heated to a temperature of from about 760° C. to about 1050° C. for a selected time. ### Claim 38 (depends on 35) The conductor of claim 35, wherein the fully cold worked state comprises a state after the continuous insulated electrical conductor has been cold worked to reduce a cross-sectional area of the continuous insulated electrical conductor by about 30%. ### Claim 39 (depends on 35) The conductor of claim 35, wherein the continuous insulated electrical conductor has been formed using alternating cold working/heat treating steps on the continuous insulated electrical conductor with a final cold working step that reduces a cross-sectional area of the continuous insulated electrical conductor to a cross-sectional area that is about 80% or greater of the cross-sectional area of the continuous insulated electrical conductor after the preceeding heat treating step. ### Claim 40 (depends on 35) The conductor of claim 35, wherein the continuous insulated electrical conductor has no splices along its length. ### Claim 41 (depends on 35) The conductor of claim 35, wherein the continuous outer electrical conductor comprises a continuous seam weld along the length of the insulated electrical conductor. ### Claim 42 (depends on 35) The conductor of claim 35, wherein the continuous insulated electrical conductor is configured to be placed in an opening in a subsurface formation and provide a heat output of from about 100 to about 500 W/m to the subsurface formation. ### Claim 43 A system for heating a subsurface formation, comprising: an insulated electrical conductor positioned in an opening in the subsurface formation, wherein the insulated electrical conductor comprises: an inner electrical conductor; an electrical insulator at least partially surrounding the electrical conductor, the electrical insulator comprising mineral insulation; and an outer electrical conductor at least partially surrounding the electrical insulator; wherein the insulated electrical conductor comprises a substantially continuous length of from about 100 m to about 3000 m; and wherein the insulated electrical conductor comprises an initial breakdown voltage, over the substantially continuous length of from about 100 m to about 3000 m, of from about 2400 to about 4750 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz. ### Claim 44 (depends on 43) The system of claim 43, wherein the insulated electrical conductor is capable of being coiled around a radius of from about 50 to about 100 times a diameter of the insulated electrical conductor. ### Claim 45 (depends on 43) The system of claim 43, wherein the outer electrical conductor has a yield strength based on a 0.2% offset of about 120 kpsi. ### Claim 46 (depends on 43) The system of claim 43, wherein the outer electrical conductor includes a heat treated and cold worked alloy material with a yield strength based on a 0.2% offset of about 50% more than the yield strength of the alloy material in its natural state but at most about 400% of the yield strength of the alloy material in its natural state. ### Claim 47 (depends on 43) The system of claim 43, wherein the insulated electrical conductor has no splices along its length. ### Claim 48 (depends on 43) The system of claim 43, wherein the outer electrical conductor comprises a continuous seam weld along the length of the insulated electrical conductor. ### Claim 49 (depends on 43) The system of claim 43, wherein the insulated electrical conductor is configured to provide a heat output of from about 100 to about 500 W/m to the subsurface formation. ### Claim 50 A system for heating, comprising: an insulated electrical conductor positioned in a tubular, wherein the insulated electrical conductor comprises: an inner electrical conductor; an electrical insulator at least partially surrounding the electrical conductor, the electrical insulator comprising mineral insulation; and an outer electrical conductor at least partially surrounding the electrical insulator; wherein the insulated electrical conductor comprises a substantially continuous length of from about 100 m to about 3000 m; and wherein the insulated electrical conductor comprises an initial breakdown voltage, over the substantially continuous length of from about 100 m to about 3000 m, of from about 2400 to about 4750 volts per mm of the electrical insulator thickness at about 700° C. and about 60 Hz. ### Claim 51 (depends on 50) The system of claim 50, wherein the insulated electrical conductor is configured to heat fluids inside the tubular. ### Claim 52 (depends on 50) The system of claim 50, wherein the insulated electrical conductor is capable of being coiled around a radius of from about 50 to about 100 times a diameter of the insulated electrical conductor. ### Claim 53 (depends on 50) The system of claim 50, wherein the outer electrical conductor has a yield strength based on a 0.2% offset of about 120 kpsi. ### Claim 54 (depends on 50) The system of claim 50, wherein the outer electrical conductor includes a heat treated and cold worked alloy material with a yield strength based on a 0.2% offset of about 50% more than the yield strength of the alloy material in its natural state but at most about 400% of the yield strength of the alloy material in its natural state. ### Claim 55 (depends on 50) The system of claim 50, wherein the insulated electrical conductor has no splices along its length. ### Claim 56 (depends on 50) The system of claim 50, wherein the outer electrical conductor comprises a continuous seam weld along the length of the insulated electrical conductor.