Systems and methods for cable deployment of downhole equipment
Systems and methods for cable deployment of downhole equipment, wherein the conductors of a power cable bear the load of the downhole equipment and jewelry, as well as the cable itself. The power cable includes a set of elongated conductors, an upper coupling and a lower coupling. The upper support coupling suspends each of the conductors from the support structure and electrically couples the conductors to a power source. The lower coupling suspends the downhole electrical equipment from the conductors and electrically couples the conductors to the downhole equipment. One embodiment uses 7075 T-6 aluminum conductors to provide a length of at least 10,000 feet, a yield stress of at least 50,000 psi and a resistance of less than 0.2 ohm/kf. The aluminum conductors are homogeneous and are non-reactive with hydrogen sulfide, so no lead sheathing is required.
1. A system for cable deployment of downhole equipment, the system comprising:
a support structure positioned at the surface of a well;
a piece of downhole electrical equipment; and
an elongated cable coupling the piece of downhole electrical equipment to the support structure;
wherein the elongated cable includes
a plurality of weight-bearing conductors,
one or more layers of insulating or protective material surrounding the weight-bearing conductors,
an upper support coupling connected to an upper end of each of the weight-bearing conductors, wherein the upper support coupling suspends each of the weight-bearing conductors from the support structure, and
a lower equipment coupling connected to a lower end of each of the weight-bearing conductors, wherein the lower equipment coupling suspends the piece of downhole electrical equipment from the plurality of weight-bearing conductors,
wherein the plurality of weight-bearing conductors are electrically coupled to the piece of downhole electrical equipment, wherein power is transmitted through the plurality of weight-bearing conductors to the piece of downhole electrical equipment, and wherein substantially all of the weight of the piece of downhole electrical equipment is transferred from the lower equipment coupling only through the plurality of weight-bearing conductors to the upper support coupling;
wherein the weight-bearing conductors comprise an aluminum alloy.
2. The system of claim 1 , wherein the cable has a length between the upper end and the lower end of at least 10,000 feet.
3. The system of claim 2 , wherein each of the plurality of weight-bearing conductors has an outer diameter of at least 0.5 inches, wherein each of the plurality of weight-bearing conductors is surrounded by a layer of electrical insulation, wherein each of the plurality of the insulated weight-bearing conductors is encased in an elastomeric jacket, and wherein the elastomeric jacket is wrapped in a protective armor layer.
4. The system of claim 1 , wherein the weight-bearing conductors comprise a single, homogeneous metal.
5. The system of claim 1 , wherein the aluminum alloy comprises 7075 T-6 aluminum.
6. The system of claim 1 , wherein the weight-bearing conductors comprise a material having a yield stress of at least 50,000 psi and a resistance of no more than 0.2 ohm/kf at 68 F.
7. The system of claim 1 , wherein the cable does not have a lead sheath.
8. The system of claim 1 , wherein the weight-bearing conductors are non-reactive with hydrogen sulfide.
9. The system of claim 1 , wherein the piece of downhole electrical equipment comprises an electric submersible pump.
10. An electrical power cable for deploying downhole equipment, the cable comprising;
a plurality of elongated weight-bearing conductors, wherein each of the plurality of weight-bearing conductors has an upper end and a lower end;
one or more layers of insulating or protective material surrounding the weight-bearing conductors;
an upper coupling secured to the upper end of each of the plurality of weight-bearing conductors, wherein the upper coupling is configured to be connected to a support structure at the surface of a well, and wherein the upper end of each of the plurality of weight-bearing conductors is configured to be electrically coupled to a power source; and
a lower coupling secured to the lower end of each of the plurality of weight-bearing conductors, wherein the lower coupling is configured to be connected to a piece of downhole equipment, thereby electrically coupling the lower end of each of the plurality of weight-bearing conductors to the piece of downhole equipment;
wherein the plurality of weight-bearing conductors convey electrical power from the power source to the piece of downhole equipment and wherein substantially all of the weight of the piece of downhole equipment is transferred only through the weight-bearing conductors to the support structure at the surface of the well;
wherein the weight-bearing conductors comprise an aluminum alloy.
11. The electrical power cable of claim 10 , wherein the cable has a length between the upper end and the lower end of at least 10,000 feet.
12. The electrical power cable of claim 11 , wherein each of the plurality of weight-bearing conductors has an outer diameter of at least 0.5 inches, wherein each of the plurality of weight-bearing conductors is surrounded by a layer of electrical insulation, wherein each of the plurality of the insulated weight-bearing conductors is encased in an elastomeric jacket, and wherein the elastomeric jacket is wrapped in a protective armor layer.
13. The electrical power cable of claim 10 , wherein the weight-bearing conductors comprise a single, homogeneous metal.
14. The electrical power cable of claim 10 , wherein the aluminum alloy comprises 7075 T-6 aluminum.
15. The electrical power cable of claim 10 , wherein the weight-bearing conductors comprise a material having a yield stress of at least 50,000 psi and a resistance of no more than 0.2 ohm/kf at 68 F.
16. The electrical power cable of claim 10 , wherein the cable does not have a lead sheath.
17. The electrical power cable of claim 10 , wherein the weight-bearing conductors are non-reactive with hydrogen sulfide.
18. A method for cable deployment of downhole equipment, the method comprising:
providing a power cable that includes a plurality of weight-bearing electrical conductors and one or more layers of insulating or protective material surrounding the weight-bearing electrical conductors, wherein the weight-bearing conductors comprise an aluminum alloy;
electrically and mechanically coupling a piece of downhole equipment to the weight-bearing electrical conductors at a lower end of the power cable;
suspending the piece of downhole equipment from one or more of the plurality of weight-bearing electrical conductors; and
securing the plurality of weight-bearing electrical conductors at an upper end of the power cable to a support structure at the surface of a well, wherein at least 90 percent of the weight of the downhole equipment is transferred only through the plurality of weight-bearing electrical conductors to the support structure.
19. The method of claim 18 , wherein each of the plurality of weight-bearing electrical conductors is non-reactive with hydrogen sulfide, has a yield stress of at least 50,000 psi, and has a resistance of no more than 0.2 ohm/kf at 68 F.
20. The method of claim 19 , wherein each of the plurality of weight-bearing electrical conductors has an outer diameter of at least 0.5 inches, wherein each of the plurality of weight-bearing conductors is surrounded by a layer of electrical insulation, wherein each of the plurality of the insulated weight-bearing conductors is encased in an elastomeric jacket, and wherein the elastomeric jacket is wrapped in a protective armor layer.