ARMOURED CABLE FOR DOWN HOLE ELECTRICAL SUBMERSIBLE PUMP
An ESP is suspended downhole on a cable comprising spirally wound copper clad steel conductors surrounded by nonmetallic sheathing wound in an opposite spiral direction, preferably in the direction of rotation of the rotor of the ESP. The torque exerted on the cable by the ESP is reacted against the conductors, relieving stress from the sheathing so that the cable may be light in weight yet support substantial loads.
1 . An assembly comprising an electrical submersible motor suspended on a self-supporting cable;
the cable comprising a group of insulated metallic conductors wound in a spiral configuration in a first direction of rotation and enclosed in a spirally wound casing;
wherein each of the conductors comprises a steel core clad with copper; and
wherein the casing comprises non-metallic fibres wound in a spiral configuration in a second direction of rotation opposite to the first direction.
2 . An assembly according to claim 1 , wherein the motor is a permanent magnet motor.
3 . An assembly according to claim 2 , wherein the motor drives a pump or compressor.
4 . An assembly according to claim 3 , wherein the pump or compressor is a rotary pump or compressor.
5 . An assembly according to claim 4 , wherein the motor comprises a rotor which rotates in use in the second direction.
6 . (canceled)
7 . An assembly according to claim 3 , wherein the motor comprises a rotor which rotates in use in the second direction.
8 . An assembly according to claim 2 , wherein the motor comprises a rotor which rotates in use in the second direction.
9 . An assembly according to claim 1 , wherein the motor drives a pump or compressor.
10 . An assembly according to claim 9 , wherein the pump or compressor is a rotary pump or compressor.
11 . An assembly according to claim 10 , wherein the motor comprises a rotor which rotates in use in the second direction.
12 . An assembly according to claim 9 , wherein the motor comprises a rotor which rotates in use in the second direction.
13 . An assembly according to claim 1 , wherein the motor comprises a rotor which rotates in use in the second direction.