INSULATED CONDUCTORS, FORMED USING THE STAGE OF FINAL DECREASE DIMENSION AFTER THERMAL TREATMENT Russian patent published in 2019 - IPC E21B43/24 E21B36/04 

FIELD: electrical engineering.

SUBSTANCE: invention relates to devices and methods used for heating of formations. Insulated electric conductor (MI cable) contains inner electric conductor, electric insulator, at least partially surrounding the electric conductor, and external electric conductor, at least partially surrounding electric insulator. Insulated electric conductor has practically continuous length of at least approximately 100 m. Insulated electric conductor at all said practically continuous length of at least approximately 100 m has breakdown beginning voltage of at least about 60 V per 1 mil thickness of electric insulator (about 2,400 V per 1 mm of thickness of electrical insulator) at approximately 1,300 °F (about 700 °C) and approximately 60 Hz. Insulated electric conductor can be coiled into a spiral with a radius of approximately 100 times larger than that of the insulated electric conductor. External electric conductor has yield point, based on 0.2 % displacement, approximately 700 MPa.

EFFECT: reduction or elimination of potential problems during production, assembly and/or installation of insulated conductors.

14 cl, 21 dwg