AIR-PERMEABLE BOREHOLE FIBRE-OPTIC CABLE AND METHOD OF RESTORING OPERATIONAL CHARACTERISTICS THEREOF

摘要

FIELD: physics.;SUBSTANCE: cable has an outer protective tube, a fibre-optic tube, an annular cavity between the outer protective tube and the fibre-optic tube and two passages along the length of the fibre-optic cable. The fibre-optic tube contains optical fibres. The first passage forms a channel for flow of blowout gas and is meant for inlet of blowout gas into the fibre-optic cable. The second passage forms a channel for flow of blowout gas and is meant for returning blowout gas through the means of connecting the first and second passages on the cable in a second direction opposite the first direction. According to the method, operational characteristics of the fibre-optic cable are restored by removing gas diffusing through the optical fibres.;EFFECT: possibility of ventilating the cable in order to reduce hydrogen partial pressure near the optical fibre.;18 cl, 8 dwg