FIRE RESISTANT FIBER OPTICAL CABLE WITH LARGE FIBER NUMBER Russian patent published in 2021 - IPC G02B6/44 

FIELD: fire security.

SUBSTANCE: invention relates to the field of optical cables suitable for operation during and after a fire. In particular, the present invention relates to a flame retardant optical fiber cable having a large number of fibers. The claimed flame retardant fiber optic cable with a large number of fibers contains: a core containing a central carrier and a plurality of buffer tubes disposed around the said central carrier, each buffer tube contains a plurality of optical fibers; a mica layer placed around the core; a layer of glass yarn surrounding and in direct contact with the mica layer; an inner shell surrounding and in direct contact with the glass yarn layer; metal armor surrounding the inner shell; and an outer shell surrounding and in direct contact with the metal armor, wherein the central support comprises a hydroxide-containing flame-retardant polymer material, and wherein the buffer tubes comprise a hydrophobic filling material containing silicone gel, said silicone gel having a dropping point, equal to at least 200°C.

EFFECT: creation of a fiber-optic cable with a large number of fibers, adapted to maintain its characteristics not only during a fire, but also for a predetermined period of time after the fire is extinguished, and an additional reduction in optical fiber breakage after a fire.

12 cl, 1 dwg