RU194789U1 - CABLE OPTICAL FIRE SAFE FIRE RESISTANT - Google Patents

Abstract

The utility model relates to cable technology, namely, to the construction of optical cables intended for indoor and outdoor installation on stationary objects with increased safety requirements, including fire protection systems, as well as other systems that must remain operational in a fire. The cable contains multimode or single-mode optical fibers placed freely in tubes of polymer material around a central power element, protected by internal fire a resistant sheath made of a material with an oxygen index of at least 50% and a specific heat of combustion, determined according to ISO 5660, not more than 35.2 MJ / m, partially filling the space between the tubes made of polybutylene terephthalate and acting as a barrier to moisture and thermal barrier, the inner shell is wrapped mica tape, a layer or layer of fiberglass or equivalent flexible fireproof filaments is applied, and an outer shell made of a fireproof halogen-free material with an oxygen index of at least 40% and specific heat of combustion as determined by ISO 5660, not more than 12 MJ / kg.Tehnichesky result - dymogazovydelenie low in burning or smoldering. 6 c.p. f-ly, 2 ill.

Description

The utility model relates to cable technology, namely, to the construction of optical cables intended for indoor and outdoor installation on stationary objects with increased safety requirements, including fire protection systems, as well as other systems that must remain operational in a fire.

Known optical fireproof cable

(RF patent for utility model No. RU 115513 U1, publ. in Bulletin No. 12 04/27/2012, RF patents for utility model No. RU 130415 U1 and RU 130416 U1, publ. in Bulletin No. 20 07/20/2013 ), containing optical fibers in a dense buffer coating - a multilayer protective coating of carbon and metal or carbon and polymer, laid in the core around a central strength element (CCE), a protective reinforcing heat-insulating layer (glass fibers or basalt threads, aramid threads, or in the form of a composition containing vermiculite / perlite) including water-swellable elements around the center and EPX core / shell below the inner and outer sheath of halogen free plastics material or silicone rubber, polyetherketone, fire resistant polyethylene or polypropylene.

This technical solution is close to that proposed in terms of dielectric design and functional purpose. A disadvantage of the known cables is the use of materials requiring the use of non-standard equipment used for the manufacture of optical cables - a multilayer protective coating of optical fibers made of carbon and metal or carbon and polymer. A well-known optical fireproof optical cable (RF patent for utility model No. RU 161295 U1, published in Bulletin No. 11 04/20/2016), containing optical fibers placed in tubes of polymer material around a central power element, located under the inner shell of the winding of water-swellable elements, armor and the outer shell, characterized in that the tubes, inner and outer shells are made of halogen-free material with a pH ≥ 4.3, the conductivity of an aqueous solution with adsorbed smoke and gas products no more than 10 μS / mm and a gas content of halogen acids in terms of HCl no more than 5.0 mg / g, while the inner and outer shells have an oxygen index of at least 27% and a specific heat of combustion, determined according to ISO 5660, not more than 16.5 MJ / kg. This technical solution is the closest to the proposed combination of features.

A disadvantage of the known cable is the use of materials that do not fully comply with the requirements of fire safety standards, as well as the presence of metal armor, which is more labor intensive in production and requires the organization of its grounding on the communication line to ensure the safety of maintenance personnel, and also leads to possible damage to the cable from lightning strikes.

The objective of the utility model is to create a cable with increased fire safety and reliability.

The technical result of the claimed utility model consists in low smoke and gas emission during combustion and decay.

The technical result is achieved in that in a cable containing multimode or single-mode optical fibers placed freely in tubes of a polymeric material around a central power element, protected by an internal flame-retardant sheath of a material with an oxygen index of at least 50% and specific heat of combustion, determined according to ISO 5660 not more than 35.2 mJ / m ^2, partially filling the space between the tubes made of polybutylene terephthalate and performing a barrier function for the thermal barrier and moisture exchange are more expensive aramid filaments, the inner shell is wrapped with mica tape, a layer or twisted of glass fibers or equivalent flexible fireproof threads is applied, and the outer shell is made of fireproof halogen-free material with an oxygen index of at least 40% and specific heat of combustion, determined according to ISO 5660, no more than 12 MJ / kg.

The cable may be provided with water swellable threads located in the tubes and / or between the tubes.

The central power element may be made of a fiberglass rod or an equivalent material that provides rigidity to the structure under bending under mechanical stress on the cable and under conditions of flame exposure of at least 750 ° C.

The central power element can be wrapped with a water blocking element in the form of a tape or thread.

As the material for the outer shell can be used: polymer halogen-free compositions of reduced fire hazard, for example, the brand Megolon S642 (company AlphaGary Corporation, USA) or other materials with similar characteristics.

The utility model is illustrated by drawings, in which sectional modifications of the cable are shown (Fig. 1 and Fig. 2).

The fireproof optical fireproof completely dielectric cable contains multimode or single-mode optical fibers 1 located in tubes 2 of polymer material around a central power element 3, an inner sheath 4, a mica tape 5, a layer of power elements 6, and an outer sheath 7 (Fig. 1).

If necessary, in the space between elements 2 and 3, 4 and 5, 5 and 6, as well as inside element 2, water-blocking elements 8 can be placed, and filling corners 9 can be added to the core composition (Fig. 2).

In the manufacture of cable using well-known materials manufactured on an industrial scale. The cable manufacturing technology includes the following operations: manufacturing a tube from a polymeric material 2 with free placement of optical fibers 1 (and, if necessary, a water blocking element), winding of the central power element 3 with a water blocking element 8 (if necessary), twisting of tubes 2 with optical fibers 1 in core around the central power element 3, the imposition of an internal flame retardant shell, partially filling the space between the tubes 4, winding or wrapping with a water blocking element 8 (if necessary location), applying a mica tape 5, wrapping or wrapping with a water blocking element 8 (if necessary), applying a layer or winding of glass fibers 6, applying an outer shell of a polymer fireproof halogen-free composition 7.

All operations are performed on standard equipment used for the manufacture of cables: extrusion lines, for example, LCE 110 (from SWISSCAB) or OEL 40 (from Maillefer Extrusion OY); twisting lines, for example, LCM 106 (made by SWISSCAB), OFC 70 (made by NEXTROM). Glass winding can be done, for example, on servers (GP 18) of line LCE 131 (made by SWISSCAB). The cable is made entirely of dielectric materials capable of working under conditions of flame exposure for 180 minutes and low smoke and gas emission during combustion and smoldering.

Characteristics of a non-flame retardant, flame retardant, fully dielectric cable:

working capacity under conditions of flame exposure - at least 180 min;

tensile strength - at least 2.7 kN;

operating temperature range - from minus 60 ° to 70 ° C;

cable outer diameter not more than 15 mm;

the attenuation coefficient of single-mode HF in the cable at operating wavelengths of 1.31 and 1.55 μm (upon receipt and delivery) of not more than 0.36 and 0.22 dB / km, respectively;

attenuation coefficient of multimode OB in the cable at a working wavelength of 1.3 μm (upon receipt and delivery) not more than 0.8 dB / km;

does not spread combustion during group installation (category A);

non-toxic (RoHS), does not emit corrosive substances;

low optical density of smoke during smoldering (burning) - not more than 30%.

Claims (7)

1. Optical flame-retardant fireproof optical cable completely dielectric, containing multimode or single-mode optical fibers placed in tubes of polymeric material around a central power element, an inner sheath, a mica tape, a layer or twisted glass fiber and an outer sheath, while the inner and outer sheaths are made of material with pH≥4.3, the conductivity of an aqueous solution with adsorbed products of smoke and gas evolution of not more than 10 μS / mm and the gas content of halogen acids in terms of HCl is not more than 5.0 μg / g, characterized in that the inner shell partially fills the space between the tubes made of polybutylene terephthalate, and the outer shell is made of a material with an oxygen index of at least 40% and a specific heat of combustion, determined according to ISO 5660, not more than 12 MJ / kg. 2. The cable according to claim 1, characterized in that it is equipped with water-swelling threads located in the tubes and / or between the tubes. 3. The cable according to claim 1, characterized in that the central power element is made of fiberglass rod. 4. Cable according to any one of paragraphs. 1-3, characterized in that the Central power element is wrapped with a water blocking element in the form of a tape or thread. 5. The cable according to claim 1, characterized in that the layer or winding of the thermal barrier threads is made of basalt or equivalent flexible fireproof threads. 6. The cable according to claim 1, characterized in that a longitudinally water-blocking element in the form of tape or threads is wound or laid under the outer sheath. 7. The cable according to claim 1, characterized in that it is equipped with filling cords located in contact with the tubes, made of a halogen-free material with an oxygen index of at least 27% and a specific heat of combustion determined according to ISO 5660 of not more than 17 MJ / kg.

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