JPH1147297A - Fireproof sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and surely prevent an electric wire and a cable from burning and spreading as a fire spreading medium during firing regardless being newly constructed or existing. SOLUTION: This fireproof sheet 3 is prepd. by laminating integrally each at least one sheet of a rubber sheet 1 with an oxygen index of at least 28, the amt. of hydrogenhalide gas generation during burning of at least 0-350 mg/g and a thickness of 0.1-3 mm and a metal sheet 2 consisting of a metal with a m.p. of at least 600 deg.C and with a thickness of 15-200 μm. A wire and a cable are covered and surrounded with this fireproof sheet 3. In addition, heat dissipation properties may be improved by making radiation factors of the surfaces of the rubber sheet 1 and the metal sheet 2 at least 0.5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is intended to prevent the spread of electric wires, cables, or gas pipes which have been subjected to corrosion protection by resin in a fire in the event of a fire. The present invention relates to a fire protection sheet to be used.

[0002]

2. Description of the Related Art Conventionally, there is a risk that electric wires and cables laid by a cable rack or the like in a cave or a pipe space of a building will be burned in the event of a fire, and this will become a medium for spreading the fire and spread the fire. It is pointed out that there is. For this reason, the method of making these electric wires and cables themselves flame-retardant, providing a fire barrier in the cable penetration portion, or applying an inorganic paint for preventing fire spread to the electric wires and cables has been adopted. However, these measures are costly,
Both have advantages and disadvantages in terms of workability, fire spread prevention effect, etc., and it is particularly difficult to apply it to existing wires and cables, or even if it is applied, it is not possible to reliably prevent fire spread There was a point.

[0003]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to make it possible to simply and reliably prevent electric wires and cables from burning in the event of a fire and becoming a fire spread medium, regardless of whether they are new or existing. It is in.

[0004]

The object of the present invention is that the oxygen index is 28 or more and the amount of hydrogen halide gas generated is 0 to 350.
Using a fire sheet in which at least one rubber sheet having a thickness of 0.1 to 3 mm, which is mg / g, and a metal sheet having a thickness of 15 to 200 μm are laminated, and covering the wires and cables with the fire sheet. Is solved by Further, the metal sheet and the rubber sheet of the fireproof sheet may be exposed on the front surface and the back surface, and the radiation coefficient of each surface of these sheets may be 0.5 or more.
Further, as the admixture constituting the rubber sheet of the fire prevention sheet, a polyolefin admixture or a polychloroprene admixture is preferable.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
FIG. 1 shows an example of a fire protection sheet of the present invention. In the drawing, reference numeral 1 denotes a rubber sheet. The rubber sheet 1 is laminated and integrated with a metal sheet 2 to form a fire protection sheet 3. The rubber mixture constituting the rubber sheet 1 has a high flame retardancy having an oxygen index (OI) of 28 or more, preferably 30 or more, and contains 0 to 350 mg / g of a hydrogen halide gas such as hydrogen chloride during combustion. Preferably, it is composed of an admixture having a property of generating from 0 to less than 80 mg / g.

[0006] The oxygen index here is based on JIS K7201.
And the amount of hydrogen halide gas generated during combustion is based on the measurement method specified in IEC-754-1. If the oxygen index is less than 28, the fire protection sheet 3 itself tends to burn, and the effect of preventing fire spread becomes insufficient. Further, even if the amount of hydrogen halide gas generation exceeds 350 mg / g, the effect of preventing fire spread will no longer increase, and moreover, a large amount of hydrogen halide gas will be generated, which is inconvenient. The thickness of the rubber sheet 1 is from 0.1 to 3 mm, preferably from 0.5 to 3 mm.
If it exceeds m, the sheet itself becomes heavy, and the handleability is poor.

[0007] The rubber mixture constituting the rubber sheet 1 includes:
There are two types that generate hydrogen halide gas during combustion and those that do not generate hydrogen halide gas. Examples of generating hydrogen halide gas include polychloroprene, chlorinated polyethylene, and chlorosulfonated polyethylene. Examples include halogenated rubber-based admixtures and admixtures in which halogen-based flame retardants are blended with non-halogen-based rubbers such as nitrile rubbers, butyl rubbers, ethylene propylene rubbers, and natural rubbers. This type of admixture generates hydrogen halide gas upon combustion. Non-halogen rubbers, such as butyl rubber, ethylene propylene rubber, and natural rubber, are blended with a large amount of water-containing inorganic compounds such as aluminum hydroxide and magnesium hydroxide as non-halogen flame retardants. What was done.

Among these admixtures, the rubber admixture which generates hydrogen halide gas during combustion is preferably a polychloroprene admixture. For example, 100 parts by weight of chloropyrene rubber and 10 parts by weight of magnesium hydroxide are used. 2
00 parts by weight, 5 to 50 parts by weight of antimony oxide, 5 to 50 parts by weight of phosphate frit, 0.1 to 5 parts by weight of antioxidant, 10 to 100 parts by weight of inorganic filler, 5 to 50 parts by weight of carbon black, etc. Admixed with rubber sheet 1
It is most preferable because it can be carbonized and solidified after burning, and can surround the wires and cables and block the air even after burning. The rubber admixture that does not generate hydrogen halide gas during combustion is preferably a polyolefin-based admixture. For example, 100 parts by weight of ethylene propylene rubber (EPM) or ethylene propylene diene rubber (EPDM) is mixed with 50 parts by weight of magnesium hydroxide. -300 parts by weight, phosphate frit 5-50 parts by weight, antioxidant 0.1-5 parts by weight, inorganic filler 10-100 parts by weight, carbon black 5-50 parts by weight is preferable. This admixture also has the property of being carbonized and solidified after combustion.

The metal sheet 2 has a melting point of 600, such as iron, steel, copper, copper alloy, aluminum, and aluminum alloy.
A metal foil having a thickness of 15 to 200 μC or higher.
m. A metal having a melting point of less than 600 ° C. is unsuitable because it melts in a fire and cannot maintain its shape. If the thickness is less than 15 μm, the effect of the metal sheet 2 cannot be obtained, and if it exceeds 200 μm, the flexibility of the fire protection sheet 3 is reduced, which causes inconvenience in handling.

The lamination and integration of the rubber sheet 1 and the metal sheet 2 can be easily performed by using an adhesive such as a rubber adhesive. The dimensions of the fire protection sheet 3 are not particularly limited, but usually a roll-shaped sheet having a width of 40 to 100 cm and a length of 10 to 20 m is preferable from the viewpoint of productivity and workability.

Such a fireproof sheet has the following effect of preventing fire spread. That is, IEEE38
An electric wire or cable having a flammability enough to burn down in the cable vertical combustion test specified in 3 is used as a sample, and the electric wire or cable to be used as a sample is mounted in a Steiner tunnel horizontal combustion furnace shown in FIG. The Steiner Tunnel Horizontal Combustion Furnace is specified in ASTM E84-91 and is intended for combustion in a cave, etc., and can perform the strictest cable combustion test.

The fireproof sheet 3 is intermittently connected or extended over a length of about 4.5 m at a substantially central portion of the 7.32 m-long electric wires and cables 4, 4... Attached to the tray 5 of the Steiner tunnel horizontal combustion furnace. It is necessary to have an effect of preventing fire spread beyond a level at which the wires, cables 4, 4. Calorific value of burner 6: 150,000 BTU / hour Burning time of burner 6: 40 minutes Ventilation rate in furnace: 0.6 m / sec Tray 5 dimensions: width 285 mm, length 7.32 m

The fireproof sheet also has the effect of preventing fire from spreading out the wires and cables in the following vertical combustion test. That is, in the cable vertical combustion test of IEC332-3 performed using the combustion test apparatus as shown in FIG. 3, the combustion which burns completely under the condition of category C with a burner burning time of 20 minutes and a calorific value of 70000 BTU / hour. Are used as a sample, a plurality of these wires, cables 4, 4... Are mounted on a ladder 7 of the above-mentioned combustion test apparatus, and burners 6 to 30 are attached.
cm, the fire protection sheet 3 is intermittently wound as shown in the figure, or continuously wound up to the top, and in this state, the condition of category A, burner burning time 40 minutes, burner Heat generation 70000B
A combustion test is performed at TU / hour, and the wire, cable 4, 4.

As described in the second aspect of the present invention, the fire protection sheet of the present invention is arranged, laminated, and laminated so that the rubber sheet 1 and the metal sheet 2 are exposed on the front surface and the back surface of the fire protection sheet 3, respectively. Each of the surfaces exposed to the outside of the metal sheet 2 and the rubber sheet 1 is set to have a radiation coefficient (ratio of heat dissipation by radiation to a black body) of 0.5 or more to facilitate heat radiation. You can also. This metal sheet 2
In order to make the radiation coefficient of the surface of 0.5 or more, a method of applying dark paint such as black, gray, black brown, a method of attaching a similar dark plastic film, a similar dark rubber And a method of roughening the surface of the metal sheet 2 by sandblasting or the like. Further, the radiation coefficient of the surface of the rubber sheet 1 is set to 0.5
In order to achieve the above, it is most practical to use a mixture of a black colorant such as carbon black as the rubber mixture constituting the rubber sheet 1. May be used.

Next, a method of using such a fireproof sheet will be described. First, there is a method in which the fire protection sheet 3 is directly wound around the electric wire or cable itself. At this time, the fire protection sheet 3
The rubber sheet 1 is wound inside and the metal sheet 2 is wound outside. The electric wires and cables may be a single wire or a group of a plurality of electric wires and cables. In addition, the fire protection sheet 3 extends over the entire length of the wire or cable along the extension direction.
May be wound, or may be wound intermittently. When winding intermittently, set the length of the wound part to 0.5
By setting it to m or more, preferably 1 m or more, it is possible to sufficiently prevent the spread of fire.

As for the existing electric wires and cables housed in the cable rack installed in the cave or in the pipe space of the building, as shown in FIG. 4, the electric wires and cables 4, 4. There is a method in which the entire cable rack 8 is wound around the fire protection sheet 3. In this case as well, as in the case of the above, it is also possible to intermittently wind in the extension direction, and the length of the wound portion is 0.1 mm.
5 m to 1 m or more is sufficient. At both ends or at the center of the wrapped portion of the fire protection sheet 3, the fire protection sheet 3 and the electric wire,
Oxygen index 2 to close the gap between cables 4, 4 ...
It is also effective to fill with 8 or more flame-retardant putties and seal it.

A single wrap of the fire protection sheet 3 is sufficient, but a double or multiple wrap may be used. It is sufficient to fix the fire protection sheet 3 by a method such as fastening with a binding wire or tape. When the fire protection sheet 3 is wrapped around the electric wire, the cables 4, 4... Or the cable rack 8 accommodating them, the wrap width of the sheet 3 is 3.
cm or more. Furthermore, fire prevention sheet 3
, Or the cable rack 8 in a vertically attached state.

The fire protection sheet 3 having such a configuration is a laminated sheet of the rubber sheet 1 having high flame retardancy and the non-flammable metal sheet 2, so that it is difficult to burn in the event of a fire. The pyrolysis gas generated when the electric wires and cables 4, 4 ... wrapped inside are heated is sealed and not released to the outside, and the inflow of air from the outside is shut off. The suffocation state or the lack of oxygen occurs. In the case where a hydrogen halide gas is generated from the rubber sheet 1 during combustion, the hydrogen halide gas fills the inside, and the state of oxygen deficiency is further promoted.

Further, when the rubber sheet 1 is carbonized and solidified at the time of combustion, the sealed state is maintained even after the rubber sheet 1 is burned, the inflow of air is prevented, and the solidified material functions as a heat insulating material. Cut off heat from outside. Further, the burned material of the rubber sheet 1 adheres to the metal sheet 2, and the burned material is prevented from dropping onto the wires, cables 4, 4,.

Due to the complex and synergistic action of these various functions, the electric wires and cables 4 wrapped in the fire protection sheet 3
4 are prevented from burning and do not become a fire spread medium, and the above-described advanced fire spread prevention effect is exhibited. When the radiation coefficient of each surface of the rubber sheet 1 and the metal sheet 2 is set to 0.5 or more, the heat generated by the power supply to the electric wires and the cables in the normal state is the inside of the space surrounded by the fire protection sheet 3. It is efficiently radiated to the outside without being confined, the temperature rise of electric wires and cables themselves is suppressed, and the allowable current does not decrease.

Furthermore, if the rubber sheet 1 is made of an admixture that does not generate hydrogen halide gas, no harmful hydrogen halide gas is generated during combustion, so that there is no danger due to this gas and it is safe. Also, the workability of winding around the electric wires and cables 4, 4... Is good and the construction is easy. When changing the wiring route of the electric wires and cables 4, 4. It can be reused.

The fire prevention sheet of the present invention is not limited to the example shown in FIG. 1, but may be a laminate in which one or more rubber sheets 1 and one or more metal sheets 2 are combined. When a rubber sheet having a radiation coefficient of 0.5 or more is used, a laminated structure in which the metal sheet 2 is sandwiched between the rubber sheets 1 may be employed. Further, a glass cloth can be embedded in the rubber sheet 1 as required. As the glass cloth, a chopped strand mat, a roving cloth, a yarn cloth or the like made of ordinary glass fiber is used, and the abundance of the glass cloth in the rubber sheet 1 is about 2 to 20% by volume ratio.

Hereinafter, specific examples will be described. (Experimental Example 1) The rubber sheet 1 and the metal sheet 2 shown in Tables 1 and 2 were laminated and integrated one by one to produce 15 types of fireproof sheets 3 having the structure shown in FIG. On the other hand, the width of the Steiner tunnel horizontal combustion furnace shown in FIG.
600V CV 3C x 38mm on a 32m tray 5
^{The two} cables 4, 4... Were closely arranged in two rows of ten cables. It has been previously confirmed that this cable 4 is completely burned in a cable vertical burning test of IEEE 383. The length of the cable 4 was 7.32 m, and the fire protection sheet 3 was continuously wound by wrap winding over a length of about 4.5 m from a position 1.6 m from the end of the cable 4 on the burner 6 side.

Then, a combustion test was carried out under the conditions of a calorific value of the burner 6 of 150,000 BTU / hour, a burning time of 40 minutes, and a ventilation speed in the furnace of 0.6 m / sec. The length of the flame, the presence or absence of ignition of the exposed portion of the cable 4 on the exit side, and the presence or absence of damage to the fire protection sheet 3 after completion were observed. In addition, the workability of winding the fire protection sheet 3 was evaluated as good if the fire protection sheet 3 was not easy to wind because of heavy or hard, etc., and if not good. The results are shown in Tables 1 and 2. In addition, Pb and Sn of the metal sheet in Table 2 have a melting point of less than 600 ° C.

[0025]

[Table 1]

[0026]

[Table 2]

From the results shown in Tables 1 and 2, it was found that the fireproof sheet of the present invention exhibited an excellent effect of preventing fire spread, and also had good workability of winding the wire and cable.

(Experimental Example 2) A 1.5 mm thick rubber sheet (sample A) made of a chloroprene rubber-based admixture blended with carbon black, and the rubber sheet having a thickness of 0.1 mm was used.
A black epoxy resin paint is applied to both surfaces of a laminated sheet (sample B) in which a metal sheet of a 2 mm stainless steel foil is bonded and a stainless steel foil of the laminated sheet, and the radiation coefficient of both surfaces is reduced to 0. .85 (sample C). These three sample sheets (A ~
In C), a 600 V CV 3C × 38 mm ² cable is wrapped around a cable bundle in which 10 cables are closely arranged and arranged in a two-stage stack, and a current of 70 A is supplied at an ambient temperature of 40 ° C. to wrap the sheet. The change in the temperature of the internal cable conductor was measured.

When four hours have passed since the start of energization, the conductor surrounding the sheet of sample A had a conductor temperature of about 91 ° C.
, And about 10 sheets surround the sheet of sample B.
5 ° C., and about 92 ° C. for the sheet of sample C. From this result, the fire sheet of Sample C has good heat dissipation from the inside of the sheet.
Even when the cable is surrounded, the heat generated by electricity is not trapped in the space inside the sheet, it is efficiently radiated to the outside, the rise in conductor temperature is suppressed, and the allowable current of wires and cables is reduced by surrounding the fireproof sheet It turned out to be subtle.

[0030]

As described above, in the fire prevention sheet of the present invention, by wrapping it around an electric wire or cable, the electric wire or cable is prevented from burning, and an excellent fire spread prevention effect is exhibited. In addition, it is extremely simple to wind around electric wires and cables, and can be easily removed and reused. Furthermore, in normal times, the allowable current of the electric wires and cables surrounded by the fire prevention sheet does not decrease.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing an example of a fire protection sheet of the present invention.

FIG. 2 is a schematic configuration diagram showing a combustion test using a Steiner tunnel horizontal combustion furnace according to the present invention.

FIG. 3 is a schematic configuration diagram showing a cable vertical combustion test in the present invention.

FIG. 4 is a configuration diagram showing an example of a use state of the fire prevention sheet of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Rubber sheet, 2 ... Metal sheet, 3 ... Fireproof sheet, 4
… Wires and cables

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Katsuji Takahara 1-5-1, Kiba, Koto-ku, Tokyo Inside Fujikura Co., Ltd. (72) Inventor Eishin Mochizuki 9-1 Futaba-cho, Numazu-shi, Shizuoka Co., Ltd. Fujikura Numazu Plant (72) Inventor Keigo Teramoto 9-1 Futaba-cho, Numazu-shi, Shizuoka Prefecture Fujikura Numazu Plant (72) Inventor Hisashinobu Soejima 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Within the Technology Development Division (72) Inventor Yasuichi Hayashi 1 Kimitsu, Kimitsu City, Chiba Prefecture Inside Nippon Steel Corporation Kimitsu Works (72) Inventor Shigeru Kitagawa 1 Kimitsu, Kimitsu City, Chiba Prefecture Kimitsu Corporation Inside the steelworks

Claims (3)

[Claims] 1. A thickness of 0.1 to 3 having an oxygen index of 28 or more and a hydrogen halide gas generation amount of 0 to 350 mg / g.
A fire protection sheet obtained by laminating one or more rubber sheets each having a thickness of 15 mm and a metal sheet having a thickness of 15 to 200 μm. 2. A thickness of 0.1 to 3 having an oxygen index of 28 or more and a hydrogen halide gas generation amount of 0 to 350 mg / g.
a rubber sheet having a thickness of 15 mm to 200 μm and a metal sheet having a thickness of 15 to 200 μm, each of which is laminated with a rubber sheet on one surface and a metal sheet on the other surface. A fire protection sheet wherein the surface has an emission coefficient of 0.5 or more. 3. The fire prevention sheet according to claim 1, wherein the rubber mixture constituting the rubber sheet is a polyolefin mixture or a polychloroprene mixture.