JPH08131571A - Fire-proof sheet for inflammable cable - Google Patents

Abstract

PURPOSE: To improve fire resistance of a fire-proof sheet against a fire by laminating a fire-proof net on which a heat foaming coating to be foamed by heat in case of fire, and for forming a heat resistant insulating layer, a metallic foil and a flame retardant plastic foamed sheet on a heat resistant net main body in this order. CONSTITUTION: A fire-proof sheet 4 is formed by laminating a fire-proof net 1, an aluminum foil 5 and a flame retardant plastic foamed sheet 6 in this order and bonding respective layers by adhesives. The fire-proof net 1 is formed by coating a heat foaming coating 3 to be foamed by heat in a fire, and for forming a heat resistant insulating layer on a heat resistant net main body 2. The coating amount of the heat foaming coating 3 is about 600 to 800g/cm<2> . The thickness of the aluminum foil 5 is about 10 to 80μm. The flame retardant plastic foamed sheet 6 is made of a flame retardant polyethylene foamed sheet having the thickness of about 3 to 8mm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fireproof sheet used for fireproofing a flammable cable.

[0002]

2. Description of the Related Art Cables such as telecommunication cables, optical communication cables and electric power cables generally use a flammable material such as polyethylene for an insulator, a protective coating or a sheath, so that when a fire occurs, the longitudinal direction of There is a risk of spreading fire.

As a means for preventing the spread of flammable cables, it has recently been considered to wind a heat-foaming fireproof net 1 around the cable as shown in FIG.
The fireproof net 1 is made by applying a heat-foaming paint 3 to a net body 2 made of a fireproof material such as glass fiber thread by a dipping method or the like (manufactured and sold by Herberts GmbH in Germany). The heat-foaming paint foams 30 to 40 times when heated by a flame and carbonizes to form a good fireproof heat insulating layer.

[0004]

According to the result of the fire resistance test (850 ° C. × 20 minutes) specified in IEEE383, the fireproof net is wrapped around the flammable cable. It was confirmed that it was effective in preventing the spread of fire. However, simply by winding the fire protection net, the insulation resistance between the insulating cores will fall within 10 minutes after the flame is applied, and the cable functions (communication function, power transmission function, etc.) will not be maintained. It has been found.

In the case of fire protection of a cable, it is not enough to simply have a fire spread prevention effect, and it is required that the function of the cable can be maintained for a certain period of time (usually 20 minutes or more) while being exposed to the flame. To be done.

An object of the present invention is to provide a fireproof sheet for a flammable cable that solves the above problems.

[0007]

In order to achieve this object, the fireproof sheet for a flammable cable of the present invention comprises:
A fireproof net made by applying a heat-foamable paint that foams with the heat of a fire to form a fireproof heat insulating layer on the fireproof net body,
A metal foil and a flame-retardant plastic foam sheet are laminated in this order (Claim 1).
As the flame-retardant plastic foam sheet, a flame-retardant polyethylene foam sheet, a melamine resin foam sheet, or the like can be used.

When such a fireproof sheet is used, the internal cable is formed due to the formation of a fireproof heat insulating layer by foaming a fireproof net, the heat-reflecting property and flame blocking property of the metal foil, and the heat insulating property of the flame-retardant plastic foam sheet. It is possible to maintain the function as a cable for at least 20 minutes in a state where the temperature rise is suppressed and the flame hits.

The fireproof sheet for a flammable cable of the present invention may also be constructed by laminating the heat-foamable fireproof net, a metal foil, a flame-retardant plastic foam sheet, and a metal foil in this order. Yes (Claim 2). In this case, since the flame-retardant plastic foam sheet is sandwiched between the metal foils, the heat insulating property is further improved as compared with the fireproof sheet according to claim 1, and the effect of suppressing the temperature rise of the cable is increased.

The fireproof sheet for a flammable cable of the present invention also comprises, in this order, the heat-foamable fireproof net, a metal foil, a flame-retardant plastic foam sheet, and a composite sheet obtained by laminating a reinforcing sheet on the metal foil. It is also possible to adopt a constitution in which the layers are laminated by (Claim 3). Flame-retardant paper, glass cloth, or the like can be used as the reinforcing sheet. In this way, the same fire resistance as that of the fireproof sheet according to claim 2 can be obtained, and since the metal foil on the side in contact with the cable is reinforced by the reinforcing sheet, it will not be damaged when the cable is wound, etc. Is stable.

The fireproof sheet for a flammable cable of the present invention may also be constructed by laminating the heat-foamable fireproof net, a metal foil, a ceramic fiber blanket and a metal foil in this order (claim). Item 4). Even with such a configuration, it is possible to obtain the same fire resistance performance as that of the fire protection sheet of claim 1. Since the ceramic fiber blanket has a weak bonding force between the ceramic fibers, it is necessary to dispose metal foils on both sides to protect the blanket from being deformed.

The fireproof sheet for a flammable cable of the present invention is also formed by laminating the heat-foamable fireproof net, a metal foil, a ceramic fiber blanket, and a composite sheet obtained by laminating a reinforcing sheet on the metal foil in this order. It can also be configured (Claim 5). Flame-retardant paper, glass cloth, or the like can be used as the reinforcing sheet. In this way, the same fire resistance as that of the fire protection sheet of claim 4 is obtained, and since the metal foil on the side in contact with the cable is reinforced by the reinforcing sheet, it is not damaged when the cable is wound and the fire resistance is improved. Is stable and the protection of the ceramic fiber blanket is more reliable.

The flame-retardant plastic foam sheet used for the fireproof sheet of the present invention has a large number of parallel cuts (not cut in the thickness direction) on one or both sides in the same direction as the cable around which the fireproof sheet is wound. Should be formed. If such a notch is formed, it becomes easier to roll the fireproof sheet when the fireproof sheet is wound around the cable, and the winding work becomes easier.

[0014]

【Example】

[Embodiment 1] FIG. 1 shows an embodiment of the present invention. This fireproof sheet 4 is obtained by laminating a fireproof net 1, an aluminum foil 5, and a flame-retardant plastic foam sheet 6 in this order,
The layers are joined with an adhesive.

As shown in FIG. 6, the fireproof net 1 is formed by coating a fire resistant net body 2 with a heat-foamable paint 3 which foams by heat in a fire to form a fire resistant heat insulating layer. The space between the warp yarn and the weft yarn of the net body 3 is, for example, about 4 to 6 mm, and the coating amount of the heat-foaming paint 3 is, for example, 600 to 800 g.
/ M ² or so. Aluminum foil 5 has a thickness of 10-80
A material having a size of about μm is used. As the flame-retardant plastic foam sheet 6, a flame-retardant polyethylene foam sheet or a melamine resin foam sheet having a thickness of about 3 to 8 mm can be used.

Next, the results of conducting a fire resistance test by winding this fireproof sheet on a cable will be described. Fire resistance test is IEEE
According to the regulations of 383, a cable wound with a fireproof sheet is set on a vertical open tray, and the flame of a gas burner is applied for 20 minutes. The fireproof sheet used in the test is
Fire net 1 made by German Herberts company, thickness 50μ
m aluminum foil 5 and 5 mm thick flame-retardant polyethylene foam sheet 6 [Funagawa Ace (trade name) manufactured by Furukawa Electric Co., Ltd.] are laminated in this order, and each layer is joined with an adhesive. Is. The cable used for the test is a polyethylene insulation / polyethylene sheath communication cable (PE
C · H 0.9 × 200 pair). The fireproof sheet was wrapped around the cable with the fireproof net on the outside. A temperature detector was set between the fire protection sheet and the cable to check the temperature rise of the cable during the test. In addition, the insulation resistance of the insulated core wire pair inside the cable was measured to check the maintenance of the communication function.

In this fire resistance test, as soon as the burner flame hits, the heat-foamable paint of the fire-proof net foamed to form a fire-resistant heat-insulating layer, and while the burner flame hits (20 minutes).
Fires up due to the burning of organic materials in the heat-foamable paint, but 2
It was confirmed that when 0 minutes passed and the flame of the burner stopped, the flame was extinguished immediately and the spread of fire could be prevented. Further, it was found that the insulation resistance did not decrease at all even after 20 minutes had passed since the start of applying the flame, and the function as a cable could be sufficiently maintained. The maximum temperature of the cable was 150 ° C. The appearance of the cable sheath after the test was almost good, to the extent that the flame-retardant polyethylene foam sheet was attached.

[Embodiment 2] FIG. 2 shows an embodiment of the present invention. The fireproof sheet 4 is formed by laminating a fireproof net 1, an aluminum foil 5, a flame-retardant plastic foam sheet 6, and an aluminum foil 7 in this order, and joining each layer with an adhesive. The bottom aluminum foil 7 has a thickness of 10 to 8
Those having a size of about 0 μm are used. Other than that is the same as that of the first embodiment.

Next, the result of performing the same fire resistance test as in Example 1 by winding this fireproof sheet on a cable will be described. The following two types of fireproof sheets were used in the test. A fireproof net, an aluminum foil with a thickness of 50 μm, a flame-retardant polyethylene foam sheet with a thickness of 5 mm, and an aluminum foil with a thickness of 20 μm are laminated in this order, and each layer is joined with an adhesive.
Fireproof net, aluminum foil of thickness 50μm, thickness of 5m
A melamine resin foam sheet of m and an aluminum foil having a thickness of 20 μm are laminated in this order, and each layer is joined with an adhesive.

In this fire resistance test, it was confirmed that both of the fire protection sheets had the effect of preventing the spread of fire and that the insulation resistance did not decrease at all, and the appearance of the cable sheath after the test was also good. The maximum temperature of the cable was 116 ° C for the fireproof sheet and 130 ° C for the fireproof sheet.

[Embodiment 3] FIG. 3 shows an embodiment of the present invention. The fireproof sheet 4 includes a fireproof net 1, an aluminum foil 5, a flame-retardant plastic foam sheet 6, and a composite sheet 9 obtained by laminating a reinforcing glass cloth 8 on an aluminum foil 7 in this order, The layers are joined with an adhesive. Example 2 is the same as Example 2 except that the glass cloth 8 is laminated on the lowermost aluminum foil 7. Therefore, this fireproof sheet also has the same fire resistance as the fireproof sheet of Example 2.

When the composite sheet 9 in which the glass cloth 8 is laminated on the aluminum foil 7 is used as the lowermost layer, the aluminum foil 7 on the side in contact with the cable is reinforced by the glass cloth 8 and may be broken when wound around the cable. There is an advantage that it is easy to handle and the fire resistance is stable.

In the embodiment of FIG. 3, the composite sheet 9 is laminated on the flame-retardant plastic foam sheet 6 with the aluminum foil 7 on the outside, but the composite sheet 9 may be laminated with the aluminum foil 7 on the inside. Good. As the reinforcing sheet for the aluminum foil 7, flame-retardant paper or the like can be used instead of the glass cloth 8.

[Embodiment 4] FIG. 4 shows an embodiment of the present invention. The fireproof sheet 4 includes a fireproof net 1, an aluminum foil 5, a ceramic fiber blanket 10,
The aluminum foil 7 and the aluminum foil 7 are laminated in this order, and the respective layers are joined by an adhesive. However, since the ceramic fiber blanket 10 has a weak bonding strength between the ceramic fibers, the bonding strength with the aluminum foils 5 and 7 is also weak. The ceramic fiber blanket 10 having a thickness of about 4 to 8 mm is used. The fireproof sheet 4 corresponds to the one in which the ceramic fiber blanket 10 is used instead of the flame-retardant plastic foam sheet 6 in Example 2, and the other configurations are the same as in Example 2.

Next, the result of conducting the same fire resistance test as in Example 1 by winding this fireproof sheet on a cable will be described. The fireproof sheet used in the test was obtained by laminating a fireproof net 1, an aluminum foil 5 with a thickness of 50 μm, a ceramic fiber blanket 10 with a thickness of 6 mm, and an aluminum foil 7 with a thickness of 20 μm in this order, and Are joined together. From the test results, it was confirmed that there is a fire spread prevention effect, and the maximum temperature of the cable reached 189 ° C, but there was no decrease in insulation resistance, and the appearance of the cable sheath after the test was such that traces of melting were visible. , Was almost good.

[Embodiment 5] FIG. 5 shows an embodiment of the present invention. The fireproof sheet 4 includes a fireproof net 1, an aluminum foil 5, a ceramic fiber blanket 10,
A composite sheet 9 obtained by laminating a flame-retardant paper 11 for reinforcement on an aluminum foil 7 is laminated in this order, and each layer is joined with an adhesive. Ceramic fiber blanket 1
The weak bonding force between 0 and the aluminum foils 5 and 7 is the same as in the fourth embodiment.

Next, the result of conducting the same fire resistance test as in Example 1 by winding this fireproof sheet on a cable will be described. In the fireproof sheet used in the test, instead of the lowermost aluminum foil of the fireproof sheet of Example 4, a composite sheet 9 in which an aluminum foil 7 and a flame retardant paper 11 were laminated was laminated with the flame retardant paper 11 on the outside. Other than that, the configuration is the same as that of the fourth embodiment.
From the test results, it was confirmed that there was an effect of preventing the spread of fire, the maximum temperature of the cable was 97 ° C., there was no reduction in insulation resistance, and the appearance of the cable sheath after the test was good.

According to this result, the maximum temperature of the cable is significantly lower than that in the case of Example 4, and it is understood that the flame-retardant paper 11 laminated on the aluminum foil 7 greatly contributes to the improvement of the heat insulating property. . Further, when the composite sheet 9 in which the flame-retardant paper 11 is laminated on the aluminum foil 7 is used as the lowermost layer, the aluminum foil 7 on the side in contact with the cable is reinforced by the flame-retardant paper 11, so that it may be torn when wound around the cable. There is also an advantage that it is easy to handle.

In the embodiment of FIG. 5, the composite sheet 9 is laminated on the ceramic fiber blanket 10 with the aluminum foil 7 inside, but the composite sheet 9 may be laminated with the aluminum foil 7 outside. Further, as the reinforcing sheet for the aluminum foil 7, it is possible to use glass cloth or the like instead of the flame-retardant paper 11.

In each of the above examples, a flame-retardant plastic foam sheet having no cuts formed on one side or both sides was used, but similar results can be obtained even if a large number of parallel cuts are formed on one side or both sides. To be

[0031]

As described above, if the fireproof sheet of the present invention is wrapped around a cable, it is possible to prevent the spread of the cable when a fire occurs and to function as a cable for a certain time (at least 20 minutes or more). Can be maintained. Therefore, it has a remarkable effect in preventing the spread of fire, securing information transmission function in case of fire, and securing lighting. Since the fireproof sheet of the present invention is relatively thin,
It is easy to handle when it is wrapped around the cable.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of a fireproof sheet according to the invention of claim 1.

FIG. 2 is a sectional view showing an embodiment of a fireproof sheet according to the invention of claim 2.

FIG. 3 is a sectional view showing an embodiment of a fireproof sheet according to the invention of claim 3.

FIG. 4 is a sectional view showing an embodiment of a fireproof sheet according to the invention of claim 4;

FIG. 5 is a sectional view showing an embodiment of a fireproof sheet according to the invention of claim 5;

FIG. 6 is a perspective view of a conventional fireproof net.

[Explanation of symbols]

 1: Fireproof net 2: Net body 3: Thermal foaming paint 4: Fireproof sheet 5: Aluminum foil 6: Flame-retardant plastic foam sheet 7: Aluminum foil 8: Glass cloth 9: Composite sheet 10: Ceramic fiber blanket 11: Difficulty Burning paper

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junichiro Wake, 5-18 Higashihachiman, Hiratsuka City, Kanagawa Prefecture Furukawa Techno Material Co., Ltd. (72) Inventor Keiwa Kobayashi 5-23, Nishigotanda, Shinagawa-ku, Tokyo No. 8 In stock company Shinsei Denshi

Claims (5)

[Claims] 1. A fireproof net formed by coating a fire resistant net body with a heat-foaming paint that foams by heat in a fire to form a fire resistant heat insulating layer, a metal foil, and a flame retardant plastic foam sheet. A fireproof sheet for flammable cables, characterized by being laminated in this order. 2. A fireproof net formed by applying a heat-foaming paint that foams by heat in a fire to form a fireproof heat insulating layer on a fireproof net body, a metal foil, and a flame-retardant plastic foam sheet. A fireproof sheet for a flammable cable, characterized in that a metal foil and a metal foil are laminated in this order. 3. A fireproof net formed by applying a heat-foaming paint that foams by heat in a fire to form a fireproof heat insulating layer on a fireproof net body, a metal foil, and a flame-retardant plastic foam sheet. A fireproof sheet for a flammable cable, comprising a metal foil and a composite sheet obtained by laminating a reinforcing sheet in this order. 4. A fireproof net formed by applying a heat-foaming paint that foams by heat in a fire to form a fireproof heat insulating layer on a fireproof net body, a metal foil, a ceramic fiber blanket, and a metal foil. A fireproof sheet for flammable cables, characterized in that and are laminated in this order. 5. A fireproof net formed by applying a heat-foaming paint that foams by heat in a fire to form a fireproof heat insulating layer on a fireproof net body, a metal foil, a ceramic fiber blanket, and a metal foil. A fireproof sheet for a flammable cable, characterized in that a reinforcing sheet and a composite sheet are laminated in this order.