JP6734220B2 - Fireproof protection tube, installation method of fireproof protection tube, fireproof protection structure - Google Patents

Description

The present invention mainly relates to fireproof protection tubes for power cables and communication cables.

A power cable and a communication cable laid along a railroad track or the like are housed in a flexible protective tube made of resin, for example. In recent years, there have been cases where a cable is burned down due to abandoned cigarettes, an ignition caused by some kind of mischief, or the like, and a serious event such as operation stop of a train is caused. Therefore, it is necessary to protect the cable with a flame-retardant protection tube or the like.

Various flame-retardant protection tubes have been proposed (for example, Patent Documents 1 to 5).

JP, 2000-88147, A JP, 2001-31184, A JP 2004-208346 A JP, 2006-174570, A JP, 2007-68268, A

However, when laying a new cable, a flame-retardant protection tube may be used instead of the normal protection tube, but when applying to an existing cable, disconnect the cable once, It is necessary to re-install it in a new protection tube and reconnect the cable. In particular, in the case of a signal cable, once the cable is removed, a retest is required, which requires working time. However, in the case of a protective tube having a crack, the fire resistance of the crack may deteriorate.

FIG. 4 is a schematic diagram of the cable laying structure 100 on the side of the track. As described above, the power cable and the like are inserted into the cable protection tube 101. The power cable or the like is connected to the switchboard 103 or the like near the station, for example. Therefore, the power cable or the like stands up almost vertically.

However, regarding the fire resistance of the cable, a high degree of flame retardancy is required in the rising portion (vertical portion) where the conditions are the worst. Further, at the time of combustion due to a fire, even if the protective tube itself does not burn, if the temperature inside the protective tube rises, there is concern that the coating of the internal cable may melt and the electric wire function may be lost.

The present invention has been made in view of such a problem, and an object thereof is to provide a fireproof protective tube or the like having excellent workability and sufficient fire resistance.

In order to achieve the above-mentioned object, the first invention comprises a flexible tube made of resin and a refractory sheet arranged all around the outer circumference of the flexible tube, wherein the flexible tube is at least Part of the split portion of the flexible tube has a split portion continuous in the longitudinal direction, a hinge portion is formed at a portion other than the split portion, and the split portion of the flexible tube can be opened and closed by the hinge portion. Is protruding from the edge of at least one of the split portions, the inner surface of the protruding portion of the fire-resistant sheet, an adhesive protected by release paper is disposed, the fire-resistant sheet foams and expands during combustion. The flexible tube is a corrugated tube, and the same concavo-convex as the corrugated tube is formed in the hinge section when the hinge section is closed. It is a characteristic fire protection tube.
The hinge portion may be formed by a notch provided in a part of the flexible tube, and may be formed by cutting a part of a protrusion protruding to an inner surface of the corrugated tube and leaving a part thereof.
The hinge part may be formed by connecting the flexible tubes divided into two parts by the refractory sheet, and the flexible tubes divided into two parts may be arranged in parallel with each other.

The refractory sheet may be thermocompression bonded to the outer circumference of the flexible tube.

An adhesive sheet may be attached to the inner surface of the hinge portion in the longitudinal direction.

The refractory sheet preferably has an oxygen index of 35 or more and a thickness of 1 mm to 4 mm.

According to the first aspect of the present invention, since the flexible tube has the split portion, it can be easily attached to the outer circumference of the existing cable or protection tube. At this time, since the hinge part is provided in part, it is easy to open the split part. Further, since the fireproof sheet protrudes from one end of the flexible tube, the split portion can be covered with the fireproof sheet. Therefore, sufficient fire resistance can be obtained even for the split portion.

Further, since the fireproof sheet is simply attached by the adhesive, the work of covering the flexible tube with the fireproof sheet and fixing the flexible tube is easy. At this time, since the pressure sensitive adhesive is protected by the release paper, it is easy to handle.

In addition, by fixing the refractory sheet to the flexible tube by thermocompression bonding, manufacturing is easy.

Further, if the hinge portion is a notch of a part of the flexible tube, the split portion and the hinge portion can be simultaneously processed from the state of the complete tubular body.

In addition, since the hinge portion is formed by connecting one ends of the flexible tubes divided into two, processing such as cutting is unnecessary.

At this time, since the adhesive sheet is attached to the inner surface of the hinge portion, the flexible tube divided into two parts is less likely to be displaced during processing.

If the oxygen index of the refractory sheet is not less than the predetermined value, sufficient fire resistance can be ensured. Further, when the thickness of the fireproof sheet is a predetermined value or more, it is possible to suppress heat transfer to the inside of the protective tube due to the heat insulating effect. Further, if the thickness of the fireproof sheet is not more than a predetermined value, sufficient flexibility can be secured.

In addition, since the refractory sheet foams and expands during combustion, a higher heat insulating effect can be obtained. In addition, heat resistance can be maintained by solidifying the fire resistant sheet during combustion.

A second aspect of the present invention uses the fire-resistant protective tube according to the first aspect of the present invention to open the split portion and attach the fire-resistant protective tube to the outer circumference of an existing cable or a protective tube through which the cable is inserted, and attach the split portion. In the closed state, cover the split portion with the protruding portion of the refractory sheet, peel off the release paper, and attach the protruding portion of the fire resistant sheet to the outer surface of the fire resistant sheet on the inner peripheral side with the adhesive. It is a method of installing a fireproof protection tube characterized by.

According to the second invention, the protection tube can be easily attached to the outer circumference of the existing cable or protection tube.

In a third aspect of the present invention, a cable or a protective tube having the cable inserted therein is arranged in the fireproof protective tube, and the fireproof protective tube is arranged around a flexible tube made of resin and the entire outer circumference of the flexible tube. A refractory sheet according to the present invention, wherein the flexible tube has a split portion continuous in at least a part in the longitudinal direction, a hinge portion is formed at a portion other than the split portion, It is possible to open and close the split portion of the flexible tube, the fire-resistant sheet is protruding from the edge of at least one of the split portion, an adhesive is disposed on the inner surface of the protruding portion of the fire-resistant sheet, the fire-resistant The sheet is made of a material that foams and expands during combustion to solidify into a glass shape, the flexible tube is a corrugated tube, and the corrugated tube is provided in the hinge section with the hinge section closed. The same unevenness is formed, the split portion is covered with the protruding portion of the refractory sheet in a closed state, and the refractory sheet is attached to the outer surface of the inner refractory sheet with the adhesive. It is a fire protection structure characterized by.

According to the third invention, it is possible to obtain a fireproof protective structure having sufficient fireproof performance.

According to the present invention, it is possible to provide a fireproof protective tube having excellent workability and sufficient fire resistance.

(A) is sectional drawing which shows the fireproof protective tube 1, (b) is the A section enlarged view of (a). (A) is a figure which shows the state which closed the fireproof protective pipe 1, (b) is a figure which shows the fireproof protective structure 20. (A) is a figure which shows the fireproof protective tube 1a, (b) is a figure which shows the fireproof protective tube 1b. The figure which shows the cable laying structure 100.

Hereinafter, embodiments of the present invention will be described in detail. FIG. 1A is a sectional view showing a fireproof protection tube 1 according to the present invention. The fireproof protection tube 1 is composed of a flexible tube 3 and a fireproof sheet 5.

The flexible tube 3 is a corrugated tube made of resin. At least a part of the flexible tube 3 has a split portion 7 continuous in the longitudinal direction. In addition, a hinge portion 9 is formed in a portion other than the split portion 7. The split portion 7 of the flexible tube 3 can be opened and closed by the hinge portion 9.

The hinge portion 9 is formed by connecting the flexible tubes 3 (a pair of half-split flexible tubes) divided into two. In the illustrated example, the hinge portions 9 are connected by the fireproof sheet 5 described later. An adhesive sheet 17 is attached to the inner surface of the hinge portion 9 in the longitudinal direction.

A refractory sheet 5 is arranged on the outer peripheral surface of the flexible tube 3 over the entire circumference. That is, the fireproof sheet 5 is arranged from the split portion 7 at one end of the flexible tube 3 to the other split portion 7 via the outer surface of the hinge portion 9. Further, the fire resistant sheet 5 has a protruding portion 11 that protrudes from the edge of at least one of the split portions 7. That is, the width of the refractory sheet 5 is sufficiently longer than the outer peripheral length of the flexible tube 3.

The fireproof sheet 5 is, for example, thermocompression bonded to the outer circumference of the flexible tube 3. By sticking the refractory sheet 5 by thermocompression bonding, it is not necessary to use an adhesive or the like. In addition, there is no fear that the adhesive will peel off due to deterioration over time.

FIG. 1B is an enlarged view of part A of FIG. An adhesive 13 protected by a release paper 15 is disposed on the inner surface of the protruding portion 11 near the tip of the fireproof sheet 5. The adhesive 13 may be arranged on the entire length of the protruding portion 11.

Next, a method for installing the fireproof protection tube 1 will be described. First, as shown in FIG. 2A, the split portion 7 is opened and the fireproof protection pipe 1 is attached to the outer circumference of the existing cable 19 or the protective tube 21 in which the cable 19 is inserted, and the split portion 7 is closed. .. Further, with the split portion 7 closed, the split portion 7 is covered with the protruding portion 11 of the fireproof sheet 5.

Further, as shown in FIG. 2B, the release paper 15 is peeled off, and the protruding portion 11 of the fireproof sheet 5 is adhered to the inner side of the fireproof sheet 5 (the fireproof sheet attached to the flexible tube 3 by the adhesive 13). Attach to the outer surface of sheet 5). By the above, the fireproof protection structure 20 is constructed.

The length of the protruding portion 11 is preferably 50 mm or more, for example. If the length of the protruding portion 11 is 50 mm or more, it is possible to prevent the overlapping portion from opening due to the other end being turned over in the event of a fire.

In order to ensure sufficient fire resistance, the oxygen index of the fire resistant sheet 5 is preferably 35 or more, more preferably 40 or more, as measured by JIS K6269. By setting the oxygen index to a predetermined value or more, when the fire source disappears, it can be immediately digested and fire spread can be suppressed.

Further, the thickness of the fireproof sheet 5 is preferably 1 mm or more. If the thickness of the fireproof sheet 5 is less than 1 mm, it may be difficult to secure sufficient fireproof performance and heat insulation performance. On the other hand, the thickness of the fireproof sheet 5 is preferably 4 mm or less. If the thickness of the fireproof sheet 5 exceeds 4 mm, the flexibility of the fireproof protective tube 1 deteriorates, and handling becomes difficult.

Further, it is desirable that the refractory sheet 5 foams and expands during combustion. By doing so, sufficient heat insulation is ensured during combustion, and an increase in internal temperature can be suppressed. Further, if the refractory sheet 5 is solidified when expanded, it is possible to prevent the expanded refractory sheet from collapsing and collapsing, and to maintain heat insulation. As a material of such a fireproof sheet 5, for example, Proteco Tape No. 2 (trade name) manufactured by Furukawa Techno Material Co., Ltd. can be applied.

As described above, according to the present embodiment, since the fireproof protection tube 1 has the hinge portion 9, the split portion 7 can be easily opened, and the split portion 7 can be easily attached to the outer circumference of the existing cable 19 or the like. You can In addition, since the fireproof sheet 5 covers the entire circumference of the flexible tube 3 including the split portion 7, sufficient fireproof performance can be ensured.

Further, since the pressure sensitive adhesive 13 with the release paper 15 is arranged on the inner surface of the protruding portion 11, the work can be easily performed on site and the handling is easy.

Further, since the flexible tube 3 divided into two is connected by the fireproof sheet 5 to form the hinge portion 9, the flexible tube 3 can be manufactured by a pair of half-split tubes having the same shape. Further, since the adhesive sheet 17 is attached to the inner surface of the connecting portion (hinge portion 9) of the two half-split pipes, the half-split pipes are unlikely to be displaced when the fireproof sheet 5 is pressure-bonded.

Further, since the refractory sheet 5 has the properties of foaming thermal expansion and solidification at the time of combustion, sufficient fire resistance performance and heat insulation effect at the time of combustion can be obtained. Therefore, even if a fire occurs, it is possible to prevent the internal cable from becoming unusable, and it is possible to deal with it only by replacing the external fire protection tube.

Next, another embodiment will be described. FIG. 3A is a diagram showing the fireproof protection pipe 1a. In addition, in the following description, components having the same functions as those of the fire protection tube 1 are designated by the same reference numerals as those in FIG.

The fire-resistant protective tube 1a has substantially the same structure as the fire-resistant protective tube 1, but the joining method between the fire-resistant sheet 5 and the flexible tube 3 is different. In the fireproof protective tube 1 a, the adhesive 13 is provided on the entire inner surface of the fireproof sheet 5. The refractory sheet 5 is attached to the entire circumference of the flexible tube 3 with an adhesive 13.

In this case, since the adhesive 13 is provided over the entire length of the protruding portion 11, the release paper 15 is arranged so as to cover the entire adhesive 13 in the protruding portion 11. Therefore, the protruding portion 11 does not stick to other parts during handling.

The fire protection tube 1a can also provide the same effect as the fire protection tube 1. As described above, as a method for attaching the fireproof sheet 5, if the fireproof protective tube 1 is easy to manufacture and the state where the fireproof protective tube 1 is attached to the outer peripheral surface of the flexible tube 3 can be maintained for a long period of time, the method is It is not particularly limited.

Moreover, FIG.3(b) is a figure which shows the fireproof protection pipe 1b. The fireproof protection tube 1b has substantially the same configuration as the fireproof protection tube 1, but the hinge portion 9 has a different form. In the fireproof protection tube 1b, not one end of the flexible tube 3 divided into two is connected to form the hinge portion 9, but a cut is formed in a part of the flexible tube 3 to form the hinge portion 9. It

In this case, when the tubular flexible tube is cut with the cutter to form the split portion 7, the hinge portion 9 is formed by making a cut in a part of the inner surface of the facing portion of the split portion 7. You can For example, as described above, since the flexible tube 3 is a corrugated tube, a part of the protrusion protruding to the inner surface of the flexible tube 3 is cut, and it is not completely cut so as to leave a part. Thus, the hinge portion 9 can be easily formed.

The fireproof protection tube 1b can also achieve the same effect as the fireproof protection tube 1. Further, even if the flexible tube 3 is not completely divided into two parts, a part having lower rigidity than the other parts may be formed as the hinge part 9.

Several types of samples were prepared and the following were evaluated.
Oxygen index: measured according to JIS K6269, and an oxygen index of 35 or higher was passed.
Flexibility: A pipe that can be bent by 1/2 along a pipe having a diameter of 1 m by human power and at which time no abnormality such as cracking occurs was accepted.
Fire resistance: In the vertical combustion test of IEEE 383, after burning for 20 minutes and removing the fire source, the conduit did not continue burning and the damage distance was 1 m or less.
Electric wire function: In the fire resistance test, there is no melting of the internal electric wire coating portion, and the electric wire that can be continuously used (reusable) even after combustion is passed. As a guide, those having an internal temperature of 100° C. or less were regarded as acceptable.

(No. 1)
A refractory rubber sheet having a thickness of 1.4 mm and a width of 900 mm was attached to a hinged tube having a split portion in a part of a plastic corrugated tube having a nominal diameter of 200 mm (outer diameter 253 mm, inner diameter 200 mm). The plastic corrugated tube used was Flex (trade name) manufactured by Furukawa Electric Co., Ltd., and the fire-resistant rubber sheet was Proteco Tape No. 2 (trade name) manufactured by Furukawa Techno Materials Co., Ltd. The oxygen index of the refractory rubber sheet is 40.

A butyl-based pressure-sensitive adhesive having a thickness of 1 mm was attached to both ends 30 mm in the width direction of the fire resistant rubber sheet. As the adhesive, F-CO TAPE No. 1 (trade name) manufactured by Furukawa Electric Power Systems Co., Ltd. was used. One end of the fire-resistant rubber sheet was attached to a flexible tube, and the fire-resistant rubber sheet was arranged about one round. Further, a protruding portion of about 100 mm was provided as a stacking margin to manufacture a fire-resistant protective tube. A release paper is attached to the adhesive at the end 30 mm of the protruding portion, and the adhesive is removed and adhered at the time of construction.

In addition, as a fire resistance evaluation, an IEEE383 vertical combustion test was performed. At this time, a plurality of φ20 mm PVC-coated electric wires were inserted into the fire protection tube so that the occupied volume was about 60%.

(No. 2)
A fire-resistant rubber sheet having a thickness of 2.8 mm and a width of 400 mm was attached to a hinged tube having a split portion in a part of a plastic corrugated tube having a nominal diameter φ80 mm (outer diameter 102 mm, inner diameter 80 mm). Further, the length of the protruding portion was set to 80 mm, and a fireproof protection tube was produced. The materials such as the plastic corrugated pipe, the fire-resistant rubber sheet, and the adhesive are No. Same as 1. The adhesive placement is also No. The same as 1. In addition, No. 1 was used as the evaluation of fire resistance. The same test as 1 was performed.

(No. 3)
Half-divided (two-divided) plastic corrugated pipes having a nominal diameter of 80 mm were abutted and arranged in parallel, and an adhesive tape (width 40 mm) was attached in the length direction to cover the two abutted end faces. Furthermore, the No. A 1.4 mm-thick fire-resistant rubber sheet (protruding portion 80 mm) to which the same adhesive as in 1 was attached was closely arranged. This was compressed and closely contacted with a metal mold (length: 500 mm) having an upper and lower substantially cross-sectional shape, which was sequentially fed in the length direction and compressed to be integrated into a fireproof protection tube. The materials such as the plastic corrugated pipe, the fire-resistant rubber sheet, and the adhesive are No. Same as 1. The adhesive placement is also No. The same as 1. In addition, No. 1 was used as the evaluation of fire resistance. The same test as 1 was performed.

(No. 4)
No. A fire-resistant protective tube similar to that of No. 3 was produced, and a plastic corrugated tube (same material) with a nominal diameter of φ50 mm (outer diameter of 65 mm, inner diameter of 50 mm) was further placed inside, and a volume of φ10 mm PVC-covered electric wire was occupied in it. Multiple pieces were inserted so that the percentage became %.

(No. 5)
The corrugated pipes made of halves (two divisions) with a nominal diameter of φ80mm are placed in parallel with each other, and the two end faces that are abutted are covered and adhesive tape (width 40mm) is attached in the length direction. A fireproof rubber sheet with an adhesive was attached over the outer circumference. The fire-retardant rubber sheet with adhesive is a 1.4 mm thick Proteco Tape No. 2 (product side) made by Furukawa Techno Material Co., Ltd., with a 1 mm thick flame-retardant F-CO Tape No. 2 made by Furukawa Electric Power Systems Co., Ltd. A butyl rubber having an oxygen index of 26) attached was used. The length of the protruding portion was set to 80 mm and used as a fireproof protection tube. No. 1 was used as the evaluation of fire resistance. The same test as 1 was performed.

(No. 6)
No. No fire-resistant rubber sheet was attached to No. 1 and only a corrugated pipe made of plastic was used. As the plastic corrugated tube, flame-retardant Eflex (trade name) manufactured by Furukawa Electric Co., Ltd. was used. No. 1 was used as the evaluation of fire resistance. The same test as 1 was performed.

(No. 7)
For a pipe with a hinge having a split portion in a part of a plastic corrugated pipe with a nominal diameter of 80 mm, No. The same electric wire as that in No. 2 was inserted, and the flame-retardant adhesive tape was wound around the wrap in a half way. The flame-retardant pressure-sensitive adhesive tape was Furukawa Electric Power Systems Co., Ltd. flame-retardant FCO tape No. 2 (trade name). The oxygen index of the flame-retardant adhesive tape was 26. The evaluation of fire resistance is No. The same test as 1 was performed.

(No. 8)
No. except that the thickness of the fire resistant rubber sheet was 0.7 mm. A fireproof protective tube was prepared and tested in the same manner as in 3. The evaluation of fire resistance is No. The same test as 1 was performed.

(No. 9)
No. except that the thickness of the fire resistant rubber sheet was 5 mm. A fireproof protective tube was prepared and tested in the same manner as in 3. The evaluation of fire resistance is No. The same test as 1 was performed.

(No. 10)
Compared with the hinged half of a plastic corrugated pipe with a nominal diameter of 80 mm, No. An electric wire similar to that of No. 2 was inserted, and an aluminum foil pressure-sensitive adhesive tape having a thickness of 0.1 mm and a width of 50 mm was wound back and forth once with a 1/2 wrap, and a test was conducted. The evaluation of fire resistance is No. The same test as 1 was performed.

(No. 11)
No. 1 except that a flame-retardant rubber sheet having a thickness of 1.5 mm was used instead of the fire-resistant rubber sheet. A fireproof protective tube was prepared and tested in the same manner as in 3. The flame-retardant rubber sheet is a flame-retardant rubber sheet containing 20% by mass of ethylene propylene rubber, 8% by mass of butyl rubber, 10% by mass of process oil, 57% by mass of aluminum hydroxide and 5% by mass of antimony trioxide, and has an oxygen index of 32. Met. The evaluation of fire resistance is No. The same test as 1 was performed.

Table 1 shows the evaluation results. No. In No. 1, as a confirmation of flexibility, the metal tube having a diameter of 1 m could be bent by 1/2 turn, and there was no problem such as cracks. Regarding the fire resistance, the gas burner flame at 815°C burned for 20 minutes, but immediately after the burner was extinguished, the protective tube burned out and the burning distance was 650 mm. After the test, the fire-resistant rubber sheet foamed to a thickness of 3.5 mm and solidified into a glass shape and did not collapse. Moreover, the surface temperature of the coating of the PVC electric wire inside was 70° C., the coating was not melted, and the electric wire function of the cable was not a problem.

No. For No. 2, as a flexibility check, it was possible to bend it along the metal tube having a diameter of 1 m by 1/2 turn, and there was no problem such as cracks. Regarding the fire resistance, the gas burner flame at 815° C. was burned for 20 minutes, but immediately after the burner was extinguished, the protective tube was not burned and the burning distance was 690 mm. The fire-resistant rubber sheet after the test was foamed to have a thickness of 6.5 mm, solidified into a glass shape, and did not collapse. Further, the surface temperature of the coating of the PVC electric wire inside was 72° C., the coating was not melted, and the electric wire function of the cable was not a problem.

No. No. 3 could be bent along the metal pipe having a diameter of 1 m for confirmation of flexibility, and there was no problem such as cracks. Regarding the fire resistance, the protective tube did not burn immediately after the burner was extinguished, and the burning distance was 680 mm. The fire-resistant rubber sheet after the test was foamed to have a thickness of 3.5 mm, solidified in a glass shape, and did not collapse. Further, the surface temperature of the coating of the PVC electric wire inside was 71° C., the coating did not melt, and there was no problem in energizing the cable.

No. No. 4 could be bent along the metal tube having a diameter of 1 m for ½ round as a confirmation of flexibility, and there was no problem such as cracks. Regarding the fire resistance, the protective tube did not burn immediately after the burner was extinguished, and the burning distance was 670 mm. The fire-resistant rubber sheet after the test was foamed to have a thickness of 3.5 mm, solidified in a glass shape, and did not collapse. Further, the internal φ50 plastic corrugated pipe was not burned, the surface temperature of the PVC electric wire coating was 68° C., the coating was not melted, and the electric wire function of the cable was not a problem.

No. No. 5 could be bent along the metal tube having a diameter of 1 m for ½ round as a confirmation of flexibility, and there was no problem such as cracks. Regarding the fire resistance, the protective tube did not burn immediately after the burner was extinguished, and the burning distance was 680 mm. After the test, the pressure-sensitive adhesive-resistant fire-resistant rubber sheet foamed to a thickness of 4.5 mm, solidified into a glass shape, and did not collapse. Further, the surface temperature of the coating of the PVC electric wire inside was 70° C., the coating was not melted, and the electric wire function of the cable was not a problem.

No. 6 also had no problem in flexibility. However, in the fire resistance test, combustion continued for 5 minutes even after the burner was extinguished, the combustion distance was 1500 mm, the internal temperature was 280° C., and the PVC wire coating was molten. As a result, the electrical conductivity of the electric wire was unacceptable.

No. No. 7 had no problem in flexibility. However, in the fire resistance test, combustion continued after the burner was extinguished, and the flame-retardant adhesive tape part collapsed and burned for the entire length. The internal temperature was 360° C., the coating of the PVC electric wire was molten, and the electric wire function was unacceptable.

No. No. 8 had no problem in flexibility. However, in the fire resistance test, combustion continued for 2 minutes even after the burner was extinguished, the combustion distance was 1100 mm, and the fire resistant rubber sheet foamed to a thickness of 2 mm, but the internal temperature was 150° C. The coating was melted and the electric wire function failed.

No. In the flexibility test, No. 9 was hard and could not be bent as desired, and was unacceptable. In the fire resistance test, combustion of the protective tube disappeared immediately after extinguishing the burner, and the combustion distance was 650 mm. The fire-resistant rubber sheet after the test was foamed to have a thickness of 10 mm. Moreover, the surface temperature of the coating of the PVC electric wire inside was 65° C., the coating did not melt, and the electric wire function was not a problem.

No. In the flexibility test, No. 10 was hard and could not be bent as desired. In the fire resistance test, combustion did not continue after the burner was extinguished, but the internal temperature reached 320°C, the PVC wire coating melted, and the wire function failed.

No. No. 11 had no problem in flexibility. However, in the fire resistance test, combustion continued for 5 minutes even after the burner was extinguished, the combustion distance was 1300 mm, and the flame-retardant rubber sheet foamed to a thickness of 2.5 mm, but partly remained without solidification. It was collapsed, the internal temperature was 230° C., the coating of the PVC electric wire was melted, and the electric wire function was unacceptable.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical scope of the present invention is not affected by the above-described embodiments. It is obvious to those skilled in the art that various alterations or modifications can be conceived within the scope of the technical idea described in the claims, and those are naturally within the technical scope of the present invention. It is understood that it belongs.

1, 1a, 1b....Fireproof protective tube 3...Flexible tube 5...Fireproof sheet 7...Split portion 9...Hinge portion 11...Overhanging portion 13...Adhesive 15... ......Release paper 17 ......Adhesive sheet 19 ......Cable 20 ......Fireproof protection structure 21 ......Protection tube 100 ......Cable laying structure 101 ......Cable protection tube 103 ......Switchboard

Claims (8)

A flexible tube made of resin,
A refractory sheet arranged all around the outer circumference of the flexible tube,
Equipped with,
The flexible tube has a split portion continuous in at least a part in the longitudinal direction,
A hinge portion is formed in a portion other than the split portion, and the split portion of the flexible tube can be opened and closed by the hinge portion,
The refractory sheet is protruding from the edge of at least one of the split portions,
On the inner surface of the protruding portion of the fireproof sheet, an adhesive protected by release paper is arranged,
The refractory sheet is made of a material that foams and expands when burned, and solidifies into a glass.
The flexible tube is a corrugated tube,
The fireproof protection tube, wherein the hinge section has the same unevenness as the corrugated tube in the closed state. The hinge portion is formed by a notch provided in a part of the flexible tube, and is formed by cutting a part of a protrusion protruding to an inner surface of the corrugated tube and leaving a part thereof. The fireproof protective tube according to claim 1. The hinge portion is formed by connecting the flexible tubes divided into two by the fire resistant sheet,
The fireproof protection tube according to claim 1, wherein the flexible tubes divided into two are butted and arranged in parallel. The fireproof protective tube according to any one of claims 1 to 3, wherein the fireproof sheet is thermocompression-bonded to the outer periphery of the flexible tube. The fireproof protective tube according to claim 3 or 4, wherein an adhesive sheet is attached to the inner surface side of the hinge portion in the longitudinal direction. The fireproof protective tube according to any one of claims 1 to 5, wherein the fireproof sheet has an oxygen index of 35 or more and a thickness of 1 mm to 4 mm. Using the fireproof protection tube according to any one of claims 1 to 6 ,
On the outer circumference of the existing cable or the protective tube in which the cable is inserted, open the split portion and attach the fireproof protective tube,
In a state where the split portion is closed, the split portion is covered with the protruding portion of the refractory sheet, the release paper is peeled off, and the protruding portion of the fire resistant sheet is covered with the adhesive to the outer surface of the fire resistant sheet on the inner peripheral side. A method of installing a fireproof protective tube, characterized by being attached to the. In the fireproof protection tube, a cable or a protection tube with a cable inserted is placed,
The fire protection tube is
A flexible tube made of resin,
A refractory sheet arranged all around the outer circumference of the flexible tube,
Equipped with,
The flexible tube has a split portion continuous in at least a part in the longitudinal direction,
A hinge portion is formed in a portion other than the split portion, and the split portion of the flexible tube can be opened and closed by the hinge portion,
The refractory sheet is protruding from the edge of at least one of the split portions,
On the inner surface of the protruding portion of the fireproof sheet, an adhesive is arranged,
The refractory sheet is made of a material that foams and expands when burned, and solidifies into a glass.
The flexible tube is a corrugated tube,
With the hinge portion closed, the same protrusions and depressions as the corrugated tube are formed on the hinge portion,
The fireproof protection structure, wherein the split portion is covered with a protruding portion of the fireproof sheet in a closed state, and the fireproof sheet is attached to an outer surface of the fireproof sheet on an inner peripheral side with the adhesive.

Images