JP2000032638A - Cable protective pipe, cable protective pipe joint and cable conduit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize the damages of a cable protective pipe and a cable protective pipe joint, even if a fire occurs under a bridge and use them continuously after a fire. SOLUTION: A protective pipe is made of fiber-reinforced synthetic resin, whose impregnating resin is brominated unsaturated polyester resin. Inorganic flame-retardant agent is added to the impregnating resin. A flame-retardant polyester nonwoven fabric is used as the fiber material, of which the surface layer 15 of the protective pipe is made. Or the protective pipe is made of a fiber-reinforced synthetic resin whose impregnating resin contains brominated unsaturated polyester resin as its main component. The protective pipe is used as a cable protective pipe installed along a bridge.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable protection pipe, a cable protection pipe joint, and a cable pipe, and more particularly, to a cable protection pipe which is useful for construction of a bridge-attached cable pipe.

[0002]

2. Description of the Related Art A cable protection tube made of fiber-reinforced synthetic resin is lightweight, has excellent workability, is non-corrosive, is not subject to electric corrosion, is easy to maintain, is non-magnetic, and is iron. There is an advantage that there is no loss or the like, and in particular, when used as a cable line for connecting a bridge, there is also an advantage that the load burden on the bridge can be reduced. Conventionally, an unsaturated polyester (usually maleic anhydride / ethylene glycol-based unsaturated polyester) is used as an impregnating resin for a cable protective tube made of fiber-reinforced synthetic resin.
And a continuous drawing method using a glass fiber as the reinforcing fiber and a polyester non-woven fabric as the fiber material of the surface layer.

[0003]

In a cable line along a bridge, it is necessary to take measures against a misfire caused by a fire or the like on a riverbed under the bridge. In the above-mentioned glass fiber reinforced unsaturated polyester tube, even if the glass fiber is nonflammable, there is a problem that the fire spreads easily due to the flammability of the unsaturated polyester. Further, it is conceivable to use a flame-retardant resin as the impregnating resin to make the entire length of the cable protection tube flame-retardant, but there is a problem in cost.

[0004] The inventors of the present invention have intensively studied the fire resistance of a fiber reinforced synthetic resin tube material by simulating a fire under a bridge. Under the arrangement, the spread of fire can be kept light,
He knew that sufficient measures could be taken without imparting noncombustibility or a high degree of self-extinguishing properties to the entire length of the pipeline. -Constructing a cable protection tube portion made of a fiber-reinforced resin cable using a phenol resin or a modified phenol resin as the impregnating resin "(Japanese Patent Application No. 8-313093). .

[0005] However, according to the results of the subsequent studies, it has been found that simply replacing the unsaturated polyester with a phenolic resin for the glass fiber reinforced unsaturated polyester cable protective tube, that is, impregnating the phenolic resin into the impregnated resin. Even if glass fiber is used as the reinforcing fiber and polyester non-woven fabric is used as the fiber material of the surface layer, the state of infiltration of the resin in the surface layer becomes uneven, and the fire spreads lightly as described above. Even if it could be suppressed, it was found that the appearance spread and the strength were significantly reduced in the fire spread portion, which hindered the subsequent continuous use.

[0006] The object of the present invention is based on these findings,
An object of the present invention is to make it possible to construct a bridge-attached cable conduit that can continue to be used even if a fire occurs under a bridge, while minimizing damage.

[0007]

A cable protection tube and a cable protection tube joint according to the present invention are made of a fiber-reinforced synthetic resin using a brominated unsaturated polyester resin as an impregnating resin. It is preferable to add an inorganic flame retardant to the impregnated resin.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a case according to the present invention.
It is drawing which shows an example of a bull protection tube. In FIG. 1, 1
1 is the FRP layer of the longitudinal fiber, 12 is the FRP layer of the horizontal fiber,
Reference numeral 13 denotes an FRP layer of longitudinal fibers, 14 denotes an FRP layer of mat or cloth fibers, and 15 denotes a resin-impregnated surface layer for providing a smooth surface.
As the impregnating resin for the surface layer 15, a brominated unsaturated polyester resin to which inorganic flame retardant is added is used.

The combustion mechanism of the resin is such that a peroxide is generated by thermal decomposition of a polymer, and this peroxide is converted into an active radical by the action of heat and oxygen, and heat is generated by a chain reaction between the active radical and oxygen. The thermal decomposition of the polymer is repeated, and at the same time, decomposition products such as monomers and carbon are formed on the resin surface. In the brominated unsaturated polyester resin, since the binding energy of bromine is lower than that of other halogens, bromine is easily released from the resin polymer to suppress the generation of the radicals and reduce the heat generation. To suppress combustion. The brominated unsaturated polyester resin is a brominated unsaturated polyester obtained by using a maleic acid, fumaric acid or the like as an unsaturated dicarboxylic acid and brominating a divalent alcohol, for example, using dibromoneopentyl glycol. With a vinyl monomer such as styrene.

Examples of the inorganic flame retardant include hydroxides such as aluminum hydroxide, magnesium hydroxide and calcium hydroxide, and antimony oxides such as antimony trioxide and antimony pentoxide. It decomposes and releases water to exhibit an endothermic effect and suppresses combustion, and antimony oxide exhibits an air blocking effect in the presence of bromine to suppress combustion. A preferred inorganic flame retardant is aluminum hydroxide. In particular, a combination of aluminum hydroxide and a small amount of antimony trioxide is preferable because the amount of smoke generated can be reduced. These inorganic flame retardants can be surface-treated with a fat or oil such as coconut oil, a silane coupling agent, or the like, for the purpose of improving dispersibility, improving the leveling property of the molding resin surface, and the like.

The amount of the inorganic flame retardant added is 100
30 to 150 parts by weight, preferably 50 to 7 parts by weight based on parts by weight
When the amount is less than 30 parts by weight, the flame retardancy becomes insufficient, and when the amount exceeds 150 parts by weight, the viscosity of the impregnated resin liquid becomes too high and the workability is lowered.

The above-mentioned impregnated resin is mainly mixed with a brominated unsaturated polyester resin and a non-brominated ordinary unsaturated polyester resin or a phosphorus-containing unsaturated polyester resin as long as the desired flame retardancy can be guaranteed. Can be.

As the fibers of the FRP layers 11 and 13 of the longitudinal fibers and the fibers of the FRP layer 12 of the weft-wound fibers, glass roving or glass yarn can be used.
Glass mats (strands cut to an appropriate length and pressed into a non-woven fabric) are used for the fibers of the P layer 14,
Glass cloth (cloth woven with glass yarn), glass roving cloth (cloth woven with glass roving) and the like can be used. Instead of these glass fiber materials, carbon fiber materials and aramid fiber materials can also be used.

It is preferable to use a flame-retardant polyester non-woven fabric as the base material of the surface layer. In particular, the surface layer of the phosphorus-containing polyester nonwoven fabric combines with oxygen at the time of combustion to form a low heat-generating phosphorus oxide film, thereby contributing to the prevention of thermal decomposition of the resin. Since a saturated polyester resin can be impregnated and cured, it is preferable to use a phosphorus-containing polyester nonwoven fabric.

The dimensions of the above cable protection tube are usually 3 to 6 m in length and 2 to 5 mm in thickness, preferably 3 to 4 mm.

The above-mentioned cable protection tube is usually manufactured by a continuous drawing filament winding method, and as shown in FIG. 2, an uncured multilayer body s ₁ formed on a mandrel 16 is guided to a heating mold 17 ( the tip of the mandrel 16 has reached the outlet of the mold 17), and curing the resin with the shaping in a mold 17, the take-up Lilo - Blank cut by the cutter -19 while taking over the cured molded article s ₂ by Le 18 You can use the method of doing. In FIG. 2, p is a resin bath, 11
1 and 131 are glass rovings for longitudinal fibers.
21 Garasuro for Spiral - Bing, 141 respectively of the glass mat, the take-up Lilo - each material with the take-up of the hardened molded body s ₂ by Le 18 is fed, dipping each resin bath p impregnated, either come up to the vertical direction over the entire circumference of the mandrel 16, or Yokomaki has been resin impregnated multilayer body s ₁ is formed, Sa in the mold inlet to the resin-impregnated multi-layer body s ₁ of the uncured - is a polyester nonwoven fabric 151 is coated for face, resin curing is carried out with shaping between the mold passage, the cured molded article s ₂ take-Lilo - taken care Le 18, further, the fixed-length cut by the cutter -19 To go.

In the above, the surface non-woven fabric 15 covered on the outer surface of the uncured multilayer body s ₁ at the entrance of the mold 17.
1, previously Hitami included the uncured multilayer body s ₁ resin is cured, support by curing of the resin - the face layer, so-called, is integrated formed to generate no resin cured multilayer dry spots.

FIG. 3A shows a joint for a cable protection tube according to the present invention. Like the above-mentioned cable protection tube, an FRP layer of longitudinal fibers and an FRP layer of weft-wound fibers are sequentially arranged from the inside. , A longitudinal fiber FRP layer, a mat or cloth fiber FRP layer, and a resin-impregnated surface layer, and each of the FRP layers and the surface layer impregnated resin contains an inorganic flame-retardant brominated unsaturated. An annular groove 101 is formed on the inner surface of one end by cutting or the like using a polyester resin. Specific examples of the brominated unsaturated polyester resin and the inorganic flame retardant, the amount of the inorganic flame retardant to be added, the base material of each FRP layer and the resin-impregnated surface layer, etc. in the cable protective tube joint are as described above. Same as protection tube.
The dimensions of this cable protection tube joint are usually 250
５００500 mm and a thickness of 5-10 mm.

The joint for a cable protection tube according to the present invention is not limited to the above continuous drawing filament winding method.
Filament winding method (a resin-impregnated fiber material is wound around a rotating mandrel coated with a release agent such as a silicone resin while being traversed, and after winding a predetermined amount, the resin is cured, and then the mandrel is pulled out. Method) or sheet winding method (a method in which a resin glass cloth is wound around a rotating mandrel coated with a release agent such as a silicone resin, and after a predetermined amount is wound, the resin is cured, and then the mandrel is pulled out. ), Etc., can be obtained by cutting the pipe body to a predetermined length and cutting an annular groove in the inner surface of one end.

In order to join a cable protection tube with the joint according to the present invention, as shown in FIG.
The rubber protection tube 3a is attached to the rubber ring 102 inside one end of the joint 10.
(Circular or square cross section, for example, made of butyl rubber)
And the other cable protection tube 3b is connected to the joint 10
Can be adhered to the other end of the cable with an adhesive 103, for example, an epoxy-based adhesive. The inner ends of both cable protection tubes 3a and 3b can be smoothly drawn in. It is preferable to chamfer. Further, it is preferable to provide a gap between the ends of the cable protection tube so that the ends of the cable protection tube do not come into contact with each other even if the cable protection tube extends in summer or the like. The joint structure of the cable protection tube by the joint according to the present invention can be a rubber ring joint system at both ends.

The cable protection tube and the joint according to the present invention are made of a fiber reinforced resin containing a brominated unsaturated polyester resin containing an inorganic flame retardant and impregnated with the resin, and a brominated resin containing an inorganic flame retardant. The unsaturated polyester resin has sufficient flame retardancy, and the surface layer can be uniformly impregnated with the resin without causing dry spots.
Thus, according to the cable protection tube and the joint according to the present invention,
Compared to fiber-reinforced unsaturated polyester tubing, even if exposed to a flame, it can slightly spread the fire of the pipe, and even if it does not impart non-combustibility or high self-extinguishing property to the entire length of the pipe, it will not cause misfire under the bridge. Advantages such as being able to cope with it, eliminating discoloration and deterioration in strength, which are not torn when there is a dry spot on the surface layer in the area exposed to the flame, and allowing continuous use of the cable protection tube without any trouble. Is obtained. This is clear from the test results described below.

[Test] The samples used are as follows. Sample 1 This is a sample of the cable protection tube according to the present invention, which has a structure shown in FIG. 1, and has glass roving for longitudinal fibers and weft-wound fibers, glass mat for mats, and surface layer. Polyester non-woven fabric (thickness 190 μm, fiber amount 4)
7 g / mm ² ), and 100 parts by weight of an aluminum hydroxide surface-treated with coconut oil was added to 100 parts by weight of a brominated unsaturated polyester resin as an impregnated resin, and the viscosity at 25 ° C. was 75%. ~ 85 poise, 12
A resin having a standard gel time of 2.2 minutes at 0 ° C. was used as the impregnating resin, and the mold temperature was 200 ° C. and the drawing speed was 1 by using the continuous drawing filament winding method described above.
m / min. The sample had an outer diameter of 131 mm and a thickness of 3 mm.

Sample 2 The impregnated resin had a viscosity at 25 ° C. of 10 to 60 poise, 120
Sample 1 was the same except that a phenolic resin with a standard gel time of 3 minutes at ° C was used.

Sample 3 A non-brominated ordinary unsaturated polyester having a viscosity of 8 to 12 poise at 25 ° C. and a standard gel time of 4 minutes at 80 ° C. was used. Speed 1m
/ Min, and the same as the sample.

[Test 1] As shown in FIG. 4A, a galvanized steel frame 4 having a U-shaped cross section and a length of 3500 mm (both ends open) was placed on the ground, and a length of 3000 mm was set in the frame.
The height of the sample from the ground is e = 600 mm, and the distance between the tubes is f
Three tubes were arranged in parallel at 200 mm, and one end of the entire tube was ignited with a flame using gasoline as a fire source inside one end of the galvanized iron frame 4 to ignite the tubes. After the ignition, the fire source was removed. The sample and the sample completely self-extinguished within 5 seconds after the removal of the fire source, but the sample did not self-extinguish and completely burned in about 750 seconds.

[Test 2] As shown in (b) of FIG. 4, the height e from the ground was 600 mm and the height g was 800 mm.
Test example 1 in which six tubes are arranged at an interval f = 200 mm between stages and pipes
The self-extinguishing properties were tested as in After ignition, the sample and the sample completely self-extinguished within 10 seconds after removal of the fire source. However, the sample did not extinguish itself, but spread and burned completely in about 600 seconds.

Further, from the appearance inspection with the sample, a dry spot was observed in the sample, and in the portion where the flame was touched, fading of the dry spot was observed. It was in a state that could be used continuously without any.

As is apparent from the test results, the cable conduit according to the present invention can be used even when exposed to a flame.
Since the fire spread of the pipe can be kept to a small extent, it is possible to cope with fire under the bridge without giving the entire length of the pipe non-combustible or high self-extinguishing property, and the surface layer of the part exposed to the flame can be treated. Appearance reduction can be suppressed well, and it can be used continuously without any trouble thereafter. Therefore, if the cable protection tube and the joint according to the present invention are used for a bridge substructure in a cable line, it is possible to prevent fire spread from a fire under a bridge and to provide a stable power supply.
Communication etc. can be guaranteed.

FIG. 5 is a view showing an example of a cable section of a bridge-attached cable using a cable protection tube according to the present invention.
In FIG. 5, A is a bridge. Reference numeral 21 denotes a water surface of the river, and reference numerals 22 and 22 denote ground portions of the river. 3 and 3 are underground pipelines on both sides of the bridge, including steel pipes, concrete pipes,
A resin concrete tube or the like is used. B is a bridge-attached pipeline portion, a is a pipeline portion having a height of 5 m or less from the river ground 22, and a 'is a remaining pipeline portion. In FIG. 5, the height h at the point p ′ is 5 m, and the distance w from the bridge end to the point p is usually within 15 m. A pipe portion a of which the height from the river ground 2 of the bridge-added pipe portion B is 5 m or less is formed by joining a cable protection pipe made of a brominated unsaturated polyester resin according to the present invention with a joint. The remaining pipeline portion a 'of the bridge substructure pipeline portion B is made of fiber reinforced unsaturated polyester tubing (fibers need not be nonflammable, but glass fibers are usually used in terms of cost). It is configured to be joined by a joint.
The length L of the tube material is set to 3 to 6 m in consideration of workability in transportation and work at high places, weight reduction, and the like. For joining of the pipe material by a joint, for example, a structure in which the joint is integrated with one end of the pipe material in advance and the joint and the other end of the mating pipe material are slidably joined via a rubber ring can be used. Pipe section a in which the height of the above-mentioned bridge connecting pipe section B from the river ground 2 is 5 m or less.
Are joints made of a material that is more flame-retardant than glass fiber reinforced unsaturated polyester resin, for example, a fiber reinforced resin joint using a brominated unsaturated polyester resin or a metal (for example, steel) joint. It is preferred to use Fiber reinforced using a brominated unsaturated polyester resin is also used for the joint of the remaining pipeline portion a 'of the bridge extension pipeline portion B and the joint between the pipeline portion a' and the underground pipeline portion 3. Resin joints and metal joints can be used. The pipelines are usually laid in a multi-stage manner. In a bridge attachment part, a multi-stage shelf is assembled in a lower portion of the bridge, and a large number of pipelines are arranged in parallel at each stage of the shelf.

In the above-mentioned bridge-attached cable conduit,
Although the river ground exists on both sides of the river water surface, as shown in FIG. 6, when the river ground 22 exists only on one side of the river water surface 1, the bridge end side portion a on the one-side river ground 22
The fiber-reinforced phenol resin cable protection tube according to the present invention is used for the pipe material (part 5 m or less from the river ground), and the fiber-reinforced unsaturated polyester resin pipe material is used for the other part a '. Can be used. The above pipe section a '
In place of the fiber reinforced unsaturated polyester tube, a fiber reinforced epoxy resin tube or a fiber reinforced vinyl ester resin tube may be used.

[0031]

The cable protection tube and the joint according to the present invention are made of a brominated unsaturated polyester resin to which an inorganic flame retardant has been added. Due to the flame retardancy of the saturated polyester resin and the difficulty of the ignition flame to travel in the horizontal direction, it is possible to self-extinguish the fire by keeping the spread of the fire light. In addition, the surface layer can be in a uniform state without dry spots, avoiding deterioration in appearance and strength due to discoloration in the areas of the dry spots exposed to the flame, and continued use of the pipeline without hindrance it can. In addition, a bridge subduct that can guarantee lightness and corrosion resistance and can withstand long-term use can be constructed with good workability. Therefore, according to the present invention, even if a fire occurs under the bridge, it is possible to easily construct a corrosion-resistant bridge-attached cable conduit portion that can be used continuously while minimizing damage.

[Brief description of the drawings]

FIG. 1 is a view showing a cable protection tube according to the present invention.

FIG. 2 is a view showing a molding apparatus used for manufacturing a cable protection tube according to the present invention.

FIG. 3 is a view showing a cable protection tube joint according to the present invention and a usage form thereof.

FIG. 4 is an explanatory view showing a self-extinguishing test of the cable protection tube according to the present invention.

FIG. 5 is a view showing an example of a cable line for supporting a bridge using a cable protection tube according to the present invention.

FIG. 6 is a view showing an example of a cable line for connecting a bridge using a cable protection tube according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Joint 11 FRP layer of longitudinal fiber 12 FRP layer of weft fiber 13 FRP layer of longitudinal fiber 14 FRP layer of mat or cloth fiber 15 Surface layer

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[Procedure amendment]

[Submission date] August 4, 1998 (1998.8.4)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0022

[Correction method] Change

[Correction contents]

[Test] The samples used are as follows. Sample 1 This is a sample of the cable protection tube according to the present invention, which has a structure shown in FIG. 1, and has glass roving for longitudinal fibers and weft-wound fibers, glass mat for mats, and surface layer. Polyester non-woven fabric (thickness 190 μm, fiber amount 4)
7 g / m ² ), and 100 parts by weight of brominated unsaturated polyester resin and 100 parts by weight of aluminum hydroxide surface-treated with coconut oil were added as the impregnated resin. 75-85 poise, 120
A resin having a standard gel time of 2.2 minutes at 200 ° C. was used as the impregnating resin, and the mold temperature was 200 ° C. and the drawing speed was 1 m using the continuous drawing filament winding method described above.
/ Min. The sample had an outer diameter of 131 mm and a thickness of 3 mm.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Mitsuhiro Kitajima 2-7-1 Ninomiya, Fukui City, Fukui Prefecture Inside Nitto Shinko Co., Ltd. (72) Inventor Tomio Kawabe 2-7-1 Ninomiya, Fukui City, Fukui Prefecture Nitto Shinko F term in the company (reference) 5G367 BA03 BB14 5G369 AA04 BA04 BB03 DC06

Claims (5)

[Claims] 1. A cable protective tube made of a fiber-reinforced synthetic resin using a brominated unsaturated polyester resin as a main component resin of an impregnated resin. 2. The cable protective tube according to claim 1, wherein an inorganic flame retardant is added to the impregnated resin. 3. The case according to claim 1, wherein a flame-retardant polyester nonwoven fabric is used as a fiber material for the surface layer.
Bull protection tube. 4. A joint for a cable protective tube made of a fiber-reinforced synthetic resin using a brominated unsaturated polyester resin as a main component resin of an impregnating resin. 5. The cable protection tube in a bridge substructure portion according to claim 1.
A cable conduit using the cable protective tube according to any one of claims 1 to 3.