JP4002118B2 - Joint structure of fireproof double-layer pipe - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a joint structure of a fire-resistant two-layer pipe comprising an inner pipe and a fire-resistant and heat-insulating outer pipe covering the inner pipe, and more particularly, a special packing material as a joint material for the joint. The present invention relates to the joint structure of the fireproof double-layer pipe straight pipe and the fireproof double-layer pipe joint used.
[0002]
[Prior art]
In general, a fire-resistant double-layer pipe in which an inner pipe made of a synthetic resin such as hard vinyl chloride is coated with an outer pipe having fire resistance and heat insulation, for example, a fiber-reinforced mortar cladding pipe, is an inner pipe made of a synthetic resin. The inner peripheral surface is smooth, excellent in chemical resistance and water resistance, and covered with an outer pipe, so that it has excellent fire resistance and heat insulation, so it can be used as a water supply pipe, drain pipe, ventilation vent pipe and distribution pipe for buildings. Widely used.
[0003]
A joint structure for connecting such fireproof two-layer pipes will be described with reference to FIG.
FIG. 4 is a cross-sectional view showing a joint for connecting a pair of fireproof double-layer pipe straight pipes (21) to each other by a fireproof double-layer pipe joint (24). The fireproof two-layer pipe straight pipe (21) has fire resistance and heat insulating properties such as an inner pipe (22) made of a synthetic resin, for example, hard vinyl chloride, and a fiber-reinforced mortar clad pipe covering the inner pipe (22). It consists of an outer pipe (23), and a fireproof two-layer pipe fitting (24) is also made of synthetic resin, for example, an inner pipe (25) made of hard vinyl chloride, and a fiber reinforced mortar cladding pipe covering the inner pipe (25), etc. The outer tube (26) having the fire resistance and heat insulation properties. The inner diameter of the inner pipe (25) of the refractory double-layer pipe fitting (24) is such that the end (22a) of the inner pipe (22) of the refractory double-layer pipe straight pipe (21) can be fitted therein. An annular protrusion (25b) is provided in the central portion of the peripheral surface to contact the opening edge (22a) of the inner pipe (22) of the fire-resistant double-layer pipe (21) inserted to determine the insertion depth position. It has been.
[0004]
The refractory double-layer pipe straight pipe (21) is connected to the inner pipe (22) protruding outward from the opening edge (23b) of each outer pipe (23) of the refractory double-layer pipe straight pipe (21) to be connected. Adhesive is applied in advance to the end portions (22a) of these, and these end portions (22a) are respectively inserted and fitted from the opening end edge (25a) of the inner pipe (25) of the fireproof double-layer pipe fitting (24), This is done by bringing the open end edge (23b) of the outer pipe (23) of the refractory double-layer pipe straight pipe (21) into contact with the open end edge (26b) of the outer pipe (26).
[0005]
Next, the opening edge (23b) of the outer pipe (23) of the refractory double-layer pipe straight pipe (21) and the opening edge (26b) of the outer pipe (26) of the refractory double-layer pipe fitting (24) In the contact portion, a slight gap is generated due to processing accuracy when the outer tube (23) of the fireproof double-layer tube (21) is cut, and the outer tube (23) and the outer tube (26). Since the material is discontinuous, the dry curable joint material (27) mainly made of sodium silicate or cement is stretched into a string shape, and the opening edge of the outer pipe (23) of the fire-resistant double-layer pipe (21) A joint treatment is performed by a wet joint method in which the cover is wound around a contact portion between (23b) and the opening edge (26b) of the outer pipe (26) of the fireproof double-layer pipe joint (24).
[0006]
As another joint treatment, a dry joint method shown in FIG. 5 is applied. In FIG. 5, the cross section corresponds to the step between the outer peripheral surface of the outer pipe (23) of the refractory double-layer pipe straight pipe (21) and the outer peripheral surface of the outer pipe (26) of the refractory double-layer pipe fitting (24). The outer pipe of the outer pipe (23) of the fire-resistant double-layer pipe straight pipe (21) and the outer pipe of the fire-resistant double-layer pipe joint (24) have a bent portion (31a) bent in a substantially staircase shape. The strip-shaped metal joint cover (31) having the crimping surfaces (31b) and (31c) respectively in contact with the outer peripheral surface of (26) is connected to the outer peripheral surface of the outer tube (23) of the refractory double-layer pipe straight pipe (21). Wrap around the outer pipe (26) of the fire-resistant double-layer pipe fitting (24) and wind it, and tighten the crimping faces (31b) and (31c) between both ends with screws, nuts, etc. It is to wear.
[0007]
Furthermore, as another joint treatment, Japanese Patent No. 2656726 discloses a fire-resistant double-layer pipe comprising an inner pipe and a fire-resistant and heat-insulating outer pipe covering the inner pipe, and an inner pipe and the inner pipe. In the joint structure of a fire-resistant double-layer pipe that connects a pipe joint made of an outer pipe having fire resistance and heat insulation to cover, the inner pipe end of the fire-resistant double-layer pipe and the inner pipe end of the pipe joint to be connected to each other Between the outer end of the outer tube of the refractory double-layer tube and between the outer end of the outer tube of the refractory double-layer tube and the open end of the outer tube of the pipe joint. An annular packing made of non-flammable inorganic heat-insulating fibers that allows relative displacement between the outer pipe of the pipe joint and the outer pipe of the pipe joint and surrounds the combined inner pipe and an open end edge of the outer pipe of the refractory double-layer pipe Joining a fire-resistant double-layer pipe characterized by being inserted in a compressed state by the opening edge of the outer pipe of the pipe joint Structure is disclosed.
[0008]
As yet another joint treatment, the present applicant has disclosed, in Japanese Patent Application No. 2001-271873, a fireproof double-layered pipe composed of an inner pipe and a fireproof and heat insulating outer pipe covering the inner pipe, an inner pipe and the inner pipe and the inner pipe. In the joint structure of a refractory double-layer pipe that connects a pipe joint composed of a fire-resistant and heat-insulating outer pipe covering the inner pipe, the inner pipe end of the refractory double-layer pipe to be connected to each other and the inside of the pipe joint The pipe end is fitted and joined, and the joined inner pipe is connected between the opening edge of the outer pipe of the fireproof double-layer pipe and the opening edge of the outer pipe of the pipe joint facing the opening edge. The joint structure of the fire-resistant double-layer pipe characterized by interposing an annular packing made of a heat-expandable fire-resistant material surrounding the tube is proposed.
[0009]
That is, the joint joint processing described in the above-mentioned Japanese Patent No. 2656726 and Japanese Patent Application No. 2001-271872 uses an annular packing material (33) made of an inorganic heat insulating fiber or a thermally expandable refractory material as shown in FIG. The open end edge (23b) of the outer pipe (23) of the fireproof double-layer pipe straight pipe (21), and the open end edge (26b) of the outer pipe (26) of the fireproof double-layer pipe joint (24) to be connected This is a dry joint method.
[0010]
[Problems to be solved by the invention]
The conventional techniques as described above are based on the use of inorganic materials having nonflammability and fire resistance as joint treatment materials, and have the following problems. That is, in joint treatment by the above-mentioned wet joint method, the joint is kept perfectly without gaps for a certain period after construction, and smoke spreads from the fire site to other sections through a fireproof double-layer pipe in the event of a fire. However, the joint material applied to the contact portion between the fireproof double-layer pipe straight pipe and the fireproof double-layer pipe joint is shrunk as it hardens over time, and cracks and delamination occur, causing building shaking, etc. The external force may cause the joint material to fall off, and it is necessary to repair and maintain the performance each time. In addition, deterioration due to carbonation of joints may be caused, and there may be a problem that it is difficult to ensure a function as a stable joint treatment over a long period of time.
[0011]
In joint processing using a metal joint cover of the dry joint method, the shape and shape of the joint cover is set in advance. If it is deformed into an elliptical shape, it will be difficult to install, and it will be easy to create a gap. It will require a lot of work to eliminate the gap, and it will be made of metal. When it is used, the heat insulation performance may not be sufficient, and condensation may cause the joint cover to corrode, resulting in a problem that it is difficult to ensure a stable joint treatment function over a long period of time.
[0012]
Furthermore, since the former two joint treatments are performed after the piping work to the building is completed, the work space is limited, the work is troublesome, the uniform joint treatment function is difficult to obtain, and the construction period is prolonged. Will be invited. In the renovation work, the work space is limited, and extra work for expanding the work space is required for the renovation work.
[0013]
In addition, in joint processing that uses an annular packing material made of inorganic heat insulating fibers or an annular packing material made of a heat-expandable refractory material, the joint treatment is stable over a long period of time. It is possible to simplify the work, and shows a sufficient effect in the joint processing method of the fire-resistant double-layer pipe straight pipe and the fire-resistant double-layer pipe joint, but its composition lacks elasticity, The fact is that a gap is generated due to insufficient cutting accuracy of the fire-resistant double-layer pipe in the field construction, and it is the actual situation that a great effort is being made in the gap filling work.
[0014]
In other words, if joint treatment is not sufficient, during the fire, from the fire site to other compartments, through the gap between the inner and outer pipes of the refractory double-layer pipe and through the gap between the inner and outer pipes of the refractory double-layer pipe joint Smoke flows in, making it difficult to secure the safety of other compartments, and the effect as a joint material cannot be found.
[0015]
Accordingly, an object of the present invention is to provide a joint structure for a refractory double-layer pipe capable of preventing smoke generated at the fire site in the early stage of fire from being diffused to other sections through the refractory double-layer pipe. It is in.
[0016]
[Means for Solving the Problems]
That is, the joint structure of the fire-resistant double-layer pipe of the present invention includes a fire-resistant double-layer pipe straight pipe comprising an inner pipe and an outer pipe having fire resistance and heat insulation covering the inner pipe, and the inner pipe and the inner pipe. In a joint structure of a fire-resistant double-layer pipe connecting a fire-resistant double-layer pipe joint comprising an outer pipe having fire resistance and heat insulation, the joint structure includes the fire-resistant double-layer pipe straight pipe to be connected to each other, and The refractory double-layer pipe joint is fitted and coupled to the refractory double-layer pipe straight pipe, and has an opening edge of the outer pipe having fire resistance and heat insulation of the straight pipe, and the refractory double-layer pipe facing the opening edge. The outer edge of the outer pipe having fire resistance and heat insulation of the pipe joint is sealed with an annular packing material, and the annular packing material is a material mainly composed of polyolefin foam, foamed polyethylene or foamed polypropylene, Or polystyrene foam, urethane foam Characterized by comprising of polyethylene foam, polypropylene, rubber and one selected from the group consisting of synthetic rubber or two or more combustible materials.
[0017]
Moreover, the joint structure of the fireproof two-layer pipe of the present invention is characterized in that the expansion ratio of the annular packing material is 10 to 50.
[0018]
Furthermore, the joint structure of the fireproof two-layer pipe according to the present invention is characterized in that the annular packing material is constituted by a plurality of packing members divided in an arc shape.
[0019]
In addition, the joint structure of the fire-resistant double-layer pipe of the present invention is a fire-resistant double-layer pipe straight pipe and a fire-resistant double-layer pipe joint whose inner pipe is made of a synthetic resin. The outer pipe having fire resistance and heat insulation of the pipe joint is a fiber reinforced mortar cladding pipe.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, one embodiment of the joint structure of the fireproof double-layered pipe of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view for explaining a joint structure of a fireproof double-layer pipe according to the present invention, in which a pair of fireproof double-layer pipes (1) are connected to each other via a fireproof double-layer pipe joint (5). FIG. 2 is a perspective view showing an annular packing material (9) used in the joint structure of the refractory double-layer pipe of FIG. Here, the fireproof two-layer pipe straight pipe (1) is, for example, an inner pipe (2) made of a synthetic resin such as hard vinyl chloride, and has fire resistance and heat resistance covering the inner pipe (2), for example, fiber An outer tube (4) such as a reinforced mortar cladding tube is formed, and a gap (3) is formed between the inner tube (2) and the outer tube (4). The gap (3) is provided to absorb expansion of the inner pipe (2) due to heat.
[0021]
The fire-resistant double-layer pipe joint (5) for connecting the fire-resistant double-layer pipe straight pipe (1) to each other is also made of an inner pipe made of synthetic resin such as hard vinyl chloride (6 ) And an outer tube (8) such as a fiber-reinforced mortar cladding tube covering the inner tube (6), and a gap (7) is formed between the inner tube (6) and the outer tube (8). Has been. The inner pipe (6) of such a fireproof two-layer pipe joint (5) has an inner diameter into which the end (2a) of the inner pipe (2) of the fireproof two-layer pipe straight pipe (1) can be fitted, And in the center part of the inner peripheral surface of the inner pipe (6), the inner pipe (2) of the fire-resistant double-layer pipe straight pipe (1) fitted into the inner pipe (6) of the fire-resistant double-layer pipe joint (5) An annular projection (6b) for determining the position of the fitting depth is provided, and the end edge (2b) of the inner tube (2) to be fitted is brought into contact with both sides of the annular projection (6b). Is formed.
[0022]
In order to connect the refractory double-layer pipe straight pipe (1) to be connected to each other via the refractory double-layer pipe joint (5), the outer pipe (4) of the refractory double-layer pipe straight pipe (1) is previously connected. An annular packing material (9) having a shape as shown in FIG. 2 is attached to the end (2a) of the inner pipe (2) projecting a defined length so as to surround the outer periphery thereof, Adhesive is applied to the outer peripheral surface of the end (2a) of the pipe (2), and the end (2a) is connected to both ends of the inner pipe (6) of the fireproof double-layer pipe joint (5) (6a). The inner pipe (2) of the refractory double-layer pipe straight pipe (1) and the refractory double-layer pipe joint (5) are inserted and fitted, and the opening edge (2b) is brought into firm contact with the annular protrusion (6b). ) And the inner pipe (6).
[0023]
Here, the annular packing material (9) was selected from the group consisting of polyolefin foam, foamed polyethylene or foamed polypropylene, or polystyrene foam, urethane foam, polyethylene foam, polypropylene, rubber and synthetic rubber. It consists of one or more combustible materials .
[0024]
Further, the annular packing material (9) preferably has an expansion ratio in the range of 10 to 50, preferably 30 to 50. In addition, it is not preferable that the expansion ratio is less than 10 or exceeds 50 because the smoke-proof performance required at the joint between the fireproof double-layer pipe straight pipe and the fireproof double-layer pipe joint cannot be obtained.
[0025]
When the annular packing material (9) is mounted, the outer tube (4) of the fireproof two-layer pipe straight pipe (1) is used for the thickness of the annular packing material (9) by utilizing the compression / restoration property of the annular packing material (9). Cut and apply to dimensions that compress in the range of 1% to 80% in the direction. Thereby, the clearance (3) between the inner pipe (2) and the outer pipe (4) of the fire-resistant double-layer pipe straight pipe (1), and the inner pipe (6) and the outer pipe of the fire-resistant double-layer pipe joint (5) The gap (7) with (8) can be sealed.
[0026]
With this joint structure, it is possible to prevent the smoke generated at the fire site in the early stage of the fire from being diffused to other compartments through the fireproof double-layer pipe. The annular packing material (9) used in the present invention is made of a flammable material as described above. However, according to the knowledge of the present inventors, the refractory double-layer tube itself is not heated by the flame. Before the exposure, the movement of the smoke begins and it is effective to make the annular packing material (9) with the above-mentioned material when it is intended to surely prevent the emission of smoke at the beginning of the fire. It turned out to be.
[0027]
In addition, the annular packing material used for the joint structure of the fireproof two-layer pipe of the present invention is not limited to the one having an integral shape as shown in FIG. A plurality of divided packing members may be used to construct a ring.
[0028]
3 is a cross-sectional view showing another embodiment of the joint structure of the fire-resistant double-layer pipe of the present invention, and a fire-resistant double-layer pipe joint having a shape different from that of the fire-resistant double-layer pipe joint shown in FIG. 1 is used. Is. That is, as shown in FIG. 3, the fire-resistant double-layer pipe joint (10) to which the fire-resistant double-layer pipe straight pipe (1) is connected is a so-called substantially T-shaped fire-resistant double-layer pipe joint, Fire resistance and heat insulation superposed so as to cover the inner pipe (11) formed with a gap (12) between the inner pipe (11) made of a synthetic resin such as And an outer tube (13) made of a fiber-reinforced mortar-coated tube or the like. The inner pipe (11) and the outer pipe (13) have a substantially T-shape, and the inner pipe (11) is an end portion of the inner pipe (2) of the refractory double-layer pipe straight pipe (1). (2a) has an end portion (11a) having an inner diameter into which the open end edge (11) of the inner tube (2) of the refractory double-layer pipe straight pipe (1) ( A step portion (11a) for determining the fitting depth of the inner tube (2) is formed by abutting 2b). The outer tube (13) has substantially the same shape as the inner tube (11) and covers the inner tube (11). A gap (12) is provided between the inner tube (11) and the outer tube (13) to absorb expansion of the inner tube (11) due to heat.
[0029]
The connection between the fire-resistant double-layer pipe straight pipe (1) and the fire-resistant double-layer pipe joint (10) protrudes from the outer pipe (4) of the fire-resistant double-layer pipe straight pipe (1) by a predetermined length, as described above. An end portion (2a) having an annular packing material (9) attached to the end portion (2a) of the inner tube (2) and an adhesive applied to the outer peripheral surface is connected to the inner tube (11) of the refractory double-layer pipe fitting (10). ), The inner tube (2) and the inner tube (11) are integrated, and the annular packing material (9) is opened at the open end of the outer tube (4) of the refractory double-layer tube (1). The fire-resistant double-layer pipe straight pipe (1) is interposed between the edge (4b) and the open end edge (13b) of the outer pipe (13) of the fire-resistant double-layer pipe joint (10). And the fireproof two-layer pipe joint (10) can be integrally connected. By interposing the annular packing material (9), it is possible to prevent the smoke generated at the fire site in the early stage of the fire from being diffused to other sections through the fireproof double-layer pipe.
[0030]
【Example】
EXAMPLE In order to evaluate the joint structure of the fireproof two-layer pipe according to the present invention, a heating test using a heating test body as shown in FIG. 6 was conducted. FIG. 7 is a partially enlarged view thereof.
First, in a fireproof double-layer pipe composed of a hard vinyl chloride inner pipe and an outer pipe of a fiber-reinforced mortar cladding pipe covering the inner pipe, a fireproof double-layer pipe straight pipe having a nominal diameter of 150 mm and a fireproof connecting the same Using a DS socket and CO (cleaning port), which are two-layer pipe joints, the inner pipes are fitted together using a rubber-based adhesive, and the foamed polyethylene is the main component in the contact part between the outer pipes. The heating test body shown in FIG.
[0031]
When the heating test body was subjected to a heating test for 2 hours at the partition penetration portion based on ISO834, the following test results were obtained.
In the test, the expansion ratio of the annular packing material used for the joint portion of the fireproof double-layered tube is 30 times the expansion ratio within the range of claim 2 of the present invention, the thickness is 10 mm, the outer diameter is 200 mm, and the inner diameter is 164 mm. An annular packing material (Invention Example 1) and an expanded packing material made of polyethylene foam having an expansion ratio of 8 times, thickness 10 mm, outer diameter 200 mm, and inner diameter 164 mm outside the scope of Claim 2 of the present invention (Invention Example 2) It was done by attaching and comparing.
[0032]
First, 9 minutes after the start of heating, in both the inventive examples 1 and 2, the CO (cleaning port) at the end of the refractory double-layer pipe joint in the heating side space dropped out. Twelve minutes after the start of heating, smoke was generated from the annular packing material attached to the refractory double-layer pipe straight pipe and the refractory double-layer pipe joint CO (cleaning port) in the non-heating side space of the present invention example 2. Furthermore, after 13 minutes, the fireproof double-layer pipe fitting DS socket in the heating side space dropped out in both the inventive examples 1 and 2. 35 minutes after the start of heating, smoke was generated from the annular packing material attached to the refractory double-layer pipe straight pipe and the refractory double-layer pipe joint DS socket in the non-heated space of Example 2 of the present invention. On the other hand, in the example 1 of the present invention, no smoke was generated in the non-heated space even after 120 minutes from the start of heating, and no abnormality was observed.
[0033]
As described above, the joint structure of the fireproof two-layer pipe according to the present invention can prevent the diffusion of smoke to other sections through the fireproof double-layer pipe in the initial stage of the fire by attaching the annular packing material. It can be seen that by using an annular packing material having a suitable expansion ratio as defined in claim 2, it is possible to further prevent smoke from being diffused to other compartments through the fireproof double-layer pipe.
[0034]
【The invention's effect】
According to the joint structure of the fireproof two-layer pipe of the present invention, it is possible to prevent the smoke generated at the fire site in the early stage of the fire from being diffused to other sections through the fireproof two-layer pipe. Is.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing one embodiment of a joint structure of a fireproof two-layer pipe according to the present invention.
FIG. 2 is a perspective view showing an embodiment of an annular packing material used in the joint structure of a fireproof two-layer pipe of the present invention.
FIG. 3 is a cross-sectional view showing another embodiment of the joint structure of the fireproof two-layer pipe of the present invention.
FIG. 4 is a cross-sectional view illustrating a joint structure of a conventional fireproof double-layer tube.
FIG. 5 is a cross-sectional view illustrating another joint structure of a conventional fireproof double-layer tube.
FIG. 6 is a schematic view of a heated test specimen used for evaluating the joint structure of a refractory double-layer pipe according to the present invention.
7 is a partially enlarged view of the heating test body shown in FIG. 6. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Fireproof two-layer pipe straight pipe 2 Inner pipe 2a End part 4 Outer pipe 4a End part 4b Open edge 5 Fireproof double-layer pipe joint 6 Inner pipe 6a End part 8 Outer pipe 8a End part 8b Open edge 9 Annular packing material DESCRIPTION OF SYMBOLS 10 Fireproof two-layer pipe pipe joint 11 Inner pipe 11a edge part 13 Outer pipe 13a edge part 13b Open edge

Claims (4)

A refractory two-layer pipe straight pipe comprising an inner pipe and a fire-resistant and heat-insulating outer pipe covering the inner pipe, and a fire-resistant two-layer pipe comprising a fire-resistant and heat-insulating outer pipe covering the inner pipe and the inner pipe. In the joint structure of the refractory two-layer pipe that connects the layer pipe joint, the joint structure fits and connects the refractory double-layer pipe straight pipe and the refractory two-layer pipe joint to be connected to each other, An opening edge of the outer pipe having fire resistance and heat insulation of the fireproof double-layer pipe straight pipe, and an opening edge of the outer pipe having fire resistance and heat insulation of the fireproof double-layer pipe joint facing the opening edge The annular packing material is made of polyolefin foam, foamed polyethylene or foamed polypropylene, or polystyrene foam, urethane foam, polyethylene foam, polypropylene. Joint structure of the refractory bilayer tubes, characterized in that consists of a material of one or more combustible selected from the group consisting of rubber and synthetic rubber.   The joint structure of a fireproof two-layer pipe according to claim 1, wherein the annular packing material has an expansion ratio of 10 to 50.   The joint structure of a refractory double-layer pipe according to claim 1 or 2, wherein the annular packing material is constituted by a plurality of packing members divided in an arc shape. A tube refractory bilayer tube straight pipe and fire bilayer tube fitting inner tube is made of synthetic resin, the outer tube is fiber-reinforced with a refractory and heat-insulating refractory bilayer tube straight pipe and fire bilayer fittings The joint structure of a fireproof two-layer pipe according to any one of claims 1 to 3, which is a mortar cladding pipe.

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