JP7780488B2 - Drainage manifold joint - Google Patents

Description

The present invention relates to a joint.

BACKGROUND ART Conventionally, structures for realizing fire resistance in resin drainage manifold joints have been known, as described in, for example, Patent Documents 1 and 2 below.
Patent Document 1 describes a drainage pipe joint that penetrates the floor slab of a building from top to bottom. In this structure, a pipe made of a heat-expandable fire-resistant material is placed inside the part where the drainage standpipe penetrates the floor slab, surrounding the entire periphery of the penetration part.
Patent Document 2 describes a structure in which a drain pipe joint consisting of an upper body and a lower body penetrates a floor slab. In this structure, an interior member made of a thermally expansive material that expands due to the heat of a fire is provided inside the drain pipe joint. A plurality of blade members called swirl guides are formed on the inner periphery of this interior member, which can swirl the drain water while reducing the flow rate of the drain water as it flows down.

JP 2014-98305 A JP 2015-175187 A

In the structure described in Patent Document 1, a pipe made of a heat-expandable fire-resistant material expands due to the heat of a fire, blocking the drainage pipe and thereby blocking the flow of flames, smoke, etc.
In the structure described in Patent Document 1, a swirl vane for creating a swirling flow of wastewater is provided inside the drainage pipe joint, so the installation position of the heat-expandable fire-resistant pipe and the installation position of the swirl vane must be offset in the vertical direction. This is because if an attempt is made to block the pipe at the swirl vane, the swirl vane may get in the way and interfere with smooth blockage of the pipe.

However, due to the variety of slab thicknesses and other conditions at the actual installation location of the joint assembly, there was a problem in that it was not possible to embed a pipe made of heat-expandable fire-resistant material in the slab and then position the swirl vane below the slab.
For example, the thickness of a typical slab varies widely, ranging from about 150 to 300 mm, and the thickness of the slab varies depending on the installation environment of the collective joint, so there was a problem in that it was difficult to apply the structure described in Patent Document 1 to all installation environments.

In the structure described in Patent Document 2, in order to achieve fire resistance, it was necessary to install a swirl vane large enough to block the pipe. However, when the slab is thin, the lower part of the joint assembly is not embedded in the slab, so if a fire breaks out on the floor below, the lower part of the joint may burn down along with the swirl vane, and in some cases, fire resistance may not be achieved.

The present invention was made in consideration of the above-mentioned circumstances, and aims to provide a joint that can reliably exhibit fire resistance even in slabs of various thicknesses and can be implemented at low cost.

In order to solve the above problems, the present invention proposes the following aspects.
"1" The joint of this embodiment is a collective joint comprising an upper connecting pipe, an intermediate pipe connected to the upper connecting pipe, and a lower connecting pipe connected to the intermediate pipe, characterized in that the intermediate pipe contains a heat-expandable fire-resistant material and the height of the intermediate pipe is 150 mm or less.

In a structure in which the lower end of the upper connecting pipe and the upper end of the lower connecting pipe are inserted into a through hole in the floor slab and the through hole is filled with filler material, the intermediate pipe connecting the lower end of the upper connecting pipe and the upper end of the lower connecting pipe contains a heat-expandable fire-resistant material.
In the event of a fire, if the slab and the area around the through-hole are heated by flames or smoke, the heat-expandable fire-resistant material contained in the intermediate pipe will expand and block the connection between the upper and lower connecting pipes, preventing flames and smoke from the floor below from spreading to the floors above, thereby preventing the spread of fire.

If the height of the intermediate pipe is 150 mm or less, the floor slab thickness can be a wide variety of thicknesses ranging from 150 to 300 mm, and even in different installation environments, the intermediate pipe can be reliably positioned within the floor slab penetration hole, ensuring a reliable fire spread prevention effect. For this reason, the structure of this embodiment is highly versatile and can be widely applied to any building with a standard slab thickness.

If the slab and the area around the through-hole are heated by flames and smoke during a fire, the lower connecting pipe will melt away due to the heat of the fire. Even if the lower connecting pipe melts away, the intermediate pipe will expand and block the through-hole, reliably preventing the flames and smoke from reaching the upper floors and preventing the fire from spreading.
The structure of this embodiment can be realized simply by adopting a structure including a heat-expandable refractory material in the intermediate tube, so there is no need to arrange any additional new components, and it has the characteristic of being easy to implement at low cost.

"2" The fitting of this embodiment is a fitting comprising an upper connecting pipe, an intermediate pipe connected to the upper connecting pipe, and a lower connecting pipe connected to the intermediate pipe, characterized in that a fire-resistant layer containing a thermally expandable fire-resistant material is provided on the outer periphery of the lower end of the upper connecting pipe and the outer periphery of the upper end of the lower connecting pipe, which correspond to the periphery of the intermediate pipe, and the height of the fire-resistant layer is 150 mm or less.

When the lower end of the upper connector and the upper end of the lower connector pipe are inserted into the through-hole in the floor slab and the through-hole is filled with filler, a fire-resistant layer containing a heat-expandable fire-resistant material is provided around the outer periphery of the part where the lower end of the upper connector pipe and the upper end of the lower connector pipe are connected. When the slab and the area around the through-hole are heated by flames or smoke during a fire, the connection between the upper connector pipe and the lower connector pipe softens, and the heat-expandable fire-resistant material contained in the fire-resistant layer expands, sealing off the connection between the upper connector pipe and the lower connector pipe. This prevents flames and smoke from the floor below from spreading to the floor above, effectively preventing the spread of fire.

If the height of the fire-resistant layer is 150 mm or less, the fire-resistant layer can be reliably placed within the floor slab through-holes, even in a variety of different installation environments with floor slab thicknesses ranging from 150 to 300 mm, ensuring a reliable fire prevention effect. For this reason, the structure of this embodiment is highly versatile and can be widely applied to any building with a standard slab thickness.

If the slab and the area around the through-hole are heated by flames and smoke during a fire, the lower connecting pipe will melt away due to the heat of the fire. Even if the lower connecting pipe melts away, the intermediate pipe will expand and block the through-hole, reliably preventing the flames and smoke from reaching the upper floors and preventing the fire from spreading.
The structure of this embodiment can be realized simply by employing a fire-resistant layer containing a heat-expandable fire-resistant material on the outer periphery of the joint between the pipes, so there is no need to place any additional components, and it has the characteristic of being easy to implement at low cost.

"3" In this embodiment, the lower end of the upper connecting pipe and the upper ends of the intermediate pipe and lower connecting pipe are components that are placed within the through-hole in the floor slab, and it is preferable that a connecting pipe section that connects to the intermediate pipe is formed on the upper side of the lower connecting pipe, and a tapered inclined pipe section is formed on the lower side of the lower connecting pipe, and that the entire connecting pipe section and the upper part of the inclined pipe section are placed within the through-hole in the floor slab.

If the entire connecting pipe section and the upper part of the inclined pipe section are placed within the slab penetration hole, the intermediate pipe containing the heat-expandable fire-resistant material or the fire-resistant layer will be securely embedded within the slab penetration hole. Therefore, if the slab and the area around the penetration hole are heated by flames or smoke during a fire, the heat-expandable fire-resistant material contained in the intermediate pipe or fire-resistant layer will expand reliably within the penetration hole, reliably sealing off the pipe connection within the penetration hole. Furthermore, if the tapered inclined pipe section is embedded in sound-proofing material within the penetration hole, the inclined pipe section with its sloped surface will be supported by the filling material. This combination ensures fire resistance by preventing the spread of fire.

"4" In this embodiment, it is preferable that the outer diameter of the lower end of the connecting pipe section is larger than the outer diameter of the upper end of the inclined pipe section, and that a peripheral step is formed at the boundary between the connecting pipe section and the inclined pipe section.

By forming a peripheral step at the lower end of the connecting pipe, if the heat-expandable fire-resistant material contained in the intermediate pipe or fire-resistant layer expands during a fire, the peripheral step will reliably catch on the filler material filling the through-hole, preventing the lower connecting pipe from falling. This ensures that the heat-expandable fire-resistant material can reliably block the pipe connection section inside the through-hole, ensuring fire resistance.

"5" In this embodiment, when the lower end of the upper connecting pipe and the upper ends of the intermediate pipe and lower connecting pipe are placed within a through-hole in the floor slab, it is preferable to fill them with filler material so as to surround them.

By filling the through-hole with filler, sound insulation in the through-hole area can be improved. It also prevents the lower connecting pipe from falling out of the through-hole in the event of a fire due to premature melting.

"6" In this embodiment, it is preferable that a swirl vane is provided inside the upper connecting pipe and above the intermediate pipe.

The presence of swirl vanes above the intermediate pipe allows the intermediate pipe or fireproof layer, which contains a thermally expandable fireproof material, to expand at the joint between the pipes in the slab penetration hole, and when the pipe joint is closed, the swirl vanes do not interfere with this expansion. This allows the penetration hole to be closed reliably and quickly, thereby achieving fire resistance.

"7" The fitting of this embodiment is a fitting comprising an upper connecting pipe and a lower connecting pipe connected to the upper connecting pipe, characterized in that a fire-resistant layer containing a thermally expandable fire-resistant material is provided around the portion where the upper connecting pipe and the lower connecting pipe are connected, and the height of the fire-resistant layer is 150 mm or less.

When the lower end of the upper connector and the upper end of the lower connector pipe are inserted into the through-hole in the floor slab and the through-hole is filled with filler, a fire-resistant layer containing a heat-expandable fire-resistant material is provided around the outer periphery of the part where the lower end of the upper connector pipe and the upper end of the lower connector pipe are connected. When the slab and the area around the through-hole are heated by flames or smoke during a fire, the connection between the upper connector pipe and the lower connector pipe softens, and the heat-expandable fire-resistant material contained in the fire-resistant layer expands, sealing off the connection between the upper connector pipe and the lower connector pipe. This prevents flames and smoke from the floor below from spreading to the floor above, effectively preventing the spread of fire.

If the height of the fire-resistant layer is 150 mm or less, the fire-resistant layer can be reliably placed within the floor slab through-holes, even in a variety of different installation environments with floor slab thicknesses ranging from 150 to 300 mm, ensuring a reliable fire prevention effect. For this reason, the structure of this embodiment is highly versatile and can be widely applied to any building with a standard slab thickness.

If the slab and the area around the through-hole are heated by flames and smoke during a fire, the lower connecting pipe will melt away due to the heat of the fire. Even if the lower connecting pipe does melt away, the fire-resistant layer will expand and block the through-hole, reliably preventing the flames and smoke from reaching upper floors and preventing the fire from spreading.
The structure of this embodiment can be realized simply by employing a fire-resistant layer containing a heat-expandable fire-resistant material on the outer periphery of the joint between the pipes, so there is no need to place any additional components, and it has the characteristic of being easy to implement at low cost.

The present invention provides a joint that can be applied to various common slab thicknesses, reliably exhibits fire resistance, and can be implemented at low cost.

1 is a cross-sectional view showing an example of a fire-resistant structure in which a joint according to an embodiment of the present invention is installed in a through hole in a slab. FIG. FIG. FIG. 2 is a development view showing the component configuration of the joint shown in FIG. 1 . FIG. 4 is a cross-sectional view showing a joint according to a second embodiment of the present invention. FIG. 10 is a cross-sectional view showing a joint according to a first modified example of the second embodiment of the present invention. FIG. 10 is a cross-sectional view showing a joint according to a second modified example of the second embodiment of the present invention.

Hereinafter, an example of a fire-resistant structure in which a joint according to one embodiment of the present invention is applied to a through-hole in a slab will be described with reference to FIGS. 1 to 3.
The fire-resistant joint structure 1 according to this embodiment is used for drainage of a building, and is applied to a through hole H formed in a floor slab S.
In the embodiment shown in Fig. 1, a first vertical pipe P1 of an upper floor is provided above a through hole H formed in a floor slab S, and a second vertical pipe P2 of a lower floor is provided below the through hole H. As shown in Figs. 1 and 2, the fire-resistant structure 1 of a joint according to this embodiment includes a drainage collection joint (joint) 10.

The drainage manifold 10 includes an upper connecting pipe 11 and a lower connecting pipe 12 connected to the upper connecting pipe 11 via an intermediate pipe 15. The upper connecting pipe 11 has a vertical pipe connecting portion 13 connectable to a first vertical pipe P1, a horizontal pipe connecting portion 14 protruding from the side of the vertical pipe connecting portion 13 and connectable to a horizontal pipe P3, and a lower end portion 9 inserted into the through hole H.
The drainage manifold joint 10 of this embodiment is composed of an upper connecting pipe 11, a lower connecting pipe 12, and an intermediate pipe 15, which are resin joint components.

In the following explanation, the upper connecting pipe 11 side of the vertical pipe connecting portion 13 along the central axis O of the vertical pipe connecting portion 13 will be referred to as the upper side, and the lower connecting pipe 12 side will be referred to as the lower side.

The vertical pipe connection section 13 is equipped with a damming plate 13a on its inner surface. The damming plate 13a is installed at an angle of -30° to +30° from the vertical. If the installation angle is tilted beyond 20°, the swirling flow of wastewater swirled by the inclined plate may not be sufficiently blocked, resulting in a backflow into the horizontal pipe P3. Furthermore, if the installation angle is tilted beyond -30°, the received wastewater may rebound more, disrupting the flow of wastewater and causing significant pressure fluctuations within the pipe.

The horizontal pipe connecting portion 14 has a cylindrical shape and extends radially outward from the peripheral wall of the vertical pipe connecting portion 13 in a direction perpendicular to the central axis O. In the present embodiment, three horizontal pipe connecting portions 14 are arranged in the circumferential direction of the vertical pipe connecting portion 13.
Two of the three horizontal pipe connecting portions 14 are individually arranged at positions on either side of the central axis O in the radial direction. The remaining horizontal pipe connecting portions 14 extend in a radial direction perpendicular to the central axis O, in a direction that forms an angle of 90° in plan view with the directions in which the two horizontal pipe connecting portions 14 extend. Note that the number and extending directions of the horizontal pipe connecting portions 14 are not limited to this embodiment and can be changed as desired. As shown in FIG. 1 , a horizontal pipe (horizontal branch pipe) P3 is connected to the tip side of each horizontal pipe connecting portion 14.

The upper connecting pipe 11 is made of, for example, a polyvinyl chloride resin composition containing 0.1 to 1.0 parts by weight of non-expandable graphite per 100 parts by weight of polyvinyl chloride resin. The upper connecting pipe 11 is obtained, for example, by injecting the polyvinyl chloride resin composition into the cavity of a molding machine.

An intermediate pipe 15 is connected to the lower end 9 of the upper connecting pipe 11. The outer diameter of the intermediate pipe 15 is smaller than the outer diameter of the vertical pipe connecting portion 13 of the upper connecting pipe 11. The upper peripheral wall of the intermediate pipe 15 is fitted inside the lower end 9 of the vertical pipe connecting portion 13.

The intermediate tube 15 is made of a resin composition containing, for example, polyvinyl chloride resin and thermally expandable graphite, which is a thermally expandable fire-resistant material. That is, the intermediate tube 15 is produced by molding a resin composition containing the thermally expandable fire-resistant material. The intermediate tube 15 is produced, for example, by extrusion molding the resin composition.

The intermediate pipe 15 may have a single-layer structure in which the entire intermediate pipe 15 is made from a resin composition containing a heat-expandable fire-resistant material, or it may have a multi-layer structure consisting of multiple layers. In the case of a multi-layer structure, it is sufficient that any one of the layers is formed from a resin composition containing a heat-expandable fire-resistant material. For example, if the intermediate pipe 15 has a three-layer structure consisting of a surface layer, an intermediate layer, and an inner layer, the intermediate layer may be formed from a resin composition containing a heat-expandable fire-resistant material, and the surface layer, intermediate layer, and inner layer may contain a heat-absorbing agent in their resin compositions.

As an example, a single-layer structure can be used, consisting of a resin composition containing 1 to 20 parts by weight of thermally expandable graphite per 100 parts by weight of polyvinyl chloride resin. Alternatively, a three-layer structure can be used, consisting of a thermally expandable fire-resistant layer made of a resin composition containing 1 to 20 parts by weight of thermally expandable graphite per 100 parts by weight of polyvinyl chloride resin, and coating layers of a polyvinyl chloride resin composition that does not contain thermally expandable graphite that cover the inner and outer surfaces of the thermally expandable fire-resistant layer.

In other words, if the amount of thermally expandable graphite is less than 1 part by weight, sufficient thermal expansion may not be achieved during combustion, and the desired fire resistance may not be achieved. If the amount of thermally expandable graphite exceeds 20 parts by weight, the graphite may expand too much when heated, failing to maintain its shape and causing residue to fall out of the through holes H, resulting in reduced fire resistance.

When the intermediate tube 15 has a multi-layer structure, the resin composition containing the thermally expandable fire-resistant material is not particularly limited, but is preferably one containing 1 to 20 parts by weight of thermally expandable graphite per 100 parts by weight of polyvinyl chloride resin, more preferably 4 to 18 parts by weight, and even more preferably 6 to 16 parts by weight.
That is, if the amount of thermally expandable graphite is less than 1 part by weight, sufficient thermal expansion may not be obtained during combustion, and the desired fire resistance may not be obtained. If the amount of thermally expandable graphite is more than 20 parts by weight, excessive thermal expansion may occur due to heating, or the resin component may be insufficient, causing the residue to become brittle and unable to maintain its shape, causing the residue to fall off from the through holes H, and resulting in a decrease in fire resistance.
In the present invention, as will be described later, the height of the intermediate tube 15 (the length in the thickness direction of the slab) is set to be smaller than the thickness of a typical slab. Therefore, even if the content of thermally expandable graphite is relatively high, for example, 8 parts by weight or more, and the residue is brittle, the residue after thermal expansion can be retained within the slab and is less likely to fall off.
Furthermore, when the thermally expandable graphite content is relatively high, for example, 8 parts by weight or more, the compressive strength of the intermediate pipe 15 decreases, and the compression ratio measured based on the flattening test specified in JIS K 6741:2016 is 50% or less. Here, when the vertical pipe P1 or horizontal pipe P3 thermally expands or contracts, or when physical forces are applied during construction, stress concentrates at the contact points between the drainage manifold 10 and the upper and lower surfaces of the mortar M. Therefore, if stress is transmitted to the intermediate pipe 15, which has low compressive strength, it is prone to breakage. However, by setting the height of the intermediate pipe 15 to 150 mm or less, in other words, a height smaller than the thickness of a typical slab, stress is less likely to be transmitted to the intermediate pipe 15, making it less likely to break.

Examples of the polyvinyl chloride resin include polyvinyl chloride homopolymers; copolymers of vinyl chloride monomers and monomers having unsaturated bonds copolymerizable with the vinyl chloride monomers; and graft copolymers in which vinyl chloride is graft-copolymerized onto (co)polymers other than vinyl chloride. These may be used alone or in combination of two or more.
If necessary, the polyvinyl chloride resin may be chlorinated.

The intermediate layer containing thermally expandable graphite is black, so it is preferable that the surface layer and the inner layer contain a colorant other than black so that they can be distinguished from the intermediate layer.
The thickness of the surface layer and the inner layer is preferably 0.3 mm to 3.0 mm, and more preferably 0.6 mm to 1.5 mm. If the thickness of the coating layer is 0.3 mm or more, the mechanical strength of the pipe can be sufficiently ensured, and if it is 3.0 mm or less, a decrease in fire resistance can be suppressed.
Furthermore, it is preferable that the intermediate tube 15 satisfies the performance requirements set forth in JIS K6741.

The thermally expandable graphite used in this embodiment can be, for example, a crystalline compound obtained by acid treating powder of natural scaly graphite, pyrolytic graphite, kish graphite, or the like with an inorganic acid and a strong oxidizing agent to insert the inorganic acid between the layers of the graphite, followed by pH adjustment.
As the inorganic acid, concentrated sulfuric acid, nitric acid, selenic acid, etc. can be used. As the strong oxidizing agent, concentrated nitric acid, perchloric acid, perchlorates, permanganates, dichromates, hydrogen peroxide, etc. can be used.

By adjusting the pH, it is possible to use thermally expandable graphite, which is a crystalline compound that maintains the layered carbon structure, and whose pH is adjusted to 1.5 to 4.0, and whose 1.3-fold expansion temperature is 180°C to 270°C.

If the pH of the thermally expandable graphite is less than 1.5, the acidity is too strong and it is likely to cause corrosion of the molding device, and if the pH exceeds 4.0, the effect of promoting the carbonization of the polyvinyl chloride resin is weakened, and sufficient fire resistance may not be obtained.
The particle size of the thermally expandable graphite is not particularly limited, but may be, for example, in the range of 100 to 400 μm, preferably 120 to 350 μm.

Additives such as stabilizers, inorganic fillers, flame retardants, lubricants, processing aids, impact modifiers, heat resistance improvers, antioxidants, light stabilizers, UV absorbers, pigments, plasticizers, and thermoplastic elastomers may be added to the resin composition constituting the intermediate tube 15 as needed, provided that the purpose of this embodiment is not impaired.

The height of the intermediate pipe 15 is preferably 30 mm to 150 mm, more preferably 30 mm to 100 mm, and most preferably 30 mm to 80 mm. If the height of the intermediate pipe 15 is less than 30 mm, it is difficult to ensure sufficient joint strength when joining the upper connecting pipe 11 and the lower connecting pipe 12, and the volume required to block the pipe line when the pipe expands due to heating is insufficient. If the height of the intermediate pipe 15 exceeds 150 mm, the upper or lower end of the intermediate pipe 15 will protrude above or below the floor slab S when the floor slab S is thin, making it difficult to position the horizontal pipe P3 near the floor. If the lower end of the intermediate pipe 15 is located below the through hole H, the pipe will expand significantly below the through hole H during expansion, increasing the risk of the pipe falling out of the through hole H.
If the height of the intermediate pipe 15 is in the range of 30 mm to 150 mm, the typical floor slab thickness is 150 to 300 mm, and if applied to any floor slab thickness, the height will be such that the purpose of blocking the pipeline due to thermal expansion when heated by a fire, etc. Furthermore, if the height is in this range, the joint strength can be ensured for floor slabs of a typical thickness, and the height will be such that the intermediate pipe 15 can be accommodated in the through hole H.

The inner diameter of the intermediate pipe 15 is preferably larger than the inner diameter of the vertical pipe P1, more preferably 100 mm to 200 mm, even more preferably 110 mm to 175 mm, and most preferably 120 mm to 150 mm.
As described above, the height of the intermediate pipe 15 is 150 mm or less, and therefore the volume inside the intermediate pipe 15 is small. Therefore, if the inner diameter of the intermediate pipe 15 is smaller than the inner diameter of the vertical pipe P1, the intermediate pipe 15 is likely to be clogged by the wastewater flowing down from the vertical pipe P1, and excessive positive pressure is likely to occur.
On the other hand, if the inner diameter of the intermediate pipe 15 is larger than 200 mm, the inner diameter of the through hole H into which the drainage manifold 10 is inserted must be made larger, which makes it difficult to fill with the filler M and reduces workability.

The lower connecting pipe 12 is a pipe whose diameter is smaller below than above. The lower connecting pipe 12 is equipped with a connecting pipe section 16 located at its upper end and connected to the lower end of the intermediate pipe 15, a tapered pipe section 17 connected below the connecting pipe section 16, and a lower pipe section 18 connected to the lower end of the tapered pipe section 17 and to which the second vertical pipe P2 is connected. The connecting pipe section 16, tapered pipe section 17, and lower pipe section 18 are integrally formed, for example, by injection molding of a synthetic resin material.

The inner diameter of the connecting pipe portion 16 is larger than the outer diameter of the intermediate pipe 15. The lower portion of the peripheral wall of the intermediate pipe 15 is fitted inside the connecting pipe portion 16. The outer diameter of the upper end of the inclined pipe portion 17 is smaller than the outer diameter of the connecting pipe portion 16. Therefore, a peripheral step 16a is formed at the boundary between the lower end of the connecting pipe portion 16 and the upper end of the inclined pipe portion 17.
The outer diameter of the lower end of the inclined pipe portion 17 is smaller than the outer diameter of the upper end of the inclined pipe portion 17 .

The outer diameter of the lower pipe section 18 is smaller than the outer diameter of the connecting pipe section 16 and larger than the outer diameter of the lower end of the inclined pipe section 17. The size of the lower pipe section 18 in the direction of the central axis O is smaller than the size of the connecting pipe section 16 in the direction of the central axis O. The second vertical pipe P2 on the lower floor is fitted from below into the inside of the lower pipe section 18, thereby connecting the second vertical pipe P2 to the lower connecting pipe 12.

The upper connecting pipe 11 and the lower connecting pipe 12 may be made transparent. This allows the connection state of the upper connecting pipe 11 and the lower connecting pipe 12 to be visually confirmed from the outside. The upper connecting pipe 11 and the lower connecting pipe 12 may also be compounded with a flame retardant such as non-thermally expandable graphite, magnesium hydroxide, or aluminum hydroxide.

A vertical bush 21, a vertical packing 22, and a vertical ring 23 are provided at the upper end of the upper connecting pipe 11 to which the first vertical pipe P1 is connected.
The vertical bushing 21 includes a fitting portion 21 a, a swirl vane 21 b, and a swirl vane support leg 21 c. The fitting portion 21 a has a smaller diameter than the upper end of the vertical bushing 21 and is cylindrical so as to fit into the vertical pipe connecting portion 13 of the upper connecting pipe 11.

The swirl vanes 21b are supported by the swirl vane support legs 21c so that the projected area of the swirl vanes 21b as viewed in the pipe axis direction is 5% to 30% of the internal cross-sectional area of the first vertical pipe P1 and the inclination angle is 20° to 50°. The swirl vane support legs 21c extend substantially from the lower end of the fitting portion 21a with a width substantially the same as the horizontal width of the swirl vanes 21b, and the lower edge is inclined to follow the inclination of the swirl vanes 21b. The swirl vane support surface of the swirl vane support leg 21c is formed in an arc-shaped cross section and supports the swirl vanes 21b slightly above the lower edge.
The swirl vane 21b is applied when high drainage performance is required depending on the size of the building and the number of drainage fixtures, so it may be omitted in buildings where high drainage performance is not required.

The vertical packing 22 is made of a rubber material typically used in drainage equipment, such as ethylene-propylene-diene rubber (EPDM). The vertical packing 22 has a lip portion 22a at its upper end that is in watertight contact with the outer circumferential surface of the first vertical pipe P1, and is fitted into the vertical bushing 21 so that its upper end surface is substantially flush with the upper end surface of the vertical bushing 21.
As shown in FIG. 2, the lip portion 22a is configured so that its diameter gradually decreases toward its lower end when the first vertical pipe P1 is not inserted. The upper end of the lip portion 22a has a diameter that is approximately the same as or slightly larger than the outer diameter of the first vertical pipe P1, and the lower end has a diameter that is smaller than the outer diameter of the first vertical pipe P1. A step 22b that protrudes radially inward is formed at the lower end of the lip portion 22a. The end of the first vertical pipe P1 abuts against this step 22b, absorbing thermal expansion and contraction of the first vertical pipe P1.

The vertical ring 23 is fitted onto the upper end of the vertical bush 21 and prevents the vertical packing 22 from coming off the vertical bush 21 by a flange portion 23 a provided at one end.
The vertical bushing 21 to the vertical ring 23 can be assembled and integrated in advance, and then the fitting portion 21a of the vertical bushing 21 can be fitted into the vertical pipe connecting portion 13 of the upper connecting pipe 11 and bonded.

A horizontal bushing 31, a horizontal packing 32, and a horizontal ring 33 are provided at the tip of the horizontal pipe connecting portion 14 that connects the horizontal pipe P3.
One end of the horizontal bushing 31 is fitted and bonded to the horizontal pipe connecting portion 14 of the upper connecting pipe 11, and the other end is expanded in diameter.

The horizontal packing 32 is made of a rubber material typically used in drainage equipment, such as ethylene-propylene-diene rubber (EPDM). The horizontal packing 32 is fitted into the enlarged other end of the horizontal bushing 31 and adheres watertight to the outer surface of the horizontal pipe P3.

The horizontal ring 33 is fitted onto the enlarged diameter portion of the horizontal bush 31 , and a flange portion 33 a provided at one end prevents the horizontal packing 32 from coming off the vertical ring 23 .
The vertical bushing 21, the vertical ring 23, the horizontal bushing 31, and the horizontal ring 33 are all obtained by injection molding a polyvinyl chloride resin composition containing 0.1 to 1.0 parts by weight of non-expandable graphite per 100 parts by weight of polyvinyl chloride resin.

"Installation of drainage manifold joint"
The drainage manifold 10 as described above is used at the junction of horizontal branch pipes on each floor of the drainage riser of a multi-story building, as shown in FIG. 1, and is installed as follows.
That is, the portions including the fitting connections of the lower connecting pipe 12, intermediate pipe 15, and upper connecting pipe 11 are installed facing the through-hole H in the floor slab S, and a second vertical pipe P2 on the lower floor (for example, a commercially available Eslon (registered trademark) fire-resistant VP pipe manufactured by Sekisui Chemical Co., Ltd.) is fitted and glued to the lower pipe portion 18 of the lower connecting pipe 12. During this installation, the upper end of the lower connecting pipe 12 and the lower ends of the intermediate pipe 15 and upper connecting pipe 11 are housed inside the through-hole H.
In addition, the lower end of the first vertical pipe P1 on the upper floor is fitted into the vertical packing 22 via the vertical ring 23.

Next, the through holes H in the floor slab S are filled with a filler material (sound-proofing material) M such as mortar or rock wool, and the upper end of the lower connecting pipe 12 and the lower end of the intermediate pipe 15 and upper connecting pipe 11 are embedded in the filler material M. The upper end of the inclined pipe section 17 and the connecting pipe section 16 of the lower connecting pipe 12 are embedded in the filler material M. The portion of the upper connecting pipe 11 below the lower end of the horizontal pipe connecting section 14 (lower end 9) is embedded in the filler material M. It is preferable to use mortar as the filler material M, as it has excellent residue retention properties.
Then, the end of the horizontal pipe P3 is inserted into the horizontal bush 31 via the horizontal ring 33 and the horizontal packing 32 to connect the horizontal pipe P3.

The drainage manifold 10 of this embodiment has the installation structure described above, in which the intermediate pipe 15 is buried inside the through-hole H of the floor slab S while being surrounded by filler material M. In addition, the lower end 9 of the upper connecting pipe 11, the upper end of the inclined pipe section 17, and the connecting pipe section 16, which are located outside the intermediate pipe 15, are also buried inside the through-hole H of the floor slab S while being surrounded by filler material M.
With this structure, if a fire breaks out on the floor below and the through-hole H and its surrounding area are heated by the flames, the thermally expandable graphite contained in the intermediate pipe 15 will expand. The expanded intermediate pipe 15 will then block the lower end of the upper connecting pipe 11 or the upper end of the lower connecting pipe 12. This will prevent flames and smoke from flowing from the floor below to the floor above, thereby preventing the spread of fire.

In addition, it is assumed that the lower connecting pipe 12 will melt down due to the heat during a fire. Even if the lower connecting pipe 12 does melt down, the intermediate pipe 15 will expand and close the through-hole H, thereby preventing the spread of fire. This ensures that the through-hole H can be reliably closed in the event of a fire, thereby preventing the spread of fire.

With a structure equipped with the drainage manifold joint 10 shown in Figure 1, an intermediate pipe 15 with a height of 30 mm or more and 150 mm or less can be reliably placed within the through-hole H, regardless of the floor slab S thickness, which may be between 150 and 300 mm. Therefore, the structure shown in Figure 1 can be applied to floor slabs S of any thickness. Therefore, the structure of this embodiment is highly versatile and can be widely applied to any building with a typical slab thickness.

In the structure shown in FIG. 1, a tapered inclined pipe section 17 is provided below the connecting pipe section 16, and this inclined pipe section 17 is securely held by the filler material M, thereby reliably preventing the connecting pipe section 16 from falling even when heated by a flame or the like.
1, the connecting pipe portion 16 has a peripheral step 16a at its lower end, so that when the intermediate pipe 15 expands in the event of a fire, the peripheral step 16a is securely caught by the filler material M. This prevents the lower connecting pipe 12 from burning down and falling, and the expansion of the intermediate pipe 15 reliably closes the through hole H, ensuring fire resistance.

Second Embodiment
FIG. 4 is a cross-sectional view showing an example of a joint structure in which a drainage manifold according to a second embodiment of the present invention is applied to a fire-resistant structure.
In this embodiment, an intermediate pipe 50 is provided that has a different structure from the intermediate pipe 15 used in the first embodiment. The intermediate pipe 50 of this embodiment is equivalent to the intermediate pipe 15 in terms of inner and outer diameter, height, thickness, shape, etc., but is made of a resin that does not contain thermally expandable graphite, such as a polyvinyl chloride resin. Alternatively, the intermediate pipe 50 is made of a polyvinyl chloride resin composition that contains 0.1 to 1.0 parts by weight of non-expandable graphite per 100 parts by weight of polyvinyl chloride resin.

This embodiment is characterized by the provision of a fire-resistant layer 51 made of a heat-expandable fire-resistant material such as heat-expandable graphite around the outer periphery of the lower end 9 of the upper connecting pipe 11 located outside the intermediate pipe 50 and the outer periphery of the connecting pipe portion 16 located outside the intermediate pipe 50. The fire-resistant layer 51 can be constructed by wrapping a heat-expandable fire-resistant sheet or tape containing heat-expandable graphite around it.

The fire-resistant layer 51 is made of the same material as that of the intermediate pipe 15 of the first embodiment.
That is, the entire structure may be a single layer made of a resin composition containing a heat-expandable fire-resistant material, or a multi-layer structure made of multiple layers including a sound-insulating layer, a sound-absorbing layer, etc. In the case of a multi-layer structure, it is sufficient that any one of the layers is formed from a resin composition containing a heat-expandable fire-resistant material. For example, a portion of the sound-insulating layer or sound-absorbing layer covering the outer periphery of the upper connecting pipe 11 or the lower connecting pipe 12 may be formed from a resin composition containing a heat-expandable fire-resistant material and function as a fire-resistant layer. Alternatively, the fire-resistant layer may be a multi-layer structure formed by wrapping a single-layer fire-resistant sheet made of a resin composition containing a heat-expandable fire-resistant material. Among these, a structure wrapped with a fire-resistant sheet is preferable because it is easy to implement at the construction site.
In addition, if the intermediate pipe 50 does not contain thermally expandable graphite, a sheet-shaped fire-resistant material containing thermally expandable graphite may be wrapped around the outer surface of the intermediate pipe 50 or the outer surface of the sound-insulating material covering the intermediate pipe 50, and the fire-resistant material may be embedded in the slab penetration portion.

The fire-resistant layer 51 of this embodiment is formed to have the same height as the intermediate pipe 15 of the previous example. That is, the fire-resistant layer 51 is formed to have a height of 30 mm or more and 150 mm or less.
The other structures are the same as those of the first embodiment, and therefore a description of the other structures will be omitted.

When the structure of the second embodiment is applied to the floor slab S having the structure shown in Fig. 1, a fire-resistant layer 51 is embedded inside the through-hole H. Even when heated during a fire, the intermediate pipe 50 does not expand, but the thermally expandable graphite contained in the fire-resistant layer 51 does expand.
When a fire occurs, the fire-resistant layer 51 is heated and expands to crush the lower end 9 of the upper connecting pipe 11, the connecting pipe portion 16, and the intermediate pipe 15, which have been softened by the heat, thereby blocking the through-hole H. As a result, flames and smoke from a fire that has broken out on a lower floor are not transmitted to an upper floor through the through-hole H, thereby achieving fire resistance.

Modifications of this embodiment include, for example, a first modification shown in Fig. 5 and a second modification shown in Fig. 6. In both of these modifications, the intermediate pipe 50 is not provided, and the upper connecting pipe 11 and the lower connecting pipe 12 are directly connected (without the intermediate pipe 50).
5, the lower end 9 of the upper connecting pipe 11 is a spigot, and the upper end (connecting pipe portion 16) of the lower connecting pipe 12 is a socket. The lower end 9 of the upper connecting pipe 11 is fitted into the upper end of the lower connecting pipe 12.
6, the lower end 9 of the upper connecting pipe 11 is a socket, and the upper end (connecting pipe portion 16) of the lower connecting pipe 12 is a spigot. The upper end of the lower connecting pipe 12 is fitted into the lower end 9 of the upper connecting pipe 11.
In both of these modified examples, a fire-resistant layer 51 containing a heat-expandable fire-resistant material is provided around (on the outer periphery of) the connecting portion where the upper connecting pipe 11 and the lower connecting pipe 12 are connected. The connecting portion can also be considered as the fitting portion where the upper connecting pipe 11 and the lower connecting pipe 12 are fitted together. The fire-resistant layer 51 can have a configuration similar to that of the second embodiment. For example, the height of the fire-resistant layer 51 is 150 mm or less.
Furthermore, like the inner diameter of the intermediate pipe 15, the inner diameter of the lower end 9 of the upper connecting pipe 11 in FIG. 5 and the upper end (connecting pipe portion 16) of the lower connecting pipe 12 in FIG. 6 is preferably larger than the inner diameter of the vertical pipe P1, more preferably 100 mm or more and 200 mm or less, even more preferably 110 mm or more and 175 mm or less, and most preferably 120 mm or more and 150 mm or less.
Furthermore, a fireproof layer 51 is provided on the outer periphery of the lower end 9 of the upper connecting pipe 11 in Fig. 5 and the connecting pipe portion 16 of the lower connecting pipe 12 in Fig. 6. Therefore, by making the height of the lower end 9 or the connecting pipe portion 16 equal to or less than the slab thickness, the fireproof layer 51 can be reliably provided in the through hole H. For example, the height of the lower end 9 or the connecting pipe portion 16 is 300 mm or less, and preferably 150 mm or less.
In both of these modified examples, the intermediate tube 50 is not required, and the number of parts can be reduced.

In any of the second embodiment shown in FIG. 4, the first modified example shown in FIG. 5, and the second modified example shown in FIG. 6, it is preferable that the fire-resistant layer 51 be provided around (on the outer periphery of) the portion shown in (1) or (2) below.
(1) The portion where the upper connecting pipe 11, the lower connecting pipe 12, and the intermediate pipe 50 are not connected to each other, in other words, the portion formed by one pipe material. (2) The portion where two pipe materials overlap, such as the connection portion between the upper connecting pipe 11 and the intermediate pipe 50, the connection portion between the intermediate pipe 50 and the lower connecting pipe 12, and the connection portion between the upper connecting pipe 11 and the lower connecting pipe 12.

For example, when three pipes, the upper connecting pipe 11, the intermediate pipe 50, and the lower connecting pipe 12, overlap, it is not desirable to provide the fire-resistant layer 51 around (the outer periphery of) the overlapping portion of three or more pipes. This is because the more pipes overlap, the greater the rigidity of the pipe connection, making the connection less likely to deform. This makes the connection less likely to deform when the fire-resistant layer 51 expands, and as a result, less likely to clog. Therefore, providing the fire-resistant layer 51 around the portion shown in (1) above rather than around the portion shown in (2) above in Figures 5 and 6 makes it easier for the expansion of the fire-resistant layer 51 to clog the drainage manifold 10. Note that, as long as the height of the fire-resistant layer 51 is 150 mm or less, it may be provided around both the portion shown in (1) above and the portion shown in (2).

From a similar perspective, even in cases where (1) or (2) above applies, it is preferable that no protrusions (ribs), such as damming plates 13a or swirl vanes 21b, are provided on the inner surface of the portion where the fire-resistant layer 51 is wrapped. In other words, if such protrusions are provided, the rigidity of the pipe material increases and the pipe material becomes less likely to deform, making the pipe material less likely to become blocked when the fire-resistant layer 51 expands.

In the structures of the first and second embodiments and their modifications, sound-insulating covers may be provided on the outer periphery of the upper connecting pipe 11 and the outer periphery of the lower connecting pipe 12 as a measure to prevent noise such as drainage noise. The sound-insulating cover may be wrapped around the lower connecting pipe 12 before delivery to the site (at the time of shipment from the factory), or the sound-insulating cover may be wrapped around the pipe after installation on site.
The soundproof cover can be a sheet made of soft vinyl chloride, butyl rubber, or PP (polypropylene) with a thickness of about 0.8 to 2 mm. Alternatively, a laminated soundproof cover can be used, in which polyester fiber, urethane foam, or glass wool with a thickness of about 5 to 20 mm is laminated on the inside of such a sheet.

The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.
In addition, within the scope of the spirit of the present invention, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described modifications may be combined as appropriate.

1...Fire-resistant structure of drainage manifold joint,
10...Drainage collection joint,
11...upper connecting pipe,
12...Lower connecting pipe,
13...Vertical pipe connection part,
15...Intermediate tube,
16...connecting pipe part,
17... Inclined pipe section,
21b...swirl vane,
50...Intermediate tube,
51... Fireproof layer,
H...through hole,
M: Soundproofing material (mortar),
S...Floor slab.

Claims (6)

A joint comprising: an upper connecting pipe made of resin, the upper connecting pipe having a horizontal pipe connecting portion on the side thereof and a swirl vane and a dam plate on the inner surface thereof; and a lower connecting pipe made of resin connected to the upper connecting pipe,
a lower end of the upper connecting pipe and an upper end of the lower connecting pipe are disposed in the through-hole of the floor slab;
A connecting pipe section is formed to connect the lower end of the upper connecting pipe to the upper end of the lower connecting pipe, and a tapered pipe section is formed below the connecting pipe section,
The lower end of the upper connecting pipe, the connecting pipe section, and the upper part of the inclined pipe section are disposed in the through hole of the floor slab,
a fire-resistant layer containing a heat-expandable fire-resistant material is provided on the outer periphery between the lower end of the horizontal pipe connecting portion and the upper end of the inclined pipe portion, below the lower end of the swirl vane and the lower end of the damming plate (excluding, however, a case in which the fire-resistant layer is provided on the outer periphery of the portion where the upper connecting pipe and the lower connecting pipe are connected and overlap each other);
A drainage manifold joint in which the height of the fire-resistant layer is 30 mm or more and 150 mm or less. A joint comprising: an upper connecting pipe made of resin, the upper connecting pipe having a horizontal pipe connecting portion on the side thereof and a swirl vane and a dam plate on the inner surface thereof; and a lower connecting pipe made of resin connected to the upper connecting pipe,
a lower end of the upper connecting pipe and an upper end of the lower connecting pipe are disposed in the through-hole of the floor slab;
A connecting pipe section is formed to connect the lower end of the upper connecting pipe to the upper end of the lower connecting pipe, and a tapered pipe section is formed below the connecting pipe section,
The lower end of the upper connecting pipe, the connecting pipe section, and the upper part of the inclined pipe section are disposed in the through hole of the floor slab,
a fire-resistant layer including a heat-expandable fire-resistant material is provided on an outer periphery between the lower end of the horizontal pipe connection portion and the upper end of the inclined pipe portion;
The fire-resistant layer is provided on the outer periphery between the lower end of the horizontal pipe connecting portion and the lower end of the upper connecting pipe (excluding a case where a protrusion including the swirl vane and the dam plate is provided on the inner surface between the lower end of the horizontal pipe connecting portion and the lower end of the upper connecting pipe),
The height of the fireproof layer is 30 mm or more and 150 mm or less.
Drainage collection joint. A joint comprising: an upper connecting pipe made of resin having a horizontal pipe connection portion on the side and swirl vanes on the inner surface ; a lower connecting pipe made of resin connected to the upper connecting pipe; and an intermediate pipe provided between the upper connecting pipe and the lower connecting pipe and below the lower end of the swirl vanes ,
a lower end of the upper connecting pipe and an upper end of the intermediate pipe disposed in a through hole of the floor slab;
A connecting pipe section is formed to connect the lower end of the intermediate pipe to the upper end of the lower connecting pipe, and a tapered pipe section is formed below the connecting pipe section,
a lower end of the upper connecting pipe and an upper portion of the intermediate pipe are disposed in the through hole of the floor slab;
a fire-resistant layer including a heat-expandable fire-resistant material is provided on an outer periphery of the intermediate pipe at a portion where the upper connecting pipe, the lower connecting pipe, and the intermediate pipe are not connected to each other;
The height of the fire-resistant layer is 30 mm or more and 150 mm or less,
The connecting pipe portion is a spigot or a socket.
Drainage collection joint. A drainage manifold fitting as described in any one of claims 1 to 3, wherein the lower connecting pipe has a sound-insulating cover wrapped around its outer periphery. The drainage manifold joint described in claim 4, wherein the sound-insulating cover is a sheet of butyl rubber. A drainage manifold joint as described in any one of claims 1 to 5, wherein the fire-resistant layer has a multi-layer structure consisting of multiple layers including a sound-insulating layer and a sound-absorbing layer.