JP6912202B2 - duct - Google Patents

Description

The present invention relates to a duct for ventilation, air conditioning, etc. in a building such as a house, and particularly to a duct in which a heat insulating layer is provided on the outer periphery of a metal duct body.

A duct in a building such as a house has, for example, a duct main body made of a spiral steel pipe and a heat insulating layer made of rock wool provided on the outer periphery thereof. At the time of construction, first, the duct body is suspended and supported by a hanging tool in the ceiling or the like. After that, the outer circumference of the duct body is covered with a heat insulating layer.

In the duct of Patent Document 1, the heat insulating layer is composed of a plurality of layers of non-combustible heat insulating material. This heat insulating layer is shipped from the factory in a state of being spirally wound around the outer circumference of a duct body made of a spiral steel pipe. Therefore, it is not necessary to cover the duct body with the heat insulating layer at the duct construction site.

Japanese Patent No. 35033333

This type of duct is required to have fire resistance. For example, in the case of a general heat insulating layer made of rock wool, the thickness needs to be about 50 mm or more in order to satisfy the fire resistance. For this reason, the thickness of the entire duct increases, and it may be necessary to lower the ceiling in order to secure a space for installing the duct behind the ceiling, for example.
Further, when the duct is suspended and supported with the heat insulating layer covered in advance on the outer periphery of the duct body, the hanging tool is hung around the outer periphery of the heat insulating layer. For this reason, in a general heat insulating layer made of rock wool, the cross section is deformed so as to be locally crushed by tightening the hanging tool or the weight of the duct. At such a cross-sectional deformation portion, the volume of the internal air layer of the heat insulating layer is reduced, so that the heat insulating property may be impaired.

According to the duct of Patent Document 1, the structure is such that the heat insulating layer is spirally provided on the outer periphery of the duct body made of a spiral metal pipe and is carried to the construction site and installed, but the density of the heat insulating layer is high. There is no description as to how much fire resistance and cross-sectional retention can be ensured.
In view of the above circumstances, the present invention is a duct in which a heat insulating layer is spirally provided on the outer periphery of a duct body made of a spiral metal pipe, which satisfies fire resistance while suppressing the thickness of the heat insulating layer and is supported by being suspended by a hanging tool or the like. Even so, the purpose is to prevent cross-sectional deformation.

In order to solve the above problems, the present invention uses a duct body made of a metal spiral tube and a duct body.
A heat insulating layer made of a non-combustible heat insulating material spirally coated on the outer circumference of the duct body,
A surface layer made of a non-combustible sheet that covers the outer periphery of the heat insulating layer is provided.
Density of the heat insulating ^layer, characterized in that it is a ^{150kg / m 3 ~200kg / m 3} .
Preferably, the density of the heat insulating layer is about ^{180 kg / m 3.}
Here, the density of the heat insulating layer means the weight per unit volume of the heat insulating layer including the internal air layer.

As a result, sufficient fire resistance can be obtained even if the thickness of the heat insulating layer is small. For example, fire resistance performance equal to or higher than that when ^{general rock wool (density 40 kg / m 3} or more) having a thickness of 50 mm is used as the heat insulating layer can be obtained. In addition, a certain degree of hardness can be imparted to the heat insulating layer, and even if the hanging tool is hung on the outside of the heat insulating layer or the weight of the duct is applied to the contact portion with the hanging tool or the like, the heat insulating layer is local. Can be prevented from being crushed. As a result, it is possible to prevent the heat insulating property from being impaired.

The thickness of the heat insulating layer is preferably 15 mm to 25 mm. Preferably, the thickness of the heat insulating layer is about 20 mm. As a result, the thickness of the heat insulating layer can be reduced while ensuring the fire resistance and heat insulating properties of the duct, and the outer diameter of the duct can be reduced. Therefore, it is possible to provide a margin in the piping space of the duct.

It is preferable that the non-combustible heat insulating material is made of glass fiber felt.
As a result, fire resistance and heat insulating properties can be reliably ensured while suppressing the thickness of the heat insulating layer, and cross-sectional deformation of the duct can be reliably prevented. By applying needle punching to the glass fibers, the glass fibers can be in an entangled state so as not to loosen each other. Furthermore, the heat insulating layer can have a desired density by adjusting the amount of glass fibers and the like.

According to the duct according to the present invention, it is possible to satisfy the fire resistance while suppressing the thickness of the heat insulating layer, and it is possible to prevent the cross-sectional deformation even if it is hung with a hanging tool or the like.

FIG. 1 is a perspective view showing a duct according to an embodiment of the present invention with a hanging tool attached. FIG. 2 is a side view showing the duct with more omissions as the components on the outer peripheral side are omitted. FIG. 3 is a cross-sectional view of the duct along lines III-III of FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
1 and 2 show a duct 1 in a building such as a house. Although detailed illustration is omitted, the duct 1 is for exhausting around the range hood of the kitchen, for example, and extends from the range hood to the ventilation port of the outer wall along the ceiling. As shown in FIG. 1, the duct 1 is suspended and supported by the hanging tool 2.

As shown in FIG. 3, the duct 1 includes a duct main body 10, a heat insulating layer 20, and a surface layer 30. As shown in FIG. 2, the duct main body 10 is composed of a metal spiral pipe. Specifically, the duct body 10 is made of a strip-shaped steel plate such as a strip-shaped galvanized steel plate, stainless steel, or galvalume steel plate. The duct main body 10 is formed by winding a strip-shaped steel plate in a spiral shape and crimping adjacent edges that are one circumference apart in a goby shape.

The thickness of the duct body 10 is, for example, about 0.3 mm to 2 mm, the inner diameter is about 50 mm to 1000 mm, and the pitch width is about 80 to 140 mm, but the present invention is not limited thereto.

As shown in FIG. 3, the heat insulating layer 20 is coated on the outer periphery of the duct main body 10. The heat insulating layer 20 has a plurality of layers (here, four layers) of non-combustible heat insulating material 21. Each non-combustible heat insulating material 21 is composed of a strip-shaped glass fiber felt. Fiberglass felt consists of a large number of short fiberglass fibers. The average length of the glass fiber is, for example, about 2 inch to 3 inch. These glass fibers are intertwined so as not to loosen each other.

In the production of glass fiber felt, a large number of the glass fibers are deposited in the form of cotton, and the deposit is needle punched. As a result, the glass fibers can be entwined with each other, and further compacted to increase the density. In other words, by adjusting the amount of glass fibers and the like, the glass fiber felt and thus the heat insulating layer 20 can have a desired density.

Density Density of the glass fiber felt, thus the heat insulating layer 20 ^is 150kg / ^{m 3} ~200kg / m 3 approximately, preferably from 180 kg / ^{m 3} approximately. If the density is ^{lower than about 150 kg / m 3,} it may be cut by the tension in the manufacturing process. If the density is ^{higher than about 200 kg / m 3} , the weight increases and the cost increases.
The thickness of each non-combustible heat insulating material 21 is, for example, about 3 mm to 8 mm, preferably about 5 mm. The pitch width of each non-combustible heat insulating material 21 is preferably equal to the pitch width of the duct body 10.

As shown in FIG. 3, a plurality of (four) non-combustible heat insulating materials 21 are sequentially laminated on the outer periphery of the duct main body 10. The thickness of the heat insulating layer 20 is 15 mm to 25 mm, preferably about 20 mm.

As shown in FIG. 2, each non-combustible heat insulating material 21 is wound in a spiral shape. The edges of each non-combustible heat insulating material 21 adjacent to each other are abutted so as not to overlap each other and to prevent a gap from being opened. As a result, the spiral linear seam 21d is formed. The spiral linear seams 21d and 21d of the non-combustible heat insulating materials 21 and 21 adjacent to each other on the inner peripheral side and the outer peripheral side are preferably displaced from each other.

The non-combustible heat insulating materials 21 and 21 that overlap each other on the inner peripheral side and the outer peripheral side are adhered to each other by an adhesive (not shown). Although the adhesive is applied to the entire inner surface of the non-combustible heat insulating material 21 on the outer peripheral side, it may be applied only to both ends in the width direction of the non-combustible heat insulating material 21. The adhesive is preferably a nonflammable adhesive, and examples thereof include an inorganic silicate matrix and an ethylene-vinyl acetate adhesive.

As shown in FIG. 3, a resin film 25 is coated on the inner side surface of the innermost non-combustible heat insulating material 21. As a result, the resin film 25 is interposed between the heat insulating layer 20 and the duct body 10. The material of the resin film 25 is, for example, polyethylene terephthalate (PET), but the material is not limited thereto. The thickness of the resin film 25 is extremely thin, for example, several μm to several hundred μm. In FIG. 3, the thickness of the resin film 25 is exaggerated. In FIGS. 1 and 2, the resin film 25 is not shown.
The non-combustible heat insulating material 21 and the resin film 25 are adhered with the same non-combustible adhesive (not shown) as described above. On the other hand, the resin film 25 and the duct main body 10 are not adhered to each other, so that the duct main body 10 and the heat insulating layer 20 can be easily separated.
The resin film 25 and the duct body 10 may be adhered to each other.

As shown in FIG. 1, the outer peripheral surface of the heat insulating layer 20 (the outermost surface of the outermost noncombustible heat insulating material 21) is covered with the surface layer 30. The surface layer 30 is made of a strip-shaped non-combustible sheet such as an aluminum glass cloth, and is spirally wound around the outer periphery of the heat insulating layer 20. As shown in FIG. 2, the edges of the surface layer 30 adjacent to each other are overlapped by, for example, about 10 mm. The surface layer 30 and the heat insulating layer 20 are adhered with the same nonflammable adhesive (not shown) as described above.
The material of the surface layer 30 is not limited to aluminum glass cloth, and may be aluminum foil non-combustible paper, aluminum foil polyethylene resin split fiber, or the like.

The duct 1 of the present invention is shipped from the factory in a completed state, that is, in a state where the heat insulating layer 20 is provided on the outer periphery of the duct main body 10 and the surface layer 30 is further provided on the outer periphery thereof, and is carried to the construction site of the building to the ceiling. It is installed on the back.
Since the thickness of the heat insulating layer 20 is about 15 mm to 25 mm, the outer diameter of the duct 1 can be made sufficiently smaller than that using, for example, 50 mm thick rock wool. Therefore, the duct 1 can be piped in a narrow space such as the ceiling of a building with a margin. There is no need to lower the ceiling to secure piping space.
A certain degree of hardness can be imparted to the heat insulating layer 20. Therefore, even if the hanging tool 2 is hung around the outer circumference and tightened, or the weight of the duct 1 is applied to the hanging tool 2, the heat insulating layer 20 can be prevented from being locally crushed, and the cross-sectional deformation of the duct 1 is deformed. Can be prevented. Therefore, sufficient heat insulating properties can be ensured even at the contact portion with the hanging tool 2.

Moreover, according to the duct 1 of the present invention, sufficient fire resistance can be ensured. For example, it is possible to obtain a fire resistance performance equal to or higher than that of rock wool having a thickness of 50 mm. That is, when the duct 1 is exposed to an open flame from the inside to set the temperature of the inner surface of the duct 1 to about 600 ° C., the temperature of the outside of the duct body 10 can be maintained within 150 ° C.

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.
For example, the number of layers of the non-combustible heat insulating material 21 constituting the heat insulating layer 20 is not limited to four, but may be five or more, two to three, or a single layer.
The duct 1 of the present invention is not limited to the exhaust around the range hood, and can be applied as various ducts for ventilation of a living room and the like.

An embodiment will be described. However, the present invention is not limited to the following examples.
A duct 1 substantially similar to that in FIGS. 1 and 2 was produced.
The duct main body 10 was a spiral tube made of galvanized steel sheet, and the thickness thereof was 0.5 mm, the inner diameter was 150 mm, and the pitch width was 150 mm.
The heat insulating layer 20 is composed of four layers of non-combustible heat insulating material 21.
Glass fiber felt was used as the non-combustible heat insulating material 21.
The average length of the glass fibers constituting the glass fiber felt was 2 to 3 inches.
The number of needle punches was 360 times.
The thickness of each non-combustible heat insulating material 21 was 5 mm.
The thickness of the heat insulating layer 20 was 20 mm.
The surface layer 30 was an aluminum glass cloth.

Applying a direct flame from the inner portion to the duct 1, to measure the inner temperature of the external surface temperature and the duct body 10 of the duct 1.
The inner surface temperature of the duct 1 was 600 ° C.
The temperature outside the duct body 10 was 150 ° C.
Therefore, it was confirmed that sufficient fire resistance can be obtained.

The present invention is applicable to air conditioning equipment for buildings such as houses.

1 Duct 2 Suspension tool 10 Duct body 20 Insulation layer 21 Non-combustible insulation 21d Spiral linear seam 25 Resin film 30 Surface layer

Claims (2)

It is a ventilation duct that extends from the range hood of the kitchen of the building to the ventilation port of the outer wall behind the ceiling.
The duct body made of metal spiral pipe and
A heat insulating layer made of a plurality of strip-shaped non-combustible heat insulating materials spirally coated on the outer circumference of the duct body, and
A surface layer made of a non-combustible sheet that covers the outer periphery of the heat insulating layer is provided.
Density of the thermal insulating layer is a ^{150kg / m 3 ~200kg / m 3} , the plurality of noncombustible insulation material are sequentially stacked on an outer periphery of the duct body, and inner and incombustible insulation material to each other overlap on the outer peripheral side It is adhered by a non-combustible adhesive applied to the entire area between these non-combustible insulation materials .
The thickness of the heat insulating layer is 15 mm to 25 mm.
A duct characterized in that the non-combustible heat insulating material is made of glass fiber felt. The duct according to claim 1, which is suspended and supported by a hanging tool behind the ceiling.
A duct characterized in that the nonflammable adhesive is an inorganic silicate matrix.

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