JPH06221662A - Air duct - Google Patents

Abstract

PURPOSE:To simplify a duct forming construction and to prevent vapor condensation by winding a nonflammable or flame retardant sheet on an outer periphery of an air duct body, and forming a layer impregnated with inorganic formable silicate on the sheet. CONSTITUTION:An air duct 1 is wound with a nonflammable or flame retardant sheet 3 impregnated with inorganic foamable silicate on an air duct body 2 such as a spiral steel tube, etc. Since the silicate has excellent heat insulation as a heat insulator and moisture absorption/radiation properties, it is effective to prevent vapor condensation. Adherence of the silicate to the sheet 3 is excellent, and the sheet 3 can be wound in close contact on the body 2. Further, the duct 2 obtained by winding the sheet 3 previously impregnated with the silicate in a manufacturing factory on the body 2 can be supplied to a construction site to simplify a duct construction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air duct used for forming a duct provided on a wall of a building, capable of preventing dew condensation and simplifying the duct forming work.

[0002]

2. Description of the Related Art In a concrete structure,
A duct is provided on the wall of a building to allow air to flow between the inside and outside of the building.When forming this duct, a cylinder such as polyvinyl chloride is used when pouring concrete into the wall of the building. The method of embedding so as to penetrate the body is adopted.

However, in cold regions, the air in a warm room comes into contact with a duct cooled by cold outside air in the cold region, so that condensed water is generated in the duct, and this condensed water wets the structure. ing.

For this reason, a duct supplier forms a through hole in a concrete mold which is slightly larger than the polyvinyl chloride pipe forming the duct at the time of pouring concrete, and then a heat insulation worker uses the polyvinyl chloride pipe as the through hole. It is set and filled around the tube with a heat insulating material such as glass fiber mat or rock wool.

[0005]

However, when a through hole for forming a duct is opened and a heat insulating material is filled around the duct pipe at the time of such concrete placing, many steps are required, and the heat insulating material is used. Not only is it laborious to carry out the work, such as having to separately transport it to each floor by a lift, etc., but there is also the problem that the glass fiber causes a rash on the worker.

Further, when filling the heat insulating material around the duct pipe, if there is a gap between the duct pipe and the heat insulating material, dew condensation water is easily generated, so that no gap can be formed between the duct pipe and the heat insulating material. However, due to the recent shortage of craftsmen and deterioration in quality, such close-fitting has become difficult.

The present invention has been made in view of the above circumstances, and in view of the shortage of manpower and the safety of construction work in recent years, the duct work can be simplified, and the duct pipe and the heat insulating material can be surely brought into close contact with each other, so that the heat insulating property can be improved. It is an object of the present invention to provide an air duct that has good properties and can effectively prevent dew condensation.

[0008]

In order to achieve the above object, the present invention wraps a non-combustible or flame-retardant sheet around the outer peripheral surface of an air duct body, and an impregnated layer of an inorganic silicate foam on the sheet. An air duct characterized by being formed.

Here, as the above-mentioned sheet, a mixed paper of phosphorylated pulp and glass fiber, an aluminum hydroxide mixed paper,
Glass fiber mixed paper, rock wool, glass fiber, carbon fiber alone or mixed woven fabric or non-woven fabric is preferably used.

[0010]

In the air duct of the present invention, a non-combustible or flame-retardant sheet in which an inorganic silicate foam is impregnated is wound around an air duct body such as a spiral steel pipe, and the inorganic silicate foam is used as a heat insulating material. Since it has good heat insulating properties and the inorganic silicate foam absorbs and releases moisture, it is effective in preventing dew condensation. In addition, the adhesiveness of the inorganic silicate foam to the above-mentioned sheet is good, the above-mentioned sheet can be closely wound around the air duct main body, and the sheet impregnated with the inorganic silicate foam in advance at the manufacturing plant is used as the air duct. Since the air duct obtained by winding it around the main body can be supplied to the construction site, it can be incorporated as it is at the time of concrete pouring, which simplifies and shortens the duct construction and requires no special skill. It can be installed easily and easily, and it is possible to reliably prevent the occurrence of dew condensation due to poor adhesion between the air duct body and the heat insulation layer due to an error in heat insulation work.

Further, it is conceivable that the air duct body is coated directly with the inorganic silicate foam. However, when manufacturing this type, an outer frame is usually arranged outside the air duct body, and The muddy inorganic silicate foam composition is injected into the intermediate space between the duct body and the outer mold, and after the inorganic silicate foam is hardened, it is necessary to remove it from the mold, which is troublesome and mass-produced. On the other hand, the air duct of the present invention has a problem that it is not suitable for, for example, by applying an inorganic silicate foam composition to the air duct body, winding a non-combustible or flame-retardant sheet, and curing it. Since it is good, the productivity is good and the production cost can be reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows an air duct according to an embodiment of the present invention. In this air duct 1, a non-combustible or flame-retardant sheet 3 is wound around an outer peripheral surface of an air duct main body 2 and the sheet 3 is made of an inorganic material. It is formed by forming an impregnation layer 4 of a silicate foam.

Here, as the air duct body 2, for example, a synthetic resin pipe such as a vinyl chloride pipe, a galvanized steel pipe, a metal spiral pipe such as a stainless steel pipe, or a vinyl chloride coated steel pipe can be used, and the inner diameter thereof Is not particularly limited, but is generally 50 to 10
A 00 mm one can be used. The thickness of the air duct body 2 is 1 to 1 when it is made of synthetic resin such as vinyl chloride.
A range of 20 mm, and in the case of a metal tube, a range of 0.05 to 50 mm is suitable.

As the non-combustible or flame-retardant sheet 3, a mixed paper of phosphorylated pulp and glass fiber, aluminum hydroxide mixed paper, glass fiber mixed paper, rock wool, glass fiber,
Single or mixed woven or non-woven carbon fibers can be used. The sheet 3 has a thickness of about 0.1 to 2 mm and can be wound around the air duct body 2 in one to several layers.

The above-mentioned inorganic silicate foam is a cured product of an inorganic silicate foam composition, which is mainly composed of silicate and metasilicate, and which has air entrapped in an inorganic self-hardening composition containing a surfactant. Is. The inorganic self-hardening composition will be described in more detail below.
% Indicates% by weight).

Silicates 15-66
%, More preferably 30 to 60% Kaolin 0 to 28%, more preferably 5 to 20% water soluble magnesium salt 0 to 1%, more preferably 0.2 to 0.8% silicofluoride salt 0 to 20% , More preferably 0 to 5% metasilicate 2 to 58%, more preferably 3 to 30% dicalcium silicate 0 to 20%, more preferably 3 to 15% polyvalent metal salt 0 to 20%, more preferably 3-10% calcium silicate 0-10%, more preferably 0.5-5% ferrosilicon 0-20%, more preferably 0.5-10% portland cement 0-10%, more preferably 0.5. -5% Surfactant 0.1-2%, more preferably 0.1-1% water 0-20%, more preferably 5-15%.

In this case, sodium silicate is used as the silicate, magnesium chloride is used as the water-soluble magnesium salt, sodium silicofluoride is used as the silicofluoride salt, calcium metasilicate is used as the metasilicate, and Nippon Heavy Chemical Industry Co., Ltd. is used as the dicalcium silicate. JMC powder manufactured by K.K., K-Vine manufactured by Nippon Kagaku Kogyo Co., Ltd. as calcium silicate, K Bond manufactured by Teika Co., Ltd. as a polyvalent metal salt, and anionic surfactants such as sodium lauryl sulfate as a surfactant are suitable. Used.

If necessary, a fibrous material such as rock wool or vinylon may be added to the inorganic self-hardening composition,
Fillers such as fly ash, shirasu balloon, perlite, and crushed powder may be contained.

The density of the inorganic silicate foam is 0.3-1.
3 g / cm³, And more preferably 0.5 to 0.8 g / cm³
The range is desirable, and the air should be adjusted to have such a density.
It is good to mix.

As a method for coating and impregnating the above-mentioned sheet with the inorganic silicate foam composition, the sheet is dipped in a mud-like inorganic silicate foam composition to remove excess inorganic silicate foam composition, or brushed. Adopting conventional methods such as dip coating,
The composition can be dipped and applied on one or both sides of the sheet, and then left at room temperature for curing. The amount of the inorganic silicate foam adhered to the sheet is 50
˜2000 wt%, more preferably 300 to 1000 wt%.

Further, when the air duct body is coated with a sheet impregnated with an inorganic silicate foam, the sheet immediately after the composition is dipped or coated is wound around the air duct body to cure the inorganic silicate foam composition. However, the present invention is not limited to this, and may be dipped or applied, then cured, and then wound around the sheet.

[Experiment] A comparative test was conducted on the performance of preventing dew condensation between an air duct covered with a lock sheet impregnated with an inorganic silicate foam and an air duct not covered with the lock sheet.

Using a galvanized steel pipe (spiral steel pipe) having an inner diameter of 150 mm and a thickness of 0.5 mm, one layer of rock wool having a thickness of 5 mm impregnated with 500% silicate foam is wound around the outer peripheral surface of the galvanized steel pipe. It was

These air ducts are operated at 30 ° C. and 60% R
It was installed in the laboratory of H, and 14 ° C. air was circulated in the air duct at a flow rate of 6.5 m / sec to observe the generation of dew condensation water on the outer surface of the duct.

As a result, the dew condensation water dripped after 1 hour on the steel sheet pipe not covered with the lock sheet impregnated with the inorganic silicate foam, whereas the steel sheet pipe covered with the lock sheet impregnated with the inorganic silicate foam was dropped. No condensed water was observed even after 3 hours (the test ended in 3 hours).

Similarly, the air duct is set to 22 ° C. and 50
In a laboratory environment of% RH, the temperature of the air inside the duct was set to 0 ° C. and the generation of dew condensation water on the outer surface of the duct was observed. as a result,
Steel plate pipes not covered with rock wool impregnated with inorganic silicate foam started to drip dew water after 1 hour, whereas steel pipe pipes covered with rock wool impregnated with inorganic silicate foam took 3 hours. No dew condensation was observed even afterwards.

[0027]

According to the air duct of the present invention, the duct forming work can be simplified and the occurrence of dew condensation can be effectively prevented.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

[Explanation of symbols]

 1 Air duct 2 Air duct body 3 Non-combustible or flame-retardant sheet 4 Inorganic silicate foam

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasunari Ueda 1-4-16 Nihonbashi-Bakurocho, Chuo-ku, Tokyo Fujimori Industry Co., Ltd.

Claims (1)

[Claims] 1. An air duct comprising a non-combustible or flame-retardant sheet wound around an outer peripheral surface of an air duct body and an impregnated layer of an inorganic silicate foam formed on the sheet.