JPH0634122A - Seal member for combustion machine - Google Patents

Abstract

PURPOSE:To prevent combustion gas from being leaked for a long period of time under an effect attained by a new shape of a seal material between a heat radiation pipe of an FF heater and a easing, material quality and shape. CONSTITUTION:There is provided a ring-like molded product in which one surface comprised of ceramic fiber and non-organic binder is provided with a groove in its circumferential direction. There is further provided a seal member of high air-tightness comprised of ceramic fiber of 80 to 99wt.% sepiolite of 0.5 to 10wt.%, and other non-organic binders such as monmorillonite, corodial silica and water glass and the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing material for preventing harmful exhaust gas leaking from a connecting portion of a radiating pipe into a room in an outdoor forced air supply / exhaust type (generally called FF type) heater. .

[0002]

2. Description of the Related Art The properties required for a sealing material between a heat radiating pipe and a casing are, first of all, heat resistance to withstand a temperature of around 800.degree.
Second, airtightness so that combustion gas does not leak from the connection of the heat radiating pipe, third, flexibility that fits closely to both the radiating pipe and the opposing casing, and fourth, the weight of the radiating pipe and vibration during combustion. Mechanical strength that can withstand a long period of time is desired. The most suitable material for the above characteristics is an asbestos papermaking product, which is formed into a ring shape, or cut out into a ring shape from a papermaking sheet, or
It has been punched and used.

However, asbestos fiber has been socially recognized as a causative agent of lung cancer and is being regulated. Especially, when it is mainly used at home such as a heater, it cannot be used in the future.

[0004]

The asbestos conventionally used has excellent airtightness due to the properties peculiar to the material, but cannot be used because of its carcinogenicity. There is a demand for a safe and highly airtight seal material that replaces asbestos, and the present invention proposes a seal material for a radiator pipe of a heater.
Ceramic fibers have more heat resistance than asbestos, are relatively inexpensive, and have no carcinogens. In addition to the property of the material, the present invention proposes a shape suitable for holding the radiant heat radiating pipe of the heater in terms of the shape of the sealing material.

As the ring-shaped sealing material for supporting the heat radiating pipe, it is desirable that the heat radiating pipe is not displaced. The sealing material itself is fixed by the heater casing,
Since the radiating pipe is only loaded from above and below via the sealing material, the radiating pipe is displaced due to vibrations, the sealing material is worn, and the combustion gas leaks.

Based on the above assumptions, the present invention proposes a ring-shaped sealing material having a groove for fixing a heat radiating pipe. Further, in claim 2, the ceramic fiber and the binder are made into a slurry in water. The present invention proposes a structure of a material having excellent airtightness in the case of forming a paper in a ring shape.

[Means for Solving the Problems]

In the present invention, a sealing material which has been a flat ring-shaped material of asbestos in the past is made of safe ceramic fiber and an inorganic binder, and a ring-shaped material provided with a groove for fixing a heat radiation pipe in a circumferential direction. By doing so, the stability of the heat radiation tube to be held is ensured. If the radiating pipe is fixed to the groove-shaped sealing material, the radiating pipe will not be displaced or worn even if there is vibration, and the leakage of combustion gas can be kept low. As a method of molding the sealing material of the present invention, the ceramic fiber and the binder are stirred in water, molded with a suction type through a net, and dehydrated and dried. The suction type structure sucks in the gap of the cylindrical double tube, the lower part of the gap is the suction part and the projections corresponding to the grooves are provided, and after the suction molding, the mold is removed from the mold along the cylindrical tube by the air cylinder. A slide is preferable.

Next, the shape and effect of the groove will be described. It is desirable that the groove shape is the same as the end shape of the heat dissipation tube because the contact area can be increased. Considering the effect of radiation, the heat radiating tube is generally made of heat-resistant glass, and its end portion is polished into a U-shape. Further, the thickness of the heat radiating pipe is in the range of 3 to 10 mm, and the width of the sealing material is preferably a value obtained by adding 4 to 10 mm to the thickness of the heat radiating pipe. If it is 4 mm or less, that is, if it is 2 mm or less on one side of the heat radiating tube, there is a problem in durability against vibration and the like, and if it is 10 mm or more, it is not preferable from the viewpoint of aesthetics. The thinner the groove portion of the sealing material, the smaller the air passage area and the higher the airtightness, but a thickness of 5 to 10 mm is suitable from the viewpoint of strength. The groove width may be equal to or wider than the thickness of the heat radiating tube by 1 to 2 mm so as to fit the heat radiating tube, and the groove depth is preferably about half of the thickness of the heat radiating tube. The effect of the groove is to prevent displacement of the heat dissipation pipe due to vibration etc.In the case of a flat plate seal material, make the protrusion height of the fitting part of the casing fixing the seal material longer than the thickness of the seal material. , The protrusion of the casing was used to stop the shift. However, this method shortens the life of the heater due to the high temperature of the casing due to thermal deformation and corrosion. In the present invention, the height of the protrusion of the fitting portion of the casing can be set to about 3 mm, and the temperature of the casing can be lowered and the life can be extended. Next, claim 2 having high airtightness will be described.

The wet-fabricated molded article of ceramic fiber is prepared by adding the fiber and colloidal silica to water and stirring the mixture to gel the colloidal silica and further add a coagulant to fix the colloidal silica to the fiber. It is common.
The ring-shaped molded body obtained by molding the above slurry into the shape of claim 1 had large air leakage. As a result of various tests, the present inventor has found that the case where the sepiolite powder is added to the slurry and molded is the most airtight.

The ceramic fiber has a diameter of about 1 to 5 μm and a length of 0.1 to 10 mm, whereas the colloidal silica has a diameter of 1 to 5.
It has a spherical shape of 0 to 30 nm, and sepiolite has a length of 1 to 1.
The diameter is about 5 μm to about 20 nm at about 0 μm. That is, although both have the same diameter, it is considered that sepiolite has a length of about 500 times and thus has a large air passage resistance. However, since sepiolite has no binding force, it is necessary to add a small amount of clay mineral, and / or colloidal silica, and water glass as a binder, and fix it with a flocculant. The minimum amount that sepiolite is effective is 0.5
If it exceeds 2 to 5% by weight, and if it exceeds 10% by weight, it takes a long time for dehydration due to clogging and the productivity is remarkably reduced.

Clay minerals such as montmorillonite, colloidal silica, or water glass are not always necessary for obtaining airtightness, but at least 0.5% by weight for obtaining long-term durability and constant strength, Desirably 2 to 7% by weight
Is necessary. If it exceeds 10% by weight, the surface becomes hard,
Adhesion between the heat radiation pipe and the casing is reduced. The above components and ceramic fibers are put into water, stirred and sufficiently dispersed, and then van sulphate earth and a polymer flocculant are added as a fixing agent to form a uniform aggregate of the fibers and fine particles. The aggregate is first aggregated into large flocs, but it is redivided into small flocs by stirring and settles when stirring is stopped. The supernatant becomes transparent and the separation of fibers and fine particles does not occur.

The amount of bansulfuric acid soil added is such that the PH of the slurry is 6.5 to 7.5, and the polymer flocculant is preferably polyacrylamide, cation treated with starch or the like, and the total solid content. The addition amount of 0.01 to 0.5% by weight is desirable. If it is less than 0.01%, aggregation is insufficient, and if it exceeds 0.5%, discoloration, odor, and smoke are generated when heated.
Product value is inferior.

The bulk specific gravity of the molded product suction-molded with the above composition is 0.15 to 0.35 g / cm ³ . The slurry concentration, which is the ratio of the total solid weight to the weight of water, is 0.5%
Then, the bulk specific gravity of the molded product is 0.30 to 0.35 g /
As a result, a compact and rigid molded body having a density of cm ³ can be obtained, and if the slurry concentration is 2%, the bulk specific gravity is 0.15 to 0.20 g / cm ³ . The optimum bulk specific gravity is 0.20 to 0.30 g / cm ³ , and a slurry concentration of 1.0 to 1.5% is suitable.
If the bulk specific gravity is 0.2 g / cm ³ or less, the amount of air passing through the molded body increases, and since it is soft, the adhesion is good, but the strength and durability are poor. On the other hand, if the bulk specific gravity is 0.3 g / cm ³ or more, the surface becomes hard and the adhesiveness deteriorates, and unless a load is applied until the molded body is crushed, air leakage from the gap is not suitable. With a ring-shaped molded body of 0.2 to 0.3 g / cm ³ , there is no leakage from the gap and no deformation or crushing of the molded body under a load of 150 g / cm ² .

[0014]

【Example】

(Example 1) Average fiber diameter 3 μm and length 0.1 to 10 m
100 parts by weight of the aluminosilicate ceramic fiber of m are dispersed in 10,000 parts by weight of water, and 3 parts by weight of Adeplus (manufactured by Takeda YKK) as sepiolite.
Snowtex-30 (manufactured by Nissan Chemical Industries KK) as colloidal silica is dispersed and stirred in an amount of 3 parts by weight in terms of solid content. After sufficiently stirring, 0.5 part by weight of vanadium sulfate was added, and 0.05 part by weight of DCR (manufactured by Misawa Ceramic Chemical KK), a cationic polymer flocculant, was added to agglomerate to make fine flocs. After that, the stirring was stopped and the suction mold was put into the slurry for suction molding. The mold was taken out of the slurry, dehydrated, demolded and dried.

Example 2 100 parts by weight of the same ceramic fiber as in Example 1 was dispersed in 10,000 parts by weight of water,
1 part by weight of AED PLUS and 5 parts by weight of Snowtex-30 in terms of solid content are added and stirred. Next, van sulphate soil 0.
Add 8 parts by weight, and further add DCR to 0.05 in terms of solid content.
Add parts by weight to agglomerate. Thereafter, a molded body is obtained in the same manner as in Example 1.

(Comparative Example) 100 parts by weight of the same ceramic fiber as in the example is dispersed in 10,000 parts by weight of water, and 6 parts by weight of colloidal silica is dispersed and stirred in a solid content. After sufficient dispersion, 0.6 part by weight of vanadium sulfate and DCR of coagulant
0.05 part by weight of solid content is added to agglomerate and molded and dried as in the example. The amount of air leakage of the ring-shaped compacts obtained in the above Examples and Comparative Examples was measured. First measurement result
Shown in the table.

[0017]

[Table 1]

[0018]

According to the present invention, the harmful exhaust gas leaking into the room from the connection portion of the radiant heat radiation pipe of the outdoor forced air supply / exhaust heater is reduced, the heat resistance is excellent, and the radiant heat radiation pipe can be fixed by the groove. A sealing material can be provided.

Claims (2)

[Claims] 1. A ring-shaped molded article, which is a sealing material for a radiating pipe used in a heater for forced forced air supply / exhaust with fluid fuel, and which is provided with a groove on one side of a ceramic fiber and an inorganic binder in a circumferential direction. 2. Ceramic fibers of 80 to 99% by weight, sepiolite of 0.5 to 10% by weight, and one or more of clay minerals such as montmorillonite as an inorganic binder, colloidal silica, and water glass in an amount of 0. The sealing material according to claim 1, which has a high airtightness and comprises 5 to 10% by weight.