JPH08325908A - Heat insulating mat for combustor - Google Patents

Abstract

PURPOSE: To obtain a heat insulating mat for a combustor capable of being formed at a low cost while keeping sufficient heat resistance and heat insulation, and having a strong initial adhesion and able to keep the flexibility and spreadability of an inorganic adhesive when it is adhered on the combustor with the inorganic adhesive. CONSTITUTION: This heat insulating mat 1 for a combustor is composed of a ceramic fiber flocculent body 2 containing a ceramic fiber 2a as a main material and a glass fiber flocculent body 3 containing a glass fiber 3a as a main material. Each of the flocculent bodies 2, 3 is subjected to a needle punch processing in a single state at first to produce a needle mat. Both of the needle mats of the flocculent bodies 2, 3 are layered, and they are treated by simultaneous needling and punching processing in which hooked needles are hit into the mats from the ceramic fiber flocculent body(2)-side. In this process, a part of the ceramic fiber 2a intrudes into the glass fiber flocculent body 3 and entangles with the glass fiber 3a in the flocculent body 3 to form a number of joined parts 4 of fiber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating mat used in various combustion appliances such as boilers, hot water heaters and heaters.

[0002]

2. Description of the Related Art As a heat insulating material for combustion appliances, a single-layer needle mat formed by needle punching a ceramic fiber cotton is generally used. This is because the ceramic fiber has heat resistance to withstand high temperatures up to about 1260 ° C. A single-layer needle mat made of glass fiber cotton-like material can withstand only up to about 650 ° C and is not suitable for the same purpose.

[0003]

However, a needle mat formed by needle punching a ceramic fiber cotton-like material is very expensive as compared with a glass fiber mat. In addition, there is a problem in that when an inorganic adhesive such as a water glass-based or silica sol-based adhesive is adhered to a burning appliance, the initial adhesive force is weak or the adhesive hardens to lose flexibility and extensibility.

The object of the present invention is to solve the above-mentioned problems, to form at low cost while ensuring sufficient heat resistance and heat insulation, and to have strong initial adhesive force when bonding to a combustion appliance with an inorganic adhesive. , To provide a heat-insulating mat for a combustion appliance that can maintain flexibility and extensibility.

[0005]

In order to solve the above-mentioned problems, the heat insulating mat of the burning appliance of the present invention is made of high heat resistant fiber as a main material and has a high heat resistance which is directed to a relatively high temperature side of the burning appliance when in use. The fibrous fibrous body and the medium-heat-resistant fibrous material, which is mainly composed of medium-heat-resistant fiber and is aimed at the relatively low temperature side of the combustion device when used, are superposed, and the hooked needle is attached from the high-heat-resistant fibrous material side. By the simultaneous needle punching performed by driving, a part of the high heat-resistant fiber enters the medium heat-resistant fiber cotton and is entangled with the medium heat-resistant fiber to form a large number of fiber-bonded portions.

Here, the terms "relatively high temperature side" and "relatively low temperature side" mean the side which becomes relatively high temperature and the side which becomes relatively low temperature in the combustion instrument. Also, "high heat resistant fiber"
"Medium heat resistant fiber" also means a fiber having a relatively high heat resistance and a fiber having a lower heat resistance than that. Examples of the high heat resistant fiber include ceramic fiber, silica fiber, quartz fiber, alumina fiber and the like, or a mixture thereof. Examples of the medium heat resistant fiber include glass fiber, rock wool, slag wool and the like, or a mixture thereof.

Both the high heat resistant fibrous material and the medium heat resistant fibrous material may be needle punched into needle mats, or may be laminated before needle punching. Good. In any case,
If simultaneous needle punching is performed after that, an integrated mat is formed.

The thickness of the heat insulating mat after simultaneous needle punching is not particularly limited, but is usually 10 to 100 mm.
Is. Further, the thickness of the highly heat resistant fiber cotton-like material after the simultaneous needle punching may be the same as or different from the thickness of the medium heat resistant fiber cotton-like material. For example, when used in a part exposed to a high temperature, the thickness of the highly heat-resistant fibrous material may be relatively increased. The thickness of the fibrous material may be relatively increased.

The number of hooked needles at the time of simultaneous needle punching, and thus the number of fiber-bonded portions per unit area of the heat insulating mat is preferably 5 to 40 pieces / cm ² . 5 / cm
^If it is less than ² , the binding force of the fiber is weak, and if it exceeds 40 fibers / cm ² , the fiber is likely to be broken and shattered. In addition,
Simultaneous needle punching is preferably performed in the state in which the binder is attached to the high heat-resistant fiber cotton. This is because the high heat resistant fiber is easily broken without the binder. Examples of the binder include a water emulsion of paraffin, a silicon-based surface treatment agent, and other oil agents.

[0010]

According to the heat-insulating mat of the combustion appliance of the present invention, the fiber-bonding portion is formed in the medium heat-resistant fiber cotton body, and the medium heat-resistant fiber cotton body is directed toward the relatively low temperature side of the combustion appliance. Therefore, the high heat resistant fiber cotton is protected from the high heat of the relatively high temperature side, so that the middle heat resistant fiber of the fiber joint does not melt during use. Therefore, the high heat-resistant fiber cotton and the medium heat resistant fiber cotton are not separated. If the fiber-bonded portion is formed in the highly heat-resistant fiber-like cotton body, the medium-heat-resistant fiber of the fiber-bonded portion may be melted by high heat at the time of use, which is not suitable.

When this heat insulating mat is adhered to a combustion appliance, an inorganic adhesive such as water glass or silica sol is applied to the medium heat resistant fibrous material. The initial adhesive force at this time is stronger than in the conventional case where an inorganic adhesive is applied to a ceramic cotton-like body. Moreover, since the medium heat resistant fibrous material is hard to cure even when an inorganic adhesive is applied, flexibility and extensibility can be maintained.

[0012]

EXAMPLES Examples of heat insulating mats for combustion appliances embodying the present invention will be described below with reference to the drawings. FIG.
The heat-insulating mat 1 of the combustion apparatus of the first embodiment shown in (1) comprises a ceramic fiber cotton-like body 2 whose main material is a ceramic fiber 2a and a glass fiber cotton-like body 3 whose glass fiber 3a is a main material. Both the ceramic fiber cotton-like body 2 and the glass fiber cotton-like body 3 are first needle-punched in a single state to form a needle mat.

The two cotton-like bodies 2 and 3 are superposed on each other, and the needles with hooks (not shown) from the ceramic fiber cotton-like body 2 side.
A part of the ceramic fiber 2a enters into the glass fiber cotton-like body 3 by the simultaneous needle punching performed by driving and is entangled with the glass fiber 3a in the cotton-like body 3 to form a large number of fiber connecting portions 4. are doing. The number of fiber bonding portions 4 per unit area of the heat insulating mat 1 is 17 / cm ² . As a result, the thickness of the ceramic fiber cotton-like body 2 is about 8 mm, and the thickness of the glass fiber cotton-like body 3 is about 12 mm.
Then, the ceramic fiber 2 in the fiber connecting portion 4
The ceramic fiber cotton-like body 2 and the glass fiber cotton-like body 3 are integrated by the entanglement of a and the glass fiber 3a.

The ceramic fiber cotton-like material 2 is
Single needle punching and simultaneous needle punching are performed with a paraffin water emulsion as a binder. This binder is blown off by heat after needle punching, but it can be left attached.

The heat insulating mat 1 of this example was used as a test in a gas water heater as follows. That is, while the ceramic fiber cotton-like body 2 is directed toward the relatively high temperature side of the gas water heater (not shown), the glass fiber cotton-like body 3 is directed toward the relative low temperature side, and as shown by the chain double-dashed line in FIG. The glass fiber cotton-like material 3 was coated with the water glass-based inorganic adhesive 5 and adhered to the adhered portion 6 of the gas water heater. The initial adhesive strength at this time was stronger than in the conventional case where the inorganic adhesive was applied to the ceramic fiber cotton. Further, the glass fiber cotton-like material 3 maintained its flexibility and extensibility even when the inorganic adhesive 5 was applied.

When the gas water heater was actually operated, the heat insulating mat 1 exhibited heat resistance and heat insulating properties which were completely the same as those of the conventional ceramic fiber single layer heat insulating material. That is, transmission of high heat on the relatively high temperature side is sufficiently blocked by the ceramic fiber cotton-like material 2 (of course,
Further, although it was also blocked by the glass fiber cotton-like body 3, the glass fiber cotton-like body 3 including the glass fiber 3a of the fiber connecting portion 4 did not melt. Therefore, the ceramic fiber fluff 2 and the glass fiber fluff 3
And never separated.

As described above, according to the heat insulating mat 1 of this embodiment, since the inexpensive glass fiber cotton-like material 3 is used together while ensuring sufficient heat resistance and heat insulating property, it is formed at a lower cost than the conventional one. it can.

Next, in the heat insulating mat 21 of the combustion instrument of the second embodiment shown in FIG. 2, both the ceramic fiber cotton-like body 2 and the glass fiber cotton-like body 3 before needle punching are superposed. From the above, only the point that the simultaneous needle punching was performed, and the thickness of the ceramic fiber cotton-like body 2 after the processing was about 12 mm, and the thickness of the glass fiber cotton-like body 3 was about 8 mm, Is different from Therefore, the same parts as those in the first embodiment are designated by the common reference numerals in FIG. 2 and their explanations are omitted.
This example also has the same effect as the first example, and has a slightly higher degree of heat resistance and heat insulation.

The present invention is not limited to the configuration of the above-described embodiment, but may be embodied with appropriate modifications within the scope not departing from the spirit of the invention, for example, as follows. (1) Applying or impregnating a heat-resistant sealing agent on the surface of the highly heat-resistant fibrous material. As the sealing agent, ceramic powder (for example, silica, alumina,
Examples thereof include a ceramic coating material mainly composed of mullite) and an inorganic binder such as silica sol and alumina sol. (2) Overlaying another medium heat resistant fiber cotton on the medium heat resistant fiber cotton and subjecting the three layers to needle punching simultaneously.

[0020]

EFFECTS OF THE INVENTION Since the heat insulating mat for a combustion appliance of the present invention is constructed as described above, it can be formed at a low cost while ensuring sufficient heat resistance and heat insulation, and is bonded to the combustion appliance with an inorganic adhesive. In this case, it has an excellent effect that the initial adhesive strength is strong and the flexibility and the stretchability can be maintained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a heat insulating mat for a combustion appliance according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of a heat insulating mat for a combustion appliance according to a second embodiment of the present invention.

[Explanation of symbols]

 1 Insulation Mat 2 Ceramic Fiber Cotton 2a Ceramic Fiber 3 Glass Fiber Cotton 3a Glass Fiber 4 Fiber Bonding Part 5 Inorganic Adhesive 6 Adhered Part

Claims (1)

[Claims] 1. A cotton-like material made of high heat-resistant fiber as a main material and directed to the relatively high temperature side of a combustion appliance when used, and medium-heat resistant fiber as a main material and oriented to the relatively low temperature side of a combustion appliance when used. Intermediate heat-resistant fiber cotton-like material is overlaid, part of the high heat-resistant fiber is the middle heat-resistant fiber by simultaneous needle punching performed by driving a hooked needle from the side of the high heat-resistant fiber cotton-like material. A heat insulating mat for a combustion appliance, characterized in that it penetrates into a cotton-like body and is entangled with the medium heat resistant fibers to form a large number of fiber joints.