JPS6172819A - Bagform mat for seal for exhaust gas purifying device - Google Patents

Abstract

PURPOSE:To close a gap between a mat and a honeycomb catalyst, around with the mat is wound, and to prevent leak of exhaust gas, by a method wherein a heat resistant seal material is wrapped with a heat resistant cover so as to prevent leak thereof to forms a bagform mat for seal having cushion properties. CONSTITUTION:A bagform mat 1 for seal is formed such that a heat resistance seal material 3 is wrapped with a heat resistant cover 2 so as to prevent leak thereof. In which case, a bag, formed by a metallic foil, a wire net with fine meshes, carbon fiber cloth, is used as the cover 2. Heat resistant fiber, wire materials, powdery materials, are used as the seal material 3. Further, cushion properties are provided for the mat 1 to prevent the occurrence of unevenness in size and production of vibration. In operation, after the mat 1 is wound around the whole in a direction A of length of the side peripheral part of the honeycomb catalyst 4, the catalyst is contained in the expansion part of a semisplitlike case 5 to form a purifying device. This enables enclosure of a gap between the honeycomb catalyst 4 and the case 5, and permits prevention of leak of exhaust gas.

Description

[Detailed Description of the Invention] [Field of Application] The present invention relates to a sealing bag-shaped mat with excellent airtightness that is used by being wound over the entire length of a honeycomb catalyst in the lateral circumferential direction in an exhaust gas purification device. It is.

[Conventional technology]

Conventionally, a cushion body was formed by wrapping a wire mesh around the periphery of both ends of a honeycomb catalyst for purifying automobile exhaust gas, etc., which was made of a cylinder body made of Cefmic or the like integrally molded into a honeycomb shape and a catalyst. An automobile exhaust gas purification device is known in which a corrugated wire mesh is wound around the central part of the honeycomb catalyst, and the wire mesh is housed in the large part of the case.

The cushion body and the corrugated wire mesh accommodate large variations in the dimensions of the honeycomb catalyst, elastically support it, protect it from vibration, and prevent leakage of exhaust gas from between the case and the honeycomb catalyst. It's useless.

[Problems to be solved]

However, although the conventional method using cushioning and corrugated wire mesh has excellent elastic support, the rate of exhaust gas leakage reaches 5 to 7 inches, and the gap between the case and the honeycomb catalyst increases. There was a problem with poor airtightness.

[Means for solving problems]

The present invention was made with the aim of solving the above-mentioned problem, and is a seal having cushioning properties, which is made by enclosing a heat-resistant V-μ material with a heat-resistant cover to prevent the sealant from leaking. The present invention provides a bag-shaped mat for use in a honeycomb catalyst, which is used by being wrapped around the entire circumferential length of a honeycomb catalyst.

〔Example〕

As shown in FIG. 1, the sealing bag-shaped mat 1 of the present invention is comprised of a heat-resistant sealing material 8 enclosed in a heat-resistant cover 2 to prevent the sealing material from leaking. As a heat-resistant cover, for example, metal foil, fine-mesh wire mesh,
A bag made of carbon fiber cloth or the like is preferably used, but the bag is not limited to this, and may be a sheet-like bag that wraps around the sealing material. In addition, heat-resistant sealing materials include, for example, asbestos, rock wool, heptaramic fiber, carbon fiber, glass fiber, Suffular μ, heat-resistant fibers such as metal fibers, heat-resistant wire materials such as coils with a small outer diameter, Sand, μsium carbonate, metal powder, heat-resistant powder such as micro balloons, etc. are used. It is desirable to encapsulate the heat-resistant powder in a bag made of a film-like material such as metal foil in order to prevent leakage.

7-/vJ@bag-shaped pine) 1 of the present invention can be applied to a purification device by dividing the mat into small bag-shaped sections 1a as shown in Fig. 2 to prevent the sealing material from being biased. This is desirable in terms of sealability when

In addition, the sealing bag-shaped mat l has cushioning properties, which makes the honeycomb catalyst vibration-resistant while allowing for variations in the dimensions of the honeycomb catalyst, and prevents excessive pressure that may cause damage to the honeycomb catalyst. It is necessary to store it in a case so that it does not get damaged. Further, it is desirable that the sealing bag-shaped mat has enough flexibility to be easily wrapped around the side shoulder portion of the honeycomb catalyst.

A purifying device using the bag-shaped pine for sea μ of the present invention) 1 is produced, for example, as follows.

That is, as shown in FIG. 8, the sealing bag-shaped mat 1 of the present invention is applied over the entire lengthwise direction (5) of the side shoulder part of the honeycomb contact [4] integrally molded into a cylindrical shape, and also in the side circumferential direction. A purifying device is manufactured by wrapping the entire length of the wafer and collecting it in the enlarged part of the half-shaped case 75. By wrapping the sealing bag-shaped mat all the way around the length of the honeycomb catalyst in the lateral circumferential direction, the honeycomb catalyst can be housed and maintained in the case without being damaged by vibration.

On the other hand, as shown in Fig. 4, a sealing bag-shaped mat is wrapped around a part of the side shoulder of the honeycomb catalyst in the length direction and the entire circumferential length of the side shoulder. It is also possible to have a purification device in which a sealing bag-shaped mat is used only in a part of the filtration system. Note that 6 is a cushion body formed by stacking wire mesh in multiple layers, and 7 is a corrugated wire mesh.

〔Effect of the invention〕

According to the sealing bag-shaped mat of the present invention, the gap between the honeycomb catalyst and the case in the exhaust gas purification device can be airtightly closed, and leakage of exhaust gas can be more reliably prevented.

Furthermore, the sealing bag-shaped mat of the present invention has excellent vibration resistance and can be wrapped around the entire length of the honeycomb catalyst in the lateral circumferential direction, thereby effectively preventing damage to the honeycomb catalyst due to vibration. Furthermore, since it has heat insulating properties, it is possible to effectively prevent cooling of the honeycomb catalyst depending on the installation width of the sealing bag-shaped mat, and maintain the high rate processing capacity of the honeycomb catalyst for exhaust gas. becomes possible.

[Application examples, comparative examples]

Application example 1 Rock wool is sealed in a copper foil bag with a thickness of 70 μm on the side shoulder of a ceramic honeycomb catalyst with a diameter of 10 c+a, a length of 20 ccm, and a passing air flow rate (pressure difference of 2276 [1111 water columns)] of 40001/min. By wrapping the formed sealing bag-shaped mat (width 16 ca, length #7 cm, thickness 5.0 mm) and storing it in a stainless steel case, an exhaust gas purification device (Fig. 8 specifications) is created. was created.

In addition, the gap between the outer periphery of the honeycomb catalyst and the inner surface of the stainless steel case in the purification device was 8.7 am.

In addition, for the evaluation test, both ends of the honeycomb catalyst were closed with stainless steel wire in advance to prevent ventilation.

Next, the above exhaust gas purification device was installed in a constant temperature chamber at 600°C, and one opening of the case of the purification device was connected to a vacuum pump while applying 20G of vibration to it. 276ffII inside the purification device by operating the
11. Set the water column to a reduced pressure state, measure the amount of air flowing in from the other opening of the case in this state, evaluate this measured value as the leakage amount q (1/min), and calculate the sealing ability (fog) using the following formula. I asked for it.

Sealing ability (%) = -x l 0 0 The sealing ability 10 minutes and 10 hours after the start of the test is shown in the table.

Application Example 2 An exhaust gas purification device was manufactured in the same manner as Application Example 1, except that a sealing bag-like mat made by filling a bag made of quartz glass fiber Kuronu with a thickness of 1 mm with ceramic fiber cotton was used. I researched Noh.

The results are shown in the table.

Application Example 8 A cushion body consisting of 6 layers of wire mesh formed by knitting stainless steel wire with a diameter of 0.25 mm and having a mesh size of 10 meshes was provided on the periphery of both ends of a honeycomb catalyst. A wire mesh with a 7-mesh mesh formed by knitting 25 mm stainless steel wire into a cylindrical shape is flattened, and the corrugation is a wire mesh (long) with a corrugated shape (difference between peaks and valleys of about 1 ctn) that has been compressed. length 11 cm) and width 5
An exhaust gas purification device (Fig. Specifications) were prepared and their sealing ability was investigated. The results are shown in the table.

Comparative Example An exhaust gas purification device was fabricated in the same manner as in Application Example 3, using a corrugated wire mesh as the part where the sealing bag-shaped mat was used, and its sealing performance was investigated. The results are shown in the table.

Seal Noh (96) Application example 1 1.0 1.2 /21.1 1.0 81.8 2.0 Comparative example 7.8 7.1

[Brief explanation of drawings]

Fig. 1 is an explanatory sectional view of an embodiment of the sealing bag-shaped mat of the present invention, Fig. 2 is a perspective view of another embodiment, and Figs. 8 and 4 are purification devices to which the sealing bag-shaped mat is applied. FIG. 2 is a cross-sectional view showing a structural example of. 1: Niji-μ bag-shaped mat, 2: heat-resistant cover, 8: heat-resistant sealing material, 4: honeycomb catalyst, 5: case.

Claims (1)

[Claims] 1. In an exhaust gas purification device in which an integrally formed honeycomb catalyst is housed in a case, a heat-resistant sealing material is wrapped around the entire circumferential length of the honeycomb catalyst with a heat-resistant cover. A sealing bag-shaped mat with cushioning properties that prevents leakage.