JP5049468B2 - Insulated container and manufacturing method thereof - Google Patents

Description

  The present invention relates to a heat insulating container used in an industrial furnace, an incinerator, a power plant, and the like, and a method for manufacturing the same. In particular, the present invention relates to a vacuum heat insulating container for a vacuum heat insulating panel and a method for manufacturing the same.

  In recent years, high-performance heat insulation panels are required for energy saving and cost reduction. In the fields of semiconductors, electronic devices and the like, there is a particular need for heat-insulating panels that do not generate dust as the performance of components increases in size and size. In order to meet such a demand, various vacuum heat insulating containers and methods for manufacturing the same have been proposed.

  For example, a fiber-like or powder-like discontinuous spacer is placed on the box-shaped part of the outer plate drawn into a shallow box shape, covered with another outer plate, and drawn with the outer peripheral part of the outer plate of the lid. After airtight welding the flange part of the outer plate over the entire circumference, it is in a vacuum heat insulating material that is sealed by vacuuming the inside, and the side wall portion of the shallow box-shaped diaphragm of the outer plate is made to the thickness of the other part On the other hand, a metal container for a vacuum heat insulating material which is made thinner by 30% or more is disclosed. In this document, as an example, the heat insulating material is the same as a non-continuous spacer of glass fiber placed on a box-shaped portion of an outer plate made of a stainless steel plate having a thickness of 0.2 mm drawn into a shallow box shape. Cover with another outer plate made of material, seal the outer periphery of the outer plate of the lid and the flange of the drawn outer plate by seam welding over the entire circumference, then inhale from the connecting pipe and vacuum the inside After that, the manufacturing method is explained when the pipe is sealed (see Patent Document 1).

In addition, it comprises a large-diameter cylindrical outer body, a small-diameter cylindrical inner body, and a bottom member fitted inside the cylindrical inner body, and the gap between the cylindrical outer body and the cylindrical inner body is vacuum insulated. In the manufacturing method of the metal thermos, the bottom member is fitted inside the cylindrical inner body, the joining piece of the bottom member and the end portion of the cylindrical inner body are welded, and then the cylindrical inner body A predetermined position is pressed inwardly to provide a recess, and then the cylindrical inner body integrated with the bottom member is coaxially arranged in the cylindrical outer body with a gap interposed and disposed. Then, the end portions of the cylindrical inner body and the cylindrical outer body are welded except for the position of the recess, and then an appropriate wire and an appropriate brazing material are arranged in the recess. A method of vacuum-sealing a cylindrical outer body and a cylindrical inner body by vacuum heating according to the method is disclosed. Accordingly, since there are few (small) portions to be vacuum-sealed by the brazing material, a metal vacuum bottle with an excellent vacuum state is obtained (see Patent Document 2).
Japanese Patent Laid-Open No. 11-11454 (paragraphs [0012] and [0020], FIG. 1 in the detailed description of the invention) JP 7-195135 A (paragraphs [0007], [0008], FIG. 4, FIG. 5 in the detailed description of the invention)

  However, in the former prior art, the vacuum vessel is sealed by seam welding. In the latter prior art, a brazing material is used and a brazing material reservoir is formed and sealed. When a thin metal plate (for example, 0.5 mm or less) is welded by using these seam welding and brazing materials, there is a problem that a sealing defect is likely to occur due to deformation of the metal plate. When a panel is made of a metal that can withstand high temperatures, a metal plate that is as thin as possible is selected as the material in order to suppress heat conduction at the top and bottom surfaces. It is easy to produce.

  Then, this invention makes it a subject to provide the heat insulation container with few airtight defects with respect to the welding containing the brazing of a metal plate, and its manufacturing method.

  In order to solve the above-described problems, the present invention includes a first exterior plate and a second exterior plate that is disposed to face the first exterior plate and forms an airtight portion between the first exterior plate and the first exterior plate. In the heat insulating container, a joint formed on an edge of the first exterior plate, a joint formed on an edge of the second exterior plate, and the other joint formed by extending one of the joints. And a brazing material interposed between the joint portions and / or the bent portion and the other joint portion. As a result, it is possible to obtain a heat-insulated container having few airtight defects with respect to welding including brazing of a metal plate.

  Moreover, if the heat insulation container whose vacuum degree of the said airtight part is 0.1-100 Pa, a high heat insulation effect will be acquired.

  Further, at least one of the first exterior plate and the second exterior plate is a metal plate having a thickness of 0.1 to 0.6 mm, preferably 0.2 to 0.5 mm, and the airtight portion is formed by drawing. If the heat insulation container in which the space is formed is obtained, a high heat insulation effect by a thin metal plate can be obtained.

  Moreover, if it is set as the heat insulation container in which the heat insulating material which consists of a low heat conductivity material below 0.1 W / (m * K) is inserted in the airtight part of the said heat insulation container, a high heat insulation effect will be acquired.

  In addition, after forming the airtight space forming portion on the first exterior plate and / or the second exterior plate by drawing, the joint provided on the edge of any one of the exterior plates is 1 to 10 mm from the end in advance. A foil-like brazing material is fixed by spot welding in the range of the above, and the crimping process is performed by folding back the folded portion sandwiching the other joined portion formed by extending one of the joined portions. Or it is set as the manufacturing method of the heat insulation container sealed by heat-treating in the atmosphere furnace which can prevent oxidation on the stainless steel surface. Thereby, the manufacturing method of the heat insulation container with few airtight defects with respect to the welding containing the brazing of a metal plate can be obtained.

  As described above, according to the present invention, it is possible to obtain a heat-insulating container with few airtight defects and a method for manufacturing the same for welding including brazing of metal plates. In particular, it is possible to produce a low-cost vacuum insulated container free from airtight defects using a thin stainless plate.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 and 2 relate to the first embodiment. FIG. 1 is a longitudinal sectional view of a heat insulating container, and FIG. 2 is a partially enlarged view thereof.

  The heat insulating container 10 includes a first exterior plate 1 and a second exterior plate 2 that is disposed to face the first exterior plate and forms an airtight portion 5 between the first exterior plate 1. A joining portion 1a formed on the edge of the first exterior plate 1, a joining portion 2a formed on the edge of the second exterior plate 2, and the other joining portion 2a formed by extending one joining portion 1a. The brazing material 4 is interposed between the bent portion 1b to be sandwiched and between the joint portions 1a and 2a and between the bent portion 1b and the other joint portion 2a. The hermetic part 5 is composed of a hermetic space forming part 2 c (which is composed of a hermetic space forming intermediate part 2 d and a hermetic space forming bottom part 2 e) provided in the second outer plate 2, and the first outer plate 2. Is done. A heat insulating material 3 is accommodated in the airtight portion 5.

  The heat insulating container 10 is manufactured as follows.

  That is, an airtight space forming portion 2c is provided by drawing on a stainless steel plate having a small thermal conductivity to form the second exterior plate 2, and a heat insulating material such as glass wool fiber is provided in the airtight portion 5 constituted by the airtight space forming portion 2c. 3, a stainless steel first exterior plate 1 is combined, and a joint 1 a, 2 a around each of the first and second exterior plates 1, 2 is sealed by brazing with a brazing material 4. Make it. At this time, the foil-like brazing material 4 is fixed to the end portion of the joint portion 2a of the one exterior plate 2 of the two exterior plates 1 and 2 in advance within a range of 1 to 10 mm from the end portion by spot welding. The bent portion 1b extended from the joint portion 1a of the exterior plate 1 is folded back so as to wind the end portion of the joint portion 2a, and after caulking, prevents oxidation of the vacuum furnace or stainless steel surface. Seal by heat treatment in a possible atmosphere furnace.

  Next, a second embodiment will be described with reference to FIG. FIG. 3 is a partially enlarged longitudinal sectional view of the heat insulating container and corresponds to FIG. 2 of the first embodiment.

  The differences from the first embodiment are all shown in FIG. The reference numerals of the constituent parts are shown by adding 10 to the reference numerals of the corresponding constituent parts of the first embodiment. The joining portion 11a of the first exterior plate 11 has the brazing material 14 fixed to the end thereof by spot welding, and further, the joining portion 12a of the second exterior plate 12 and a bent portion 12b provided extending from the joining portion 12a. Is folded and sandwiched so as to wind the end portion of the joint portion 11a. Thereafter, caulking is performed. Others are the same as those in the first embodiment.

  Various embodiments are possible for the spot welding arrangement of the foil-like brazing filler metal 4 shown in the first embodiment and the second embodiment. These forms will be described with reference to the explanatory view showing the form of brazing in FIG. The column in the first row of the explanatory diagram shows the vertical cross-sectional shape of the end portions of the first and second exterior plates. Thus, in each table frame, the longitudinal cross-sectional shape of arrangement | positioning of the edge part of 1st and 2nd exterior board and brazing material is shown like a model. Columns in the first row are created separately when the bent portion 1b is provided on the first exterior plate 1 and when the bent portion 12b is provided on the second exterior plate 12. The column of the second row shows the arrangement state of the brazing materials 4 and 14 in one of the joint portions 2a and 11a without the bent portion of the exterior plate having a shape corresponding to the column of the first row. The column of the third row shows the state where the bent portions 1b and 12b of the first or second exterior plate 1 and 12 are raised corresponding to the column of the second row. The fourth line column shows the state of crimping corresponding to the third line column.

  With any brazing material arrangement, an insulated container with very few airtight defects was obtained. In particular, the arrangement of the brazing materials 4 and 14 on both surfaces of the joint portions 2a and 11a can surely reduce airtight defects.

  In the above embodiment, a brazing material defined in JIS standards can be appropriately selected and used as the brazing material. When the exterior plate is a stainless steel material, a copper base, an aluminum base, a nickel base, and a silver base brazing material are used. A nickel-based brazing material is preferable from the viewpoint of heat resistance and corrosion resistance.

  Furthermore, although the vacuum degree of the airtight part was 0.1-100 Pa, the high heat insulation effect was acquired.

  Moreover, although the thickness of at least one of the 1st exterior plate and the 2nd exterior plate was made into the metal plate of 0.2-0.5 mm, the high heat insulation effect by the thin metal plate was acquired. In particular, when the portion of the airtight space forming intermediate portion 2d of the second exterior plate was thinned, a high heat insulating effect was obtained.

  In addition, a heat insulating material made of a low thermal conductivity material having a thermal conductivity of 0.1 W / (m · K) or less was inserted into the hermetic portion of the heat insulating container, and a high heat insulating effect was obtained.

  Although the two embodiments have been described above, in the present invention, the material of the metal plate includes stainless steel, aluminum, aluminum alloy, and copper alloy, but stainless steel is preferable from the viewpoint of low thermal conductivity.

  In the present invention, the thickness of the metal plate may be 0.05 to 10 mm, but at least the plate thickness closer to the heat source is preferably as thin as possible to reduce heat conduction, but is too thin. However, since the expected strength cannot be obtained, it is specifically 0.05 to 1 mm, preferably 0.1 to 0.6 mm, and more preferably 0.2 to 0.5 mm.

  Furthermore, the atmospheric pressure (degree of vacuum) of the inner space of the heat insulating container will be described. Vacuum sealing means that the air pressure of the inner space of the heat insulating container is 0.1 to 1000 Pa. In the present invention, 100 to 600 is used. The temperature is preferably 0.1 to 10 Pa, more preferably 0.1 to 1 Pa in order to ensure heat insulation performance in a relatively high temperature region such as ° C.

  The heat insulating material that can be inserted into the inner space of the heat insulating container has a thermal conductivity of 0.1 W / (m · K) or less, preferably 0.05 W / (m · K) or less, more preferably 0.02 W / (m · K) or less, for example, glass fiber heat insulating material, ceramic fiber heat insulating material, calcium silicate heat insulating material, rock wool, ceramic porous body, honeycomb material, metal multilayer reflector, etc. In the present invention, it is preferable to use a ceramic porous body or a ceramic fiber heat insulating material from the viewpoint of low thermal conductivity.

  Regarding the temperature at the time of brazing, in the present invention, for example, the brazing material may be melted at a temperature exceeding the liquidus of the brazing material (for example, 500 to 1100 ° C.) to perform brazing welding.

  Specifically, it is 600 to 1100 ° C. for a copper base, 500 to 700 ° C. for an aluminum base, 800 to 1100 ° C. for a nickel base, and 550 to 850 ° C. for a silver base.

  The atmosphere capable of preventing oxidation in the atmosphere during brazing is not particularly limited as long as it is an oxygen-free atmosphere. Specifically, hydrogen gas, carbon monoxide gas, carbon dioxide gas, nitrogen gas, ammonia decomposition It means an atmosphere of gas or inert gas (Ar, He). In the present invention, it is desirable to use hydrogen gas or stainless steel in which stainless steel can be easily reduced.

  INDUSTRIAL APPLICABILITY The present invention is useful as a vacuum heat insulating container for a vacuum heat insulating panel used in an industrial furnace, an incinerator, a power plant and the like, and a method for manufacturing the same.

It is a longitudinal cross-sectional view of the heat insulation container in 1st Embodiment by this invention. FIG. 2 is a partially enlarged view (partially enlarged longitudinal sectional view) of FIG. 1. It is a partially expanded longitudinal cross-sectional view of the heat insulation container in 2nd Embodiment by this invention. It is explanatory drawing which shows the form of the various brazing processes in this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 1st exterior plate, 1a joint part, 1b bending part, 2nd exterior plate, 2a joint part, 2c airtight space formation part, 2d airtight space formation bottom part, 2e airtight space formation bottom part, 3 heat insulating material, 4 brazing material DESCRIPTION OF SYMBOLS 5 Airtight part, 10 Thermal insulation container, 11 1st exterior board, 11a joined part, 12 2nd exterior board, 12a joined part, 12b bending part, 14 brazing material.

Claims (3)

In a heat insulating container provided with a first exterior plate and a second exterior plate that is disposed opposite to the first exterior plate and forms an airtight portion between the first exterior plate,
The first exterior plate and the second exterior plate are made of stainless steel,
At least one of the first exterior plate and the second exterior plate is a stainless steel plate having a thickness of 0.1 to 0.6 mm, and the space of the hermetic portion is formed by drawing,
A heat insulating material made of a ceramic porous body or a ceramic fiber heat insulating material having a thermal conductivity of 0.1 W / (m · K) or less is inserted into the hermetic portion,
A fold between the joint formed on the edge of the first exterior plate, the joint formed on the edge of the second exterior plate, and the other joint formed by extending one of the joints. A bent portion and a copper base, an aluminum base, a nickel base or a silver base brazing material interposed between the joint portions and / or between the bent portion and the other joint portion are provided. Insulated container. The heat insulation container according to claim 1, wherein a degree of vacuum of the hermetic portion is 0.1 to 100 Pa. After forming the hermetic space forming part by drawing in at least one of the first exterior plate made of stainless steel and the second exterior plate made of stainless steel having a thickness of 0.1 to 0.6 mm,
A heat insulating material made of a ceramic porous body or a ceramic fiber heat insulating material having a thermal conductivity of 0.1 W / (m · K) or less is accommodated in the airtight portion constituted by the airtight space forming portion,
In advance, a foil-like copper base, aluminum base, nickel base, or silver base brazing material is fixed to the joint provided at the edge of any of the above-mentioned exterior plates by spot welding within a range of 1 to 10 mm from the end. ,
One of the joints formed by extending one of the joints is folded and folded so as to wrap around the bent part sandwiching the other joint,
A method for producing a heat-insulated container, characterized by heat-sealing in a vacuum furnace or an atmosphere furnace capable of preventing oxidation on a stainless steel surface.

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