JP4377654B2 - Refractory container - Google Patents

Description

  The present invention relates to a refractory container that protects stored items from an external high temperature.

  Conventionally, a fireproof container such as a safe keeps heat conduction to the inside low by a wall of a porous body such as foamed concrete having low thermal conductivity. Also known is a configuration in which water sealed between the foamed concrete walls is built in, the water is leached into the foamed concrete by heat, and the heat flowing through is absorbed. Furthermore, Patent Document 1 discloses a structure in which a substance that reacts with water to produce a digestive agent is embedded between foamed concrete walls together with sealed water.

  It is also known that the wall of the refractory container has a multi-layer structure made of a plurality of types of refractory materials. The inside of the wall is provided with a wall enclosing a salt that releases crystal water at a certain temperature or higher, and the salt is crystallized Patent Document 2 discloses a structure in which heat is hardly transmitted to the inside by absorbing heat when water is released and melted.

  In a structure containing water sealed in a wall such as foamed concrete, water absorbs heat, but also functions as a medium for transferring heat. For this reason, the thermal conductivity of the foamed concrete from which water has leached increases, and the amount of heat entering from the outside increases. Thus, the water leached into the foamed concrete is exposed to a higher temperature and evaporates one after another. In order to maintain the fire resistance for a long time, it is necessary to incorporate more water.

Further, the endotherm when the salt is melted by releasing crystal water is smaller than the heat of vaporization of water, and is effective only when the amount of heat flowing through is small. In other words, it protects the interior from residual heat after the external fire has been extinguished, and cannot cope with a large temperature gradient.
Japanese Utility Model Publication No. 6-54883 No. 6-40867

  As described above, the conventional technique only slightly delays the temperature rise inside the container when the heat insulation performance of the outer wall of the refractory container reaches the limit. In other words, the performance of the refractory container largely depends on the heat insulation performance of the outer wall such as foamed concrete, and in order to obtain high fire resistance, it is necessary to increase the thickness of the outer wall.

  This invention makes it a subject to provide the fireproof container which has high fireproof performance, without thickening an outer wall.

The refractory container according to the present invention is installed in a vacuum double container in which a space between the outer wall and the inner wall is evacuated to form a vacuum heat insulating layer so as to have an intermediate space between the vacuum double container. An inner container, a gas flow path that communicates the intermediate space and the outside of the vacuum double container, a heat insulating lid that seals the intermediate space and the inner container, and the intermediate space, Water is sealed inside, the sealing property is lost at 60 ° C. to 130 ° C., and the water sealed inside is leaked, and the outer wall of the heat-resistant porous body is provided outside the vacuum double container. And the outer wall of the porous body has a window that can be partially removed .

According to this configuration, the double container can substantially prevent the heat from entering the inside, but still a small amount of heat that has flowed through the double container enters the intermediate space. The container enclosing the water accommodated in the intermediate space melts or loses its sealing ability when the temperature exceeds a certain temperature due to the heat entering the intermediate space, and leaks the enclosed water. The leaked water evaporates and takes heat of vaporization, and is discharged outside from the gas flow path. Thus, by releasing the heat that has flowed through the vacuum double container to the outside of the refractory container, it is possible to prevent the heat from entering the storage space and continuously prevent the temperature of the storage space from rising.

Further, the outer wall of the porous body alleviates local and rapid temperature rise of the vacuum double container, and prevents the metal structure of the vacuum double container from being destroyed by shocking heat load. . Thereby, the temperature rise of the storage space in an internal container can be prevented reliably. Moreover, the heat insulation performance of the vacuum double container can be regularly checked by removing the window and heating the outer wall of the vacuum double container.

Moreover, the fireproof container by this invention WHEREIN: The bag which enclosed water with the film may be sufficient as the container which enclosed the said water.

  According to the present invention, it is possible to provide a fireproof container that is small and excellent in fireproof performance.

(First embodiment)
FIG. 1 shows a refractory container 1 according to a first embodiment of the present invention. In the refractory container 1, an internal container 4 is provided inside a metal vacuum double container 2 having a vacuum heat insulating layer 3, and the inside of the internal container 4 is a storage space 5 in which stored items are stored. The inner container 4 has a gap between the vacuum double container 2 and the gap is sealed by a flange portion 4 a of the inner container 4 to form an intermediate space 6. The vacuum double container 2 is provided with a nozzle 7, and the intermediate space 6 communicates with the outside of the vacuum double container 2 through the nozzle 7. Further, a ceramic board lid 8 for sealing the openings of the vacuum double container 2 and the inner container 4 is provided, and a ceramic board bottom lid 9 is provided so as to cover the nozzle 7. The intermediate space 6 stores a large number of bags 10 in which water is sealed with a film obtained by laminating polyethylene on aluminum foil.

  The vacuum heat insulating layer 3 of the vacuum double container 2 constituting the refractory container 1 has high heat insulating performance even if it is thin because there is no heat conduction or convection medium. With this feature, the vacuum heat insulating layer 3 can suppress the intrusion of heat into the intermediate space 6 even when the refractory container 1 is placed at a high temperature. On the other hand, since the heat outside the refractory container 1 tends to enter the storage space 5 from the lid 8, the lid 8 also needs to have heat insulation performance. Although it is possible to apply a vacuum heat insulation panel to the lid 8 as well, in this embodiment, the lid 8 is a ceramic board having a sufficient thickness. Further, the bottom lid 9 prevents heat from being brought into the interior due to the movement of air from the outside of the vacuum double container 2 into the intermediate space 6 through the nozzle 7.

  As described above, the refractory container 1 has a structure that effectively prevents the intrusion of heat into the inside. However, it is still difficult to completely block the intrusion of heat, and the heat flows through the inside slightly. When heat enters the intermediate space 6 in this way, the temperature of the bag 10 and the enclosed water stored in the intermediate space 6 rises. The bag 10 is formed by heat-welding polyethylene, but the polyethylene melts at a temperature close to 100 ° C., and the water enclosed in the bag 10 leaks out. At this time, it is preferable that the enclosed water has viscosity by adding a thickener or the like so that it does not easily flow down to the lower part of the internal space. Furthermore, the leaked water evaporates and takes heat of vaporization. At this time, since the intermediate space 6 communicates with the outside of the vacuum double container 2 by the nozzle 7, the generated water vapor is ejected from the nozzle 7 to the outside by the pressure. The bottom lid 9 of the porous body prevents air outside the refractory container 1 from entering the intermediate space 6, but does not prevent the passage of water vapor with pressure, and is generated in the internal space. The steam is discharged to the outside of the refractory container 1.

  As described above, the water leaked from the bag 10 is sealed in the intermediate space 6 while the heat that has entered the refractory container 1 is discharged to the outside as water vapor. For this reason, the leaked water is not leached out of the vacuum heat insulating layer 3 and exposed to a high temperature and consumed more than necessary, and the temperature rise of the storage space 5 can be prevented continuously.

(Second Embodiment)
FIG. 2 shows a refractory container 1a according to a second embodiment of the present invention. The refractory container 1a has a vertical structure in which a stored item is placed on the center of the pedestal 8 using the ceramic board lid 8 as a pedestal. The intermediate lid 11 can seal the intermediate space 6 and fix the inner container 4 to the vacuum double container 2. This refractory container 1a is formed by placing a stored item on a base 8 and then simultaneously covering the vacuum double container 2 and the inner container 4 that have been assembled by the intermediate lid 11 at the same time. 12 is covered. A filling 13 is packed in the nozzle 7 of the refractory container 1a. The intermediate space 6 is filled with a hydrated material 14.

  The vacuum double container 2 has high heat insulating performance due to the vacuum heat insulating layer 3. However, since the vacuum double container 2 is made of metal, it may be deformed or damaged when exposed to a local or rapid temperature increase. For this reason, the outer wall 12 made of a ceramic board is provided as a buffer material to prevent excessive uneven distribution or sudden fluctuation of the heat load from the outside of the refractory container 1a from being directly applied to the vacuum double container 2. That is, in the refractory container 1a, the heat insulating performance required for the outer wall 12 is not large, and a thin outer wall 12 is sufficient.

  When the refractory container 1a is placed at a high temperature, the outer wall 12 softens the local and rapid temperature rise to an extent that the vacuum double container 2 can tolerate, and the vacuum heat insulating layer 3 of the vacuum double container 2 has the intermediate space 6 Suppresses heat intrusion. Still, when heat is transferred to the inside of the vacuum double container 2, the temperature of the hydrated material 14 filled in the intermediate space 6 rises. The hydrate 14 used in this embodiment is a trehalose hydrate crystal (trehalose dihydrate). Trehalose hydrous crystals are carbohydrates containing about 10% of crystal water, and vaporize and release crystal water at 100 to 130 ° C. In addition, at room temperature, the water containing trehalose can hold water of crystallization semipermanently.

  When heat from the outside further enters the intermediate space 6, the crystal water released from the water-containing material 14 evaporates by taking the heat of vaporization, and is ejected from the nozzle 7 to the outside of the vacuum double container 2 as water vapor. The filling 13 of the nozzle 7 is a heat insulating material such as ceramic wool, and prevents heat outside the vacuum double container 2 from being transmitted to the intermediate space 6 due to air convection. However, the pressure rises due to the generation of water vapor. On the other hand, it does not prevent the passage of gas. Moreover, the ceramic board of the outer wall 12 is also a porous body, and similarly prevents convection of air but allows water vapor having pressure to pass therethrough and release it to the outside of the refractory container 1a.

  Thus, the heat that has flowed through the outer wall 12 and the vacuum heat insulating layer 3 is released from the outer wall 12 through the nozzle 7 as heat of vaporization of water vapor. In this process, the crystal water of the hydrated substance is sealed in the intermediate space 6 and does not leach into the vacuum heat insulating layer 3 or the outer wall 12 to deteriorate the heat insulating performance. Therefore, the crystal water of the hydrous material 14 can flow away through the vacuum heat insulating layer and take away only the heat that has entered the intermediate space 6, and it can continue to move to a place where the temperature is high and is not consumed more than necessary. Therefore, the temperature rise of the storage space 5 can be prevented. Moreover, it is also possible to give more fire resistance by applying a combination of conventional techniques such as including a salt containing crystal water in the outer wall 12.

(Third embodiment)
FIG. 3 shows a refractory container 1b according to a third embodiment of the present invention. The refractory container 1b is a horizontal type as in the first embodiment, has a ceramic board outer wall 12 and an intermediate lid 11 as in the second embodiment, and encloses the hydrated matter 14 in the intermediate space 6. However, the refractory container 1 b does not have the nozzle 7 that communicates the intermediate space 6 and the outside of the vacuum double container 2. Instead, a hole 15 is provided in the upper part of the intermediate lid 11. Further, the inner container 4 is provided with an inner lid 16, and the outer wall 12 is provided with a window 17 that can be partially removed.

  In the refractory container 1b, the heat that has flowed through the outer wall 12 and the vacuum heat insulating layer 3 and entered the intermediate space 6 evaporates the crystal water that has been released by melting the hydrated material. The generated water vapor is ejected to the outside as the vaporization heat of the water vapor through the ceramic board lid 8 from the hole 15 provided at a high position of the intermediate lid 11 so that the hydrated substance 14 does not leak out. At this time, an inner lid 16 is provided in the inner container 4 in order to prevent water vapor from entering the storage space 5. The refractory container 1b of the present embodiment may be structured such that the intermediate container 11 is not provided and the inner container 4 having the flange portion 4a is used similarly to the first embodiment, and the flange portion 4a is provided with a hole.

  The window 17 is for checking the performance of the vacuum double container 2. If the vacuum degree of the vacuum heat insulation layer 3 falls, the heat insulation performance will fall. This is called “vacuum blur”, and it is preferable to periodically check that the vacuum double container 2 is not in such a state. Therefore, the outer wall of the vacuum double container 2 is heated from the outside by removing the window 17 and applying a heat ray of a halogen lamp to the outer wall of the vacuum double container 2 to increase the temperature of the inner wall of the vacuum double container 2. Insulation performance can be checked by measuring with a thermocouple installed at the time of manufacture.

  As described above, the present invention has realized an effective heat insulating layer of a heat-resistant container and a structure for effectively discharging the heat that has flowed through the heat insulating layer out of the system.

Sectional drawing of the fireproof container which is 1st Embodiment of this invention. Sectional drawing of the fireproof container which is 2nd Embodiment of this invention. Sectional drawing of the fireproof container which is 3rd Embodiment of this invention.

Explanation of symbols

1, 1a, 1b Refractory container 2 Vacuum double container 4 Inner container 6 Intermediate space 7 Nozzle 8 Lid (pedestal)
10 bags 12 outer walls 14 water content 15 holes

Claims (2)

An internal container installed so as to have an intermediate space between the vacuum double container and the vacuum double container in which a space between the outer wall and the inner wall is evacuated to form a vacuum heat insulating layer;
A gas flow path communicating between the intermediate space and the outside of the vacuum double container;
A heat insulating lid for sealing the intermediate space and the inner container;
A container that is contained in the intermediate space, encloses water therein, loses its sealing property at 60 ° C. to 130 ° C., and leaks out the encapsulated water ;
An outer wall of a porous body having heat resistance on the outside of the vacuum double container;
The outer wall of the porous body has a window that can be partially removed . The fireproof container according to claim 1 , wherein the container enclosing the water is a bag enclosing water with a film.

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