KR20190026419A - Fire door having structure preventing dew condensation and manufacturing method thereof - Google Patents

Abstract

Disclosed is a fire door having a condensation preventing structure. A fire door having a condensation preventing structure according to the present invention includes a door frame having upper and lower horizontal frames and left and right vertical frames and fixed to the wall, and a door having an inner panel and an outer panel, wherein the space between the inner panel and the outer panel is filled with a heat insulating material, and the door is coupled to the door frame to be openable and closable by a hinge In addition, the opposite end regions of the left and right vertical frames welded to the respective ends of the upper and lower horizontal frames are cut off to form an outer space for blocking the outside air temperature. According to the present invention, it is possible to maximize the interruption of temperature conduction of the outside air by forming the outside air blocking space portion in the end region of the door frame constituting the fire door, and by attaching the auxiliary insulating plate to the inner panel of the door.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a fireproof door having a dew condensation preventive structure,

The present invention relates to a fireproof door having a dew condensation preventing structure and a manufacturing method thereof, and more particularly, to a fireproof door having a dew condensation preventing structure, And a method of manufacturing the same.

Generally, a fire door is used as an entrance door to an outside space such as an apartment or a detached house such as an apartment house, and is made of a metal material such as stainless steel or iron plate, and is made of an outer panel in contact with outside air, Panels are filled with insulation at regular intervals, and then the reinforcing panels are bonded to the upper and lower sides.

In order to install the fire door at the doorway, a door frame made up of upper and lower horizontal frames (aka head, seal) and left and right vertical frames (aka jam) is fixed to the wall and then the fire door is coupled to the door frame. Normally, the fire doors are joined to the door frame using fastening hinges, and the fastening hinges are respectively installed on the upper and lower sides of the fire doors.

Since the outer panel is in contact with the outside air and the door frame is divided into the portion contacting the outside air and the portion not contacting the outside air, the temperature difference is generated between the fire door and the door frame, and when the outside temperature is conducted to the room side in winter Due to the difference between the outside temperature and the room temperature, condensation occurs on the inner panel of the fire door or the inside of the door frame, and the water droplets generated by the condensation cause contaminants such as paint painted walls and wallpaper, There will be a problem.

In order to prevent such condensation, the design standards for condensation prevention in apartment buildings are as follows.

It is designed to be designed to have dew condensation prevention performance below the temperature difference ratio (TDR) according to the condensation prevention performance standard for each main part.

Target site
Temperature difference ratio (TDR) value Area 1 Area 2 Area 3 Generation entrance door
Escape space fire door Door 0.30 0.33 0.38 doorframe 0.22 0.24 0.28

area Area Outside temperature standard Area 1 Gwangju, Dongducheon, Yangpyeong, Chuncheon, Hongcheon, Wonju, Youngwol, Talent, Pyeongchang,
Cheorwon, Taebaek -20 Area 2 Seoul, Incheon Metropolitan City, Sejong City Gyeonggi Province, Chungcheongbuk-do, Chungcheongnam-do, Jeollabuk-do, Gyeongsangbuk-do, Gyeongsangnam-do -15 Area 3 Busan, Daegu, Gwangju, Ulsan, Jeju Island -10

The test method according to the above table is performed by changing the air temperature in the cold room to 20 ° C. and the relative humidity to 40% and changing the air temperature in the low temperature chamber to 5 ° C., 0 ° C., -5 ° C. and -10 ° C. . At this time, the relative humidity in the constant temperature and humidity chamber is raised to 50%, and the sample is observed with the naked eye for 1 hour while keeping it at 50%.

The calculation of the temperature difference ratio (TDR) according to the indoor surface temperature measurement is as follows.

Table 3 shows the calculation of the temperature difference ratio value at the entrance door.

Target site Location
Door

doorframe Door frame corner Diagonal center point of the four corners of the upper left and right, lower left and right
Door
Door center point Crossing of connecting line between opposing door edges Door corner
Hinge type: Vertically and horizontally separated from the edge of the door by 3cm (4 corners of the top left and right and bottom left and right respectively) Hinge method: Hinge method + Point 3cm horizontally from the hinge position at the center of the hinge size (measured at the hinge provided at the top and bottom for two or more hinges)

1, the door frame 2 measures the temperature of the diagonal center point P2 of the four corners of the upper left, right, lower left and right sides of the door frame 1, Calculates the temperature difference ratio (TDR) value by measuring the temperature at a point (P2), which is 3 cm apart from the door edge, vertically and horizontally, respectively.

If the calculated temperature difference ratio (TDR) value deviates from the values shown in Table 1, it is judged that it is below the design standard.

As a conventional technique for satisfying such a dew condensation preventing performance condition, Korean Utility Model Registration No. 20-0344370 (public announcement: March 3, 2004) discloses a dew condensation preventing frame. As shown in FIG. 2, the conventional anti-condensation frame includes an outer frame 110, which surrounds the entrance of the building and is mounted so that the fire door 10 can be pivotally mounted, An inner frame 130 disposed between the outer frame 110 and the outer frame 110 and an outer frame 110 disposed between the outer frame 110 and the inner frame 130, And a blocking member 150 which is fixed while binding the outer frame 110 and the inner frame 130 by a rivet 156 or a piece.

However, such a dew condensation preventing frame is divided into an outer frame, an inner frame, and a blocking member, thereby complicating the structure and deteriorating the manufacturing (assembling) workability, thereby deteriorating productivity. In addition, there has also been a problem that outside air of a cold temperature is transmitted to the inner frame through the blocking member.

Also, since the end portions of the vertical frames to which the end portions of the upper and lower frames, which form the frame frame, are coupled, there is a problem that the above-mentioned dew condensation preventing performance can not be satisfied. That is, the temperature of the cold outside air is conducted inward through each end of the vertical frame to which the upper and lower frames are coupled (the steel plate portion of the vertical frame corresponding to the sectional area of the upper and lower horizontal frames) .

. Korea Registered Utility Model No. 20-0344370 (Notification Date: Mar. 3, 2004)

It is an object of the present invention to improve the connection between the lower horizontal frame and the two vertical frames forming the door frame for the fire door, thereby effectively preventing the heat conduction (the phenomenon that the cold outside air is conducted to the inside) In order to provide a means for the user.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to at least partially solve the problems in the conventional arts. It can be understood.

According to the present invention, there is provided a door frame comprising upper and lower horizontal frames and left and right vertical frames to be fixed to a wall, an inner panel and an outer panel, and a space between the inner panel and the outer panel And a door that is filled with a heat insulating material and is coupled to the door frame so as to be openable and closable by hinges or hinges. The opposite end regions of the left and right vertical frames welded to the respective ends of the upper and lower horizontal frames are And the outside air blocking space is formed so as to cut off the conduction of the outside air temperature, thereby achieving a fireproof door having a dew condensation preventing structure.

The end portions of the left and right vertical frames facing each other may be formed to have a width of 3 to 20 mm at an end of the upper and lower frames to be welded to each other.

The left and right vertical frames and the upper and lower frames may be filled with a heat insulating material.

An auxiliary insulating plate is attached to the inner panel of the door, and can be attached with a magnet attachment structure, a heat insulating adhesive tape attachment structure, a screw attachment structure, or a fitting structure.

The inner space of the auxiliary insulating plate is filled with a heat insulating material, and the upper and lower regions may be filled with different materials and heat insulating materials having different densities.

A reinforcing frame for preventing deformation including warping of the door can be installed between the inner panel and the outer panel of the door, which is composed of an outer reinforcing frame and a central reinforcing frame.

A heat insulating tape having a thickness of 2-7 mm may be attached between the edge portions of the inner panel and the outer panel so as to block warm or cool air so as to separate the respective coupling ends.

An upper portion of the inner panel may be provided with a fire hole for discharging gas in a room fire.

Wherein the upper horizontal frame and the lower horizontal frame comprise an outer horizontal frame positioned on the outdoor side and an inner horizontal frame positioned on the indoor side, And the cold air from the outer horizontal frame is prevented from being transmitted to the inner horizontal frame.

According to the present invention, there is provided a method for manufacturing a fireproof door having a dew condensation preventing structure, comprising the steps of: a) cutting the end regions facing each other of left and right vertical frames, Wherein the outer space is formed to have a size smaller than an area of each end of the upper and lower horizontal frames welded to the respective end regions of the left and right vertical frames, Welding each end portion of the lower horizontal frame to the periphery of the outside air blocking space portion formed at each end region of the left and right vertical frames, respectively, to manufacture the door frame; b) providing reinforcing frames between the inner panel and the outer panel, filling the interior with thermal insulation, and attaching an auxiliary insulation panel to the inner panel; And c) joining the door to the door frame with a hinge or a hinge. The method of manufacturing a fireproof door has a dew condensation preventing structure.

The step b) may further include the step of filling the inner space of the auxiliary thermal insulating plate with a heat insulating material, and filling the upper and lower regions with heat insulating materials having different densities and different materials.

According to the present invention, it is possible to maximize the interruption of temperature conduction of the outside air by forming the outside air blocking space portion in the end region of the door frame constituting the fire door, and by attaching the auxiliary insulating plate to the inner panel of the door, It is possible to provide an effect that can be achieved.

1 is a schematic view for explaining a condensation performance test.
2 is a schematic sectional view showing a conventional anti-condensation frame.
3 is an exploded perspective view showing a door frame of the fire door according to the present invention.
Fig. 4 is a perspective view of the coupled state of the door frame shown in Fig. 3;
5 is an enlarged cross-sectional view of a part of the line AA in Fig.
6 is a front view showing a fire door according to the present invention.
7 is a sectional view taken along line BB of Fig.
8 is a cross-sectional view taken along line CC of Fig.
9 is a partially enlarged cross-sectional view showing another embodiment of the auxiliary insulating plate attachment structure shown in FIG.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, the well-known functions or constructions are not described in order to simplify the gist of the present invention.

FIG. 3 is an exploded perspective view showing a door frame of the fire door according to the present invention, FIG. 4 is an assembled state view of the door frame shown in FIG. 3, FIG. 5 is an enlarged cross- 6 is a front view showing a fire door according to the present invention, and Fig. 7 is a plan sectional view of Fig. And Fig. 8 is a side sectional view of Fig.

3 to 9, a fire door 10 having a dew condensation preventing structure according to the present invention includes upper and lower horizontal frames 22 welded to each other and left and right vertical frames 24, A door frame 20 which is made up of an inner panel 32 and an outer panel 34 and is fixed to a wall (not shown), and a space between the inner panel 32 and the outer panel 34, And a door 30 which is hinged to the door frame 20 or hinged so as to be openable and closable. In particular, the doorframe 20 of the fire door 10 includes opposing end regions 24A of the left and right vertical frames 24 welded and joined to the respective ends 22A of the upper and lower horizontal frames 22, Respectively, to form an outer space 24B for cutting off the outside air temperature.

That is, as shown in Figs. 3 to 5, the shape of the end portion 22A of the upper and lower frames 22 is the same as the shape of the end portions 22A of the upper and lower frames 22 in the opposed end regions 24A of the left and right vertical frames 24, The outer space 24B is formed by cutting out a part of the end region 24A and is formed by cutting an end portion 24A of the upper and lower frames 22 (Or size) of the electrodes 22A and 22A.

This structure is provided so that the end portions 22A of the upper and lower frames 22 are closely welded to each other. In each of the end regions 24A facing each other of the left and right vertical frames 24, a width of 3 to 20 mm The coupling end 24C is formed, and the outside air blocking space portion 24B is formed at the edge of the coupling end 24C. Thus, when welding the end portions 22A of the upper and lower frames 22 to the coupling ends 24C, the welding is performed inside the end portions 22A of the upper and lower frames 22 and at the coupling ends 24C It is possible not only that the welded portion is not exposed to the outside but also firmly supporting the joining end 24C base end 22A.

At this time, if the width of the coupling end 24C is 3 mm or less, the outside air cutoff space 24B is enlarged to improve the conduction cutoff function, but the welding space of the end 22A is insufficient, The cutoff space portion 24B is made smaller and the conduction cutoff function is lowered, but the welding space of the end portion 22A is sufficiently secured. Therefore, the width of the coupling end 24AC is preferably 10 mm.

The interior of the door frame 20 having the above-described structure is filled with a heat insulating material.

5, the upper and lower horizontal frames, in particular, the lower horizontal frame 22, include an outer horizontal frame 22-1 located on the outdoor side and an inner horizontal frame 22-2 located on the indoor side, 2 and upper ends 22-1A and 22-2A of the upper side of the outer horizontal frame 22-1 and the upper horizontal side 22-2 of the inner horizontal frame 22-2 are made of cold air Is interposed with the heat insulating member (22-3) interposed therebetween so as not to be transmitted to the inner horizontal frame (22-2). As described above, the lower horizontal frame 22 is composed of the outer horizontal frame 22-1 and the inner horizontal frame 22-2, and the respective end portions 22-1A and 22-2A are connected to the heat insulating member 22-3. The phenomenon that the cold air on the outdoor side is transmitted to the inner horizontal frame 22-2 through the outer horizontal frame 22-1 can be prevented, and consequently the condensation due to this can be minimized or prevented .

7, the left and right vertical frames 24 are composed of an outer vertical frame 24-1 located on the outdoor side and an inner vertical frame 24-2 located on the indoor side The end portions 24-1A and 24-2A of the outer vertical frame 24-1 and the inner vertical frame 24-2 are arranged such that the cool air from the outer vertical frame 24-1 is transmitted to the inner vertical frame 24- 2 through the heat insulating member 24-3 for blocking the cold air. As described above, the lower vertical frame 22 is composed of the outer vertical frame 22-1 and the inner horizontal frame 22-2, and the respective end portions 22-1A and 22-2A are connected to the heat insulating member 24-3. The phenomenon that the cold air on the outdoor side is transmitted to the inner vertical frame 24-2 through the outer vertical frame 24-1 can be prevented, and consequently, the condensation due to this can be minimized or prevented .

On the other hand, an auxiliary insulating plate 36 is attached to the inner panel 32 of the door 30. The auxiliary heat insulating plate 36 serves as an additional heat insulating material inside the door 30 so as to prevent condensation that may occur on the inner panel 32 side of the door 30, And the inner space S is formed by bending the edge, and the heat insulating material 36A is filled in the inner space S.

The auxiliary insulating plate 36 is attached to the inner panel 32 by an attachment structure by a magnet, an attachment structure by an adhesive tape including a heat insulating tape, an attachment structure by a screw, or a fitting structure. Since the inner panel 32 is made of a metal plate, a magnet is provided on the inner side of the auxiliary heat insulating plate 36 so that the auxiliary heat insulating plate 36 is attached to the inner panel 32 by the magnetic force of the magnet Attached or detached. That is, the magnet attachment structure is also applicable to the door 30 that is installed. Further, the auxiliary heat insulating plate 36 can be attached to the inner panel 32 with screws or the like.

9, the engagement piece 36F is formed at the edge of the auxiliary heat-insulating plate 36 and the coupling hole 32A is formed in the inner panel 32A, so that the auxiliary heat- (Not shown). At this time, a heat insulating tape 36E is attached between the edge of the auxiliary heat insulating plate 36 and the inner panel 32. [

This embodiment will be described on the basis of being attached to the inner panel 32 by the heat insulating tape 36E having a heat insulating function, as shown in Figs. 7 and 8. Fig.

A heat insulating material 36A is filled in the inner space S of the auxiliary heat insulating plate 36 thus configured. Such a heat insulating material 36A is filled with a heat insulating material 36A having different densities and different materials. That is, as shown in FIG. 8, the upper region S1 and the lower region S3 of the inner space S are filled with heat insulating materials 36B and 36C having different materials and different densities, respectively. Here, the heat insulating material 36B filled in the upper region S1 is made of general mineral wool or glass wool, and the heat insulating material 36C filled in the lower region S3 is more heat- Performance is made of better insulation. As described above, the heat insulating material 36C filled in the lower region S3 in which the cold air outside the winter season mostly works and the heat insulating material 36A filled in the upper region S1 are different from each other in density and material, can do. That is, by filling each of the different heat insulating materials 36B and 36C at appropriate positions, it is possible to effectively cut cold air in the winter season, and the cost can also be reduced.

A reinforcing frame 38 is provided between the inner panel 32 and the outer panel 34 of the door 30 to prevent deformation including warping of the door 30. The outer reinforcement frame 38A of the reinforcing frame 38 is disposed on the edge side of the inner panel 32 and the outer panel 34 and the center reinforcement frame 38B is disposed on the upper side outer reinforcement frame 38A and the lower side outer side And the reinforcing frames 38B are vertically connected. The rigidity of the door 30 is improved by the reinforcing frame 38, and various deformation phenomena including warping can be prevented.

As shown in Figs. 7 and 8, between the edge joining ends 32B and 36G of the inner panel 32 and the outer panel 34, a heat insulating tape 39 (thickness: 2 to 7 mm) Are attached so as to be spaced apart from each other so that heat conduction of the respective edge coupling ends 32B and 36G is not performed. That is, the heat insulating tape 39 having the heat insulating function is provided between the edge joining end 32B formed at the edge of the inner panel 32 and the edge joining edge 36G formed at the edge of the outer panel 34, Conduction of cold air including heat can be blocked between the edge coupling ends 32B and 36G of the inner panel 32 and the outer panel 34. [

6, a fire hole 31 may be formed in the upper portion of the inner panel 32 or in the upper portion of the auxiliary heat insulating plate 36 to exhaust the gas in the case of an indoor fire. The fire hole 31 is for discharging gas generated in a fire in the room in advance to prevent diffusion or the like.

A process of manufacturing the fire door 10 having the dew condensation preventing structure according to the present invention constructed as described above will be described.

a) Step

First, an outer air space portion 24B for cutting off the outside air temperature from the outside of the winter season is formed by cutting off the end regions 24A facing each other of the left and right vertical frames 24 forming the left and right of the door frame 20 do. 3, each of the end regions 24A of the left and right vertical frames 24 is cut so as to be close to the cross-sectional shape of the upper and lower horizontal frames 22 to form the outside air blocking space portion 24B .

The outside air blocking space portion 24B is formed in a size smaller than the area of each end portion 22A of the upper and lower horizontal frames 22 welded and joined to the respective end regions 24A of the left and right vertical frames 24, ). At this time, making the size of the outside air blocking space portion 24B smaller than the end portion 22A is intended to form an extra width, i.e., an engaging end 24C, to which the end portion 22A is to be welded. The end portion 22A of the upper and lower horizontal frames 22 can be stably coupled to the end region 24A of the left and right vertical frames 24 by the coupling end 24C.

When the outer space 24B is formed with the coupling end 24C in the above-described process, the respective end portions 22A of the upper and lower horizontal frames 22 are connected to the respective end regions 22A of the left and right vertical frames 24, (24C) formed around the outer space (24B) formed in the outer space (24A), and then welded.

In this process, the door frame 20 formed with the outside air blocking space portion 24B is manufactured, and the interior space of the door frame 20 is filled with the heat insulating material.

b) Step

When the door frame 20 is completed, reinforcing frames 38 are provided between the inner panel 32 and the outer panel 34, and the interior thereof is filled with a heat insulating material. The auxiliary heat insulating plate 36 is attached to manufacture the door 30.

At this time, the heat insulating material 36A is filled in the inner space S of the auxiliary heat insulating plate 36, and the heat insulating material 36B made of mineral wool or glass wool is filled in the upper area S1 of the inner space S, And the lower region S3 is filled with a heat insulating material 36C having better heat insulating performance than the heat insulating material 36B filled in the ceramics or the upper region S1. The heat insulating materials 36C and 36D filled in the upper area S1 and the lower area S3 are filled with materials having different densities from each other.

When the inner panel 32 and the outer panel 34 are engaged with each other, an edge coupling end 32B formed at the edge of the inner panel 32 and an edge coupling edge 36G formed at the edge of the outer panel 34 A heat insulating tape 39 having a heat insulating function is provided to prevent conduction of cold air including heat between the edge joining ends 32B and 36G of the inner panel 32 and the outer panel 34, (32) and the outer panel (34).

c) Step

When the manufacture of the door 30 is completed by the above-described process, the door 30 is coupled to the door frame 20 with a hinge or a hinge.

The fire door 10 having the dew condensation preventing structure can be manufactured by the process described above.

The fire door 10 having the above-described condensation preventing structure has the outer air interception space portion 24A in the end region 24A of the left and right vertical frames 24 to which the ends of the upper and lower horizontal frames 22 are welded 24B are formed so as to be blocked by the cold air outside air blocking space portion 24B of the outside air, it is possible to maximize the blocking of the cold air from the outside air.

1, since the temperature of the lower corner areas P1 and P2 of the fire door 10 is measured in the dew condensation preventing performance test of the fire door 10, The outer space 24B is formed in the corresponding end region 24A to prevent the cold air from being conducted. Thus, the temperature difference ratio TDR according to the indoor surface temperature measurement can be satisfied. That is, since the cold air of the outside air transmitted from the outside of the end region 24A does not pass through the outside air blocking space portion 24B (the space where the heat insulating material is filled), the cold blocking can be efficiently performed.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It is obvious to those who have. Accordingly, it should be understood that such modifications or alterations should not be understood individually from the technical spirit and viewpoint of the present invention, and that modified embodiments fall within the scope of the claims of the present invention.

10: fire door 20: door frame
22: upper and lower horizontal frame 22A: end
24: left and right vertical frame 24A: end area
24B: outside air blocking space part 24C: connecting end
30: door 32: inner panel
34: outer panel 36: auxiliary insulating plate
36A, 36B, 36C: Insulation material 38: Reinforcing frame
36E, 39: Insulating pad S: Space
S1: Upper space S3: Lower space

Claims (9)

The door frame is composed of upper and lower horizontal frames and left and right vertical frames and is fixed to the wall. The door frame is composed of an inner panel and an outer panel. The space between the inner panel and the outer panel is filled with a heat insulating material. And a door that is coupled to the hinge so as to be openable and closable,
Wherein an outer air blocking space is formed to cut off the opposite end regions of the left and right vertical frames welded to the respective ends of the upper and lower horizontal frames,
Fireproof doors with anti-condensation structure. The method according to claim 1,
In each of the opposite end regions of the left and right vertical frames,
Wherein an upper end of the upper frame and a lower end of the lower frame are welded to each other to form a welded end having a width of 3 to 20 mm.
Fireproof doors with anti-condensation structure. 3. The method of claim 2,
Wherein the left and right vertical frames and the upper and lower frames are filled with a heat insulating material.
Fireproof doors with anti-condensation structure. 3. The method of claim 2,
Characterized in that an auxiliary heat insulating plate is attached to the inner panel of the door, wherein the heat insulating adhesive is adhered to the inner panel of the door by an adhesive structure comprising a magnet, an adhesive tape comprising a heat insulating adhesive tape,
Fireproof doors with anti-condensation structure. 5. The method of claim 4,
A heat insulating material is filled in the inner space of the auxiliary heat insulating plate,
Characterized in that an upper region and a lower region of the inner space are filled with heat insulating materials having different materials and different densities, respectively,
Fireproof doors with anti-condensation structure. 6. The method of claim 5,
Wherein a heat insulating pad having a thickness of 2 to 7 mm is attached between the edge portions of the inner panel and the outer panel so as to block warm or cool air,
Fireproof doors with anti-condensation structure. The method according to claim 1,
The upper, lower,
An outer horizontal frame located on the outdoor side and an inner horizontal frame located on the indoor side,
Wherein each end of the upper side of the outer horizontal frame and the upper side of the inner horizontal frame is coupled with a heat insulating member interposed therebetween to prevent cold air from the outer horizontal frame from being transmitted to the inner horizontal frame.
Fireproof doors with anti-condensation structure. A method for manufacturing a fire door having a dew condensation preventing structure,
a) forming an outer space interception space portion for cutting out the opposite end regions of the left and right vertical frames constituting the left and right sides of the door frame so as to block the conduction of the outside air temperature, And the upper and lower horizontal frames are formed to have a size smaller than an area of each of the end portions of the upper and lower horizontal frames, Welded to each other to manufacture a door frame;
b) providing reinforcing frames between the inner panel and the outer panel, filling the interior with thermal insulation, and attaching an auxiliary insulation panel to the inner panel; And
c) coupling said door to said door frame with a hinge or hinge.
A method for manufacturing a fireproof door having a dew condensation preventing structure. 9. The method of claim 8,
The step b)
A heat insulating material is filled in the inner space of the auxiliary heat insulating plate,
The method of claim 1, further comprising filling the upper and lower regions of the inner space with heat-insulating materials of different materials and different densities.
A method for manufacturing a fireproof door having a dew condensation preventing structure.

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