JPH11301736A - Magnesia storage - Google Patents

Abstract

(57) [Summary] [Problem] To provide a magnesia storage that can be stored well without causing deterioration or cracking or cracking of the magnesia molded article during storage. The interior of the refrigerator was lined with urethane foam insulation to improve the heat insulation effect with the outside air. Air conditioner 2 in this cabinet
Was installed on the ceiling of the cabinet 1, and the dehumidifier 3 was installed on the bottom of the cabinet 1. Further, a ventilation duct 6 having a circulation fan 7 having an inlet side above the cabinet 1 and an exhaust side below the cabinet 1 was provided. Since the air in the cabinet is agitated by the circulation fan 7, the environment can be made constant in any place, and therefore, the parts in any place can be stored with good quality.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnesia storage, and more particularly to a magnesia storage that can be stored well without deterioration or cracking or cracking of the magnesia molded article during storage.

[0002]

2. Description of the Related Art Conventionally, a so-called setter made of a magnesia sintered body in the shape of a casing, a plate, a cylindrical crucible, or the like is made of electronic ceramic materials such as capacitors, piezo elements, ferrites, varistors, and thermistors. It is used as a firing jig. It is formed by a forming step in a step before reaching the sintered body. For example, in general, the molding process includes a method of pressing dry granulated powder and a molding method such as slip casting. If this molded body is left in a room for a certain period of time or more, it reacts with the moisture in the air (hydration reaction) due to the chemical properties of magnesia, and the magnesia molded body becomes part or most of magnesium hydroxide. . If such a change in the substance occurs, the magnesia molded body is broken or fine cracks are generated, and the magnesia molded product does not become a product even when fired. Therefore, often small cracks that cannot be found with the naked eye, or
If there was a microstructural defect, overlooked firing did not yield a good quality sintered body at all.

[0003]

As described above, when the magnesia molded body as described above is stored in a general air-conditioned room, it cannot be stored even in a humid season. Originally, if the molded body can be immediately transferred to the firing step, the above-mentioned problem does not occur, but generally,
A method in which a compact is formed and stored to some extent and then fired collectively is employed for economic efficiency.

[0004] The reason for this is that it is necessary to operate the molding equipment and firing equipment efficiently, but depending on the case, the capacity of the firing equipment is about 3 to 6 times the amount that can be molded in one day. Since the sintering time takes 3 to 6 days, the molded body is at least 3 to 6 days before the next sintering step.
Six days must be stored in some way. Occasionally, storage periods can be over one month for process reasons. In the conventional methods, the storage limit of the molded body was about one to three days even in winter when the humidity is low. In addition, since people can enter and exit the air-conditioned room freely, the air is replaced with the outside when entering and exiting, and the amount of saturated steam in the air-conditioned room increases. In addition, the work was sometimes performed in an air-conditioned room, and the humidity could not be extremely reduced in terms of occupational health. Thus, there is naturally a limit in favorably storing a magnesia molded body in a general air-conditioning room.

[0005]

The inventors of the present invention have conducted various studies on the above-mentioned problems, and as a result, have made it possible to reduce the change in the storage environment, maintain the environment at all times, and improve the magnesia molded body. The present invention has been made based on this finding by proposing a storage that can be stored. Therefore, an object to be solved by the present invention is to provide a magnesia storage that can be favorably stored without deterioration or cracking or cracking of the magnesia molded body during storage.

[0006]

The above object of the present invention is achieved by the following inventions.

(1) An interior of a cabinet having an air conditioner on the ceiling, a dehumidifier on the bottom and a heat insulating material on the inner surface is divided by a shelf plate, and a hygrometer is provided on an upper portion of a side wall of the cabinet. A magnesia storage, characterized in that the magnesia storage is provided with a ventilation duct on the facing wall of the side wall from the upper side to the lower side and a circulation fan at a lower end of the ventilation dust. (2) The magnesia storage according to the item (1), wherein the shelf has a large number of ventilation holes.

[0008] The magnesia storage of the present invention has an air conditioner on the ceiling, a dehumidifier on the bottom and a heat insulating material on the inner surface, and the inside of the cabinet is divided by a shelf plate.
A hygrometer is provided on the upper part of the side wall of the cabinet, and a ventilation duct is provided on the opposite wall of the side wall from the upper side to the lower side, and a circulation fan is provided on a lower end of the ventilation dust, so that a storage fan can be stored. The magnesia molded body can be stored well without altering, cracking or cracking. At this time, since the shelf plate has a large number of ventilation holes, the atmosphere between the top and bottom is uniform, and there is no variation in the molded body placed anywhere in the storage, and the state of the molded body with uniform quality is good. Saved in.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in more detail, but the present invention is not limited only to these embodiments.

FIG. 1 is a schematic perspective view of a magnesia storage according to the present invention having a cutout. In the present invention, a storage for exclusively storing the magnesia molded body was manufactured. For the production of this storage, a commercially available steel prefabricated simple warehouse (hereinafter referred to as a cabinet) was used. The dimensions of the magnesia storage are 1500 mm wide, 700 mm deep, 2 high
The interior of the cabinet was lined with a urethane foam heat insulating material having a thickness of 000 mm and a thickness of 25 mm to improve the heat insulating effect against the outside air and prevent the dew condensation on the inner wall of the cabinet.

In FIG. 1, an air conditioner 2 having a cooling capacity of 3200 kcal and a dehumidifying capacity of 5.6 l / D are provided in a cabinet.
An AY dehumidifier 3 was provided. That is, the air conditioner 2 is installed on the ceiling of the cabinet 1 and the dehumidifier 3 is
At the bottom or floor. Further, a ventilation duct 6 having a circulation fan 7 having an inlet side at the upper part of the cabinet 1 and an exhaust side at the lower part of the cabinet 1 is provided so as to prevent partial unevenness in temperature and humidity in the cabinet 1. The air in the cabinet is sucked from the upper part by the circulation fan 7 as shown by the arrow, and flows into the lower part of the cabinet 1 through the fan 7 and the duct 6.

In the present invention, the air flows from the upper part to the lower part because the cool air from the air conditioner 2 has a large specific gravity, and therefore descends to the lower part of the cabinet 1. On the other hand, the hot air in the upper part is forcibly circulated to the lower part by the circulating fan 7 and collides with the cold air descending from the air conditioner 2 to sufficiently mix the air in the cabinet 1. As a result, the air in the cabinet 1 is agitated, so that any place can have a constant environment. Therefore, parts of any place can be stored with good quality. Further, in the present invention, the favorable environment of the magnesia storage is preferably to adjust the temperature of the room to 22 ° C. ± 5 ° C. in summer and to 18 ° C. ± 5 ° C. in winter. Good. Further, the relative humidity in the room is preferably maintained at 45 ± 5% throughout the year.

On the other hand, if the flow of air in the ventilation duct 6 is reversed, the air flow is the same as natural convection. A temperature difference and a humidity difference occur between the upper portion and the lower portion, and a favorable environment cannot be obtained. Furthermore, in order to make the environment in the cabinet 1 more uniform, a plurality of shelves 4a, 4b, 4
c is provided. The shelf 4 may also be formed of a strong mesh. When the shelf plate 4 is a plate-like body, a large number of holes 8 can be provided in the plate, and the holes 8
It is preferable to provide them uniformly. For example, a large number of holes were drilled at a pitch of about 80 mm with a diameter of 52 mm to improve air permeability.

[0014]

According to the present invention, by forcibly circulating the air flow in the ventilation duct 6 from the upper part to the lower part, a uniform and constant environment can be provided at any place in the cabinet. Further, by providing a large number of holes 8 in the shelf plate 4, the air circulation is further improved and a constant environment is provided.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment using the magnesia storage of the present invention will be described below in more detail.

Example 1 Electrofused magnesia was pulverized to a fine powder having an average particle diameter of about 1.5 μm, and the resulting powder was spray-dried to form a CIP. Size is 1
From July to August, in a cabinet in which 10 crucibles each having a size of 30 mm × 130 mm × 80 mmH and 10 cylindrical crucibles having a diameter of 160 mm and a height of 250 mmH were maintained at a temperature of 20 ° C. and a humidity of 45%. Stored for 2 months.
When this molded body was fired at a maximum temperature of 1650 ° C., the yield rate was 100%. As a comparative example, all of the two compacts stored for 24 hours in the same season in an air-conditioned room (floor area: 24 m ² , height: 3.5 m, heat capacity of air conditioner: 5000 kcal) set at 26 ° C. Fine cracks occurred on the surface of the molded product, and a good product could not be obtained.

As Comparative Example 2, 130 mm × 1 was placed in the same room from December to January in the same manner as Comparative Example 1.
10mm φ, 160m with 30mm x 80mH
Among the five cylindrical crucibles of mx250 mmH stored for one week, those with fine cracks on the surface were 130x130x80H, 8 out of 10 and φ1
60 × 250H was four out of five. When no cracks were fired at a maximum temperature of 1650 ° C., any of the cracks was cracked, and good products could not be obtained.

Example 2 The same compact as in Example 1 was stored in the storage in January at a relatively low humidity of 128 mm.
A 128 mm × 80 mmH bowl-shaped formed body was stored for one month. The molded body was fired at a maximum temperature of 1650 ° C.
All products became good products. In the same experiment, a shelf with no holes was used, and the experiment was performed using five stages of shelves.
Fine cracks occurred in the molded product. As Comparative Example 3, the dehumidifier 3 of the storage 1 was stopped, and only the air conditioner 2 and the circulation fan 7 were operated.
When the box-shaped molded article of × 128 mm × 80 mmH was stored for 3 days, cracks occurred on the surface of the molded article.

Further, in Comparative Example 4, the same compact 9 as in Comparative Example 3 was operated by operating the dehumidifier 2 and the circulation fan 7, and
Stopped. When stored in the storage 1 at the same time for 3 days, cracks occurred on the surface of the molded body as in Comparative Example 3. As can be seen from these comparative examples, the magnesia storage of the present invention provides a synergistic effect between the air conditioner and the dehumidifier, and their functions, so that the circulation fan further enhances this function. By doing so, it contributes to prevention of hydration of the magnesia molded body. Therefore, even if one of them is missing, the intended effect cannot be exhibited. In addition, by drilling several holes in the shelf, uniform quality can be maintained regardless of the parts in the storage room. A compact can be obtained.

[0020]

The magnesia storage of the present invention has an air conditioner on the ceiling, a dehumidifier on the bottom and a heat insulating material on the inner surface, and the inside of the cabinet is divided by a shelf plate. The magnesia molded body during storage is provided with a hygrometer at the top, a ventilation duct on the opposite wall of the side wall communicating from above to below, and a circulation fan at the lower end of the ventilation dust. It can be stored satisfactorily without deterioration, cracking or cracking. Further, in the present invention, the shelf plate has a large number of ventilation holes, so that the atmosphere between the upper and lower sides becomes uniform, so that there is no variation even in a molded body placed at any place inside the storage, and a molded body with good uniform quality is obtained. Saved in state.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a magnesia storage of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cabinet 2 Air conditioner 3 Dehumidifier 4, 4a, 4b, 4c Shelf 5 Hygrometer 6 Ventilation duct 7 Circulation fan 8 Hole 9 Magnesia molded object

Claims (2)

[Claims] 1. A cabinet having an air conditioner on the ceiling, a dehumidifier on the bottom and a heat insulating material on the inner surface is divided by a shelf plate, and a hygrometer is provided on the upper side wall of the cabinet. A magnesia storage, characterized in that a ventilation duct communicating from above to below is provided on a facing wall of the side wall, and a circulation fan is provided at a lower end of the ventilation dust. 2. The magnesia storage according to claim 1, wherein the shelf has a plurality of ventilation holes.