KR20140082562A - Fireproof Container Improved in Circulation of Heat and Safety of Use - Google Patents

Abstract

The present invention relates to a refractory container improved in thermal circulation and safety, and a refractory container improved in thermal circulation and safety according to an embodiment of the present invention is a refractory container loaded in an industrial furnace for heat treatment of a powder or an article, And a convex portion is formed on the outer wall of the refractory container.
According to another aspect of the present invention, there is provided a refractory vessel for heat treatment, the refractory vessel having improved thermal circulation and safety, wherein the refractory vessel is a hexahedron having a space or spaces with a predetermined volume for accommodating powder or articles to be heat- And a protruding block having a predetermined shape is formed on at least one of the outer front surface, the rear surface, the left surface, and the right surface of the refractory container.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fireproof container having improved heat circulation and safety,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refractory container used for a high-temperature heat treatment such as powder or parts, and more particularly to a refractory container used for a high- And the gap can be easily maintained, so that circulation of the heat and the gas during the heat treatment is uniform and smooth.

It can be used in high-tech electronic industries such as ferrite, condenser, varistor, PTC, MLCC and other electronic parts, firing of metal or ceramic powder products, heat treatment of metal and ceramic powder, Kiln), RHK (Roller Hearth Kiln), tunnel type continuous furnace, pusher type continuous furnace, vacuum sintering furnace, elevator type furnace are used.

In the above-described heat treatment furnace, a refractory container is used for carrying out a heat treatment uniformly and safely at a high temperature by containing an object such as a part or powder. These refractory vessels are often used in rectangular refractory vessels, but circular refractory vessels are also used. In addition to the name 'refractory vessels', they are also referred to as crucibles, box saggers, trays, crucibles, and setters.

5, the furnace itself has a length of about 20 to 100 m and is composed of a preheating furnace 170, a burning furnace 180, and a cooling furnace 190 from the inlet of the furnace. In the case of the continuous furnace RHK, Long roll-shaped rollers 160 made of alumina or silicon carbide are arranged so that the refractory vessels can be continuously moved in one direction with the RHK.

As the roller 160 rotates at a constant speed, the refractory container is moved in one direction inside the furnace, and the material to be treated 130 is heated while passing through the heating band 170, Treated and cooled through the cooler (190).

At this time, as shown in FIG. 7, the refractory vessels are continuously moved from the first row to the fourth column on the roller 160, and the interval between the refractory vessels is adjusted in consideration of heat circulation and the like.

On the other hand, in the case of a typical non-continuous loop line type furnace, the furnace body 150 and the heat treatment furnace main body 140 are structured as shown in FIG.

The refractory container containing the plastic 130 is loaded on the carriage 150 and is pushed into the furnace body 140. The temperature of the furnace body 140 is then raised to a high temperature and then the furnace body 140 is cooled And then the truck 150 is taken out.

At this time, the refractory vessels are arranged at regular intervals on the bogie 150 for thermal circulation and uniform heat treatment, and the refractory vessels are stacked thereon at various stages.

In addition to the above-mentioned RHK furnace, the refractory vessel is similarly used in other heat treatment furnaces such as a tunnel continuous furnace, a pusher type continuous furnace, a vacuum sinter furnace, and an elevator furnace.

On the other hand, refractory vessels are usually manufactured through the following processes.

In this case, ceramic raw materials such as Alumina, Silica, Magnesia, Mullite, Kaolin, Clay, Talc, Spinnel, Chamotte and Cordierite are used as main raw materials and these raw materials are mainly composed of Al 2 O 3, SiO 2 and MgO.

These raw materials are pulverized into powders of several micron to several millimeters in size.

Processes for manufacturing refractory containers include a press method and an injection molding method.

At this time, each of the raw materials in the form of powder is weighed according to the mixing ratio according to the characteristics (usage, use temperature, product shape, strength, etc.) required for the refractory container to be manufactured, and then the mixture is uniformly mixed using a mixer For example, polyvinyl alcohol, carboxymethylcellulose, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylpyrrolidone, polyvinylpyrrolidone, A binder such as methylcellulose, a lubricant, a releasing agent and the like are added.

In this manner, a raw material mixture to which water and an additive are added is prepared, a mold capable of forming a rectangular or circular container shape is prepared, and mounted on a press capable of applying a high pressure such as a hydraulic press, a friction press, The raw material mixture to which the moisture and the additive is added is injected into the mold and is pressed by a press to form a refractory container such as a quadrangle or a circle.

The molded article thus molded is put into a dryer and dried at a temperature of 50 캜 or higher for about 12 hours to make the water content in the molded article to be within 1%.

The dried shaped body is calcined in a kiln at a temperature of 1200 to 1700 ° C. for 2 hours or more to complete a refractory vessel having a certain strength through sintering and thermochemical reaction of the raw powder.

On the other hand, in the injection molding method, each raw material in powder form is weighed according to the mixing ratio according to the characteristics (usage, use temperature, product shape, strength, etc.) required for a refractory container to be manufactured, And 10 to 20% of water, a dispersant, a binder and the like are added, and the mixture is stirred with a stirrer to obtain a viscous liquid.

When the viscous liquid thus prepared is injected into a mold of a gypsum mold having a shape of a refractory container, the gypsum absorbs moisture from the viscous liquid, and after a certain time, the viscous liquid becomes a solid molded article having the shape of the refractory container.

The molded article thus molded is put into a dryer and dried at a temperature of 50 캜 or higher for about 24 hours so that the moisture content in the molded article is within 1%.

The dried body is baked in a kiln at a temperature of 1200 to 1700 ° C. for 2 hours or more to complete a refractory container having a certain strength through sintering and thermochemical reaction of the raw powder.

Refractory vessels have been used for various types of heat treatment industrial furnaces in which powder or certain types of articles are packed and subjected to high temperature heat treatment. However, various problems arise due to structural characteristics of the heat treatment furnace and problems in use during use.

That is, in the case of the continuous furnace RHK, the length of the furnace itself is shortened from 20 m to 100 m, and the refractory container is moved by the rotation of the roller in the furnace.

In this case, it is important that the movement of the refractory container moved by the rotation of the rollers of the entire furnace is linear, and the level of the roller is accurately adjusted for linear movement. However, The straightness may be distorted.

Particularly, as shown in FIG. 6 (b), when the refractory vessels are arranged at the entrance of the furnace for the thermocycling, the proceeding direction and the proceeding speed are slightly increased As shown in FIG. 7 (b), as shown in FIG. 7 (b), the intervals are different from each other, the uniformity of the temperature is not good and the distances between the refractory containers are deteriorated and the rectilinearity of the refractory container is deteriorated due to interference between the refractory containers. There is a case where the inside of the furnace is damaged due to a collision with the wall surface, or the inside of the furnace is partially collapsed to stop the furnace operation.

Therefore, in order to enhance the operational safety to the RHK, there is no gap between the refractory container and the refractory container as shown in FIG. 6 (a). In this case, there is no gap between the refractory container and the refractory container, And the uniformity of the heat treatment temperature is lowered.

8 (a) and 8 (b), the refractory vessels are stacked on the truck in a multi-stage manner. As shown in FIG. 8 (a) When the load is transferred, the damage to the objects to be burned and the refractory container due to the shaking can be reduced when the truck is moved to the inside of the main body, but the heat circulation is not good and the heat treatment temperature inside the furnace is varied.

On the other hand, if the gap is as shown in FIG. 8 (b), the temperature deviation due to the improvement of the heat circulation is reduced, but the risk of damage to the object to be sintered and the refractory container becomes large due to the shaking motion when moving the trolley. In some cases, the vessel collapses and accidents occur.

As described above, conventional refractory vessels have problems in heat circulation and safety in use during heat treatment.

It is an object of the present invention to provide a refractory container which is smoothly circulated and heat-treated in a heat treatment.

The objects of the present invention are not limited to the above-mentioned objects, and other objects not mentioned can be clearly understood by those skilled in the art from the following description.

The refractory container improved in thermal cycling and safety according to an embodiment of the present invention achieves the above-described object by means of the following solution.

First, in a refractory container mounted in an industrial furnace for heat treatment of a powder or an article, a convex portion may be formed on an outer wall of the refractory container.

Preferably, the convex portion may be provided at a corner or a central portion of the outer wall, and the convex portion may be installed perpendicularly or horizontally to the outer wall.

Preferably, the convex portion may be installed on an upper portion or a lower portion of the outer wall. The convex portion may be installed on the left side, the right side, the front side and the rear side of the outer side wall, or may be provided on either the left side, the right side, .

Preferably, the convex portion may be formed in an area of 40% or less of the area of the outer wall surface.

Meanwhile, the refractory container improved in heat circulation and safety according to another embodiment of the present invention achieves the above-described object by means of the following solution.

In the refractory container for heat treatment, the refractory container is formed of a hexahedron having a space of a predetermined volume for accommodating a powder or an article to be heat-treated, wherein the refractory container includes a front surface, a rear surface, a left surface and a right surface At least one surface may have a protruding block of a predetermined shape.

Preferably, the protruding block may be formed at the top, bottom or center of the outer edge of the refractory container, and the protruding block may be formed at the top, bottom or center of the outer front, back, left and right sides of the refractory container .

Preferably, the protruding block may be formed as a hexahedron having a protrusion height of 5 to 15 mm, and is integrally formed with the refractory container to prevent separation from the refractory container, wherein the refractory container and the protruding block are made of alumina (Al ₂ O ₃ ), silica (SiO ₂ ), magnesia (MgO), zirconia (ZrO ₂ ) and calcia (CaO).

The protruding block may be formed to occupy 5 to 30% of the entire area of the surface on which the protruding block is formed.

The refractory container improved in heat cycle and safety according to the embodiments of the present invention has convex portions or protruding blocks of a predetermined size formed on the outer wall surface, so that the circulation of heat is smooth during the heat treatment and the use is safe.

That is, the refractory container improved in thermal circulation and safety according to the embodiments of the present invention is easy to maintain the space between the refractory container and the refractory container, and the circulation of the heat inside the furnace is uniform and smooth and the uniformity of the heat treatment is improved. There is an advantageous effect that the straightness of movement is increased in the road, and there is no shaking in the bogie type road and the overturning accident does not occur.

Fig. 1 (a) is a general refractory vessel, and (b), (c), (d) and (e) are refractory vessels with improved thermocycling and safety according to the embodiments of the present invention.
FIG. 2 is a top view of a refractory container improved in thermal circulation and safety according to embodiments of the present invention, FIG. 3 is a side view of a refractory container improved in thermal circulation and safety according to embodiments of the present invention,
Fig. 4 is a view showing an example of a method of using the refractory vessel in the bogie type furnace, Fig. 5 is an example of a method of using the refractory vessel in the RHK furnace, Figs. 6 to 8 are views showing the arrangement of the refractory vessels in the heat treatment furnace, .

The term used in the present invention is a general term that is widely used at present. However, in some cases, there is a term selected arbitrarily by the applicant. In this case, the term used in the present invention It is necessary to understand the meaning.

1 (a) is a general refractory container, and (b), (c), (d), and (e) are refractory vessels with improved thermal circulation and safety according to the embodiments of the present invention.

FIG. 2 is a top view of a refractory container improved in thermal circulation and safety according to embodiments of the present invention, FIG. 3 is a side view of a refractory container improved in heat circulation and safety according to the embodiments of the present invention, Fig. 5 is an illustration of a method of using the refractory vessel in RHK, and Figs. 6 to 8 are examples of the arrangement and loading method of the refractory vessel in the heat treatment furnace.

Hereinafter, the refractory container 100 with improved thermocycling and safety according to an embodiment of the present invention will be described in detail with reference to FIGS. 1 to 8. FIG.

First, the refractory container 100 having improved thermal circulation and safety according to an embodiment of the present invention is provided with a heat exchanger 100 having a predetermined size on the outer wall surface of the refractory container 100 in order to smoothly circulate heat during heat treatment and to improve safety in use. The convex portion 110 is formed.

1 (b), 1 (c), 1 (d), and 1 (e) show a refractory container having an improved thermocycling and safety according to an embodiment of the present invention 100, the convex portion 110 is formed to improve the circulation of the heat and improve the stability of use.

The convex portion 110 of the refractory container 100 may be installed at the corner of the rectangular container 100 as shown in FIG. 2 (a) or may be installed at the center of the outer wall surface 4 as shown in FIG. 2 (b) It is possible.

The convex portion 110 may be installed vertically or horizontally on the side wall of the refractory container 100 or may be installed on the upper side of the side wall of the refractory container 100 as shown in FIG. Or may be provided at the lower part of the side wall as shown in Fig. 3 (b).

In addition, the convex portion 110 may be installed on all the outer walls of the refractory container 100 on the left and right, front and rear, and some of them may be omitted.

That is, it may be provided only in one of the left and right sides, the front side and the rear side, or may be provided in one side and the front side or the rear side at the same time.

The convex portion 110 of the refractory container 100 may have an area of 40% or less of the outer wall surface area, and preferably an area of 30% or less of the outer wall surface area in order to secure a heat circulation passage and reduce refractory material Respectively.

On the other hand, when the refractory vessel 100 having improved thermal circulation and safety according to an embodiment of the present invention is used for heat treatment in an industrial furnace, heat circulation is smooth and safe to use.

That is, in the typical continuous furnace RHK, it is possible to arrange the refractory containers as shown in FIGS. 6C and 6D so that the convex portions 110 on the side surface of the refractory container 100 are in close contact with each other, And the uniformity of the heat treatment temperature is improved.

On the other hand, when the conventional refractory container is arranged as shown in FIG. 6 (b), the refractory containers move individually while moving inside the furnace, causing a gap between the refractory containers and changing the direction of the refractory container. Since the convex portion 110 of the refractory container 100 and the convex portion 110 of the refractory container 100 move in close contact with each other in the refractory container 100 according to the embodiment, There is an advantage that the movement straightness of the refractory container 100 is improved and the possibility of occurrence of an accident is lowered.

8 (c) or 8 (d), it is possible to use the refractory container 100 according to the embodiment of the present invention in the non-continuous furnace-type furnace, Since the convex portions 110 are in close contact with each other, there is no shaking during movement of the carriage 150, so that the stability of use is improved and the heat circulation space portion 111 is connected up and down and left and right to increase heat treatment uniformity.

In order to manufacture the refractory container 100 having the convex portion 110 as described above, a mold or a gypsum mold having a space 120 having a predetermined volume in the form of a refractory container 100 having a convex portion 110 Each of the ceramic raw materials in powder form corresponding to the mixing ratio according to the characteristics (usage, use temperature, product shape, strength, etc.) required for the refractory container 100 is measured.

Then, water or an organic additive is added to the ceramic raw material, and the mixture is homogeneously mixed using a mixer. Then, the ceramic raw material is put into a mold and pressure is applied to produce a refractory container 100 shaped body.

Thereafter, the formed body is dried at a temperature between 50 ° C and 150 ° C to remove moisture, and the dried body is fired at a temperature of 1200-1700 ° C in a heat treatment furnace to have a certain strength, thereby improving the circulation of heat Thereby completing the refractory container 100 with improved stability in use.

Hereinafter, the refractory vessel 100 with improved thermocycling and safety according to another embodiment of the present invention will be described in detail.

The refractory container 100 having improved thermal circulation and safety according to another embodiment of the present invention is formed of a hexahedron in which a space 120 having a predetermined volume for accommodating a powder or an article to be heat-treated is formed.

In this case, the powder or article to be subjected to the heat treatment may be various powders or articles requiring heat treatment. However, the refractory container 100 according to another embodiment of the present invention may be manufactured by placing a lithium compound in the space 120 It is used for heat treatment.

On the other hand, the lithium compound is an important material used in various industrial fields and is mainly used as a positive electrode material of a lithium secondary battery.

At this time, the cathode active material containing lithium ion, which is an energy source of the lithium secondary battery, is used in the form of lithium metal oxide. In the lithium secondary battery, lithium ion and transition metal oxide are electrochemically inserted and desorbed according to charging and discharging, LiCoO ₂ , LiNiO ₂ , LiNi _x Co _y Mn _z O _₂ vary depending on the metal oxide.

Meanwhile, the lithium cathode active material is prepared by mixing a lithium compound such as Li ₂ CO ₃ or LiOH and a precursor of a transition metal (Co, Mn, Ni, Fe, etc.) at a predetermined ratio into a heat treatment vessel, A lithium compound and a transition metal precursor are reacted with each other to prepare a lithium metal composite oxide for a cathode active material of a lithium secondary battery.

At this time, since the characteristics of the lithium metal composite oxide for the cathode active material synthesized by the heat treatment conditions are sensitively changed, it is necessary to control the uniform heat treatment condition. For this purpose, the heat- .

Meanwhile, the refractory container 100 having improved thermal circulation and safety according to another embodiment of the present invention is formed of a hexahedron having a space portion 120 having a predetermined volume as described above. In this case, the hexahedron may be a rectangular parallelepiped or a cuboid However, it is preferably made of a cube.

As described above, the refractory container 100 made of a cubic body may have various sizes. In another embodiment of the present invention, the refractory container 100 is 200 to 400 mm in width and 5 to 150 mm in height.

The reason for limiting the size of the refractory container 100 is that the larger the size of the refractory container 100 is, the larger the internal volume is. However, when the size of the refractory container 100 is increased, Since cracks may be generated due to thermal shock due to temperature fluctuations in the inside and outside of the container during heating and cooling processes, it is limited to an optimal size to prevent such cracks.

In the refractory container 100 having improved thermal circulation and safety according to another embodiment of the present invention, at least one of the outer front surface, the rear surface, the left surface, and the right surface of the refractory container 100 has a protruding block 110 are formed.

1, the protruding block 110 has the same function as the convex portion 110 described in the embodiment of the present invention. The protruding block 110 may be formed at an upper portion, a lower portion, or a lower portion of the outer surface edge of the refractory container 100 Can be formed at the center.

In addition, the protruding block 110 may be formed at an upper portion, a lower portion, or a center of the outer front surface, the rear surface, the left surface, and the right surface of the refractory container 100 outside the above-described position.

Meanwhile, the protrusion block 110 may have various shapes, but in another embodiment of the present invention, the protrusion block 110 has a rectangular parallelepiped shape extending in the horizontal direction.

In addition, the protrusion height of the protrusion block 110 may be varied according to need. However, in another embodiment of the present invention, the protrusion height may be 5 to 15 mm.

The protruding height of the protruding block 110 is limited to 5 to 15 mm because if the protruding height is less than 5 mm, it is difficult to secure the circulation space of heat and gas between the refractory containers 100, This is to solve the problem that unreacted Li ₂ CO ₃ and LiOH remain due to the uncharged state of CO ₂ and H ₂ O gases generated during the heat treatment process due to the characteristic difference and the gas circulation being poor.

The protruding block 110 may be separately manufactured and adhered to one surface of the refractory container 100 using a ceramic adhesive.

However, in another embodiment of the present invention, the protruding block 110 is integrally formed with the refractory container 100 to prevent the protruding block 110 from being separated from the refractory container 100.

The method using the above-described ceramic adhesive has the following problems.

Since the refractory container 100 is repeatedly subjected to heat treatment at a room temperature and a high temperature (1200 to 1700 deg. C), the thermal expansion of the refractory container 100, the adhesive, and the protruding block 110 There is a problem that the adhesive surface is dropped during use several times or dozens of times due to the difference.

In another embodiment of the present invention, the protruding block 110 and the refractory container 100 are integrally formed by molding the protruding block 110 and the refractory container 100 together. It is made of the same material.

The more detailed description of this, the projecting block 110 and the refractory vessel 100 is alumina (Al ₂ O _3), silica (SiO _2), magnesia (MgO), zirconia (ZrO ₂₎ and calcia (CaO) , Or a mixture of at least two selected from the group consisting of:

Preferably, the sum of the components of alumina, silica, and magnesia is 90% or more in consideration of the heat resistance and corrosion resistance of the refractory container 100.

However, since the refractory container 100 in which the protruding block 110 is formed is difficult to be molded due to its morphological characteristics, it is difficult to mold A certain amount (at least 10% or more) of a material such as clay having a silica component that improves the property is added.

In addition, the refractory container 100 having improved thermocycling and safety according to another embodiment of the present invention may be constructed such that the protruding block 110 occupies 5 to 30% of the total area of the surface on which the protruding block 100 is formed .

The reason for limiting the charge area of the protruding block 110 to 5 to 30% is that the heat and gas circulation passage is insufficient when the ratio is more than 30%, and the increase of the heat capacity due to the increase in the weight of the refractory container 100, The amount of energy loss due to contact between the refractory containers 100 is increased. On the contrary, when the amount of energy is less than 5%, the contact area between the refractory containers 100 increases and the risk of breakage of the protruding block 110 increases. ) Was limited to 5 to 30%.

As a result, the refractory container 100 having improved thermal circulation and safety according to the embodiments of the present invention has the convex block 110 or the protrusion block 110 of a predetermined size formed on the outer wall surface through the above technical contents, It has a smooth circulation and safe use effect.

That is, the refractory container 100 improved in thermal circulation and safety according to the embodiments of the present invention can easily maintain the space between the refractory container and the refractory container, so that the circulation of heat inside the furnace can be uniform and smooth, In addition, in RHK, there is an excellent effect that the straightness of movement is increased, and there is no shaking in the bogie type road, and no overturning accident occurs.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is clearly understood that the same is by way of illustration and example only and is not to be taken by way of limitation, Various changes and modifications may be made by those skilled in the art.

100: Refractory vessel with improved thermal cycling and safety
110: protrusion, protrusion block
111: circulation space part
120:
130:
140:
150: Bogies
160: Roller
170: Yes Tropical
180:
190: Cooling zone

Claims (12)

1. A refractory container loaded inside an industrial furnace for heat treatment of a powder or an article,
And a convex portion is formed on an outer wall of the refractory container.
The method according to claim 1,
Wherein the convex portion is provided at an edge or a central portion of the outer wall.
The method according to claim 1,
And the convex portion is provided in the vertical or horizontal direction on the outer wall.
The method according to claim 1,
And the convex portion is provided on an upper portion or a lower portion of the outer wall.
The method according to claim 1,
Wherein the convex portion is provided on both the left side, the right side, the front side and the rear side of the outer wall, or is provided on only one of the left side, the right side, the front side and the back side.
The method according to claim 1,
And the convex portion is formed in an area of 40% or less of the area of the outer wall surface.
In a refractory vessel for heat treatment,
Wherein the refractory container is made of a powder or a hexahedron having a space having a predetermined volume for accommodating the article,
Wherein a protruding block having a predetermined shape is formed on at least one of an outer front surface, a rear surface, a left surface, and a right surface of the refractory container.
8. The method of claim 7,
Wherein the protruding block is formed at an upper portion, a lower portion, or a center of the outer edge of the refractory container.
8. The method of claim 7,
Wherein the protruding block is formed at an upper portion, a lower portion, or a center of an outer front surface, a rear surface, a left surface, and a right surface of the refractory container.
8. The method of claim 7,
Wherein the protruding block is formed in a hexahedron having a projection height of 5 to 15 mm.
8. The method of claim 7,
The projecting block doedoe to prevent the separation in the refractory container integrally molded with said refractory container, the refractory container and the projecting block of alumina (Al ₂ O _3), silica (SiO _2), magnesia (MgO), zirconia (ZrO ₂ ) and calcia (CaO), or a mixture of at least two or more thereof.
8. The method of claim 7,
Wherein the protruding block is formed to occupy 5 to 30% of a total area of the surface on which the protruding block is formed.

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