KR102386231B1 - Molten glass stirring chamber - Google Patents

Abstract

a stirred vessel configured to contain the molten glass; a cover disposed on the top of the stirring vessel; and a stirring body configured to penetrate the cover and stir the molten glass, wherein the cover includes a porous heat resistant material and an inorganic layer covering a surface of the porous heat resistant material.

Description

Molten glass stirring chamber

The present invention relates to a molten glass stirring chamber, and more particularly, to a molten glass stirring chamber capable of reducing defects occurring from a cover.

Equipment for manufacturing flat glass includes a stirring device for stirring molten glass.

The stirring device includes a stirring vessel containing molten glass, a cover covering the stirring vessel, and a stirring blade positioned in the stirring vessel. As time goes by, the platinum-based heat source disposed inside the cover reacts with oxygen in the atmosphere, and the oxidized platinum is incorporated into the glass in the form of platinum condensate, which may cause defects in the glass sheet.

The technical problem to be achieved by the present invention is to provide a molten glass stirring chamber in which defects generated from the cover are reduced.

The present invention in order to achieve the above technical problem, a stirring vessel configured to accommodate a molten glass; a cover disposed on the top of the stirring vessel; and a stirring body configured to penetrate the cover to agitate the molten glass, wherein the cover includes a porous cover body and an inorganic layer covering a surface of the cover body.

In some embodiments, the inorganic layer may be a glass layer. In some embodiments, the glass layer is silica (SiO ₂ ) about 80 wt% to about 90 wt%, boron oxide (B ₂ O ₃ ) about 1 wt% to about 3 wt%, alumina (Al ₂ O ₃ ) ) about 2 wt% to about 5 wt%, sodium oxide (Na ₂ O) about 1 wt% to about 3 wt%, potassium oxide (K ₂ O) about 2 wt% to about 4 wt%, zinc oxide (ZnO) about 2 wt% to about 6 wt%, and about 0.1 wt% to about 2 wt% zirconia (ZrO ₂ ).

In some embodiments, the cover body may include a recess and a heat source disposed in the recess. In some embodiments, the heat source may be kept surrounded by an inorganic filler in the recess. In some embodiments, the inorganic layer may cover at least an upper surface and a lower surface of the cover body, and an exposed portion of the inorganic filler. In some embodiments, the inorganic filler may be cement.

In some embodiments, the cover may further include a noble metal cladding layer that covers at least an upper surface and a lower surface of the cover body and is provided on the inorganic layer. In some embodiments, the cover may further include a refractory oxide layer covering a surface of the noble metal cladding layer facing the inside of the stirring vessel.

The cover has a center hole through which the stirring body passes, and is divided into a first body and a second body along a boundary area, and the first body has a sheet portion protruding in a horizontal direction along the boundary area. can be provided. In some embodiments, the seat part may protrude so as to at least partially overlap the second body. The seat portion may be provided at a lower portion of the first body facing the inside of the stirring vessel.

Another aspect of the present invention includes a stirred vessel configured to contain molten glass; a cover disposed on the top of the stirring vessel; and a stirring body configured to penetrate the cover and agitate the molten glass, wherein the cover has a central hole through which the stirring body passes, and a first body and a second body along a boundary region extending through the central hole It has a porous cover body divided into, and provides a molten glass stirring chamber, characterized in that the first body is provided with a sheet portion protruding in the horizontal direction along the boundary region.

In some embodiments, the seat part may protrude so as to at least partially overlap the second body.

In some embodiments, the surface of each of the first body and the second body may be coated with an inorganic layer. In some embodiments, a noble metal cladding layer may be further provided on a lower portion of the first body, and the sheet portion may be attached to a surface of the noble metal cladding layer.

Another aspect of the present invention is a stirred vessel configured to contain molten glass;

a cover disposed on the top of the stirring vessel; and a stirring body configured to agitate the molten glass through the cover, wherein the cover comprises a noble metal cladding layer on at least a lower surface, wherein a surface of the noble metal cladding layer in a direction toward the molten glass is CaO about 3 wt% (wt%) to about 5 wt%, SiO ₂ about 0.2 wt% to about 1 wt%, Al ₂ O ₃ about 0.2 wt% to about 1 wt%, HfO ₂ about 0.5 wt% to about 3.5 wt% and a molten glass stirring chamber coated with a refractory oxide layer containing the remainder ZrO ₂ .

In some embodiments, the refractory oxide layer may further include about 0.01 wt% to about 0.3 wt% of Fe ₂ O ₃ and about 0.01 wt% to about 0.9 wt% of MgO.

In some embodiments, the thickness of the refractory oxide layer may be between about 2 mils and about 8 mils.

In some embodiments, the cover has a central hole through which the stirring body passes, and has a porous cover body divided into a first body and a second body along a boundary region extending through the central hole, Each of the first body and the second body may have surfaces covered with an inorganic layer, and a sheet portion protruding in a horizontal direction along the boundary region may be provided on the first body.

The molten glass stirring chamber according to embodiments of the present invention has an effect of reducing defects occurring from the cover.

1 is a conceptual diagram showing a glass manufacturing apparatus according to an embodiment of the present invention.
2 is a perspective view showing a molten glass stirring chamber according to an embodiment of the present invention.
3 is a perspective view showing a first body according to an embodiment of the present invention.
FIG. 4 is a cross-sectional view taken along line IV-VI' of FIG. 3 .
FIG. 5 is a graph conceptually illustrating a method of defining an interface between a cover body and an inorganic layer with respect to a cross-section taken along line VV' of FIG. 4 .
6 is a side cross-sectional view showing a first body according to another embodiment of the present invention.
7A to 7C are side cross-sectional views sequentially illustrating a method for manufacturing a first body according to embodiments of the present invention.
8 is a side cross-sectional view showing a first body according to another embodiment of the present invention.
9A and 9B are perspective views illustrating a method of forming a refractory oxide layer on a surface of a first body according to an embodiment of the present invention.
10 shows a first body of a cover according to an embodiment of the present invention.
11A and 11B are cross-sectional views illustrating a first body of a cover according to other embodiments of the present invention.
12 is a conceptual diagram illustrating a helium gas leak test apparatus for testing the performance of an inorganic layer according to an embodiment of the present invention.
13 is a graph showing the results of performing a helium gas leak test for Example 1 and Comparative Example 1, respectively.
14A and 14B are exploded perspective views illustrating samples subjected to a sagging comparison experiment with respect to Example 2, Example 3, Comparative Example 2, and Comparative Example 3;
15 is a graph showing the results of performing a sagging comparison experiment with respect to Example 2, Example 3, Comparative Example 2, and Comparative Example 3.

Hereinafter, preferred embodiments of the present invention concept will be described in detail with reference to the accompanying drawings. However, the embodiments of the inventive concept may be modified in various other forms, and the scope of the inventive concept should not be construed as being limited by the embodiments described below. The embodiments of the inventive concept are preferably interpreted as being provided in order to more completely explain the inventive concept to those of ordinary skill in the art. The same symbols refer to the same elements from time to time. Furthermore, various elements and regions in the drawings are schematically drawn. Accordingly, the inventive concept is not limited by the relative size or spacing drawn in the accompanying drawings.

Terms such as first, second, etc. may be used to describe various elements, but the elements are not limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the inventive concept, a first component may be referred to as a second component, and conversely, the second component may be referred to as a first component.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the inventive concept. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, expressions such as "comprises" or "have" are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification is present, but one or more other features or It should be understood that the existence or addition of numbers, operations, components, parts or combinations thereof is not precluded in advance.

Unless defined otherwise, all terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the inventive concept belongs, including technical and scientific terms. In addition, commonly used terms as defined in the dictionary should be construed as having a meaning consistent with their meaning in the context of the relevant technology, and unless explicitly defined herein, in an overly formal sense. It will be understood that they shall not be construed.

In cases where certain embodiments may be implemented otherwise, a specific process sequence may be performed different from the described sequence. For example, two processes described in succession may be performed substantially simultaneously, or may be performed in an order opposite to the described order.

In the accompanying drawings, variations of the illustrated shapes can be expected, for example depending on manufacturing technology and/or tolerances. Accordingly, the embodiments of the present invention should not be construed as limited to the specific shape of the region shown in the present specification, but should include, for example, changes in shape resulting from the manufacturing process. As used herein, all terms “and/or” include each and every combination of one or more of the recited elements.

1 is a conceptual diagram showing a glass manufacturing apparatus 1 according to an embodiment of the present invention.

Referring to FIG. 1 , the glass manufacturing apparatus 1 according to an embodiment of the present invention includes a melting vessel 100 , a clarification vessel 200 , a molten glass stirring chamber 300 , and a delivery vessel 500 . ), and a molding device 700 . Although in other embodiments the glass making apparatus 1 is capable of manufacturing various other glass articles such as glass rods, glass tubes, glass containers and glass seals, according to some embodiments, the glass making apparatus 1 ) can manufacture sheet-type glass.

Melting vessel 100 , clarification vessel 200 , molten glass stirring chamber 300 , transfer vessel 500 , and forming apparatus 700 are glass making process stations located in series, which are predetermined for the manufacture of glass articles. It may be a space in which the processes of According to some embodiments, the processes for manufacturing may be a down draw or slot draw fusion molding process. According to some embodiments, the manufacturing processes performed by the glass manufacturing apparatus 1 may be a slot-draw fusion molding process (including a double fusion process), a float glass forming process, or a rolling process.

According to some embodiments, the melting vessel 100 , the clarification vessel 200 , the molten glass stirring chamber 300 , the transfer vessel 500 , and the forming apparatus 700 are platinum or platinum-rhodium, platinum-iridium and metals containing platinum, such as combinations thereof. According to some embodiments, the melting vessel 100 , the clarification vessel 200 , the molten glass stirring chamber 300 , the transfer vessel 500 , and the forming apparatus 700 are palladium, rhenium, ruthenium and osmium, or their It may include other metals such as alloys. According to some embodiments, the forming apparatus 700 may include a ceramic material or a glass-ceramic material.

The melting vessel 100 may be supplied with the batch material 11 from the storage vessel 10 . The batch material 11 is introduced into the melting vessel 100 by a batch transmission device 13 , which is powered by a drive device 15 . A selective controller 17 may be configured to operate the drive device 15 . The selection controller 17 may control the drive device 15 to introduce a desired amount of the batch material 11 into the melting vessel 100 as shown by arrow a1 . According to some embodiments, a glass level probe 19 may measure a molten glass MG level in a standpipe 21 . The glass level probe 19 may be configured to transmit information about the measured level of the molten glass MG to the optional controller 17 via the communication line 23 .

According to some embodiments, the clarification vessel 200 may be connected to the melting vessel 100 by a first conduit 150 . The first conduit 150 provides a passage through which the molten glass MG can flow therein, and the same applies to the second and third conduits 250 and 350 to be described later. The first conduit 150 includes a material that is electrically conductive and can be used even under high temperature conditions. According to some embodiments, the first through third conduits 150 , 250 , 350 may be made of platinum or a platinum-containing metal such as platinum-rhodium, platinum-iridium, and combinations thereof. According to some embodiments, the first through third conduits 150 , 250 , 350 may be formed of refractory metals such as molybdenum, palladium, rhenium, tantalum, titanium, tungsten, ruthenium, osmium, zirconium, and alloys thereof and / or zirconium dioxide.

According to some embodiments, the clarification vessel 200 may serve as a purification tube. According to some embodiments, the clarification vessel 200 may be located downstream of the melting vessel 100 . The clarification container 200 may accommodate the glass MG molten in the melting container 100 . According to some embodiments, a high-temperature process for removing blisters (gas phase inclusions) included in the molten glass MG may be performed in the clarification vessel 200 . According to some embodiments, the clarification vessel 200 may heat the molten glass MG to remove blisters in the molten glass MG while the molten glass MG passes through the clarification vessel 200 . . According to some embodiments, when the molten glass MG is heated in the clarification vessel 200 , the fining agent included in the molten glass MG causes a redox reaction to cause oxygen and other substances in the molten glass MG. gases can be removed. Specifically, the blister contained in the molten glass MG may include, for example, oxygen (O ₂ ), carbon dioxide (CO ₂ ), and/or sulfur dioxide (SO ₂ ). By the reduction reaction of the clarifier, the blister can combine with oxygen to increase its volume. After the blister with increased volume floats to the free surface of the molten glass MG in the clarification vessel 200 , it may be removed through the surface of the molten glass MG. The blister may be discharged to the outside through the gaseous space of the upper portion of the clarification container (200).

According to some embodiments, a molten glass stir chamber 300 , such as a stir chamber, is located downstream of the clarification vessel 200 . In the molten glass stirring chamber 300 , a homogenization process may be performed on the molten glass MG supplied from the clarification vessel 200 . In the molten glass stirring chamber 300 , a stirring body 310 that rotates relative to the molten glass stirring chamber 300 to flow the molten glass MG and mix them may be provided. The stirring body 310 may stir the molten glass MG to have a uniform component before the molten glass MG leaves the molten glass stirring chamber 300 .

A delivery vessel 500 may be located downstream of the molten glass stirring chamber 300 . The delivery vessel 500 may be connected to the molten glass stirring chamber 300 by a third conduit 350 . An outlet conduit 600 may be connected to the delivery vessel 500 . The molten glass MG may be delivered to the inlet 650 of the forming apparatus 700 via an outlet conduit 600 .

The forming apparatus 700 may receive the molten glass MG from the delivery container 500 . In other embodiments, the forming apparatus may form the molten glass into a material having other shapes such as rods, tubes, seals, etc., but the forming apparatus 700 converts the molten glass MG into a sheet-shaped glass. It can be molded into products. For example, forming apparatus 700 may include a fusion drawing machine for forming molten glass MG into a continuous ribbon of glass. The molten glass MG flowing into the forming apparatus 700 may flow while overflowing in the forming apparatus 700 . The overflowing molten glass MG can be drawn down by gravity and a combination of suitably positioned rolls such as edge roll 750 and pulling rolls 800, and pulled down to form a molten glass ribbon.

2 is a perspective view showing a molten glass stirring chamber 300 according to an embodiment of the present invention.

Referring to FIG. 2 , the molten glass stirring chamber 300 includes a stirring vessel 320 configured to receive molten glass MG, a cover 330 disposed on the top of the stirring vessel 320 , and the cover ( It may include a stirring body 310 configured to pass through 330 to stir the molten glass MG.

The stirring vessel 320 may be connected to the second conduit 250 and the third conduit 350 . As described above, the molten glass MG is introduced into the stirring vessel 320 through the second conduit 250 , and is discharged from the stirring vessel 320 through the third conduit 350 .

The stirring body 310 may have a stirring rod 314 and a plurality of blades 312 attached thereto.

A cover 330 covering the opening of the stirring vessel 320 may be provided on the upper portion of the stirring vessel 320 . A center hole 338 through which the stirring rod 314 passes may be provided in the center of the cover 330 . A heat source 332 may be provided inside the cover 330 .

The cover 330 may include two bodies, that is, a first body 330a and a second body 330b. The first body 330a and the second body 330b may be separated from each other with a boundary region extending through the central hole 338 therebetween. 2 shows an example in which the cover 330 is separated into two bodies, but in another embodiment, the cover 330 may be separated into three or more bodies.

The first body 330a and the second body 330b may include a cover body 334 and a heat source 332 embedded in the cover body 334, respectively.

The heat source 332 has platinum or a platinum alloy as a component, and heat may be generated when power is applied. Specifically, the heat source 332 may be pure platinum or an alloy of platinum. The platinum alloy may be an alloy of platinum with at least one of rhodium (Rh), iridium (Ir), ruthenium (Ru), palladium (Pd), and osmium (Os).

The cover body 334 may be made of a refractory material. In some embodiments, the cover body 334 may be made of a porous material. For example, the cover body 334 may be made of materials such as crystallite HF339 (available from BUCHER Emhart Glass) or AN485 (available from Saint Gobain).

3 is a perspective view showing a first body 330a according to an embodiment of the present invention, and FIG. 4 is a cross-sectional view taken along line IV-IV' of FIG. 3 . Here, the first body (330a) will be described as a reference, but those skilled in the art will understand that the second body (330b) may be equally applied. Also, those skilled in the art will understand that the cover 330 may be divided into three or more bodies, and the following discussion may be equally applied to additional bodies accordingly.

Referring to FIGS. 3 and 4 , recesses 334R for accommodating the heat source 332 may be formed in the cover body 334 . The recesses 334R may extend in the viewing direction of FIG. 4 , or may extend in another direction such as a circumferential direction or a radial direction of the cover body 334 . A heat source 332 may be accommodated in the recess 334R.

The heat source 332 may be buried and protected by the inorganic filler 334f in the recess 334R. The inorganic filler 334f may be, for example, cement.

As shown in FIG. 4 , the inorganic filler 334f may be at least partially exposed from the cover body 334 . In some embodiments, one surface of the inorganic filler 334f may be coplanar with one surface of the cover body 334 .

The surface of the cover body 334 may be covered by the inorganic layer 336 . In some embodiments, the inorganic layer 336 may be a ceramic layer. In some embodiments, the inorganic layer 336 may be a glass layer containing silica as a main component. For example, the inorganic layer 336 may include about 80% to about 90% by weight of silica (SiO ₂ ), about 1% to about 3% by weight of boron oxide (B ₂ O ₃ ), and about 3% by weight of alumina (Al ₂ O ₃ ) ) about 2 wt% to about 5 wt%, sodium oxide (Na ₂ O) about 1 wt% to about 3 wt%, potassium oxide (K ₂ O) about 2 wt% to about 4 wt%, zinc oxide (ZnO) About 2 wt% to about 6 wt%, and about 0.1 wt% to about 2 wt% of zirconia (ZrO ₂ ) may be included.

In some embodiments, the inorganic layer 336 may cover the upper surface of the cover body 334 . In some embodiments, the inorganic layer 336 may cover a lower surface of the cover body 334 . In some embodiments, the inorganic layer 336 may cover the exposed surface of the inorganic filler 334f.

Platinum contained in the heat source 332 is lost as PtO ₂ in the gas phase in contact with oxygen at a high temperature, and is contained as an inclusion in the molten glass MG in the stirring chamber 300 at an undesirable location, for example, to form a condensate. It is desirable to prevent or reduce contact with oxygen because it can be deposited as a By providing the inorganic layer 336 , it is possible to prevent or reduce platinum contained in the heat source 332 from contacting oxygen.

The inorganic layer 336 may have a thickness of about 1 mm to about 5 mm. If the thickness of the inorganic layer 336 is too thick, there is a risk of generation of particles due to peeling of the inorganic layer 336. Conversely, if the thickness of the inorganic layer 336 is too thin, oxidation of platinum contained in the heat source is reduced. The prevention effect may be insufficient.

Meanwhile, when the cover body 334 is porous, the interface between the cover body 334 and the inorganic layer 336 may be ambiguous. In other words, the inorganic layer 336 may partially penetrate into the pores of the cover body 334 in a region in contact with the porous cover body 334 .

FIG. 5 is a graph conceptually illustrating a method of defining an interface between the cover body 334 and the inorganic layer 336 with respect to a cross-section taken along the line V-V' of FIG. 4 . In FIG. 5 , the horizontal axis indicates a position along the line V-V′ of FIG. 4 , and the vertical axis indicates a mass fraction of a material forming the inorganic layer 336 and a material forming the cover body 334 . Referring to FIG. 5 , there may be a section in which the weight fraction of the cover body 334 and the inorganic layer 336 is gradually changed around the interface IF where the cover body 334 and the inorganic layer 336 come into contact with each other. there is. Here, an imaginary interface at which the weight fraction of the cover body 334 and the inorganic layer 336 is approximately 0.5 may be defined as the interface between the cover body 334 and the inorganic layer 336 .

6 is a side cross-sectional view showing a first body (330a') according to another embodiment of the present invention. The first body 330a' of FIG. 6 is different from the first body 330a of FIG. 4 in that the inorganic layer 336a is formed only on the lower surface. Accordingly, the following description will focus on these differences, and overlapping descriptions will be omitted.

Referring to FIG. 6 , the inorganic layer 336a is not formed over the entire surface of the cover body 334 . In some embodiments, the inorganic layer 336a may be provided to coat only the surface on which the heat source 332 is provided. In some embodiments, inorganic layer 336a may cover the exposed surface of inorganic filler 334f. In some embodiments, inorganic layer 336a may cover a surface of cover body 334 that is substantially coplanar with an exposed surface of inorganic filler 334f. In some embodiments, the inorganic layer 336a may not cover a surface of the cover body 334 that is not substantially coplanar with the exposed surface of the inorganic filler 334f.

Since the shortest path of oxygen oxidizing platinum in the heat source 332 is mainly the surface on the side where the inorganic filler 334f is located, the inorganic layer 336a is formed on only one surface (that is, the side where the recess 334R is formed). Even if it is formed only on the surface of ), the effect of preventing oxidation and loss of Pt as shown in FIG. 4 can be obtained similarly. Furthermore, the first body 330a ′ of the embodiment of FIG. 6 is relatively economically advantageous and easy to manufacture compared to the embodiment of Comparative Example 4 because the amount of the inorganic layer 336a used is smaller. In addition, the first body 330a' has a lighter load (because the amount of the inorganic layer 336 is smaller) than the first body 330a of FIG. This could happen less.

7A to 7C are side cross-sectional views sequentially illustrating a method for manufacturing the first body (330a, 330a') according to embodiments of the present invention.

Referring to FIG. 7A , recesses 334R are formed in the lower surface of the cover body 334 . The recesses 334R may have a size sufficient to accommodate the heat source 332 (see FIG. 7B ) therein.

Referring to FIG. 7B , a heat source 332 may be disposed in the recess 334R, and a space between the inner surface of the recess 334R and the heat source 332 may be filled with an inorganic filler 334f. Since the material of the inorganic filler 334f has been described in detail above, a detailed description thereof will be omitted.

Referring to FIG. 7C , an inorganic ceramic material layer 336p is formed on the surface of the cover body 334 and the inorganic filler 334f. The inorganic ceramic material layer 336p may be, for example, a slurry layer in which an inorganic ceramic material is dispersed in a dispersion medium. In some embodiments, the inorganic ceramic material layer 336p, silica (SiO ₂ ) about 80 wt% to about 90 wt%, boron oxide (B ₂ O ₃ ) about 1 wt% to about 3 wt%, About 2% to about 5% by weight of alumina (Al ₂ O ₃ ), about 1% to about 3% by weight of sodium oxide (Na ₂ O), about 2% to about 4% by weight of potassium oxide (K ₂ O) , from about 2% to about 6% by weight of zinc oxide (ZnO), and from about 0.1% to about 2% by weight of zirconia (ZrO ₂ ) with a dispersion medium such as water from approximately 1:2 to 2:1 It may be mixed in a weight ratio of

The inorganic ceramic material layer 336p may be formed using a method such as brushing, spraying, dip coating, or spin coating, but is not limited thereto.

Subsequently, when the inorganic ceramic material layer 336p is annealed at a temperature of about 800° C. to about 2000° C. for about 10 seconds to about 60 minutes, the inorganic layer 336a is formed and the first body 330a shown in FIG. ) can be obtained.

The first body 330a ′ shown in FIG. 6 may be manufactured in the same manner as the methods described with reference to FIGS. 7A to 7C , except that the inorganic ceramic material layer 336p is formed only on the lower surface in FIG. 7C . can

8 is a side cross-sectional view showing a first body 330a" according to another embodiment of the present invention. The first body 330a" of FIG. 8 has a noble metal cladding layer compared to the first body 330a of FIG. There is a difference from 333 in that a refractory oxide layer 337 is further included on one surface of the noble metal cladding layer 333 . Accordingly, the following description will focus on these differences, and overlapping descriptions will be omitted.

The noble metal cladding layer 333 may be formed on at least the upper surface 333US or the lower surface 333LS of the first body 330a". The noble metal is platinum (Pt), gold (Au), or ruthenium ( Defined as a metal that has resistance to oxidation and corrosion, such as Ru), rhodium (Rh), palladium (Pd), silver (Ag), osmium (Os), iridium (Ir), copper (Cu), and rhenium (Re). In some embodiments, the noble metal cladding layer 333 may be respectively formed on an upper surface and a lower surface of the cover body 334. In some embodiments, the noble metal cladding layer 333 ) may also be formed on the inner surface of the central hole 338 (corresponding to the sidewall SW portion of FIG. 8 ).

The noble metal cladding layer 333 may include, for example, platinum or a platinum alloy. For example, the platinum alloy may be an alloy of platinum with one or more of rhodium (Rh), iridium (Ir), ruthenium (Ru), palladium (Pd), and osmium (Os). .

A refractory oxide layer 337 may be provided on the lower surface 333S of the noble metal cladding layer 333 . The refractory oxide layer 337 is made of a highly refractory oxide material. The lower surface 333LS may be a surface facing the stirring vessel 320 . The refractory oxide layer 337 covers and reduces the area of platinum or platinum alloy exposed to high temperature so that the redox reaction of platinum and the reaction products thereof are condensed on the inner surface of the cover and the stirring vessel and , it is possible to reduce the possibility that the reaction products are incorporated into the molten glass (MG). Thereby, it is possible to reduce product defects due to platinum condensation.

The thickness of the refractory oxide layer 337 may range from about 1 mil (=0.001 inch) to about 10 mils. In some embodiments, the thickness of the refractory oxide layer 337 may be from about 2 mils (=0.001 inches) to about 8 mils.

The lower surface 333LS of the noble metal cladding layer 333 on which the refractory oxide layer 337 is formed may be roughened. In some embodiments, the roughness Ra of the lower surface 333LS of the noble metal cladding layer 333 may be about 0.1 μm to about 50 μm as measured by the BS EN ISO 4287:2000 standard. where Ra is the arithmetic mean roughness, which indicates the degree of deviation from the arithmetic mean of the roughness profile. When the roughness Ra is too large, the flatness after the refractory oxide layer 337 is formed may be insufficient. When the roughness Ra is too small, the adhesion between the refractory oxide layer 337 and the noble metal cladding layer 333 may be insufficient.

9A and 9B are perspective views illustrating a method of forming a refractory oxide layer 337 on the surface of the first body 330a according to an embodiment of the present invention.

Referring to FIG. 9A , the outer surface of the first body 330a may be coated with an inorganic layer 336 . A noble metal cladding layer 333 may be provided on an upper surface and a lower surface of the first body 330a. Also, a metal cladding layer 333 may be provided at least partially on the sidewall SW of the first body 330a.

Subsequently, the lower surface 333S of the noble metal cladding layer 333 may be roughened. 9A illustrates a state in which the first body 330a is turned over so that the lower surface 333S faces upward for convenience of understanding. The roughening may be performed, for example, by a method such as sand blasting, but the present invention is not limited thereto. As a result, a roughened lower surface 333SB can be obtained.

Referring to FIG. 9B , a refractory oxide layer 337 is formed on the roughened lower surface 333SB.

The refractory oxide layer 337 may be a material layer containing zirconia (ZrO ₂ ) as a main component. In some embodiments, the refractory oxide layer 337 includes about 3 wt% (wt%) to about 5 wt% of calcium oxide (CaO), about 0.2 wt% to about 1 wt% of silica (SiO ₂ ), alumina (Al ₂ O ₃ ) about 0.2 wt % to about 1 wt %, hafnium oxide (HfO ₂ ) about 0.5 wt % to about 3.5 wt %, and the balance zirconia (ZrO ₂ ) and unavoidable impurities. The refractory oxide layer 337 may further include about 0.01 wt% to about 0.3 wt% of iron oxide (Fe ₂ O ₃ ) and about 0.01 wt% to about 0.9 wt% of magnesium oxide (MgO).

In some embodiments, the refractory oxide layer 337 comprises about 1 wt% (wt%) to about 2 wt% of hafnium oxide (HfO ₂ ), about 2.5 wt% to about 4.5 wt% of calcium oxide (CaO), silica (SiO ₂ ) about 0.2 wt % to about 1.0 wt %, alumina (Al ₂ O ₃ ) about 0.3 wt % to about 1.2 wt %, iron oxide (Fe ₂ O ₃ ) about 0.01 wt % to about 0.2 wt %, titania ( TiO ₂ ) about 0.05 wt% to about 0.2 wt%, about 0.01 wt% to about 0.1 wt% of magnesium oxide (MgO), the balance zirconia (ZrO ₂ ) and unavoidable impurities.

In some embodiments, the refractory oxide layer 337 may be formed by melting raw material powder with plasma and then spraying it. 9B illustrates a state in which a portion of the lower surface 333SB is exposed to indicate that the refractory oxide layer 337 is formed on the lower surface 333SB. However, in other embodiments, the refractory oxide layer 337 may be formed on the entire surface of the roughened lower surface 333SB.

10 shows a first body 331a of a cover according to an embodiment of the present invention. The first body 331a may constitute the cover 330 together with the second body 331b.

Referring to FIG. 10 , the lower portion of the refractory oxide layer 337 includes a sheet portion 339 protruding and extending along the boundary region BD between the first body 331a and the second body 331b. may be provided.

The seat portion 339 is attached to the lower surface of the first body 331a, but the protruding portion may at least partially overlap the second body 331b. In other words, the seat portion 339 may cover substantially all of the boundary area BD except for a portion of the central hole 338 . In some embodiments, the width G1 of the seat portion 339 protruding from the first body 331a toward the second body 331b is the first body 331a and the second body 331b. It may be greater than the interval G2 between 331b.

The sheet part 339 may be made of a metal or an inorganic refractory material. In some embodiments, the sheet portion 339 may be made of a metal such as platinum or an alloy of platinum. In some other embodiments, the sheet part 339 may include a silica-based, zirconia-based, or alumina-based inorganic refractory material. In some embodiments, the sheet part 339 may be an alloy of platinum and rhodium.

11A and 11B are cross-sectional views illustrating first bodies 331a' and 331a″ of a cover according to other embodiments of the present invention.

Referring to FIG. 11A , the sheet part 339 may be directly attached to the surface of the inorganic layer 336 . The first body 331a ′ of FIG. 11A may be the same as that in the embodiment of FIG. 10 , in which the refractory oxide layer 337 and the noble metal cladding layer 333 are omitted.

Referring to FIG. 11B , the sheet part 339 may be directly attached to the surface of the noble metal cladding layer 333 . The first body 331a″ of FIG. 11B may be the same as that in which the refractory oxide layer 337 is omitted in the embodiment of FIG. 10 .

Hereinafter, the configuration and effect of the present invention will be described in more detail with reference to specific examples and comparative examples, but these examples are only for clearer understanding of the present invention and are not intended to limit the scope of the present invention.

12 is a conceptual diagram illustrating a helium gas leak test apparatus for testing the performance of an inorganic layer according to an embodiment of the present invention.

Referring to FIG. 12 , the sample SA is fixed to the opening 54 of the chamber 51 having the opening 54 on one side. To prevent leakage between the sample SA and the chamber 51 , the inlet valve 52 is opened while the outlet valve 53 is closed to supply helium (He) gas at a predetermined pressure.

If there are more paths through which the gas can pass through the sample SA, the amount of helium leak detected through the helium sensor 43 will be larger. Conversely, if the path through which the gas can pass through the sample SA is smaller, the amount of helium leakage detected through the helium sensor 43 will be smaller.

Silica (SiO ₂ ) 85.05, boron oxide (B ₂ O ₃ ) 2.25 wt %, alumina (Al ₂ O ₃ ) 3.25 wt %, sodium oxide (Na ₂ O) on a porous AN485 (available from Saint Gobain company) sample ) 1.7 wt %, potassium oxide (K ₂ O) 2.5 wt %, zinc oxide (ZnO) 4.1 wt %, and zirconia (ZrO ₂ ) 1.15 wt % An inorganic layer containing 1.15 wt % was formed to a thickness of about 3 mm.

The sample having the inorganic layer (Example 1) and the sample without the inorganic layer (Comparative Example 1) were respectively fixed to the opening of the chamber, and then a helium gas leak test was performed.

As a result, as shown in FIG. 13 , when the inorganic layer was formed, it was found that the gas leak was reduced to less than 1/4 compared to the case where the inorganic layer was not formed. Therefore, it can be seen that the inorganic layer can prevent the platinum contained in the heat source from being oxidized.

14A and 14B are exploded perspective views illustrating samples subjected to a sagging comparison experiment with respect to Example 2, Example 3, Comparative Example 2, and Comparative Example 3;

A recess 61r is formed on the surface of the body sample 61 in the form of a bar in the longitudinal direction, a heat source (not shown) and an inorganic filler 63 are formed in the recess 61r, and then inorganic ceramic is formed thereon. Layer 67 was formed (Example 2). It was manufactured in the same manner as in Example 2 except that the extending direction of the recess 65r was changed to a direction perpendicular to the longitudinal direction (Example 3). For comparison, samples of Comparative Examples 2 and 3 were prepared, which were identical to the samples of Examples 2 and 3, respectively, except that the inorganic ceramic layer 67 was not formed.

After supporting them over two supports 69 spaced apart from each other at a predetermined interval, they were left at 1500° C. for 3 days. Thereafter, the sagging length at the center between the two supports 69 was measured to obtain a result as shown in FIG. 15 . The sagging length is the difference between the initial height at the center and the height after standing at 1500° C. for 3 days.

Referring to FIG. 15 , it can be seen that the inorganic ceramic layer 67 also contributes to reducing the sag of the samples regardless of the extending direction of the recess. The sag length of Example 2 is less than 1/3 of the sag length of Comparative Example 2. The sag length of Example 3 is approximately half the sag length of Comparative Example 3.

Although the embodiments of the present invention have been described in detail as described above, those of ordinary skill in the art to which the present invention pertains, without departing from the spirit and scope of the present invention as defined in the appended claims The present invention may be practiced with various modifications. Accordingly, modifications of future embodiments of the present invention will not depart from the teachings of the present invention.

1: glass making apparatus 10: storage container
100: melting vessel 150, 250, 350: conduit
200: clarification vessel 300: molten glass stirring chamber
310: stirring body 314: stirring rod
312: blade 320: stirring vessel
330: covers 330a, 331a, 331a', 331a": first body
330b, 331b: second body 332: heat source
333: precious metal cladding layer 334: cover body
334f: inorganic filler material 334R: recess
336: inorganic layer 337: refractory oxide layer
338: central hole 339: seat portion
500: delivery vessel 600: outlet conduit
650: inlet 700: forming device

Claims (20)

a stirred vessel configured to contain the molten glass;
a cover disposed on the top of the stirring vessel; and
a stirring body configured to agitate the molten glass through the cover;
including,
The cover comprises a porous cover body and an inorganic layer covering the surface of the cover body,
The inorganic layer is silica (SiO ₂ ) 80 wt% to 90 wt%, boron oxide (B ₂ O ₃ ) 1 wt% to 3 wt%, alumina (Al ₂ O ₃ ) 2 wt% to 5 wt%, sodium oxide (Na ₂ O) 1 wt% to 3 wt%, potassium oxide (K ₂ O) 2 wt% to 4 wt%, zinc oxide (ZnO) 2 wt% to 6 wt%, and zirconia (ZrO ₂ ) 0.1 wt% to 2% by weight of the molten glass stirring chamber. delete delete The method of claim 1,
The molten glass stirring chamber, characterized in that the cover body comprises a recess and a heat source disposed in the recess. 5. The method of claim 4,
The molten glass stirring chamber, characterized in that the heat source is surrounded and maintained by the inorganic filler in the recess. 6. The method of claim 5,
and the inorganic layer covers at least the upper and lower surfaces of the cover body and the exposed portion of the inorganic filler. 7. The method of claim 6,
The molten glass stirring chamber, characterized in that the inorganic filler is cement. 8. The method according to any one of claims 1 and 4 to 7,
and the cover further comprises a noble metal cladding layer provided over the inorganic layer and covering at least an upper surface and a lower surface of the cover body. 9. The method of claim 8,
and the cover further comprises a refractory oxide layer covering the inner-facing surface of the stirring vessel of the noble metal cladding layer. 8. The method according to any one of claims 1 and 4 to 7,
The cover has a center hole through which the stirring body passes, and is divided into a first body and a second body along a boundary area,
The molten glass stirring chamber, characterized in that the first body is provided with a sheet portion protruding in the horizontal direction along the boundary region. 11. The method of claim 10,
The molten glass stirring chamber, characterized in that the seat portion protrudes so as to at least partially overlap the second body. 12. The method of claim 11,
The sheet portion is a molten glass stirring chamber, characterized in that provided in the lower portion of the first body facing the inside of the stirring vessel. a stirred vessel configured to contain the molten glass;
a cover disposed on the top of the stirring vessel; and
a stirring body configured to agitate the molten glass through the cover;
including,
The cover has a central hole through which the stirring body passes and has a porous cover body divided into a first body and a second body along a boundary region extending through the central hole,
The first body is provided with a sheet portion protruding in the horizontal direction along the boundary region,
The first body and the second body are each covered with an inorganic layer,
The inorganic layer is silica (SiO ₂ ) 80 wt% to 90 wt%, boron oxide (B ₂ O ₃ ) 1 wt% to 3 wt%, alumina (Al ₂ O ₃ ) 2 wt% to 5 wt%, sodium oxide (Na ₂ O) 1 wt% to 3 wt%, potassium oxide (K ₂ O) 2 wt% to 4 wt%, zinc oxide (ZnO) 2 wt% to 6 wt%, and zirconia (ZrO ₂ ) 0.1 wt% Molten glass stirring chamber, characterized in that it comprises a glass layer comprising to 2% by weight. 14. The method of claim 13,
The molten glass stirring chamber, characterized in that the seat portion protrudes so as to at least partially overlap the second body. delete 15. The method according to claim 13 or 14,
The lower portion of the first body is further provided with a noble metal cladding layer,
The molten glass stirring chamber, characterized in that the sheet portion is attached to the surface of the noble metal cladding layer. a stirred vessel configured to contain the molten glass;
a cover disposed on the top of the stirring vessel; and
a stirring body configured to agitate the molten glass through the cover;
including,
the cover comprises a noble metal cladding layer on at least its lower surface;
The surface of the noble metal cladding layer in the direction toward the molten glass is CaO 3 wt% (wt%) to 5 wt%, SiO ₂ 0.2 wt% to 1 wt%, Al ₂ O ₃ 0.2 wt% to 1 wt%, HfO ₂ Molten glass stirring chamber, characterized in that it is coated with a refractory oxide layer comprising 0.5 wt% to 3.5 wt% and the balance ZrO ₂ . 18. The method of claim 17,
The refractory oxide layer further comprises 0.01 wt% to 0.3 wt% of Fe ₂ O ₃ and 0.01 wt% to 0.9 wt% of MgO. 19. The method according to claim 17 or 18,
The molten glass stirring chamber, characterized in that the thickness of the refractory oxide layer is 2 mils to 8 mils. 18. The method of claim 17,
The cover has a central hole through which the stirring body passes and has a porous cover body divided into a first body and a second body along a boundary region extending through the central hole,
The first body and the second body are each covered with an inorganic layer, and the first body is provided with a sheet portion protruding in the horizontal direction along the boundary region. chamber.

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