KR20110102290A - Molten glass carrier facility element and glass production system - Google Patents

Abstract

Providing the molten glass conveying equipment element which has the ceramic structure in which the crack generate | occur | produced in the junction part of a vertical conduit and a horizontal conduit by thermal expansion at the time of heating, and shrinkage at the time of cooling is prevented.
A conduit structure for molten glass having a first conduit in a vertical direction and a second conduit in a horizontal direction in communication with the first conduit, wherein the first conduit and the second conduit are made of platinum or a platinum alloy; and the first conduit A molten glass conveying equipment element having a ceramic structure arranged around a conduit and the second conduit, wherein the ceramic structure contains at least 75 wt% of zirconium oxide and further has a proportion of cubic zirconia in the zirconium oxide. It is 80 wt% or more, the average open porosity of the said ceramic structure is 5 to 60%, and the linear thermal expansion coefficient in 20-1,000 degreeC of the said ceramic structure is 8 * 10 <^-6> -12 * 10 <^-6> / ^degreeC .

Description

MOLTEN GLASS CARRIER FACILITY ELEMENT AND GLASS PRODUCTION SYSTEM}

This invention relates to the glass manufacturing apparatus containing the molten glass conveyance equipment element which can be used suitably for glass manufacturing apparatuses, such as a vacuum degassing apparatus, and this molten glass conveyance equipment element.

In glass manufacturing apparatuses, such as a vacuum degassing apparatus, the component material of the conduit of molten glass is required to be excellent in heat resistance and corrosion resistance with respect to molten glass. Platinum or a platinum alloy is used as a material which satisfy | fills this (refer patent document 1). The heat insulation brick is arrange | positioned around the conduit of the molten glass of platinum or a platinum alloy so that the conduit may be enclosed.

Since the thermal expansion coefficients of the platinum or platinum alloy which comprise a conduit, and the thermal insulation brick arrange | positioned around the said conduit differ, the difference of the thermal expansion amount at the time of heating, and the shrinkage amount at the time of cooling become a problem.

In order to absorb the difference in the amount of thermal expansion during heating or the amount of shrinkage during cooling, an amorphous ceramic material such as castable cement is filled between the two so that the two move relatively relative to each other when a temperature change occurs.

Japanese Unexamined Patent Publication No. 2002-87826

However, the present inventors found that depending on the arrangement of the conduits of molten glass, the filling of the amorphous ceramic material may not be able to absorb the difference in the amount of thermal expansion during heating or the amount of shrinkage during cooling. .

1 is a cross-sectional view showing one configuration example of a vacuum degassing apparatus. In the vacuum degassing apparatus 100 shown in FIG. 1, the pressure reduction degassing tank 130 is arrange | positioned in the pressure reduction housing 120 so that the long axis may orientate in a horizontal direction. The rising pipe 140 is attached to the lower surface of one end of the pressure reduction degassing tank 130, and the descending pipe 150 is attached to the lower surface of the other end. In the pressure reduction housing 120, the heat insulating material 160 is arrange | positioned and formed in the circumference | surroundings of the pressure reduction degassing tank 130, the uprising pipe 140, and the downfalling pipe 150. As shown in FIG.

The riser 140 is connected to an upstream structure (not shown, for example, a glass melting tank) of the molten glass via the conduits 170, 180, and 190. The downcomer 150 is connected to a downstream structure (not shown. For example, a plate glass forming apparatus such as a float bath) via the conduits 200, 220, and 240. More specifically, the riser tube 140 having the central axis in the vertical direction includes a conduit 170 having the central axis in the horizontal direction, a conduit 180 having the central axis in the vertical direction, and a central axis in the horizontal direction. It is connected with the upstream structure via the conduit 190 which exists. Meanwhile, the downcomer 150 having a central axis in the vertical direction is a conduit 200 having a central axis in the horizontal direction, a conduit 220 having a central axis in the vertical direction, and a conduit 240 having a central axis in the horizontal direction. Is connected to the downstream structure via In addition, the riser 140, the downcomer 150, the conduits 170, 180, 190, 200, 220, and 240 are platinum or platinum alloy tubes.

Although not shown, a heat insulation brick is arrange | positioned so that the said platinum or platinum alloy pipe may be enclosed, and the amorphous ceramic material is filled between this platinum or platinum alloy pipe and the heat insulation brick.

In such a structure, platinum alone is used in the case of tubes 140, 150, 180, and 220 having a central axis in the vertical direction alone, or tubes 170, 190, 200, and 240 having a central axis in the horizontal direction alone. Alternatively, the difference in thermal expansion amount at the time of heating the platinum alloy tube and the heat insulating brick, or the difference in shrinkage amount at the time of cooling can be absorbed by the amorphous ceramic material filled therebetween. However, the joint of the pipe with the central axis in the vertical direction and the pipe with the central axis in the horizontal direction (joint of the ascending pipe 140 and the conduit 170, junction of the down pipe 150 and the conduit 200, conduit ( 170, the junction of conduit 180, the junction of conduit 180 and conduit 190, the junction of conduit 200 and conduit 220, and the junction of conduit 220 and conduit 240, are heated. The difference in thermal expansion amount at the time or the difference in shrinkage value at the time of cooling cannot be absorbed by the amorphous ceramic material, and there is a possibility that a crack occurs at the joint portion. When a crack generate | occur | produces in a junction part, there exists a problem that the heat insulation brick arrange | positioned around by the molten glass leaked from the crack erodes. Thereby, there exists a problem of the fall of productivity by a repair work, shortening of an equipment lifetime, etc.

In order to solve the above-mentioned problems of the prior art, the present invention relates to cracks at joints of conduits having a central axis in the vertical direction and conduits having a central axis in the horizontal direction by thermal expansion during heating or shrinkage during cooling. This generation is prevented, and for some reason, the molten glass conveying equipment element which has a ceramic structure which is hardly eroded even if a molten glass may leak may be provided, and the glass manufacturing apparatus containing this molten glass conveying equipment element is provided. It aims to do it.

In order to achieve the above object, the present invention has at least one first conduit having a central axis in a vertical direction and at least one second conduit having a central axis in a horizontal direction communicating with the first conduit. A conduit structure for molten glass, wherein the conduit and the second conduit are made of platinum or a platinum alloy;

As a molten glass conveying installation element which has a ceramic structure arrange | positioned around the said 1st conduit and a said 2nd conduit,

The ceramic structure contains 75 wt% or more of zirconium oxide in mass% of the total composition, and the ratio of cubic zirconia in the zirconium oxide is 80 wt% or more,

The average open porosity of the ceramic structure is 5 to 60%,

The linear thermal expansion coefficient in 20-1,000 degreeC of the said ceramic structure is 8 * 10 <^-6> -12 * 10 <^-6> / degreeC, The molten-glass conveyance equipment element is provided.

Moreover, this invention provides the glass manufacturing apparatus characterized by including the molten glass conveyance installation element of this invention.

In the molten glass conveying equipment element of the present invention, since the coefficient of thermal expansion of the conduit of the molten glass made of platinum or platinum alloy and the ceramic structure arranged around the conduit almost match, the amount of thermal expansion during heating or cooling The difference in shrinkage amount is very small. For this reason, cracks are prevented from occurring at the junction of the conduit with the central axis in the vertical direction and the conduit with the central axis in the horizontal direction due to thermal expansion during heating or shrinkage during cooling. Moreover, even if a molten glass may leak for some reason, the ceramic structure in this invention does not erode well.

In addition, it has been difficult to attain both crack prevention at the conduit junction due to thermal expansion upon heating or shrinkage upon cooling, and prevention of erosion of the ceramic structure due to leakage of the molten glass.

However, the glass manufacturing apparatus containing the molten glass conveyance installation element of this invention is prevented from the generation of the crack in a conduit junction part by thermal expansion at the time of heating, or shrinkage at the time of cooling, and for some reason. Since the ceramic structure does not erode well even if the molten glass may leak, the glass is excellent in reliability and can be stably manufactured for a long time.

1 is a cross-sectional view showing one configuration example of a vacuum degassing apparatus.
It is sectional drawing which shows one structural example of the molten-glass conveyance equipment element of this invention.
3 is a cross-sectional view of the test body used in Test Example 1. FIG.
4 is a perspective view showing the vicinity of the upper power feeding section 6 of FIGS. 3 and 5.
5 is a cross-sectional view of the test body used in Comparative Example 1. FIG.
6 is an explanatory diagram of an immersion test performed in Test Example 2. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated with reference to drawings.

2 is a cross-sectional view showing one configuration example of a molten glass conveying equipment element of the present invention. 2 corresponds to a partially enlarged view of the conduits 200, 220, and 240 in FIG. 1.

In the molten glass conveyance equipment element shown in FIG. 2, the conduit structure 1 for molten glass is a horizontal direction with respect to the 1st conduit (henceforth a "vertical pipe") 1a which has a central axis in a vertical direction. This structure is a structure in which two second conduits having a central axis (hereinafter referred to as "horizontal pipes") (1b) and other (1b) are in communication with each other.

The molten-glass conveyance equipment element in this invention should just have a vertical pipe and at least one horizontal pipe communicating with a vertical pipe, and are not limited to the aspect of illustration. For example, one horizontal pipe may communicate with one vertical pipe. In addition, one horizontal tube communicates with one vertical tube at one end thereof, and the horizontal tube communicates with another vertical tube at the other end thereof (conduit in FIG. 1). A structure corresponding to a combination of 150, 200, and 220), or one or more vertical tubes or horizontal tubes, or both thereof, in addition to such a structure (conduit 150 in FIG. 1). Or a structure corresponding to a combination of 200, 220, and 240).

In the vertical tube in the present invention, the central axis is not necessarily required to be in the vertical direction in a strict sense, and the central axis may be inclined with respect to the vertical direction. The same applies to the horizontal tube, and the central axis is not necessarily required to be horizontal in the exact sense, and the central axis may be inclined to some extent with respect to the horizontal direction. In other words, the vertical pipe and the horizontal pipe in the present invention are intended for their relative relationship, and when one of the conduits is a vertical pipe, the horizontal pipe is a horizontal pipe.

In addition, in consideration of the installation workability of the ceramic structure, the angle formed by the vertical tube and the horizontal tube in the joint portion of the vertical tube and the horizontal tube is preferably in the range of 90 ± 10 °.

In the present invention, since the first conduit and the second conduit are used as conduits of the molten glass, the constituent material is required to be excellent in heat resistance and corrosion resistance to the molten glass. For this reason, the first conduit and the second conduit consist of platinum or platinum alloys such as platinum-gold alloys, platinum-rhodium alloys, platinum-iridium alloys.

The platinum or platinum alloy constituting the first conduit and the second conduit, it is made of platinum or platinum alloy Al ₂ O _3, a reinforced platinum formed by dispersing the metal oxide particles, such as ZrO _2, or Y ₂ O ₃ is preferred. Content of these metal oxide particles is 0.1-0.5 mass% with respect to a platinum alloy (100 mass%), Preferably it is 0.15-0.4 mass%.

In reinforced platinum, metal oxide particles dispersed in platinum or platinum alloys have an effect of inhibiting dislocations and growth of crystal grains, thereby increasing mechanical strength. However, on the other hand, since the ductility of the material is lowered as compared with the conventional platinum or platinum alloy, the difference in thermal expansion amount at the time of heating with the heat insulation brick disposed around the tube at the junction of the vertical tube and the horizontal tube, Alternatively, the difference in shrinkage at the time of cooling cannot be absorbed by the elongation of the tube material, and cracks are likely to occur at the joints. For this reason, it is preferable to apply this invention which hardly produces the said thermal expansion difference of the said platinum or platinum alloy and the said ceramic structure which generate | occur | produce by thermal expansion at the time of heating or shrinkage at the time of cooling.

In FIG. 2, the ceramic structure 2 is arrange | positioned around the 1st conduit 1a and the 2nd conduit 1b.

The ceramic structure 2 in the present invention contains 75 wt% or more of zirconium oxide in mass% of the total composition, and the proportion of cubic zirconia occupied by zirconium oxide is 80 wt% or more. In other words, this invention uses what consists of cubic zirconia which is a fully stabilized zirconia mainly as a heat insulation brick arrange | positioned around a 1st conduit and a 2nd conduit.

By mainly using cubic zirconia, the amount of thermal expansion at the time of heating or the amount of shrinkage at the time of cooling becomes substantially the same in the first conduit and the second conduit and the ceramic structure arranged around them. As a result, the difference between the amount of thermal expansion at the time of heating or the amount of shrinkage at the time of cooling becomes very small, and cracks are prevented from occurring at the junction between the vertical pipe and the horizontal pipe due to thermal expansion at the time of heating or shrinkage at the time of cooling.

As shown below, cubic zirconia, which is fully stabilized zirconia, has a coefficient of thermal expansion very close to that of the platinum or platinum alloy constituting the conduit at 20 to 1,000 ° C., so that cracking can be prevented at the junction. .

Coefficient of thermal expansion of platinum and platinum alloy: 9.5 × 10 ⁻⁶ / ° C. to 11 × 10 ⁻⁶ / ° C., and coefficient of linear expansion of cubic zirconia: 8.5 × 10 ⁻⁶ / ° C. to 10.5 × 10 ⁻⁶ / ° C.

Furthermore, zirconium oxide such as cubic zirconia is excellent in heat resistance, corrosion resistance of molten glass, corrosion resistance to corrosive gas, and the like, and is preferable as a heat insulating brick disposed around the first conduit and the second conduit, which are conduits of molten glass. .

In order to exhibit the said effect, the linear thermal expansion coefficient in 20-1000 degreeC of a ceramic structure is 8 * 10 <^-6> -12 * 10 <^-6> / degreeC, and 9 * 10 <^{-6> -11} * 10 <^-6> / degreeC It is preferable that it is and it is more preferable that it is 9.5 * 10 <^-6> -10.5 * 10 <^-6> / ^degreeC .

However, since the coefficient of thermal expansion of the platinum or platinum alloy is slightly different depending on the composition, it is preferable to select the coefficient of thermal expansion of the ceramic structure according to the coefficient of thermal expansion of the platinum or platinum alloy used in the first conduit and the second conduit. . Specifically, the coefficient of linear thermal expansion at 20 to 1,000 ° C. of the ceramic structure is within ± 15% of the coefficient of linear thermal expansion at 20 to 1,000 ° C. of the platinum or platinum alloy constituting the first and second conduits. It is preferable, it is more preferable that it is within ± 10%, and it is still more preferable that it is within ± 5%.

In order to achieve said linear thermal expansion coefficient, the zirconium oxide contained in a ceramic structure is 75 wt% or more, and it is necessary to make the ratio of the cubic zirconia occupied therein to 80 wt% or more. It is preferable that the ratio of cubic zirconia to zirconium oxide contained in a ceramic structure is 85 wt% or more, and it is more preferable that it is 90 wt% or more.

The ceramic structure 2 of the present invention is a remainder from which zirconium oxide is removed, and contains a stabilizer added in order to turn zirconium oxide into cubic zirconia which is stabilized zirconia. As the remainder, inevitable impurities and the like may be contained. In addition, as long as it does not affect this invention, you may contain other components other than zirconium oxide and a stabilizer in the ceramic structure 2 of this invention to about 8 wt% in total. The other components such as, for example, may be mentioned Al ₂ O ₃ or MgO to be added in order to improve the sinterability, which may contain up to about 5 wt% in total.

Stabilizers include yttrium oxide, cerium oxide, magnesium oxide, calcium oxide, erbium oxide, and the like, which are excellent in corrosion resistance to molten glass, easy to obtain, and stable even if maintained at high temperature for a long time. Cerium is preferred.

When it contains at least one selected from the group consisting of yttrium oxide and cerium oxide as a stabilizer, the total content of both is preferably 6 wt% or more, more preferably 8 wt% or more, and even more preferably 10 wt% or more. Do.

However, when the addition amount of a stabilizer is too large, there exists a problem that sintering is difficult and raw material cost rises. For this reason, it is preferable that it is 25 weight% or less, and, as for the sum total content of both, it is more preferable that it is 20 weight% or less.

Although content of zirconium oxide in a ceramic structure changes with addition amount of a stabilizer, in order to make a linear thermal expansion coefficient into a predetermined range, it is 75 weight% or more, It is preferable that it is 80 weight% or more, It is more preferable that it is 85 weight% or more desirable. On the other hand, in the balance with the addition amount of a stabilizer, content of zirconium oxide in a ceramic structure becomes an upper limit about 94 wt%.

In the ceramic structure of the present invention, the average open porosity is 5 to 60%. Although the ceramic structure of this invention is excellent in corrosion resistance with respect to a molten glass, when the average open porosity is more than 60%, corrosion resistance with respect to a molten glass falls. On the other hand, when the average open porosity is less than 5%, the thermal shock resistance of the ceramic structure is lowered. In addition, since the heat capacity increases, a deviation occurs between the thermal expansion during heating or the contraction timing during cooling between the first conduit 1a and the second conduit 1b and the ceramic structure 2 made of platinum or platinum alloy. It becomes easy to do it, and there exists a possibility that a crack may generate | occur | produce in the junction part of the 1st conduit 1a which is a vertical pipe, and the 2nd conduit 1b which is a horizontal pipe. Moreover, the time required for heating or cooling also becomes long.

It is preferable that the average open porosity of the ceramic structure of this invention is 25 to 60%, It is more preferable that it is 30 to 50%, It is especially preferable that it is 35 to 45%.

However, when the average porosity is high, a point occurs at which heat from the conduit is hardly transferred to the inside of the ceramic structure, and thermal expansion of the ceramic structure is partially prevented, and a part of the conduit may be loaded. Therefore, when the load is not applied to the conduit or when the corrosion resistance is further improved, the average open porosity of the ceramic structure is preferably 5 to 35%, more preferably 8 to 30%, more preferably 10 to 25 It is especially preferable that it is%.

The average open porosity of the ceramic structure can be obtained by measurement by the Archimedes method or a mercury porosimeter.

In the ceramic structure of the present invention, the open porosity may be different depending on the site. For example, the corrosion resistance with respect to a molten glass can be improved by making the area | region which faces a 1st conduit and a 2nd conduit lower than another site | part.

In FIG. 2, a gap 3 is formed between the first conduit 1a and the second conduit 1b and the ceramic structure 2.

As described above, in the present invention, the amount of thermal expansion at the time of heating or the amount of shrinkage at the time of cooling in the first conduit 1a and the second conduit 1b and the ceramic structure 2 disposed around them Almost the same. However, since the platinum or platinum alloy which comprises the 1st conduit 1a and the 2nd conduit 1b, and the zirconium oxide which comprises the ceramic structure 2 differ in thermal conductivity, depending on heating conditions or cooling conditions, In some cases, there may be a deviation between the thermal expansion at the time of heating or the shrinkage timing at the time of cooling, and a crack may occur at the junction between the first conduit 1a, which is a vertical pipe, and the second conduit 1b, which is a horizontal pipe.

By forming the gap 3 between the first conduit 1a and the second conduit 1b and the ceramic structure 2, it is possible to absorb the deviation of the thermal expansion during heating or the contraction timing during cooling between the two conduits. Therefore, cracks can be prevented from occurring at the junction.

In addition, in this invention, since the amount of thermal expansion at the time of heating, or the amount of shrinkage at the time of cooling becomes substantially the same in the 1st conduit 1a and the 2nd conduit 1b, and the ceramic structure 2 arrange | positioned around them, It is not necessary to fill the gap 3 with an amorphous ceramic material.

The width d of the gap 3 is preferably 0.5 mm or more and 0.02 x r (mm) or less when the maximum diameters of the first conduit 1a and the second conduit 1b are r (mm). When the width | variety d of the clearance gap 3 is less than 0.5 mm, there exists a possibility that it may not fully absorb the shift | offset | difference of the thermal expansion at the time of heating, or the contraction timing at the time of cooling. On the other hand, when the width d of the gap 3 is larger than 0.02 x r (mm), a large gap remains between both after expansion, and the first conduit 1a and the second conduit 1b are made of molten glass passing through the interior. ) Is deformed.

Moreover, it is preferable that the said largest diameter r is 60 mm or more. This is because when the maximum diameter r is 60 mm or more, securing the rigidity of the conduit becomes difficult, and therefore, the effect of the present invention (prevention of cracking at the welded portion) is exerted and is preferable.

In addition, although the said largest diameter r may differ according to the site | part which these conduits are used, the rising pipe 140 and the falling pipe 150 shown in FIG. 1, and the conduits 170, 180, 190, 200 connected to these, are shown. , 220 or 240), it is usually 120 to 400 mm.

It is more preferable that it is 1-3 mm, and, as for the width | variety d (mm) of the clearance gap 3, it is still more preferable that it is 1.5-2.5 mm.

Since cubic zirconia is an expensive material, it is preferable in terms of cost that the ceramic structure arranged around the first conduit and the second conduit is minimized as necessary. Specifically, it is preferable to arrange the ceramic structure (hereinafter also referred to as "first ceramic structure"), and to arrange an ordinary heat insulating brick as a second ceramic structure on the outside thereof. In this case, as a 2nd ceramic structure, the heat insulation brick which mainly has at least 1 chosen from the group which consists of alumina, magnesia, zircon, and silica can be used.

As a specific example of the heat insulation brick used as a 2nd ceramic structure, a silica alumina heat insulation brick, a zirconia heat insulation brick, a magnesia heat insulation brick, etc. are mentioned. As a commercial item, SP-15 (made by the Hinomaru ceramics company), LBK3000 (made by the isolite industry company), etc. are mentioned.

When arrange | positioning a 2nd ceramic structure outside the 1st ceramic structure, it is preferable that the thickness of a 1st ceramic structure is 15 mm or more. If the thickness of the first ceramic structure is less than 15 mm, since the amount of thermal expansion during heating or shrinkage during cooling of the first ceramic structure is hindered by the second ceramic structure, the first conduit and the second conduit and the surroundings thereof The difference between the amount of thermal expansion during heating or the amount of shrinkage during cooling between the ceramic structures arranged is large, and cracks are likely to occur at the junction between the first conduit and the second conduit.

On the other hand, when the maximum diameters of the first conduit 1a and the second conduit 1b are r (mm), the thickness of the first ceramic structure is 0.3 × r (mm) or less. It is preferable for reasons.

As for the thickness of a 1st ceramic structure, it is more preferable that it is 15-120 mm, and it is still more preferable that it is 30-80 mm.

The glass manufacturing apparatus of this invention uses the molten glass conveyance equipment element of this invention as at least one part of the flow path of molten glass. As an example of the glass manufacturing apparatus of this invention, the pressure reduction defoaming apparatus using the molten glass conveyance equipment element of this invention is mentioned as at least one part of the flow path of molten glass. When the vacuum degassing apparatus shown in FIG. 1 is the glass manufacturing apparatus of this invention, as at least one part of the combination which consists of the riser 140, the conduits 170, 180, and 190, or the downcomer 150, the conduit 200 The molten glass conveying equipment element of this invention is included as at least one part of the combination which consists of 220, and 240, or both.

The glass manufacturing apparatus of this invention will not be specifically limited if it uses the molten glass conveyance equipment element of this invention as at least one part of the flow path of molten glass, and it is an upstream glass melting tank and a downstream plate glass forming apparatus (for example, a float bath) ) May be included.

Example

Hereinafter, although the Example of this invention demonstrates in detail, it limits to these and is not interpreted.

(Test Example 1)

3 is a cross-sectional view of the test body used in Test Example 1. FIG. In the test example 1, the hollow tube (in the state which arrange | positioned the ceramic structure 2 around the reinforcement platinum hollow tube 1c, and arrange | positioned the 2nd ceramic structure 4 around the ceramic structure 2) By energizing and heating 1c), the presence or absence of the deformation and the crack in the hollow tube 1c were evaluated.

As the hollow tube 1c, 0.16 mass% of ZrO ₂ particles were dispersed in a reinforced platinum (platinum-rhodium alloy (90 mass% of platinum, 10 mass% of rhodium)) having an outer diameter of 60 mm, a length of 300 mm, and a thickness of 0.5 mm. 20 A hollow tube made of a linear thermal expansion coefficient of 10.3 × 10 ⁻⁶ / ° C.) at ^˜1,000 ° C. was used. A flange 5 having a width of 15 mm and a thickness of 1.2 mm was fixed at a position of 200 mm from one end of the hollow tube 1c by TIG (tungsten inert gas) welding. Moreover, as shown in FIG. 4, the electricity supply heating part 6 for electricity supply heating was welded to the upper end of the hollow tube 1c.

Although not shown in FIG. 4, the electric power feeding part 6 for energization heating was welded also to the lower end of the hollow tube 1c. In addition, the flange 5 and the power supply portion 6 is strengthened platinum-a (platinum-rhodium alloy (90 mass% platinum, to which 0.16 mass% of ZrO ₂ particles dispersed in rhodium-10% by mass)).

The ceramic structure 2 disposed around the hollow tube 1c is a zirconium oxide in which 12% by mass of yttrium oxide is added to the total amount of zirconium oxide and yttrium oxide as a stabilizer, and the content of zirconium oxide is 87 wt%. The ratio of the cubic zirconia to zirconium oxide is 95 wt%, and the inner diameter × outer diameter × length = 61 mm × 150 mm × 300 mm of hollow cylindrical shape (assembled by dividing semi-cylindrical shape divided into two directions ), The coefficient of linear thermal expansion at 20 to 1,000 ° C is 9.8 × 10 ⁻⁶ / ° C. In addition, about the average porosity of the ceramic structure 2, it tested about two types of about 8% and about 40%. In addition, a 0.5 mm gap was formed between the hollow tube 1c and the ceramic structure 2.

In addition, as shown in FIG. 3, the ceramic structure 2 is in a state placed between the two power feeding parts 6, and the lower end side of the ceramic structure 2 is mechanically fixed to the power feeding part 6. (Not shown).

On the outside of the ceramic structure 2, a commercially available silica alumina heat insulating brick (SP-15 (manufactured by Hinomaru Co., Ltd.)) was disposed as the second ceramic structure 4.

The test body was made to tightly tighten the circumference | surroundings of the 2nd ceramic structure 4 by the metal frame material.

Energizing and heating the hollow tube 1c using the feeder 6, and cooling the hollow tube 1c while controlling the temperature by a thermocouple (not shown) disposed near the flange 5. The temperature cycle test was repeated which repeats. Moreover, after heating at the temperature increase rate of 200 degreeC / hour, it hold | maintained at 1400 degreeC for 3 hours, and after that, naturally cooling to 200 degreeC was repeated 20 times. In the temperature cycle test, the expansion and contraction in the axial direction of the hollow tube 1c and the ceramic structure 2 is carried out at the lower end side which is mechanically fixed to the feed section 6, and the portion at which the flange 5 is formed. Except to be free to exit.

After the temperature cycle test, the test body was dismantled and the state of the hollow tube 1c was confirmed. In the case of the ceramic structures of the two kinds of average porosity, no deformation or crack of the hollow tube 1c was observed. However, in the case of the ceramic structure with an average porosity of about 40%, arc-shaped wrinkles were observed in a part directly under the welded portion of the flange 5. In addition, in the case of the ceramic structures of the above two kinds of average porosity arranged around the hollow tube 1c, the appearance was almost unchanged. Therefore, when the average porosity is 5 to 35%, heat is particularly easily transferred from the conduit to the interior of the ceramic structure, thereby preventing the load on the conduit.

(Comparative Example 1)

5 is a cross-sectional view of the test body used in Comparative Example 1. FIG. In the test body used in Comparative Example 1, instead of arranging the ceramic structure 2 around the hollow tube 1c, a commercially available product was used as the second ceramic structure 4 in Test Example 1 around the hollow tube 1c. A silica-alumina insulating brick (SP-15 (manufactured by Hinomaru Co., Ltd.)) was formed to form a gap 3 of about 30 mm, and then the kneaded mixture of alumina mortar of hollow particles with water was gap. The temperature cycle test was carried out in the same procedure as in Test Example 1, except that it was filled without, to form a layer of amorphous ceramic material.

After the temperature cycle test, the test body was disassembled and the state of the hollow tube 1c was confirmed, but a minute crack occurred in the welded portion of the flange 5 of the hollow tube 1c. Moreover, the alumina mortar layer arrange | positioned around the hollow tube 1c was divided into several pieces, as if it had cracked after it solidified.

(Test Example 2)

Using the same material as the ceramic structure 2 of Test Example 1, three test samples (shape: cylindrical shape (diameter 20 mm, height 90 mm)) having an average porosity of 8%, 33% and 54% were produced. . As shown in FIG. 6, this test sample 10 was immersed in the molten glass 30 (borosilicate glass) put in the platinum crucible 20 in air | atmosphere. At this time, the maximum temperature of the molten glass was 1450 degreeC, and the immersion time of the test sample 10 was 100 hours. After the end of the holding time, the test sample 10 was taken out and left to naturally cool. Then, the test sample was cut longitudinally and the cross-sectional state was confirmed. In all test samples, glass did not penetrate to the inside, and corrosion resistance was ensured and the initial shape was maintained. However, in the test sample whose average porosity is 54%, glass intruded into a part of outer peripheral part, and peeling was observed in a part of ceramic surface. Therefore, corrosion resistance will especially improve that average porosity is 5 to 35%.

(Comparative Example 2)

Commercially available silica alumina heat insulating bricks (SP-15 (manufactured by Hinomaru Co., Ltd.)) used as the second ceramic structure 4 in Test Example 1 were immersed in the molten glass in the same order. The erosion brick completely collapsed by erosion, and the cross-sectional state could not be observed.

(Application Example 1)

In the vacuum degassing apparatus shown in FIG. 1, the combination which consists of the rising pipe 140, the conduits 170, 180, and 190, and the combination which consists of the falling pipe 150 and the conduits 200, 220, 240 are shown. It comprises as a molten-glass conveyance equipment element of this invention.

0.16 mass% of ZrO ₂ particles dispersed in a reinforcing platinum agent (platinum-rhodium alloy (90% by mass of platinum, 10% by mass of rhodium). Linear thermal expansion coefficient of 10.3 × 10 ⁻⁶ / ° C. at 20 to 1,000 ° C.) A first mainly composed of cubic zirconia around the riser 140, the downcomer 150, the conduits 170, 180, 190, 200, 220, and 240 (cross-sectional shape: circular, outer diameter: 180 mm) Ceramic structure (The ratio of zirconium oxide to the total composition is 88 wt%, the ratio of cubic zirconia to zirconium oxide is 95 wt%, and 12 wt% of yttrium oxide as a stabilizer, and the average porosity is 12 % Or 35%, and the coefficient of linear thermal expansion at 20 to 1,000 ° C. is 9.8 × 10 ⁻⁶ / ° C. The thickness is 45 mm), with a gap of 1.5 mm between the tubes.

Outside the first ceramic structure, a silica alumina insulating brick is disposed as the second ceramic structure.

The glass bath is manufactured by arrange | positioning a dissolution tank in the upstream of the vacuum degassing apparatus shown in FIG. 1, and a float bath downstream. Cracks do not occur at the junction of each vertical tube and horizontal tube, and glass can be stably manufactured.

Industrial availability

As for the glass manufacturing apparatus containing the molten glass conveyance installation element of this invention, the crack in a conduit joining part is prevented from occurring by the thermal expansion at the time of heating, or shrinkage at the time of cooling, and the molten glass may leak. Even if the ceramic structure is not eroded well, the ceramic structure is excellent in reliability and industrially useful for producing glass stably over a long period of time.

In addition, all the content of the JP Patent application 2008-315710, a claim, drawing, and the abstract for which it applied on December 11, 2008 is referred here, and it introduces as an indication of the specification of this invention.

1: molten glass conveying equipment element
1a: first conduit (vertical pipe)
1b: second conduit (horizontal pipe)
1c: hollow tube
2: ceramic structure
3: gap
4: second ceramic structure
5: flange
6: feeder
10: test sample
20: crucible
30: molten glass
100: vacuum degassing apparatus
120: pressure reducing housing
130: vacuum degassing tank
140: riser
150: down pipe
160: insulation
Conduits: 170, 180, 190, 200, 220, 240

Claims (8)

At least one first conduit with a central axis in the vertical direction and at least one second conduit with a central axis in the horizontal direction in communication with the first conduit, the first conduit and the second conduit being of platinum or platinum alloy; A conduit structure for molten glass,
As a molten glass conveying installation element which has a ceramic structure arrange | positioned around the said 1st conduit and a said 2nd conduit,
The ceramic structure contains 75 wt% or more of zirconium oxide in mass% of the total composition, and the ratio of cubic zirconia in the zirconium oxide is 80 wt% or more,
The average open porosity of the ceramic structure is 5 to 60%,
The linear thermal expansion coefficient in 20-1,000 degreeC of the said ceramic structure is 8 * 10 <^-6> -12 * 10 <^-6> / degreeC, The molten-glass conveyance equipment element characterized by the above-mentioned. The coefficient of linear thermal expansion at 20 to 1,000 캜 of the platinum or platinum alloy constituting the first conduit and the second conduit according to claim 1, wherein the coefficient of linear thermal expansion at 20 to 1,000 캜 of the ceramic structure. Molten glass conveying equipment element within ± 15%. The molten glass conveying equipment element according to claim 1 or 2, wherein the ceramic structure contains 6 to 25 wt% of at least one selected from the group consisting of yttrium oxide and cerium oxide as a stabilizer. The molten glass conveying equipment element according to any one of claims 1 to 3, wherein the platinum or platinum alloy constituting the first conduit and the second conduit is reinforced platinum in which a metal oxide is dispersed in the platinum or platinum alloy. . The maximum diameter of the first conduit and the second conduit according to any one of claims 1 to 4, wherein r (mm) (where r

60 mm), The molten glass conveyance equipment element in which the clearance gap of 0.5 mm or more and 0.02 * r (mm) or less is formed between the said 1st conduit, the said 2nd conduit, and the said ceramic structure. The maximum diameter of the first conduit and the second conduit according to any one of claims 1 to 5, wherein r (mm) (where r

60 mm), The molten glass conveyance equipment element whose thickness of the said ceramic structure is 15 mm or more and 0.3 * r (mm) or less. The molten glass conveyance installation element of Claim 6 in which the 2nd ceramic structure mainly having at least 1 selected from the group which consists of alumina, magnesia, zircon, and a silica is arrange | positioned outside the said ceramic structure. The molten glass conveyance installation element of any one of Claims 1-7 is included, The glass manufacturing apparatus characterized by the above-mentioned.

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