JP3724156B2 - Parallel vacuum deaerator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of a vacuum degassing apparatus for molten glass that removes bubbles from continuously supplied molten glass.
[0002]
[Prior art]
Conventionally, in order to improve the quality of a molded glass product, a vacuum degassing apparatus that removes bubbles generated in the molten glass before the molten glass melted in the melting furnace is molded by a molding apparatus has been used. . Such a conventional vacuum degassing apparatus is shown in FIG. The vacuum degassing apparatus 100 shown in FIG. 4 depressurizes the molten glass G in the melting tank 102 under reduced pressure to form a next processing tank (not shown) such as a processing tank for a plate material such as a float bath or a working tank such as a bottle. Used in a continuous supply process, a vacuum degassing tank 106 is horizontally accommodated in a vacuum suction housing 104 that is sucked in vacuum, and a riser pipe 108 and a downfall pipe 110 that are vertically attached to both ends thereof are accommodated. Has been.
[0003]
The ascending pipe 108 communicates with the vacuum degassing tank 106 to raise the molten glass G before the defoaming treatment from the melting tank 102 and introduce it into the vacuum degassing tank 106. The downcomer 110 communicates with the reduced-pressure defoaming tank 106, lowers the molten glass G after the defoaming process from the reduced-pressure defoaming tank 106, and guides it to the next processing tank (not shown). In the reduced pressure housing 104, a heat insulating material 112 such as a heat insulating brick is provided around the reduced pressure defoaming tank 106, the ascending pipe 108, and the descending pipe 110 so as to cover them. The decompression housing 104 is made of metal, for example, stainless steel, and is vacuumed from the outside by a vacuum pump (not shown) or the like, the inside is decompressed, and the inside of the decompression deaeration tank 106 is set to a predetermined decompression. For example, the pressure is maintained at a reduced pressure of 1/20 to 1/3 atm.
[0004]
Since the conventional vacuum degassing apparatus 100 is configured to process a molten glass G at a high temperature, for example, 1200 to 1400 ° C., it is disclosed in Japanese Patent Application Laid-Open No. 2-221129 relating to the application of the present applicant. As shown in the drawing, the portions that are in direct contact with the molten glass G, such as the vacuum degassing tank 106, the rising pipe 108, and the downfalling pipe 110, are usually made of noble metal such as platinum, platinum rhodium, or platinum alloy such as platinum palladium. It consists of a circular tube. The present applicant has put a vacuum degassing apparatus into practical use by using a platinum alloy circular tube.
Here, these are constituted by noble metal circular tubes such as platinum alloys because not only the molten glass G is hot, but also the noble metal has low high temperature reactivity with the molten glass and is inhomogeneous due to reaction with the molten glass. This is because the strength at a high temperature can be secured to some extent without causing any deterioration.
In particular, the vacuum defoaming tank 106 is composed of a noble metal circular tube, in addition to the above reasons, a current is passed through the noble metal circular tube itself to cause self-heating to uniformly heat and melt the molten glass G in the cylinder. This is to keep the temperature of the glass G at a predetermined temperature.
[0005]
[Problems to be solved by the invention]
By the way, when the vacuum degassing tank 106 is made of a noble metal, it is preferable to use a circular tube from the viewpoint of high temperature strength. However, since noble metals such as platinum are expensive, the thickness cannot be increased . Therefore, there is a limit to the diameter of the circular tube in terms of both cost and strength, the diameter of the circular tube cannot be increased so much, and the flow rate of the molten glass G that can be defoamed in the vacuum degassing tank 106 is also limited. There was a problem that it was not possible to construct a vacuum degassing apparatus with a large flow rate. Of course, it is conceivable to increase the amount of defoaming by increasing the overall length of the tubular vacuum degassing tank 106 and increasing the flow rate. Compared to the above, there is a problem that the apparatus becomes longer. For this reason, there also existed a problem that the defoaming processing amount (flow rate) of the molten glass G in the vacuum degassing apparatus 100 could not be enlarged.
[0006]
In addition, when only one vacuum degassing apparatus having a small amount of defoaming treatment (flow rate) is used as described above, the flow rate of the molten glass G is also set in accordance with the amount to be produced. There is a problem that the range of possible flow rate is narrow and therefore it is difficult to respond flexibly to fluctuations in production volume.
Furthermore, in the event of an emergency, such as when platinum or a platinum alloy constituting the reduced pressure defoaming tank 106, the rising pipe 108, the downfalling pipe 110, etc. is damaged, the repair takes several months, and during that time, the reduced pressure defoaming apparatus There is also a problem in that the glass cannot be used, and the production of glass products is hindered.
[0007]
An object of the present invention is to solve the problems of the prior art, and to process a large amount of molten glass in a vacuum degassing apparatus for molten glass that removes bubbles from continuously supplied molten glass. An object of the present invention is to provide a parallel-type vacuum degassing apparatus that can obtain a molten glass excellent in homogeneity while being able to flexibly cope with fluctuations in production volume.
[0008]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention includes two vacuum degassing parts for performing vacuum degassing of molten glass supplied from a melting tank, and molten glass supplied from the two vacuum degassing parts. And the two vacuum degassing parts are provided in a vacuum housing that is vacuum-sucked, and in the vacuum housing, respectively. A vacuum defoaming tank for foaming, an introduction means that is provided in communication with the vacuum degassing tank and that introduces molten glass before the degassing defoaming supplied from the melting tank into the vacuum degassing tank; A degassing unit that is provided in communication with the defoaming tank and leads the molten glass after depressurization defoaming from the depressurization defoaming tank to the merging section; and further, the two depressurization units communicate with each other. Provided is a parallel-type vacuum degassing apparatus characterized by having a pressure equalizing pipe .
[0009]
Here, the introduction means is a riser pipe that raises the molten glass before vacuum degassing and introduces it into the vacuum degassing tank, and the derivation means sends the molten glass after vacuum degassing to the vacuum degassing tank. It is preferable that it is a downcomer pipe that descends from the outlet and leads out to the junction.
The merging section includes two storage tanks that communicate with the two derivation means, a merging tank that is provided so as to communicate with both of the two storage tanks via a throat, and a downstream of the merging tank. And a stirring device provided in communication with the side.
[0010]
Moreover, it is preferable that the pressure equalizing pipe is provided with a cock for blocking communication between the vacuum degassing tanks of the two vacuum degassing parts.
The molten glass is preferably soda lime glass.
Furthermore, it is preferable that at least a main portion of the introduction unit, the vacuum degassing tank, and the lead-out unit that are in direct contact with the molten glass is formed of an electroformed refractory.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the parallel vacuum degassing apparatus of the present invention will be described in detail based on the preferred embodiments shown in the accompanying drawings.
[0012]
In FIG. 1, the schematic sectional drawing of the parallel-type vacuum degassing apparatus of this invention is shown.
As shown in FIG. 1, the parallel-type vacuum degassing apparatus 10 (hereinafter referred to as the vacuum degassing apparatus 10) performs a vacuum degassing process on the molten glass G in the melting tank 20, and a next processing tank (not shown), For example, it is used in a process for continuously supplying a plate material such as a float bath to a forming processing tank such as a bottle or a forming work tank such as a bottle. The first vacuum degassing unit 11, the second vacuum degassing unit 12, The pressure tube 42 and the merging portion 50 are configured.
In addition, since the 1st vacuum degassing part 11 and the 2nd vacuum degassing part 12 are comprised similarly to each other, hereafter, the 1st vacuum degassing part 11 is mainly demonstrated and about the 2nd vacuum degassing part 12 below. The explanation is basically omitted.
[0013]
FIG. 2 shows a schematic cross-sectional view of the first vacuum degassing unit 11 and the merging unit 50 of the parallel-type vacuum degassing apparatus 10 shown in FIG.
The first vacuum degassing unit 11 includes a vacuum housing 11 a, a vacuum degassing tank 14, an ascending pipe 16, and a descending pipe 18.
The decompression housing 11a is for ensuring the airtightness of the decompression defoaming tank 14, and is formed in a substantially gate shape. The material and structure of the decompression housing 11a is not particularly limited as long as it has the airtightness and strength required for the decompression defoaming tank 14, but is made of metal, particularly stainless steel. Is preferred. Such a decompression housing 11a is vacuum-sucked by a vacuum pump (not shown) or the like from the outside, the inside is decompressed, and a predetermined decompression, for example 1/20 / It is configured to maintain a reduced pressure of 3 atm.
[0014]
A vacuum degassing tank 14 is provided in the upper part of the vacuum housing 11a. A rising pipe 16 communicates with the left end of the vacuum degassing tank 14, and a down pipe 18 communicates with the right end of the vacuum degassing tank 14. The ascending pipe 16 and the descending pipe 18 are respectively disposed in the legs of the decompression housing 11a. However, the descending pipe 18 communicates with a junction 50 described later together with the descending pipe 19 of the second decompression defoaming part 12. As is possible, it is configured to be inclined or refracted midway.
[0015]
In the vacuum degassing apparatus 10 of the present invention, the materials of the vacuum degassing tank 14, the rising pipe 16 and the descending pipe 18 are not particularly limited, and platinum, platinum rhodium, platinum alloys such as platinum palladium and the like, Examples include cast refractories, among which electrocast refractories are preferably used. That is, by forming the main part in direct contact with the molten glass G in the vacuum degassing apparatus 10 with an electroformed refractory, the cost is significantly reduced as compared with those made of noble metal alloys conventionally used. Since it is possible to design in a free shape and a free thickness, it is possible to increase the capacity of the vacuum degassing apparatus 10 and to perform vacuum degassing at a higher temperature. It is.
[0016]
There are no particular limitations on the shape of the vacuum degassing tank 14, the ascending pipe 16, and the descending pipe 18, as long as they are at least cylindrical. For example, the cross-sectional shape may be not only circular but also square. When constructing the vacuum degassing tank 14, the rising pipe 16, and the downfalling pipe 18 using the electroformed refractory, the method is not particularly limited. For example, small rectangular parallelepiped electrocast bricks are stacked, and a portion of the joint between them. A cylindrical tube of a predetermined length may be formed by filling the joint material with a joint material, or cylindrical electroformed bricks cast into a cylindrical shape or a rectangular tube shape are stacked in a row, and the joint portion between them is jointed. A cylindrical tube having a predetermined length may be formed by filling with a material.
[0017]
In addition, about the part immersed in the molten glass G in the upstream pit 20 at the lower end of the riser pipe 16 and the lower part of the downcomer pipe 18 and the part immersed in the molten glass G in the furnace material partition wall 52 described later. In particular, since there is an interface between the molten glass G and the atmosphere, the vicinity of this interface is rich in reactivity, and it cannot be used with fired bricks. Deterioration of the part tends to progress. Therefore, it is preferable that the lower end portion of the rising pipe 16 and the lower end portion of the down pipe 18 are made of platinum or a platinum alloy.
[0018]
The electrocast refractory is not particularly limited as long as the refractory raw material is electrically melted and then cast into a predetermined shape, and various conventionally known electrocast refractories may be used. Among these, alumina-based electrocast refractories, zirconia-based electrocast refractories, AZS-based electrocast refractories and the like are preferable examples because they have high corrosion resistance and little foaming from the substrate. Specifically, marsnite (MB-G), ZB-X950, zirconite (ZB) (all manufactured by Asahi Glass Co., Ltd.) and the like.
[0019]
A heat insulating brick 32 (hereinafter referred to as a heat insulating brick 32) covering the vacuum defoaming tank 14 is disposed around the vacuum degassing tank 14, and the rise pipe 16 and the down pipe 18 are respectively surrounded by the bricks. A heat insulating brick 32 is disposed to cover the surface.
As the heat insulating brick 32, known various bricks may be used and are not particularly limited. The heat-insulating bricks 32 arranged in this way are accommodated in the decompression housing 11a by covering the outside with the decompression housing 11a. The temperature outside the decompression housing 11a should be as low as possible, for example, about 100 ° C., by blocking the heat transmitted to the decompression housing 11a by the heat insulating brick 32 as much as possible in order to avoid high temperature creep of the decompression housing material. preferable.
[0020]
Moreover, it is good also as a structure which can provide a heating heater with the heat insulation brick 32 around the decompression degassing tank 14, the riser pipe 16, and the downfall pipe 18 as needed, and it can let cooling water pass through. It is good also as a structure which can be cooled.
[0021]
Here, since the vacuum degassing apparatus 10 of the present invention is a parallel type having the first vacuum degassing part 11 and the second vacuum degassing part 12, the melt that has passed through these vacuum degassing parts 11 and 12 is used. By adopting a configuration in which the glass G is merged by the merging unit 50, it is possible to perform a vacuum defoaming treatment of a large amount of molten glass, and for example, only one of the vacuum degassing units is operated in response to fluctuations in production volume , Enabling agile response.
[0022]
However, the composition of the molten glass G obtained may be slightly different between the vacuum degassing parts 11 and 12 if the two machines are simply arranged in parallel. For example, it is technically difficult to completely match the degree of vacuum in the vacuum degassing tanks 14 and 15 between the two vacuum degassing parts 11 and 12, so that the molten glass between the vacuum degassing tanks 14 and 15 is molten. The pressure of the gas phase in contact with G differs, so that the concentration (partial pressure) of the gas component of the molten glass that passes therethrough (for example, SO ₂ , CO _2, etc. in soda-lime glass) also varies. Therefore, the composition of the gas phase components that have contacted the molten glass passing through both apparatuses is different, that is, the composition histories are different, so that molten glasses having slightly different contained gas components are obtained. Can cause bubbles. There is also a difference in volatile components such as Na ₂ O in the mother composition. The molten glass obtained by merging molten glasses having different compositions in this way has a problem that the composition is likely to be uneven, sufficient homogeneity cannot be obtained, and the optical properties of the glass product may be deteriorated. is there.
[0023]
Therefore, the present invention provides a pressure equalizing pipe 42 that allows the first vacuum degassing part 11 and the second vacuum degassing part 12 to communicate with each other, thereby enabling the vacuum degassing treatment of a large amount of molten glass G, It is possible to obtain a molten glass G excellent in homogeneity.
[0024]
Specifically, as shown in FIG. 1, a pressure equalizing pipe 42 is provided in communication between the decompression housing 11 a of the first decompression defoaming part 11 and the decompression housing 12 a of the second decompression defoaming part 12. .
The pressure equalizing pipe 42 is a pipe for maintaining the gas phase in both the vacuum degassing tanks 14 and 15 at the same pressure. For example, as shown in FIG. Are communicated and connected to each other so that the vacuum degassing parts 11 and 12 are communicated with each other. The connection location of the pressure equalizing pipe 42 is not particularly limited, and may be configured so that at least both the decompression housings 11a and 12a communicate with each other. The material and shape of the pressure equalizing tube 42 are not particularly limited, but are preferably made of stainless steel.
[0025]
Thus, since it was set as the structure which connected both the vacuum degassing parts 11 and 12, since the gaseous-phase pressure of both the vacuum degassing tanks 14 and 15 becomes equal, the gas component in the glass contained in a gaseous phase, and in glass The partial pressure (concentration) of the volatilization component (for example, in soda lime glass, gas components such as SO ₂ and CO ₂ and volatilization components such as Na ₂ O) can be made equal. Therefore, since the same composition history can be given to the molten glass G passing through both the vacuum degassing portions 11 and 12, the molten glass G obtained by performing the vacuum degassing treatment from both the vacuum degassing portions 11 and 12 is used. It is possible to obtain a molten glass G having the same composition and excellent in homogeneity with very few bubbles and uneven composition after merging.
[0026]
Incidentally, in the middle of the pressure equalizing pipe 42 is preferably cock 44 for blocking communication between both closes the vacuum degassing vessel 14 and 15 equalizing pressure pipe 42 is provided. That is, when one of the vacuum degassing unit 11 or 12 has become unusable due to maintenance, if closed equalizing pressure pipe 42 by cock 44 and the other of the vacuum degassing unit 11 or 12 subsequently used alone It is possible to minimize the hindrance to the production of glass products. In particular, when platinum or a platinum alloy constituting the decompression defoaming tank 14, the rising pipe 16 and the lowering pipe 18 is damaged, it takes several months to repair it, which is effective.
[0027]
The molten glass G that has been subjected to the vacuum degassing process by the vacuum degassing parts 11 and 12 reaches the joining part 50 via the downcomers 18 and 19.
The merging unit 50 is for merging and stirring the molten glass G supplied from the two vacuum degassing units 11 and 12 and then supplying the molten glass G to the inlet of the next step, for example, a spout.
[0028]
FIG. 2 and FIG. 3 show an example of such a merging portion 50.
The merging section 50 shown in the figure has an elliptical or rectangular parallelepiped furnace material partition wall 52, throat furnace materials 54 and 54, and a stirring device 56, and the furnace material partition wall 52 includes a storage tank 64. 64 and the merging tank 66 are formed.
The furnace material partition wall 52 is a casing for joining the molten glass G supplied from the two downcomers 18 and 19 into one flow path, and has two downcomers 18 and 19 on the upper surface. The lower end portions of the molten glass G are inserted at a predetermined distance from each other, and a discharge port 52a for discharging the joined molten glass G to the outside of the furnace material partition wall 52 is formed on the side surface, but the present invention is not limited thereto. There is no particular limitation as long as the two downcomers 18 and 19 and the downstream stirring device 56 are connected.
[0029]
The throat furnace materials 54 and 54 are plates for preventing a vortex generated by a stirring device 56 described later from reaching the lower ends of the downcomers 18 and 19 and preventing erosion of the lower ends of the downcomers 18 and 19. Throats 54 a and 54 a for discharging the molten glass G flowing out from the pipes 18 and 19 only to the downstream side are formed, and two throats 54 a and 54 a are provided in the furnace material partition wall 52 corresponding to the two downcomers 18 and 19. It is done. Therefore, the two throat furnace materials 54 and 54 partition the downstream sides of the two downcomers 18 and 19, respectively, so that the upstream side of the throat furnace materials 54 and 54 is inside the furnace material partition wall 52. The storage tanks 64 and 64 are formed, and the downstream side sandwiched between the two throat furnace materials 54 and 54 in the furnace material partition wall 52 forms the merge tank 66. That is, in the merging unit 50, the molten glass G supplied and stored in the two storage tanks 64 and 64 is merged in the merging tank 66 via the throats 54a and 54a of the throat furnace material. Is supplied to the stirring device 56 from the discharge port 52a.
[0030]
The stirring device 56 is for stirring and homogenizing the molten glass G joined in the joining tank 66 in the furnace material partition wall 52. Various known stirring devices used for stirring the molten glass are used. There is no particular limitation. The illustrated stirring device 56 includes a canal 58, a stirrer 60, and a drive motor 62.
The canal 58 is for securing a space for stirring the molten glass G and is provided so as to communicate with the discharge port 52a of the furnace material partition wall 52 and accommodate the stirrer 60. The stirrer 60 is formed in the axial direction (for example, in the lower direction) at the position of the stirrer 60, and is formed in the horizontal direction on the upstream side and the downstream side thereof, that is, in a rectangular shape so that the stirring by the 60 can be performed efficiently. It is preferable to do this.
[0031]
The stirrer 60 stirs the molten glass G, and includes a rotating shaft 60a whose upper end is rotatably supported by the drive motor 62, and a rotating blade 60b disposed at the lower end of the rotating shaft 60a. Is done. Therefore, by driving the drive motor 62, the rotating blade 60b rotates through the rotating shaft 60a, and the molten glass G introduced into the canal 58 is forcibly stirred and homogenized. The material and structure of the stirrer 60 are not particularly limited. The surface of the stirrer 60 made of platinum or a platinum alloy, or made of a heat-resistant material other than platinum or a refractory material, such as refractory, is made of platinum. In order to prevent erosion by the molten glass G, lining or platinum alloy lining is preferable.
The drive motor 62 is not particularly limited as long as it can stir the molten glass G, and various known drive means can be used.
[0032]
By constructing the merging portion 50 in this manner, the portion to be agitated by the agitator 56 and the lower ends of the downcomers 18 and 19 are sufficiently separated, and the vortex of the molten glass G generated by the agitation is produced by the downcomer 18. 19 can be prevented from reaching the lower end of the downcomers 18 and 19 and eroding the lower ends of the downcomers 18 and 19, thereby improving the durability of this portion. In particular, as described above, since the interface between the molten glass G and the atmosphere is highly reactive, even at the lower end of the downcomer 18 made of platinum or platinum alloy, the prevention of erosion near the interface is enhanced. It is extremely effective in that it can be used.
[0033]
Here, the molten glass G to be processed by the vacuum degassing apparatus 10 of the present invention is not particularly limited, and examples thereof include soda lime glass and borosilicate glass. The apparatus 10 can process a large amount of molten glass. Therefore, it becomes possible to apply to a large plant such as soda-lime glass that requires a large amount of treatment.
[0034]
An example of a process in which the molten glass G is defoamed with the vacuum degassing apparatus 10 of the present invention and continuously supplied to the next processing furnace will be described below. In addition, since the 1st vacuum degassing part 11 and the 2nd vacuum degassing part 12 are comprised similarly, the effect | action about the 1st vacuum degassing part 11 is mainly demonstrated below.
First, in the melting tank 20, the glass is melted to obtain a molten glass G. The temperature at this time is 1250 to 1450 ° C., preferably 1280 to 1320 ° C. in the case of soda-lime glass. Within this range, the viscosity of the molten glass G can be made sufficiently small, an efficient vacuum degassing treatment can be performed, and deterioration of the apparatus (particularly platinum or platinum alloy) can be suppressed. In addition, about glass of other compositions, such as a borosilicate glass, it is preferable to fuse | melt at the temperature which becomes the same viscosity as the said soda-lime glass.
[0035]
And the inside of the pressure reduction housing 11a and the pressure reduction deaeration tank 14 are maintained in a vacuum suction state by a vacuum pump (not shown). In this state, the glass G melted in the melting tank 20 passes through the pit 22 provided at the downstream end of the melting tank and rises through the riser 16 and is guided into the vacuum degassing tank 14. Defoaming treatment is performed in a vacuum degassing tank 14 under reduced pressure conditions. At this time, the pressure equalizing pipe 42 keeps the gas pressure in the vacuum degassing tank 14 at the same pressure as the gas pressure in the vacuum degassing tank 15 of the second vacuum degassing section 11. The same composition history can be imparted to the molten glass G passing through the portions 12 and 14.
[0036]
Next, the defoamed molten glass G is guided to the merging section 50 through the downcomer 18, merged with the molten glass G from the second vacuum degassing section 12, stirred, and then formed into the next molding. Part (not shown).
In addition, since the vacuum degassing apparatus 10 of this invention is the 2 structure of the 1st vacuum degassing part 11 and the 2nd vacuum degassing part 12, the molten glass G is each a vacuum degassing with two riser pipes. It is supplied to the tank, discharged through the two corresponding downcomers, and supplied to the junction 50.
[0037]
By the way, the parallel vacuum degassing apparatus of the present invention is not limited to the siphon type vacuum degassing apparatus shown in FIG. 2, but also the horizontal vacuum degassing apparatus shown in Japanese Patent Laid-Open Nos. 5-262530 and 7-291633. Of course, it may be applied to.
The parallel vacuum degassing apparatus of the present invention has been described in detail above. However, the present invention is not limited to the above-described embodiments, and various improvements and modifications may be made without departing from the scope of the present invention. Of course.
[0038]
【The invention's effect】
As described above in detail, according to the present invention, a large amount of molten glass can be processed and produced in a vacuum degassing apparatus for molten glass that removes bubbles from continuously supplied molten glass. A molten glass having excellent homogeneity can be obtained while being able to flexibly cope with fluctuations in quantity. Further, it can be used continuously even during maintenance.
[Brief description of the drawings]
FIG. 1 is a schematic sectional view showing an example of a parallel-type vacuum degassing apparatus of the present invention.
FIG. 2 is a schematic cross-sectional view of a first vacuum degassing part and a merging part of the parallel-type vacuum degassing apparatus shown in FIG.
FIG. 3 is a schematic cross-sectional view showing an example of a merging section in the parallel-type vacuum degassing apparatus shown in FIG.
FIG. 4 is a schematic sectional view showing an example of a conventional vacuum degassing apparatus.
[Explanation of symbols]
10 (Parallel type) vacuum degassing device 11 first vacuum degassing part 11a vacuum housing 12 second vacuum degassing part 12a vacuum housing 14, 15 vacuum degassing tank 16 ascending pipe 18, 19 descending pipe 20 dissolution tank 22 upstream pit 30 Electroformed refractory 32 Heat insulation brick 42 Pressure equalizing pipe 44 Cock 50 Junction section 52 Furnace material partition wall
52a Discharge port 54 Throat furnace material
54a Throat 56 Stirrer 58 Canal 60 Stirrer
60a Rotating shaft
60b Rotary blade 62 Drive motor 64 Storage tank 66 Merge tank
100 Vacuum degassing equipment
102 Dissolution tank
104 decompression housing
106 Defoaming tank
108 riser
110 Downcomer
112 Thermal insulation

Claims (6)

Two vacuum degassing parts for performing vacuum degassing of the molten glass supplied from the melting tank, and a merging part for joining the molten glass supplied from the two vacuum degassing parts, stirring them, and supplying them to the downstream side And
The two vacuum degassing sections are respectively connected to the vacuum housing that is vacuum-sucked, a vacuum degassing tank that is provided in the vacuum housing and degassed the molten glass, and communicates with the vacuum degassing tank. Introducing means for introducing molten glass before depressurized defoaming supplied from the melting tank into the depressurized defoaming tank, and communicating with the depressurized defoaming tank, and molten glass after depressurized defoaming And deriving means for deriving from the vacuum degassing tank to the merging section,
Furthermore, it has a pressure equalization pipe | tube which mutually connects the said two vacuum degassing parts, The parallel type vacuum degassing apparatus characterized by the above-mentioned. The introducing means is a riser pipe that raises the molten glass before the vacuum degassing and introduces it into the vacuum degassing tank, and the derivation means lowers the molten glass after the vacuum degassing from the vacuum degassing tank. The parallel-type vacuum degassing apparatus according to claim 1, which is a downcomer pipe led out to the junction. The merging section includes two storage tanks through which the two derivation means communicate with each other, a merging tank provided so as to communicate with both of the two storage tanks via a throat, and a downstream side of the merging tank. The parallel-type vacuum degassing apparatus according to claim 1, further comprising a stirrer provided in communication. 4. The parallel-type vacuum degassing apparatus according to claim 1, wherein the pressure equalizing pipe is provided with a cock for blocking communication between the vacuum degassing tanks of the two vacuum degassing sections. The parallel-type vacuum degassing apparatus according to any one of claims 1 to 4, wherein the molten glass is soda-lime glass. The parallel decompression according to any one of claims 1 to 5, wherein at least a main portion that directly contacts the molten glass is formed of an electroformed refractory in the introduction unit, the vacuum degassing tank, and the lead-out unit. Defoaming device.

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