Method for producing glass article

Abstract

Provided is a method for producing a glass article, the method comprising: a connection step P1 for connecting a batch bin 2 from above to an inlet part 18 of a silo 3; a supply step P2 for transferring and supplying a glass raw material 5 in the batch bin 2 into the silo 3; a storing step P3 for storing the supplied glass raw material 5 in the silo 3; an input step P4 for introducing the glass raw material 5 in the silo 3 into a melting furnace 4; and a melting step P5 for heating and melting the glass raw material 5 introduced into the melting furnace 4 to produce a molten glass 6, wherein the period from the start to the completion of the supply step P2 includes a period in which the glass raw material 5 is supplied while maintaining the state of the glass raw material 5 deposited up to the inlet part 18 in the silo 3.

Description

Method for manufacturing glass articles

[0001] The present disclosure relates to a method for manufacturing a glass article.

[0002] Glass articles, such as glass plates, glass tubes, and glass fibers, are manufactured by heating and melting glass raw materials introduced into a melting furnace to produce molten glass, and then molding the molten glass into a predetermined shape.

[0003] The glass raw material is prepared by blending and mixing a plurality of inorganic raw materials such as silica, aluminum oxide, cullet, etc. in a predetermined ratio. Patent Document 1 discloses an example of a procedure from blending and mixing a plurality of inorganic raw materials to obtain a glass raw material, to charging the glass raw material into a melting furnace.

[0004] In this procedure, the same container is used for the above-mentioned blending and charging. Specifically, first, each of the multiple inorganic raw materials is weighed and then collected in a container to be blended. Next, the container is transported to a mixer, and the inorganic raw materials are mixed by rotating and shaking to obtain glass raw materials. After that, the container is placed in a hopper, and the glass raw materials in the container are charged into a melting furnace.

[0005] JP 2010-105872 A

[0006] In addition to the procedure disclosed in Patent Document 1, the following procedure is one example of the procedure for charging the obtained glass raw material into a melting furnace.

[0007] First, in a blending facility, glass raw materials obtained by blending and mixing multiple inorganic raw materials are placed in a batch bin, which is a container for transport. Next, the glass raw materials in the batch bin are transferred to a silo, which is a facility for storing the glass raw materials, and supplied. Specifically, the batch bin transported from the blending facility to the silo is connected to the silo's intake from above, and the glass raw materials in the batch bin are allowed to fall by gravity and supplied into the silo. Thereafter, the glass raw materials stored in the silo are sequentially charged into a melting furnace.

[0008] In the above-mentioned embodiment using a batch bin and a silo, when the glass raw material in the batch bin is transferred and supplied into the silo, the following problems arise due to the impact of the glass raw material falling.

[0009] As shown in Fig. 6, when the frit 100 falls from the intake section 200a into the silo 200 due to gravity, the frit 100 around the falling point 300 is blown up by the impact. This causes a problem of separation (segregation) of the frit 100. The "segregation" here means that the frit 100 is blown up, causing particle size differences in the frit 100 depending on the distance from the falling point 300 (large particle size near the falling point 300, small particle size far from the falling point 300), resulting in heterogeneity of the frit 100 in the silo 200. Since producing a glass article from heterogeneous frit 100 leads to deterioration in quality, the establishment of a technology that can avoid the separation of the frit 100 has been anticipated.

[0010] In view of the above circumstances, a technical problem to be solved is to avoid, as much as possible, separation of glass raw materials accompanying the execution of a step of transferring glass raw materials in a batch bin into a silo and supplying the glass raw materials in the step when producing a glass article.

[0011] A first method for manufacturing a glass article for solving the above problem is a method for manufacturing a glass article, comprising: a connecting step of connecting a batch bin to an intake section of a silo from above; a supply step of transferring and supplying the glass raw material in the batch bin into the silo; a storing step of storing the supplied glass raw material in the silo; a feeding step of feeding the glass raw material in the silo into a melting furnace; and a melting step of heating and melting the glass raw material fed into the melting furnace to produce molten glass, and is characterized in that the method includes a period from the start to the completion of the feeding step in which the glass raw material is supplied while maintaining a state in which the glass raw material is piled up in the silo up to the intake section.

[0012] In the first method for producing a glass article, during the above period, the glass frit is maintained in a state in which it is piled up to the intake section in the silo, and the glass frit is supplied into the silo under the same state. By accumulating the glass frit up to the intake section in this manner, it is possible to inevitably prevent the glass frit supplied into the silo from falling by gravity. Therefore, it is also possible to prevent the glass frit from flying up in the silo due to the impact of the fall. As a result, separation of the glass frit can be reliably avoided during the above period. From the above, according to this production method, when a step of transferring glass frit from a batch bin into a silo and supplying the same is performed in producing a glass article, separation of the glass frit accompanying the execution of the step can be avoided as much as possible.

[0013] The second method for producing a glass article is the same as the first method described above, except that the supplying step is started in a state in which a space not filled with glass raw material is formed in the upper part of the silo.

[0014] When the empty batch bin has finished supplying the glass frit into the silo, it is disconnected from the intake of the silo, and a new batch bin (containing glass frit) is connected to the intake instead. It may be difficult to always maintain a state in which glass frit is piled up to the intake of the silo, including when replacing the batch bin. Therefore, as in the second method for producing a glass article, if the supply step is allowed to start in a state in which a space not filled with glass frit is formed in the upper part of the silo (a state in which glass frit is not piled up to the intake), the difficulty of operation can be reduced.

[0015] The third method for producing a glass article is the same as the first or second method, except that, at the start of the supply step, the difference in height between the supply port of the batch bin and the upper surface of the glass raw material stored in the silo is 1.5 m or less.

[0016] In the third method for producing a glass article, even if the glass frits supplied into the silo are supplied while falling due to gravity, by making the height difference 1.5 m or less, it is possible to minimize the flying up of the glass frits in the silo due to the impact of the fall, which is further advantageous in avoiding separation of the glass frits.

[0017] A fourth method for producing a glass article is any one of the first to third methods, wherein in the supplying step, the proportion of the glass raw materials supplied into the silo during the period relative to the total amount of the glass raw materials supplied into the silo is 70% by mass or more.

[0018] In the fourth method for producing a glass article, the proportion of glass frits supplied during the period in which separation can be reliably avoided is as high as 70% or more, which is more advantageous in avoiding separation of the glass frits.

[0019] A fifth method for producing a glass article is any one of the first to fourth methods described above, wherein when the flow rate of molten glass discharged from the melting furnace is A [ton / day] and the mass of molten glass contained in the melting furnace is B [ton], the relationship (B / A) > 2 is satisfied.

[0020] In the fifth method for producing a glass article, because of the above-mentioned relationship (B / A) > 2, the glass raw material charged into the melting furnace is allowed to remain in the melting furnace in the form of molten glass for a sufficiently long time after being melted. This sufficiently long residence time allows the effects of separation to be evened out in the melting furnace, making it possible to improve the quality of the produced glass article.

[0021] According to the method for manufacturing a glass article according to the present disclosure, when a step of transferring glass raw materials in a batch bin into a silo and supplying the glass raw materials is carried out in manufacturing a glass article, separation of the glass raw materials that accompanies the step can be avoided as much as possible.

[0022] Fig. 1 is a partial cross-sectional view schematically showing a method for manufacturing a glass article; Fig. 2 is a cross-sectional view showing a connecting step in the method for manufacturing a glass article; Fig. 3 is a cross-sectional view showing a supplying step in the method for manufacturing a glass article; Fig. 4 is a cross-sectional view showing a supplying step in the method for manufacturing a glass article; Fig. 5 is a cross-sectional view for explaining a problem in the prior art.

[0023] Hereinafter, a method for manufacturing a glass article according to an embodiment will be described with reference to the drawings.

[0024] A manufacturing apparatus 1 used to carry out a glass article manufacturing method (hereinafter referred to as the present manufacturing method) is shown schematically in Figure 1. As shown in the figure, the present manufacturing apparatus 1 includes a batch bin 2, a silo 3, and a melting furnace 4.

[0025] The batch bin 2 is a container for transporting the glass raw material 5 stored therein from the blending facility to the silo 3. The silo 3 is provided next to the melting furnace 4 and is a facility for storing the glass raw material 5 supplied from the batch bin 2. The melting furnace 4 is a facility for producing molten glass 6 from the glass raw material 5 charged into the furnace.

[0026] 2 to 5, the batch bin 2 includes a receiving section 7 for receiving the glass raw material 5, a bin body 9 having a space 8 for accommodating the glass raw material 5, and a supply section 10 for supplying the glass raw material 5 to the silo 3. The receiving section 7 and the supply section 10 are both formed in a tubular shape (for example, a cylindrical or rectangular tubular shape) with an axis extending in the vertical direction.

[0027] The receiving part 7 has an inlet 11 for receiving the glass raw material 5. The upper end of the receiving part 7 where the inlet 11 is located is formed in a flange shape. The inlet 11 can be closed with a closing member 12 (for example, a lid).

[0028] The bottle body 9 has an upper tubular portion 13 and a lower tubular portion 14. The inner peripheral surfaces of both tubular portions 13, 14 are continuous, and the above-mentioned space 8 is formed on the inner peripheral side of both tubular portions 13, 14. Both tubular portions 13, 14 have larger opening areas in cross sections perpendicular to the vertical direction compared to the receiving portion 7 and the supplying portion 10. The upper tubular portion 13 is connected to the lower end of the receiving portion 7. Meanwhile, the lower tubular portion 14 is connected to the upper end of the supplying portion 10. The upper tubular portion 13 is formed in a cylindrical or rectangular tubular shape. The lower tubular portion 14 is formed in a conical or pyramidal shape, and the opening area in a cross section perpendicular to the vertical direction decreases as it moves downward.

[0029] The supply unit 10 has a supply port 15 for the frit 5. The lower end of the supply unit 10 where the supply port 15 is located is formed in a flange shape. Of the lower end of the supply unit 10, a portion that comes into contact with a chute 16 of the silo 3, which will be described later, is made of an elastic body (rubber, for example). The supply unit 10 is provided with a valve 17 (a butterfly valve, for example). When the valve 17 is in a closed state (the state shown in FIG. 2), the frit 5 cannot pass through the supply unit 10. On the other hand, when the valve 17 is in an open state (the states shown in FIGS. 3 to 5), the frit 5 can pass through the supply unit 10.

[0030] Here, the size of the batch bin 2 will be exemplified. The height dimension H1 (see FIG. 2) of the batch bin 2 is, for example, 1.5 to 2.5 m, preferably 1.8 to 2.0 m. The width dimension W1 (see FIG. 2) of the batch bin 2 is, for example, 1.0 to 1.5 m, preferably 1.0 to 1.3 m. The mass of the glass raw material 5 that can be accommodated in the batch bin 2 is, for example, 0.5 to 2.0 ton, preferably 1.0 to 1.2 ton.

[0031] 2 to 5, the silo 3 includes an intake section 18 for taking in the glass raw material 5, a chute 16 combined with the intake section 18, and a silo main body section 20 in which a space 19 for storing (accommodating) the glass raw material 5 is formed. The intake section 18, the chute 16, and the silo main body section 20 are all formed in a tubular shape (for example, a cylindrical shape or a rectangular tubular shape) with an axis extending in the vertical direction.

[0032] The intake section 18 is connected to the upper end (ceiling) of the silo main body section 20 .

[0033] The chute 16 is disposed on the inner periphery of the intake section 18. The chute 16 is movable relative to the intake section 18. Specifically, the chute 16 can be raised and lowered while remaining combined with the intake section 18. When the chute 16 is raised, the lower end of the supply section 10 of the batch bin 2 and the upper end of the chute 16 are butted against each other. In this state, the supply section 10 of the batch bin 2 and the chute 16 form a continuous passage for the glass raw material 5. The chute 16 is held in the intake section 18 in a manner that allows it to be raised and lowered. The upper end of the chute 16 is formed in a flange shape. A portion of the upper end of the chute 16 that comes into contact with the supply section 10 of the batch bin 2 is made of an elastic material (e.g., rubber). Note that instead of being held in the intake section 18 in a manner that allows it to be raised and lowered, the chute 16 may be configured to be extendable and retractable. In this case, the chute 16 may be formed of a bellows hose or the like.

[0034] The silo main body 20 has a larger opening area in a cross section perpendicular to the vertical direction than the inlet 18. The silo main body 20 has a conical or pyramidal shape near its lower end, and the opening area in a cross section perpendicular to the vertical direction decreases downward (see FIG. 1 ). An outlet 21 (see FIG. 1 ) for discharging the glass raw material 5 out of the silo 3 is formed at the lower end of the silo main body 20.

[0035] Although not shown in the figure, a leveler for detecting a decrease in the amount of glass frit 5 in the silo 3 is disposed at the upper part of the silo main body 20 (near the ceiling of the silo main body 20 in the space 19). The leveler detects a decrease in the height position of the upper surface 5a of the glass frit 5 to detect a decrease in the amount of glass frit 5. A rotary leveler or a laser leveler can be used as the leveler. For example, the rotary leveler has a propeller-shaped or rod-shaped rotor that rotates around an axis extending in the vertical direction. A torque for rotation is always applied to the rotor. When the rotor becomes buried in the glass frit 5, the raw materials act as resistance and the rotor stops rotating. On the other hand, when the rotor becomes exposed from the raw materials as the glass frit 5 decreases, the rotor resumes rotation.

[0036] Here, the size of the silo 3 will be exemplified. The height H2 of the silo 3 (the dimension from the lower end of the silo 3 to the upper end of the intake part 18, see FIG. 2) is, for example, 2.0 to 3.0 m. The width W2 of the silo 3 (see FIG. 2) is, for example, 0.7 to 1.0 m. The mass of the glass frit 5 that can be stored in the silo 3 is, for example, 1.0 to 2.0 ton. The ratio of the mass of the glass frit 5 that can be stored in the silo 3 to the mass of the glass frit 5 that can be accommodated in the above-mentioned batch bin 2 is, for example, 50 to 200%.

[0037] 1 has a rectangular outer shape in plan view, for example, and includes a bottom wall 22, a ceiling wall 23, a front wall 24, a rear wall 25, and a pair of side walls 26.

[0038] Electrodes 27, 28 for electrically heating the molten glass 6 in the melting furnace 4 are arranged on the bottom wall 22 and the side wall 26, respectively. A combustion burner (not shown) capable of spraying flames is also arranged on the side wall 26. A charger 29 (a screw feeder in the illustrated example) for charging glass raw materials 5 into the melting furnace 4 is arranged on the front wall 24. An outlet 30 for allowing the molten glass 6 produced in the melting furnace 4 to flow out of the furnace is arranged on the rear wall 25 opposite the front wall 24.

[0039] The present manufacturing method, which is carried out using the above-described manufacturing apparatus 1, includes, in order from the upstream process, a connecting process P1 (FIG. 2), a supplying process P2 (FIGS. 3 and 4), a storage process P3 (FIG. 5), a throwing process P4 (FIG. 1), and a melting process P5 (FIG. 1).

[0040] The connecting step P1 shown in Fig. 2 is a step of connecting the batch bin 2 from above to the intake 18 of the silo 3. The space 8 of the batch bin 2 contains glass raw material 5 obtained by compounding and mixing a plurality of inorganic raw materials, such as silica, aluminum oxide, and cullet. In this embodiment, the intake 18 and the batch bin 2 are indirectly connected via the chute 16. Of course, this is not limited to this, and as a modification of this embodiment, the chute 16 may be removed and the intake 18 and the batch bin 2 may be directly connected. Furthermore, in this embodiment, the chute 16 is attached inside the intake 18 of the silo 3, but it does not necessarily have to be on the inside. For example, the chute 16 may be attached so as to extend upward (toward the batch bin) from the upper end of the intake 18.

[0041] When connecting the intake section 18 of the silo 3 and the batch bin 2, the batch bin 2 is fixed and installed above the silo 3, and then the chute 16 is raised. Specifically, the chute 16 is raised from the position shown by the solid line in Figure 2 to the position shown by the two-dot chain line. As the chute 16 rises, the lower end of the supply section 10 of the batch bin 2 and the upper end of the chute 16 are butted together. This connects the intake section 18 and the batch bin 2 via the chute 16, completing the connecting step P1. Note that during the connecting step P1, the valve 17 provided in the supply section 10 of the batch bin 2 is in a closed state.

[0042] The supply step P2 shown in Figures 3 and 4 is a step of transferring and supplying the glass frit 5 in the batch bin 2 into the silo 3. At the start of the supply step P2, as shown in Figure 3, the valve 17 provided in the supply part 10 of the batch bin 2 is switched from a closed state to an open state. This allows the glass frit 5 to pass through the supply part 10, and the glass frit 5 falls by gravity.

[0043] At the start of the supplying step P2, a space 31 in which the glass frit 5 is not filled is formed in the upper part of the silo 3 (in the silo main body 20). The volume of the space 31 is sufficiently smaller than the volume of the glass frit 5 contained in the batch bin 2.

[0044] At the start of the supply step P2, in order to avoid segregation caused by the falling of the glass frit 5 as much as possible, the height difference D between the supply port 15 of the batch bin 2 and the upper surface 5a of the glass frit 5 stored in the silo 3 is preferably 1.5 m or less, more preferably 1.0 m or less. In the illustrated example, the upper surface 5a of the glass frit 5 is flat, but this is not limited thereto. For example, the upper surface 5a may have a mountain-like shape that rises toward the center (near the axis of the silo main body 20), or may have a valley-like shape that is recessed toward the center. Therefore, the "height difference D" referred to here means the height difference between the supply port 15 of the batch bin 2 and the center of the upper surface 5a of the glass frit 5.

[0045] At the start of the supply step P2, it is preferable to satisfy the following condition from the viewpoint of (1) easily realizing the above-mentioned relationship (volume<volume) between the volume of the space 31 and the volume of the frit material 5 in the batch bin 2, and (2) making the height difference D as small as possible. That is, at the start of the supply step P2, it is preferable to satisfy the condition that the ratio of the height dimension L2 (the dimension from the bottom of the silo main body 20 to the upper surface 5a of the frit material 5) in the silo 3 to the height dimension L1 (the dimension from the bottom to the ceiling of the silo main body 20) of the space 19 in the silo 3 is 70% or more. It is more preferable that the ratio is 80% or more, and even more preferable that it is 90% or more.

[0046] As described above, at the start of the supplying step P2, the volume of the space 31 is smaller than the volume of the frit 5 in the batch bin 2. Therefore, immediately after the start of the supplying step P2, only a part of the frit 5 in the batch bin 2 is accommodated in the space 31. The frit 5 that does not fit in the space 31 is accumulated in the intake part 18 located above the space 31. Furthermore, depending on the volume of the frit 5 accommodated in the batch bin 2, the frit 5 may be accumulated further above the intake part 18, resulting in a state as shown in FIG. 4 as an example. In the illustrated example, the frit 5 is accumulated up to the bottom cylinder part 14 of the batch bin 2.

[0047] 4, as the frit 5 is successively discharged from the outlet 21 of the silo 3, the frit 5 in the same amount as the discharged amount flows downward and is newly transferred into the silo 3. When all the frit 5 are transferred into the silo 3, the supply step P2 is completed.

[0048] During the period from the start to the completion of the supply step P2 after the transition to the state shown in Fig. 4, the state in which the frit 5 is piled up to the intake part 18 in the silo 3 is maintained, and the frit 5 is supplied into the silo 3 under the same state. Therefore, the frit 5 supplied into the silo 3 can be prevented from being supplied while falling by gravity. Therefore, it can also be prevented that the frit 5 is blown up in the silo 3 due to the impact of falling. As a result, during the above period, separation (segregation) of the frit 5 can be reliably avoided.

[0049] Here, the ratio of the frit 5 to be supplied into the silo 3 during the above-mentioned period to the total amount of frit 5 to be supplied into the silo 3 (the total amount of frit 5 contained in the batch bin 2 before the start of the supplying step P2) is preferably 70% or more, more preferably 80% or more, and further more preferably 90% or more, by mass%.

[0050] The storing step P3 shown in Fig. 5 is a step of storing the glass frit 5 supplied from the batch bin 2 in the silo 3. Specifically, the glass frit 5 supplied from the batch bin 2 and before being discharged from the outlet 21 is stored in the silo 3.

[0051] 5, there is no glass raw material 5 in the batch bin 2, and the batch bin 2 is empty. In preparation for the next supply step P2, the empty batch bin 2 is disconnected from the intake part 18 of the silo 3 and then replaced with a new batch bin 2 (a batch bin 2 containing glass raw material 5). The procedure for replacing the empty batch bin 2 with a new batch bin 2 and the timing of replacement will be described below.

[0052] First, by lowering the chute 16 from the state shown in Figure 5, the lower end of the supply section 10 of the batch bin 2 and the upper end of the chute 16 are separated. This releases the connection between the intake section 18 of the silo 3 and the empty batch bin 2. Next, the empty batch bin 2 is carried out from above the silo 3. Thereafter, the intake section 18 of the silo 3 is connected to a new batch bin 2 in the same manner as in the connection step P1 described above. The empty batch bin 2 is replaced with a new batch bin 2 through the above procedure.

[0053] The timing of replacing the empty batch bin 2 with a new batch bin 2 is preferably before the ratio of the height dimension L2 to the height dimension L1 reaches 70% as the amount of glass frit 5 in the silo 3 decreases. The reason why this timing is preferable is that, from the viewpoints of (1) and (2) described above, the ratio should be 70% or more at the start of the supply process P2 using the new batch bin 2. To perform the replacement at this timing, the rotary leveler is used. For example, the ratio is set to 80%, which is greater than 70%, as a reference, and the vertical position of the rotor of the rotary leveler is adjusted so that the rotor rotates when the ratio falls below 80%. After making this adjustment, the replacement can be performed when the rotor starts to rotate. In this way, even if the amount of glass frit 5 in the silo 3 decreases during replacement, the ratio can be easily made 70% or more at the start of the supply process P2 using the new batch bin 2 after replacement.

[0054] 1 is a step of charging the glass frit 5 in the silo 3 into the melting furnace 4. Specifically, the glass frit 5 discharged from the outlet 21 of the silo 3 to the outside of the silo 3 is charged into the melting furnace 4 via a hopper, a charger 29, or the like (not shown). The glass frit 5 charged into the melting furnace 4 is supplied above the liquid surface 6a of the molten glass 6 contained in the furnace.

[0055] The melting step P5 shown in Fig. 1 is a step of generating molten glass 6 by heating and melting glass frit 5 charged into melting furnace 4. Specifically, glass frit 5 is heated and melted by electrically heating molten glass 6 using electrodes 27, 28 and / or by heating using a combustion burner (not shown). The molten glass 6 generated in melting furnace 4 is discharged from outlet 30 to the outside of the furnace and sent to a downstream step. In the downstream step, for example, fining, homogenization, etc. of molten glass 6 are performed, and then the molten glass 6 is formed into a predetermined shape to produce a glass article (glass plate, glass tube, glass fiber, etc.).

[0056] In this production method, when the flow rate of molten glass 6 discharged from melting furnace 4 (outlet 30) to the outside of the furnace is A [ton / day] and the mass of molten glass 6 contained in melting furnace 4 is B [ton], it is preferable to satisfy the relationship (B / A) > 2. For example, the flow rate A is 20 to 40 ton / day. For example, the mass B is 50 to 150 ton.

[0057] The value of (B / A) is more preferably (B / A)>2.5. The larger the value of (B / A), the longer the time that the molten glass 6 produced in the melting furnace 4 stays in the furnace. As a result, even if separation of the glass raw material 5 occurs in the supply step P2, the effect of the separation is leveled in the melting furnace 4, and deterioration in the quality of the glass article can be prevented.

[0058] Here, the following modified examples can also be applied to the above embodiment. In the above embodiment, the supplying step P2 is started in a state where a space 31 not filled with the glass frit 5 is formed in the upper part of the silo 3 (in the silo main body 20). However, this is not limited thereto, and the supplying step P2 may be started in a state where the glass frit 5 is filled entirely in the silo 3 (in the silo main body 20).

[0059] 2 Batch bin 3 Silo 4 Melting furnace 5 Glass raw material 5a Upper surface of glass raw material 6 Molten glass 15 Supply port 18 Intake section 31 Space D Height difference P1 Connecting process P2 Supply process P3 Storing process P4 Charging process P5 Melting process

Claims

1. A method for manufacturing a glass article, comprising: a connecting step of connecting a batch bin to an intake part of a silo from above; a supplying step of transferring and supplying the glass frit in the batch bin into the silo; a storing step of storing the supplied glass frit in the silo; a feeding step of feeding the glass frit in the silo into a melting furnace; and a melting step of heating and melting the glass frit fed into the melting furnace to produce molten glass, the method comprising the steps of: (1) supplying the glass frit while maintaining the glass frit piled up in the silo up to the intake part; 2. The method for manufacturing a glass article according to claim 1, characterized in that the supplying step is started in a state in which a space not filled with the glass raw material is formed in the upper part of the silo.

3. A method for manufacturing a glass article as described in claim 1 or 2, characterized in that at the start of the supply process, the difference in height between the supply port of the batch bin and the upper surface of the glass raw material stored in the silo is 1.5 m or less.

4. A method for manufacturing a glass article as described in claim 1 or 2, characterized in that in the supplying process, the proportion of the glass raw material supplied to the silo during the period relative to the total amount of the glass raw material supplied to the silo is 70% or more by mass.

5. The method for manufacturing a glass article according to claim 1 or 2, characterized in that, when the flow rate of the molten glass discharged from the melting furnace is A [ton / day] and the mass of the molten glass contained in the melting furnace is B [ton], the relationship (B / A)>2 is satisfied.

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