Ultra-thin glass bubble defect control method

Abstract

The invention discloses a method for controlling bubble defects in ultra-thin glass, and belongs to the technical field of glass production. The invention achieves the purpose of controlling bubble defects in glass plates from aspects such as kiln temperature change control and bubbler bubbling frequency adjustment. Compared with the traditional adjustment method, the control method of the invention improves the degree of automatic control of the kiln, reduces glass quality problems caused by emergencies and manual errors, and improves the yield rate of glass products.

Description

Technical Field

[0001] The invention relates to the technical field of glass production, and in particular to a method for controlling bubble defects in ultra-thin glass. Background Art

[0002] In the production process of float ultra-thin electronic glass, there are often bubble defects in the glass plate and it is difficult to control. At present, the adjustment method for bubble defects on the glass surface is generally through manual judgment by experienced engineers, and feedback to the melting control room for manual debugging. This method requires very high experience of personnel and is prone to misjudgment, which seriously affects the glass yield. Therefore, in order to solve this problem, it is urgent to develop a method that can accurately control the bubble defects of ultra-thin glass to improve the yield of glass products. Summary of the invention

[0003] The technical problem to be solved by the present invention is: to overcome the shortcomings of the prior art, to provide a method for controlling bubble defects in ultra-thin glass, to improve the degree of automatic control of the kiln, to reduce glass quality problems caused by emergencies and manual errors, and to improve the yield rate of glass products.

[0004] The technical solution of the present invention is:

[0005] The method for controlling bubble defects in ultra-thin glass comprises the following steps:

[0006] S1 Control of open bubbles on the plate: When the diameter of the open bubbles on the plate is ≤2.5μm, increase the natural gas release of the spray gun in the melting part of the furnace and the combustion-supporting air volume of the small furnace to raise the temperature at the bubbler to the standard temperature, which can improve this type of bubble defect;

[0007] S2 controls bubbles on the board, bubbles in the board, and bubbles under the board:

[0008] Generally, the defects of bubbles on the plate, bubbles in the plate and bubbles under the plate are caused by temperature changes in the kiln or too low bubbling frequency of the bubbler, and the smaller the diameter of the bubble, the farther it comes from the upstream of the kiln. Therefore, for bubbles of different diameters, the measures to eliminate bubble defects are different:

[0009] S21 When the bubble diameter is greater than 2.5 μm, increasing the bubble frequency of the bubbler can improve this type of bubble defect;

[0010] S22 When 1.5μm<bubble diameter≤2.5μm, increase the natural gas release of the spray gun in the melting part of the kiln and the combustion-supporting air volume of the small furnace to raise the temperature at the bubbler to the standard temperature; at the same time, increase the bubbling frequency of the bubbler to improve this type of bubble defect;

[0011] S23 When the bubble diameter is ≤1.5μm, increase the natural gas release of the spray gun in the melting part of the kiln and the combustion-supporting air volume of the small furnace to raise the temperature at the bubbler to the standard temperature; at the same time, increase the bubbling frequency of the bubbler; and turn on the LPG combustion system in the cooling part of the kiln to increase the temperature of the cooling part to ensure that the temperature of the clarification part of the kiln does not lose, which can improve this type of bubble defect;

[0012] S2 Control of open bubbles under the board: If the open bubbles under the board appear only once or disappear after several times, no treatment is required; if such bubbles are continuously generated, find the leak point of the tin bath, drill a hole at the bottom of the tin bath to the leak point, and add filler into the leak point to improve such bubble defects.

[0013] The aforementioned open bubbles on the plate, bubbles on the plate, bubbles in the plate, bubbles under the plate and open bubbles under the plate all refer to the positions of the bubble defects on the glass plate. Figure 2 As shown in the figure, open bubbles on the plate refer to bubbles located on the upper surface of the glass plate, and open bubbles under the plate refer to bubbles located on the lower surface of the glass plate. Bubbles on the plate, bubbles in the plate, and bubbles under the plate are based on the horizontal center line of the glass plate. Bubbles that are completely inside the glass plate and above the center line are bubbles on the plate, bubbles that are completely inside the glass plate and intersect the center line are bubbles in the plate, and bubbles that are completely inside the glass plate and below the center line are bubbles under the plate.

[0014] The bubble sizes are classified into grades: grade one when the bubble diameter is greater than 2.5 μm; grade two when the bubble diameter is 1.5 μm and less than or equal to 2.5 μm; grade three when the bubble diameter is less than or equal to 1.5 μm.

[0015] In addition, in the aforementioned control method for eliminating bubble defects, the standard temperature refers to the standard production temperature that the melting part of the kiln needs to reach during glass production. The standard temperatures of different types of glass are different and are known to those skilled in the art, so they will not be repeated here.

[0016] In addition, if two or more levels of bubbles appear on the glass plate at the same time, for example, level 3 and level 1 bubbles appear at the same time, then based on the principle that the smaller the bubble diameter, the more difficult it is to control, it should be handled according to the standards for level 3 bubbles.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] Compared with the traditional adjustment method, the control method of the present invention improves the degree of automatic control of the kiln, reduces the glass quality problems caused by emergencies and manual errors; at the same time, it also shortens the time for problem investigation and avoids the problem of untimely treatment. The treatment measures formulated according to the present invention solve the bubble defects of the glass plate, make the produced glass have good properties, and improve the yield rate of glass products. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 It is a schematic diagram of the structure of the kiln.

[0021] Figure 2 This is a schematic diagram of the positions of five types of bubbles on the glass plate.

[0022] In the figure, 1, melting section; 2, clarification section; 3, cooling section; 4, small furnace; 5, temperature measuring thermocouple; 6, bubbler; 7, LPG combustion system. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0024] like Figure 1 As shown, the kiln in the following embodiment includes a melting part 1, a clarification part 2 and a cooling part 3, wherein a small furnace 4 and a temperature measuring thermocouple 5 are provided in the melting part 1, and a spray gun is provided in the small furnace 4; and a bubbler 6 is provided in the glass liquid of the melting part 1. The cooling part 3 is provided with an LPG combustion system 7 and a temperature measuring thermocouple 5. The structure of the kiln is a conventional kiln structure in the art, and its specific detailed structure is not repeated here.

[0025] Example 1

[0026] The automatic inspection machine (Isra Visual Equipment Manufacturing (Shanghai) Co., Ltd., G5-10) on the production line detected the presence of open bubbles on the second and third level plates of the glass plate. Generally, open bubbles on the plate are caused by changes in the furnace temperature, and the smaller the diameter of the bubble, the farther it comes from the upstream of the furnace. Therefore, after detecting the open bubbles on the second and third level plates, it is necessary to consider the problems upstream of the furnace.

[0027] As the glass liquid flows in the furnace bubbler 6, the gas in the glass liquid floats upward under the influence of buoyancy, and during the floating period, it merges or drives the small bubbles existing in the glass liquid to float upward, and finally explodes on the surface of the glass liquid, achieving the purpose of removing bubbles in the glass liquid. Therefore, when the second and third level open bubbles are detected on the board, it can be determined that when the bubbles are driven to float and explode, the surface of the glass liquid cannot be actively flattened due to insufficient temperature, thus forming open bubbles on the board.

[0028] At this time, the temperature change curve in the kiln temperature control system is observed. The standard temperature of the melting part 1 of the kiln is 1530°C, while the temperature detected by the temperature measuring thermocouple 5 is 1490°C, which is lower than 1530°C. The temperature of the melting part 1 of the kiln needs to be raised to the standard temperature of 1530°C. The natural gas release of the spray gun in the melting part 1 of the kiln and the combustion-supporting air volume of the small furnace 4 are increased to raise the temperature at the bubbler 6 to the standard temperature of 1530°C. After adjusting the temperature, the production line runs for a period of time and then the bubble defects of the glass are detected by the automatic detection and inspection machine. It is found that the open bubbles on the second and third level boards are eliminated, which proves that the measures of this embodiment can indeed control the open bubble defects on the second and third level boards.

[0029] Example 2

[0030] If the automatic detection and inspection machine of the production line detects the existence of primary bubbles on the plate, bubbles in the plate, and bubbles under the plate on the glass plate at the same time, it is necessary to consider the problems occurring upstream of the kiln. Such bubbles are generally caused by the frequency of the bubbler 6 being too low. During the bubbling process, the gas is introduced to fuse or drive the tiny bubbles in the glass liquid to float and eliminate. Due to the low frequency, the tiny bubbles are leaked or melted, thus generating such tiny bubbles. At this time, it is only necessary to increase the bubbling frequency appropriately to improve such bubble defects. The original bubbling frequency was 7s / time, which was adjusted to 6s / time. After the production line ran for a period of time, the bubble defects of the glass were detected by the automatic detection and inspection machine. It was found that the primary bubbles on the plate, bubbles in the plate, and bubbles under the plate were all eliminated, proving that the measures of this embodiment can indeed control the primary bubbles on the plate, bubbles in the plate, and bubbles under the plate defects.

[0031] Example 3

[0032] The automatic detection and inspection machine of the production line detected the existence of secondary bubbles on the plate, bubbles in the plate and bubbles under the plate on the glass plate at the same time. Bubbles of this size are still considered to be problems upstream of the kiln. The appearance of such bubbles is generally caused by slight changes in the temperature of the kiln and the low bubbling frequency of the bubbler 6. At this time, it is necessary to observe the temperature change curve in the temperature control system of the kiln, increase the natural gas release of the spray gun in the melting part 1 of the kiln and the combustion-supporting air volume of the small furnace 4, so that the temperature at the bubbler 6 rises to the standard temperature of 1530°C; at the same time, appropriately increase the bubbling frequency. The original bubbling frequency is 7s / time, and it is adjusted to 6s / time. After the production line has been running for a period of time, the bubble defects of the glass are detected by the automatic detection and inspection machine. It is found that the secondary bubbles on the plate, bubbles in the plate and bubbles under the plate are all eliminated, which proves that the measures of this embodiment can indeed control the secondary bubbles on the plate, bubbles in the plate and bubbles under the plate.

[0033] Example 4

[0034] When the automatic inspection machine of the production line detects the existence of three-level bubbles on the glass plate, bubbles in the plate and bubbles under the plate, it is necessary to consider the temperature change at the kiln bubbler 6, the bubbling frequency of the bubbler 6 and the temperature change of the clarification part 2. Such bubbles are generally caused by large changes in the temperature inside the kiln and too low bubbling frequency of the bubbler 6. At this time, it is necessary to observe the temperature change curve in the kiln temperature control system, increase the natural gas release of the spray gun in the melting part 1 of the kiln and the combustion-supporting air volume of the small furnace 4, so that the temperature at the bubbler 6 rises to the standard temperature of 1530℃; at the same time, appropriately increase the bubbling frequency, the original bubbling frequency is 7s / time, and adjust it to 6s / time; and turn on the LPG combustion system 7 of the kiln cooling part 3, and control the temperature of the cooling part at about 1150℃ to ensure that the temperature of the clarification part 2 does not lose, so that the temperature of the clarification part 2 approaches 1530℃. After the production line had been running for a period of time, the bubble defects of the glass were detected by an automatic detection and inspection machine, and it was found that the three-level bubbles on the board, bubbles in the board, and bubbles under the board were all eliminated, proving that the measures of this embodiment can indeed control the three-level bubbles on the board, bubbles in the board, and bubbles under the board.

[0035] Although the present invention has been described in detail by referring to the accompanying drawings and in combination with the preferred embodiments, the present invention is not limited thereto. Without departing from the spirit and essence of the present invention, a person of ordinary skill in the art may make various equivalent modifications or substitutions to the embodiments of the present invention, and these modifications or substitutions shall be within the scope of the present invention. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, and all of these shall be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. Ultra-thin glass bubble defect control method, It is characterized in that The following steps are involved: S1 Control of open bubbles on the plate: When the diameter of the open bubbles on the plate is ≤2.5 μm, increase the natural gas release of the spray gun in the melting part (1) of the kiln and the combustion-supporting air volume of the small furnace (4) to raise the temperature at the bubbler (6) to the standard temperature, which can improve this type of bubble defect; S2 controls bubbles on the board, bubbles in the board, and bubbles under the board: S21 When the bubble diameter is greater than 2.5 μm, increasing the bubbling frequency of the bubbler (6) can improve this type of bubble defect; S22 When 1.5 μm < bubble diameter ≤ 2.5 μm, increase the natural gas release rate of the spray gun in the melting part (1) of the furnace and the combustion-supporting air volume of the small furnace (4) to raise the temperature at the bubbler (6) to the standard temperature; at the same time, increase the bubbling frequency of the bubbler (6) to improve this type of bubble defect; S23 When the bubble diameter is ≤1.5 μm, the natural gas release amount of the spray gun in the melting section (1) of the kiln and the combustion-supporting air volume of the small furnace are increased to raise the temperature at the bubbler (6) to the standard temperature; at the same time, the bubbling frequency of the bubbler (6) is increased; and the LPG combustion system (7) of the kiln cooling section (3) is turned on to raise the temperature of the cooling section (3) to ensure that the temperature of the kiln clarification section (2) does not lose, thereby improving this type of bubble defect; S2 Control of open bubbles under the board: If the open bubbles under the board appear only once or disappear after a few times, no treatment is required; if such bubbles are continuously generated, find the leak point of the tin bath, drill a hole at the bottom of the tin bath to the leak point, and add filler into the leak point to improve such bubble defects; Among them, the standard temperature refers to the standard production temperature that the melting part of the kiln needs to reach during glass production.

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