Overflow brick and method for controlling the thickness of its thin sheet molding

Abstract

A method for controlling the thickness of a thin sheet formed by an overflow brick includes: S1 obtaining a free flow thickness distribution and a free flow velocity distribution of the glass overflow on the overflow surface of the overflow brick through simulation; S2 calculating an equivalent drawing velocity distribution of the overflow guide plate and a critical equivalent drawing velocity of the overflow guide plate; S3 calculating an equivalent drawing thickness distribution and a formed thickness distribution of the glass overflow; S4 calculating an extreme thickness difference of the formed glass substrate; S5 changing current parameters and repeating S1 to S4 if the extreme thickness difference of the formed glass substrate is greater than or equal to a preset threshold; and S6 processing the overflow brick and producing glass substrates according to the current parameters if the extreme thickness difference of the formed glass substrate is less than or equal to the preset threshold. This method effectively solves the problem of variation in the formed thickness of the glass substrate and increases the production margin in design, allowing the formed glass substrate thickness to meet requirements, further reducing the complexity of process adjustment requirements and further maintaining the stability of the production line.

Description

Technical Field

[0001] The present invention belongs to the field of glass substrate manufacturing, Overflow Brick and relates to a thin plate forming thickness control method thereof.

Background Art

[0002] The glass substrates used in the general flat panel display manufacturing fields such as TFT-LCD (Thin Film Transistor Display), PDP (Plasma Display Panel), etc. are manufactured by the overflow down-draw method. In the forming process, the molten glass melted in the glass melting furnace is supplied to the molten overflow down-draw forming device for manufacturing. For the manufacture of displays, larger glass substrates are increasingly required for improving production efficiency and reducing costs. However, the larger the glass substrate, the more difficult the production becomes, and the quality control of the glass substrate becomes more complicated.

[0003] Overflow Brick is one of the core members of the glass substrate manufacturing and forming device. Among them, the control of the thickness uniformity of the glass substrate is one of the particularly important process technologies. Taking a 0.7 mm glass substrate as an example, its thickness variation needs to be within about 20 um or 30 um, Overflow Brick is that the quality of the structural design and the size of the process margin are one of the important factors for the stability of the forming process. To avoid instantaneous changes in the mass distribution and thermal distribution caused by the glass, Overflow Brick control the sideboard flow rate and balance at the far end and near end of , and adjust the forming process by adjusting the flow rate, temperature, etc. according to the overall initial thickness distribution. That is, using the overflow down-draw method, strict requirements are imposed on the properties such as stress, warping, thickness, and bending of the plate material, and a glass substrate with stable performance is manufactured. The control of the thickness and its consistency of the glass substrate is one of the very important design and process technologies. Since the glass substrate is very thin, any process variation including the air flow and thermal field in the production process will affect the thickness of the formed glass substrate, and further have an adverse effect on the quality of the display. Overflow BrickIn design, it is necessary to consider the influence of these complex factors on the thickness distribution of the glass substrate, that is, to increase the production margin in the design, and in contrast to this, the overall thickness distribution of the glass substrate Thickness range Determine <15μm

[0004] Ensuring that the thickness distribution of the glass substrate meets the requirements is one of the critical process control and quality control items in glass substrate manufacturing, and is one of the most difficult problems in glass substrate production. [Overview of the project]

[0005] The present invention overcomes the drawback in the above-mentioned conventional technology, in which the thickness distribution of the glass substrate cannot meet the usage requirements after the glass substrate is produced. Overflow Brick The objective is to provide a method for controlling the thickness of thin sheet metal forming.

[0006] To achieve the above objectives, the present invention is realized by employing the following technical solutions. Overflow Brick A method for controlling the thickness of a thin sheet during forming, Overflow Brick The overflow surface is divided into multiple equal parts by length, Overflow Brick According to the structural parameters, glass material parameters, and flow parameters, Overflow Brick Glass overflow on the overflow surface In each of the equally divided parts free flow thickness Sato free flow velocity degree S1 obtained through simulation, Glass substrate design thickness and glass overflow In each of the equally divided parts free flow thickness Sani Therefore, the overflow guide plate In each of the equally divided parts Equivalent stretching speed degree Obtain and glass overflow In each of the equally divided parts free flow velocity Each time Therefore, S2 is used to obtain the critical equivalent stretching rate of the overflow guide plate, The overflow guide plate is divided into multiple equal parts by width, and the glass overflow In each of the equally divided parts free flow velocity degree and free flow thickness Sakyu and overflow guide plate In each of the equally divided parts Equivalent stretching speed degree and According to the critical equivalent stretching rate, glass overflow In each of the equally divided parts equivalent stretched thickness Sato Molding thickness Sawo The S3 to be retrieved, Glass overflow In each of the equally divided parts Molding thickness Sani Therefore, the molded glass substrate Thickness range S5 to obtain, Molded glass substrate Thickness range >If the threshold is set in advance, in S1 Overflow Brick Repeat steps S1 to S5 by changing the structural parameters, glass material parameters, or glass flow parameters. Thickness of molded glass substrate range If the threshold is ≤ a pre-set threshold, then in S1 Overflow Brick According to the structural parameters, glass material parameters, or glass flow parameters Overflow Brick This includes S6, which performs processing and production of glass substrates.

[0007] Further improvements to the present invention are as follows: The specific method of S1 is as follows: Three-dimensional software Overflow Brick S101 establishes a geometric model of the fluid portion. Using mesh generation software Overflow Brick S102 establishes a finite element mesh model. Using fluid dynamics software, Overflow Brick S103, which takes the structural parameters, glass material parameters, and flow rate parameters as input and performs a simulation calculation, Overflow Brick The overflow surface is divided into multiple equal parts by length, and the glass overflow is calculated according to the simulation results. In each of the equally divided parts free flow thickness Sato free flow velocity degree This includes obtaining S104.

[0008] The specific method of S2 is as follows: The designed thickness of the glass substrate and the In each of the equally divided parts free flow thickness of the glass overflow Sani Therefore, according to Equation (1) of the overflow guide plate In each of the equally divided parts S201 for obtaining TIFF0007854387000001.tif10153, JPEG0007854387000002.jpg14170 where JPEG0007854387000003.jpg10170 is the designed thickness of the glass substrate, JPEG0007854387000004.jpg11170JPEG0007854387000005.jpg11170 is the speed of the overflow guide plate, JPEG0007854387000006.jpg12170JPEG0007854387000007.jpg11170 is the free flow thickness of the glass overflow, JPEG0007854387000008.jpg11170 of the overflow guide plate JPEG0007854387000009.jpg11170 is S201, and of the glass overflow In each of the equally divided parts free flow velocity Each time Therefore, according to Equation (2), for the overflow guide plate S202 for obtaining JPEG0007854387000010.jpg11170, JPEG0007854387000011.jpg11170 where JPEG0007854387000012.jpg10170 is the critical factor, JPEG0007854387000013.jpg11170JPEG0007854387000014.jpg10170 is the minimum free flow velocity, and includes S202 which is JPEG0007854387000015.jpg11170.

[0009] In the said S201 JPEG0007854387000016.jpg is obtained by formula (3), JPEG0007854387000017.jpg17170In formula, JPEG0007854387000018.jpg11170 Overflow Brick This is the amount withdrawn, JPEG0007854387000019.jpg11170JPEG0007854387000020.jpg9170This is the density of glass, JPEG0007854387000021.jpg12170JPEG0007854387000022.jpg10170 Overflow Brick This is the length of the overflow surface, JPEG0007854387000023.jpg10170JPEG0007854387000024.jpg10170This is the width of the overflow guide plate. JPEG0007854387000025.jpg10170JPEG0007854387000026.jpg10170This is the design thickness of the glass substrate. The files are JPEG0007854387000027.jpg9170 and JPEG0007854387000028.jpg10170.

[0010] The specific method of S3 is as follows: According to equation (4), the glass substrate S301 retrieves JPEG0007854387000029.jpg10170, JPEG0007854387000030.jpg14170In formula, JPEG0007854387000031.jpg11170 is the width of the overflow guide plate. JPEG0007854387000032.jpg10170JPEG0007854387000033.jpg11170 Overflow Brick This is the length of the overflow surface, S301, JPEG0007854387000034.jpg10170 According to equation (5), glass overflow S302 retrieves JPEG0007854387000035.jpg11170, JPEG0007854387000036.jpg14170In formula, JPEG0007854387000037.jpg10170 This is the critical equivalent stretching rate of the overflow guide plate. JPEG0007854387000038.jpg11170JPEG0007854387000039.jpg10170This is the free flow velocity of glass overflow. JPEG0007854387000040.jpg11170JPEG0007854387000041.jpg11170 Overflow guide plate In each of the equally divided parts Equivalent stretching speed degrees can be, JPEG0007854387000042.jpg11170JPEG0007854387000043.jpg10170This is the free flow thickness of glass overflow. JPEG0007854387000044.jpg11170 Glass overflow S302, whose filename is JPEG0007854387000045.jpg11170. According to equation (6) Overflow Brick Different positions on the overflow surface S303 retrieves JPEG0007854387000046.jpg11170, and the calculation formula is as follows: JPEG0007854387000047.jpg13170In formula, JPEG0007854387000048.jpg12170 Overflow Brick This is the average equivalent stretching thickness on the overflow surface, JPEG0007854387000049.jpg10170JPEG0007854387000050.jpg11170 Overflow Brick This is the amount withdrawn, S303, whose filename is JPEG0007854387000051.jpg11170. According to equation (7), glass overflow S304 retrieves JPEG0007854387000052.jpg11170, JPEG0007854387000053.jpg18170In formula, JPEG0007854387000054.jpg9170 This is the density of glass, The filename is JPEG0007854387000055.jpg11170. JPEG0007854387000056.jpg10170 Overflow guide plate speed, S304, which is JPEG0007854387000057.jpg11170, and The overflow guide plate is divided into multiple equal parts by width, and the glass overflow is divided according to S301~S304. In each of the equally divided parts equivalent stretched thickness Sato Molding thickness Sawo This includes acquiring S305.

[0011] The specific method of S5 is as follows: Glass overflow In each of the equally divided parts Molding thickness Sani Therefore, the molded glass substrate is obtained by equation (8). This includes obtaining TIFF0007854387000058.tif10170, JPEG0007854387000059.jpg12170In formula, JPEG0007854387000060.jpg9170 is a glass overflow. In each of the equally divided parts Molding thickness Sade be.

[0012] Compared to conventional technologies, the present invention has the following beneficial effects. This method first performs simulation calculations through simulation, and then a series of Overflow Brick Glass overflow on the overflow surface In each of the equally divided parts free flow thickness Sato free flow velocity degreeObtain, and then the overflow guide plate related to the guide plate or traction speed In each of the equally divided parts Equivalent stretching speed extent Critical equivalent extension of overflow guide plate Stretch Calculate and a series of glass overflows In each of the equally divided parts equivalent stretched thickness Sato Molding thickness Sawo Calculate and finally, the molded glass substrate Thickness range Calculate, In each of the equally divided parts Molding effect thickness Range of thickness Evaluate whether it meets the design objectives, and if it does not, Overflow Brick The amount drawn out, the viscosity of the molded glass, and Overflow Brick Structural parameters, for example Overflow Brick Prioritize adjusting one or more combinations of the following: the groove entrance width, groove entrance height, overflow weir inclination angle, overflow surface length, and the curve of the overflow groove bottom. In each of the equally divided parts Molding effect thickness Range of thickness Until the design objectives are met, Overflow Brick This invention performs processing and production of glass substrates. This invention effectively solves the problem of variations in the molding thickness of glass substrates, and by increasing the production margin in the design, the molding thickness of the glass substrate can meet the requirements, further reducing the complexity requirements of process adjustments and further maintaining the stability of the production line. [Brief explanation of the drawing]

[0013] [Figure 1] This is a schematic diagram of the overflow system structure. [Figure 2] This is a schematic diagram of an overflow downdraw structure. [Figure 3] This is a schematic diagram of the external structure of an overflow brick. [Figure 4] This is a schematic diagram of the structure of the overflow groove within the overflow brick. [Figure 5] This is a flowchart of the method for controlling the thin sheet thickness of an overflow brick according to the present invention. [Figure 6] This is a graph showing the results of an embodiment of the free flow thickness in each equally divided portion according to the present invention. [Figure 7] This is a graph showing the results of an embodiment of the free flow velocity in each equally divided portion according to the present invention. [Figure 8] This is a graph showing the results of an example of the equivalent stretching rate in each equally divided portion according to the present invention. [Figure 9] This is a graph showing the results of the equivalent stretch thickness in each equally divided portion according to the present invention. [Figure 10] This is a graph showing the results of an example of the molding thickness in each equally divided portion according to the present invention. [Modes for carrying out the invention]

[0014] To enable those skilled in the art to better understand the means of the present invention, the technical methods in the embodiments of the present invention are described below in clear and complete terms, with reference to the drawings of the embodiments. Of course, the embodiments described are not all embodiments, but only a selection of embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments that those skilled in the art can obtain without creative effort are all within the scope of the present invention.

[0015] As necessary for explanation, terms such as “First,” “Second,” etc., in the specification, claims, and drawings above are used (if present) to distinguish similar objects and are not used to describe a particular order or sequence. It should be understood that data used in this manner may be interchangeable under appropriate circumstances, and that embodiments of the invention described herein may be carried out in an order other than that illustrated or described herein. Furthermore, the terms “includes” and “has” and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or apparatus that includes a series of steps or units does not have to be limited to those steps or units explicitly mentioned, and may include other steps or units that are not explicitly mentioned or are specific to those processes, methods, products, or apparatus.

[0016] The present invention will be described in more detail below, using the drawings as a reference. Referring to Figure 1, the overflow system Overflow Brick It is constructed by connecting 1 and the molten glass supply device 3. Overflow Brick An overflow groove 2 is made inside 1. Overflow Brick The bottom of 1 is Overflow Brick In the case of manufacturing the glass substrate by melt overflow, the molding process involves supplying molten glass melted in a glass melting furnace to a molten glass supply device 3 in a melt overflow molding apparatus, along the overflow groove 2. Overflow Brick Overflow through both sides of 1, Overflow Brick A glass substrate is formed from below the base 4 of 1. Referring to Figure 2, which is a schematic diagram of an overflow downdraw structure, the guide plate serves as the forming base for the glass substrate, and in the process of downdraw forming of the glass substrate, the formed glass substrate 5 moves downward along the downdraw direction 6 of the glass substrate. In downdraw forming, the molten glass gradually forms a glass substrate along the glass guide plate, and in the width direction, the thickness of the glass substrate is thin and uniform from the center to both ends of the glass substrate, and the thickness of the glass substrate forms from the center to both sides. Referring to Figures 3 and 4, Figure 3 is used in the manufacturing of a glass substrate by the overflow downdraw method. Overflow Brick Figure 4 is a schematic diagram of the external structure. Overflow Brick This is a schematic diagram of the internal overflow groove structure, and in the drawing, Overflow Brick of JPEG0007854387000061.jpg11170JPEG0007854387000062.jpg12170 shows important structural design dimensions, and in actual production, Overflow Brick It goes without saying that this includes all of the above parameters, and further includes the curve of the bottom of the overflow groove.

[0017] Refer to Figure 5, and the present invention Overflow Brick The method for controlling the thickness of thin sheet forming includes the following steps.

[0018] Using specialized fluid software such as S1 and FLUENT, we perform overflow simulations. Overflow Brick Glass overflow on the overflow surface In each of the equally divided parts TIFF0007854387000063.tif11170 and Retrieve TIFF0007854387000064.tif11170. Specifically, Using S101, CAD software, or PROE, Overflow Brick Establish a geometric model of the fluid portion. S102, to avoid software limitations, use mesh generation software. Overflow Brick Establish a finite element mesh model. Using specialized fluid dynamics software such as S103 and FLUENT, the simulation calculation is performed by inputting relevant conditions such as glass material parameters including density, viscosity, and surface tension, as well as glass flow parameters. S104, Overflow Brick The length L of the overflow surface is divided into N equal parts, such as 50, and a series of glass overflows are generated according to the simulation results. In each of the equally divided parts TIFF0007854387000065.tif11170 and Obtain TIFF0007854387000066.tif11170, and as shown in Table 1, [Table 1] TIFF0007854387000067.tif40170 Glass overflow In each of the equally divided parts TIFF0007854387000068.tif11170 is a result obtained under different simulation conditions, and different Overflow Brick This may be based on the amount of material drawn out, or on the viscosity of different glass materials, allowing for comparison of the effects under different conditions.

[0019] S2, equivalent extension speed related to the guide plate or traction speed or JPEG0007854387000069.jpg10170 and critical equivalent stretching rate or Calculate JPEG0007854387000070.jpg10170. Specifically, S201, guide plate or overflow guide plate related to traction speed In each of the equally divided parts Calculate TIFF0007854387000071.tif11170, and the calculation formula is as shown in formula (1): JPEG0007854387000072.jpg14170In formula, JPEG0007854387000073.jpg11170 This is the design thickness of the glass substrate. JPEG0007854387000074.jpg10170JPEG0007854387000075.jpg10170 Overflow guide plate speed, JPEG0007854387000076.jpg11170JPEG0007854387000077.jpg9170This is the free flow thickness of glass overflow. The calculation formulas for JPEG0007854387000078.jpg9170, JPEG0007854387000079.jpg11170, and JPEG0007854387000080.jpg11170 are as follows: JPEG0007854387000081.jpg18170In formula, JPEG0007854387000082.jpg11170 Overflow Brick This is the amount withdrawn, JPEG0007854387000083.jpg11170JPEG0007854387000084.jpg10170This is the density of glass, JPEG0007854387000085.jpg12170JPEG0007854387000086.jpg10170 Overflow Brick This is the length of the overflow surface, JPEG0007854387000087.jpg9170JPEG0007854387000088.jpg10170This is the width of the overflow guide plate. JPEG0007854387000089.jpg10170JPEG0007854387000090.jpg11170S202, guide plate or overflow guide plate related to traction speed The calculation for JPEG0007854387000091.jpg10170 is as shown in equation (3): JPEG0007854387000092.jpg12170In formula, JPEG0007854387000093.jpg10170 is a critical factor, and generally JPEG0007854387000094.jpg11170JPEG0007854387000095.jpg10170 This is the minimum free flow velocity of glass overflow, JPEG0007854387000096.jpg11170JPEG0007854387000097.jpg11170

[0020] S3, glass overflow Calculate JPEG0007854387000098.jpg11170, specifically, S301, glass substrate The calculation for JPEG0007854387000099.jpg11170 is as shown in equation (4): JPEG0007854387000100.jpg13170In formula, JPEG0007854387000101.jpg10170 is the width of the overflow guide plate. JPEG0007854387000102.jpg10170JPEG0007854387000103.jpg11170 Overflow Brick This is the length of the overflow surface, JPEG0007854387000104.jpg10170S302, glass overflow The calculation for JPEG0007854387000105.jpg11170 is as shown in equation (5): JPEG0007854387000106.jpg13170In formula, JPEG0007854387000107.jpg11170 This is the critical equivalent stretching speed or auxiliary traction speed. JPEG0007854387000108.jpg11170JPEG0007854387000109.jpg11170This is the free flow velocity of glass overflow. JPEG0007854387000110.jpg10170JPEG0007854387000111.jpg10170 This is equivalent stretching speed or auxiliary traction speed. JPEG0007854387000112.jpg11170JPEG0007854387000113.jpg10170This is the free flow thickness of glass overflow. JPEG0007854387000114.jpg10170JPEG0007854387000115.jpg10170 This is a shrinkage factor of the glass substrate, JPEG0007854387000116.jpg11170S303, Overflow Brick Different positions on the overflow surface The calculation for JPEG0007854387000117.jpg11170 is as shown in equation (6): JPEG0007854387000118.jpg13170In formula, JPEG0007854387000119.jpg10170 This is the equivalent stretched thickness of glass overflow. JPEG0007854387000120.jpg11170JPEG0007854387000121.jpg11170 Overflow Brick This is the average equivalent stretching thickness on the overflow surface, JPEG0007854387000122.jpg10170JPEG0007854387000123.jpg11170This is the amount extracted. JPEG0007854387000124.jpg11170S304, glass overflow The calculation for JPEG0007854387000125.jpg11170 is as shown in equation (7): JPEG0007854387000126.jpg16170In formula, JPEG0007854387000127.jpg9170 Overflow Brick This is the equivalent glass flow rate at different positions on the overflow surface. JPEG0007854387000128.jpg10170JPEG0007854387000129.jpg9170This is the density of glass, JPEG0007854387000130.jpg11170JPEG0007854387000131.jpg10170This is the width of the overflow guide plate. JPEG0007854387000132.jpg10170JPEG0007854387000133.jpg10170 Guide plate speed, JPEG0007854387000134.jpg11170S305, Divide JPEG0007854387000135.jpg11170 into N equal parts (e.g., 50 parts) and, according to the above calculation results, a series of glass overflows In each of the equally divided parts Obtain JPEG0007854387000136.jpg11170 and refer to Table 2. TIFF0007854387000137.tif42170

[0021] S4, molded glass substrate Calculate TIFF0007854387000138.tif10170, and the calculation formula is as shown in formula (8): JPEG0007854387000139.jpg12170

[0022] S5, the molding effect of the molded glass substrate In each of the equally divided parts thick Range of thickness However, we evaluate whether the design objectives are met, and specifically, If the design objectives are met, in S1 Overflow Brick According to the structural parameters, glass material parameters, or glass flow parameters Overflow Brick We perform processing and production of glass substrates. If the design objectives are not met, Overflow Brick of Adjust JPEG0007854387000140.jpg11170, Overflow Brick Prioritize adjusting the glass viscosity, Overflow Brick The structural parameters are optimized and adjusted, and the structural parameters are Overflow Brick of JPEG0007854387000141.jpg11170 Overflow Weir JPEG0007854387000142.jpg12170 Overflow surface This includes JPEG0007854387000143.jpg11170 and one or more combinations of the curves at the bottom of the overflow groove, etc., and then returns to S1.

[0023] Refer to Figures 6-10, which are references according to the present invention. Overflow Brick This is an example of a method for controlling the thickness of thin sheet metal forming. Overflow Brick Optimized JPEG0007854387000144.jpg11170259.254mm, JPEG0007854387000145.jpg is 10170200.032mm, and the overflow surface JPEG0007854387000146.jpg is 101702973mm, and is an overflow weir. The file is JPEG0007854387000147.jpg111706.0°, JPEG0007854387000148.jpg is 1117020 tons / day, Thickness range The target is smaller than 70 μm. Figure 6 shows the results of this embodiment. In each of the equally divided parts free flow thickness Samo This is a diagram, and Figure 7 shows the result of this embodiment. In each of the equally divided parts free flow velocity degree model This is a diagram, and Figure 8 shows an embodiment. In each of the equally divided parts Equivalent stretching speed degree model This is a diagram, and Figure 9 shows the result of this embodiment. In each of the equally divided parts equivalent stretched thickness Samo This is a diagram, and Figure 10 shows the In each of the equally divided parts Molding thickness Samo This is a diagram of the formula, and in this embodiment Thickness range The value is 68.52 μm, which perfectly meets the design target.

[0024] The above is merely to explain the technical concept of the present invention and does not limit the scope of protection of the present invention. Any modification made to the technical proposal in accordance with the technical concept of the present invention falls within the scope of protection of the claims of the present invention. [Explanation of Symbols]

[0025] 1- Overflow Brick 2- Overflow groove 3. Molten glass supply device 4- Overflow Brick base 5. Molded glass substrate 6. Down-draw direction of the glass substrate

Claims

[Claim 1] A method for controlling the thickness of thin sheet forming of overflow bricks, S1 involves dividing the overflow surface of the overflow brick into multiple equal parts by length, and obtaining the free flow thickness and free flow velocity in each of the divided parts of the glass overflow on the overflow surface of the overflow brick by simulation, according to the structural parameters of the overflow brick, the material parameters of the glass, and the flow rate parameters. S2 obtains the equivalent stretching rate in each equally divided portion of the overflow guide plate according to the design thickness of the glass substrate and the free flow thickness in each equally divided portion of the glass overflow, and obtains the critical equivalent stretching rate of the overflow guide plate according to the free flow velocity in each equally divided portion of the glass overflow, S3 divides the overflow guide plate into multiple equal parts by width, and obtains the equivalent stretched thickness and molding thickness in each of the equally divided parts of the glass overflow according to the free flow velocity and free flow thickness in each equally divided part of the glass overflow, and the equivalent stretched velocity and critical equivalent stretched velocity in each equally divided part of the overflow guide plate. S4 obtains a range of thickness for the molded glass substrate according to the molding thickness in each equally divided portion of the glass overflow, If the thickness range of the molded glass substrate is greater than a preset threshold, the structural parameters of the overflow brick, the material parameters of the glass, or the flow rate parameters of the glass are changed in S1, and S1 to S4 are repeated. If the thickness range of the molded glass substrate is less than or equal to the preset threshold, S5 includes processing the overflow brick and producing the glass substrate according to the structural parameters of the overflow brick, the material parameters of the glass, or the flow rate parameters of the glass in S1. The structural parameters of the overflow brick include the groove inlet width, groove inlet height, inclination angle of the overflow weir, length of the overflow surface, and curve of the overflow groove bottom; the material parameters of the glass include density, viscosity, and surface tension; and the flow rate parameters of the glass include the amount of the overflow brick drawn out. The specific method of S1 is as follows: S101 establishes a geometric model of the fluid portion of the overflow brick using three-dimensional software, S102 establishes a finite element mesh model of the overflow brick using mesh generation software, S103 involves using fluid software to input the structural parameters of the overflow brick, the material parameters of the glass, and the flow rate parameters, and performing a simulation calculation, and S104 includes dividing the overflow surface of the overflow brick into multiple equal parts by length, and obtaining the free flow thickness and free flow velocity in each of the divided parts of the glass overflow according to the simulation results, The specific method of S2 is as follows: S201 obtains the equivalent stretching rate Ve distribution in each equally divided portion of the overflow guide plate according to the design thickness of the glass substrate and the free flow thickness in each equally divided portion of the glass overflow, by formula (1), During the ceremony, T is the design thickness of the glass substrate, in units of mm; Vd is the overflow guide plate speed, in units of mm / min; Ts is the free flow thickness of the glass overflow, in units of mm; and the equivalent stretching speed Ve of the overflow guide plate is in units of m / s. The overflow guide plate speed Vd is obtained by equation (3), In the formula, Q is the amount of the overflow brick drawn out, in units of kg / hr; ρ is the density of the glass, in units of kg / m³; and L is the length of the overflow surface of the overflow brick, in units of mm. S201 is the width of the overflow guide plate, in units of mm, T is the design thickness of the glass substrate, in units of mm, and the overflow guide plate speed Vd is in units of mm / min, and S202, in which the critical equivalent stretching velocity Vc of the overflow guide plate is obtained by equation (2) according to the free flow velocity in each equally divided portion of the glass overflow, In the equation, Kc is a critical factor, and Kc = 1, V ｓｍｉｎ S202 is the minimum free flow velocity, with units of m / s, and Vc has units of m / s, and includes The specific method of S3 is as follows: S301 is a method for obtaining the shrinkage factor Cs of the glass substrate by formula (4), During the ceremony, S301 is the width of the overflow guide plate, in units of mm, and L is the length of the overflow surface of the overflow brick, in units of mm. S302, in which the equivalent stretched thickness Te of the glass overflow is obtained by formula (5), In the formula, Vc is the critical equivalent stretching rate of the overflow guide plate, in units of m / s; Vs is the free flow velocity of the glass overflow, in units of m / s; Ve is the equivalent stretching rate in each equally divided portion of the overflow guide plate, in units of m / s; Ts is the free flow thickness of the glass overflow, in units of mm; and the equivalent stretching thickness Te of the glass overflow is in units of mm. S303 obtains the equivalent glass flow rate Qe at different positions on the overflow surface of the overflow brick by formula (6), wherein the calculation formula is as follows: During the ceremony, S303 is the average equivalent stretch thickness on the overflow surface of the overflow brick, in units of mm, and Q is the amount of the overflow brick drawn out, in units of kg / hr. Formation thickness T of glass overflow with average equivalent stretching thickness according to equation (7) ｆ S304 to obtain, In the formula, ρ is the density of the glass, and its unit is kg / m³. ３ S304 is such that Vd is the overflow guide plate speed, and the unit is mm / min, and S305 includes dividing the overflow guide plate into multiple equal parts by width and obtaining the equivalent stretched thickness and the molding thickness in each of the equally divided parts of the glass overflow according to S301 to S304, The specific method of S4 is as follows: The process involves obtaining the extreme thickness difference Δ of the molded glass substrate according to the molding thickness in each equally divided portion of the glass overflow using formula (8), During the ceremony, This is the molding thickness in each equally divided portion of the glass overflow. A method for controlling the thickness of thin sheet metal formed overflow bricks, characterized by the above.

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