Tin bath for producing image-deformation-free ultra-white special float glass

Abstract

The invention provides a tin bath for producing image-deformation-free ultra-white special float glass, and belongs to the technical field of float kilns. The tin bath comprises a wide section and a narrow section, the tin bath is divided into 22 shells in the glass traction direction, 1-13 shells are located in the wide section, 15-22 sections are located in the narrow section, 14 shells are transition areas of the wide section and the narrow section, the ninth shell area, the eleventh shell area, the twelfth shell area and the 22 shell area are each provided with a graphite blocking ridge set, the eleventh shell area, the thirteenth shell area and the fifteenth shell area are each provided with a graphite blocking ridge, and the ninth shell area, the eleventh shell area, the thirteenth shell area and the fifteenth shell area are each provided with a graphite blocking ridge. The graphite blocking ridge set comprises two first blocking strips extending from the side walls of the tin bath to the center of the tin bath, the graphite blocking ridge comprises a second blocking strip transversely arranged between the two side walls of the tin bath, and the first blocking strips and the second blocking strip are located at the bottom of the tin bath and located below the liquid level of the tin bath. The lower surface of one end, close to the tin bath side wall, of the first barrier strip is provided with a notch, and the side face, close to the tin bath glass traction direction, of the second barrier strip is a corrugated face. The method has the advantages of being capable of reducing tin flow lines and the like.

Description

Technical Field

[0001] The invention belongs to the technical field of float furnaces and relates to a tin bath for producing ultra-white special float glass without image deformation. Background Art

[0002] The present invention provides a tin bath for producing ultra-clear, special float glass without image distortion, and its use method, belonging to the technical field of float glass production. The tin bath is an important forming thermal equipment in float glass production, comprising a wide section, a contraction section, and a narrow section connected in sequence. High-temperature molten glass flows into the tin bath, which uses molten tin as a floatation medium. Under the combined effects of gravity, surface tension, the buoyancy of the tin, and the pull of the molten tin, the molten glass forms a glass ribbon of a certain thickness. After the glass ribbon is formed, it enters an annealing lehr for stress control and cooling. After annealing, the glass enters the finished product cutting section to produce products of the desired specifications.

[0003] Problems with existing technology: Ultra-clear specialty float glass is often used in high-end glass curtain wall projects, which requires that the original glass sheet be free of image distortion. Otherwise, the installed curtain wall glass will appear visually distorted. Current tin bath production technology can cause distortion in the original glass sheet due to the following factors.

[0004] 1) The molten tin that acts as a float will flow in the tin bath due to the lateral temperature gradient, longitudinal temperature gradient and mechanical force generated by the operation of the glass ribbon. The intersection of cold and hot tin liquids, turbulence or eddy currents of the tin liquid will form tin flow pattern deformation on the bottom surface of the glass.

[0005] 2) Large-tonnage tin baths require a cooling water drum at the narrow end to regulate the temperature of the glass, ensuring it remains within a reasonable range of 580-620°C upon exiting the bath. The existing water drum structure can exacerbate lateral temperature differences in the glass, resulting in surface ripples and deformation.

[0006] 3) The space water bag used in the narrow section is used on the upper part of the glass. The upper surface of the glass is cooled first. At this time, the temperature difference between the upper and lower surfaces of the glass will cause the glass to deform. Summary of the Invention

[0007] The purpose of the present invention is to provide a tin bath for producing ultra-white special float glass without image distortion in view of the above problems existing in the prior art. The technical problem to be solved by the present invention is how to reduce the backflow of tin liquid and alleviate the tin flow pattern of the glass.

[0008] The objectives of the present invention can be achieved through the following technical solutions: A tin bath for producing ultra-white special float glass without image distortion, the tin bath comprising a wide section and a narrow section, the tin bath being divided into 22 sections along the glass drawing direction, wherein sections 1 to 13 are located in the wide section, sections 15 to 22 are located in the narrow section, and section 14 is a transition area between the wide section and the narrow section, characterized in that a graphite baffle group is respectively provided in the 9-bar area, the 11-bar area, the 12-bar area, and the 22-bar area, and a graphite baffle is respectively provided in the 11-bar area, the 13-bar area, and the 15-bar area, the graphite baffle group comprising two first baffles extending from the side wall of the tin bath toward the center of the tin bath, the graphite baffle comprising a second baffle laterally arranged between the two side walls of the tin bath, the first baffle and the second baffle being both located at the bottom of the tin bath, the first baffle and the second baffle being both located below the liquid level of the tin bath, the lower surface of the first baffle at one end close to the side wall of the tin bath having a notch, and the side surface of the second baffle close to the glass drawing direction of the tin bath having a corrugated surface.

[0009] Furthermore, the inner ends of the first blocking bars in the 9-beta area, the 11-beta area, and the 12-beta area face the glass pulling direction, and the outer ends of the first blocking bars in the 22-beta area face the glass pulling direction.

[0010] Furthermore, the area 22 has an expansion portion, the width of the tin bath gradually increases from the expansion portion to the end of the tin bath, and the first barrier strip of the area 22 is located at the expansion portion.

[0011] Furthermore, the distance between the graphite retaining wall in the 11-bei area and the tin liquid surface is smaller than that between the graphite retaining wall in the 13-bei area and the tin liquid surface, and the distance between the graphite retaining wall in the 13-bei area and the tin liquid surface is smaller than that between the graphite retaining wall in the 15-bei area and the tin liquid surface.

[0012] Furthermore, the narrow section is provided with a plurality of cooling water bags, which include two cooling water pipes symmetrically distributed on the tin bath, the water inlet and outlet ends of the cooling water pipes both extending beyond the side wall of the tin bath, and the cooling water pipe has a serpentine cooling section above the glass plate, the inner end of the cooling section is located at the center line of the tin bath, and the distance between each cooling section on the same side of the tin bath and the side wall of the tin bath gradually increases from the head end to the end of the narrow section.

[0013] Three graphite barriers are set at the 11th, 13th and 15th bends of the tin bath respectively. The graphite barriers are higher than the bottom surface of the tin bath and are 15 to 25 mm away from the surface of the tin liquid. They can effectively reduce the backflow of low-temperature tin liquid from the narrow end to the wide end. In addition, since these three graphite barriers are stepped, the closer to the end of the tin bath, the lower the graphite barrier is, so the backflowing tin liquid is gradually blocked in sequence, slowing down the speed and intensity of the tin liquid backflow. Moreover, the graphite barrier is a second baffle with a corrugated flow-blocking surface, which can convert the part of the tin liquid flowing in the direction of glass traction into a lateral flow of tin liquid, slowing down the tin liquid backflow.

[0014] Graphite baffle groups are set at the 9th, 11th and 12th tin baths respectively. The graphite baffle groups are set at the tin liquid edges not covered by glass, which can effectively reduce the backflow of low-temperature tin liquid at the narrow edges to the width. The baffle length is 600-1400mm. Based on the actual situation that the temperature on both sides of the tin bath is slightly lower than that in the middle, and the negative impact of the lateral temperature difference of the tin liquid on the glass, at the same time, the lateral temperature difference will also cause unnecessary flow of the tin liquid, therefore, notches are set on the outer sides of the two first baffles of the graphite baffle group, and these three first baffles are tilted toward the front of the tin bath, which has the effect of guiding the reflux tin liquid outward. As we all know, the glass sheet is not fully covered in the wide section. Therefore, there is an empty area between the side wall of the tin bath in the wide section and the end of the glass plate. The impact of the tin liquid flow here on the glass is smaller than the impact of the tin liquid flow under the glass. The tin liquid is guided outward laterally at these positions, and the reflux tin liquid is partially flowed to the side wall of the tin bath through the notch, which can reduce the lateral temperature difference of the tin bath.

[0015] A graphite baffle group is also provided in the 22-bei area at the end of the tin bath. The inner end of the corresponding first baffle is facing the front of the tin bath and is located in the expanded part. When the tin liquid is pulled by the glass to flow to the 22-bei area, the existence of the expanded part can reduce the flow pressure and reduce the direct impact of the liquid flow on the pool wall at the end of the tin bath, so that the tin liquid at this location partially passes through the gap and partially passes through the area between the two first baffles, and the two liquid flows offset each other behind the first baffles, which can weaken the "torrent" at this location and slow down the reflux of the tin liquid from the source. In addition, the 22-bei area is the "head-up" area of the glass plate. The glass plate here is not in contact with the tin liquid. Therefore, this area as the "offsetting" area of the tin liquid flow has little effect on the glass.

[0016] Due to the heat dissipation effect on both sides of the tin bath, the temperature in the middle of the tin bath is usually higher than the sides. The straight-through water bag used in the narrow section cools the sides and middle of the tin bath without differential cooling, which increases the lateral temperature difference. To address the problem of spatial cooling in the narrow section, the water bag mainly cools the upper surface of the glass, causing a widening temperature difference between the upper and lower surfaces of the glass. The present invention provides multiple cooling water bags in the narrow section, which can make the cooling intensity of the tin liquid in the middle greater than the cooling intensity of the tin bath side walls, and provide stepped cooling to balance the lateral temperature difference in the narrow section.

[0017] To sum up, based on the causes of "shadows" on glass, this solution comprehensively controls and controls in terms of slowing down reflux and reducing temperature differences, weakening the causes to optimize the glass and prepare shadowless glass. The "shadows" and "shadowless" here are relative concepts, which does not mean to completely eliminate the tin flow lines on the glass physically, but to eliminate or weaken the tin flow lines visually. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural diagram of the tin bath of the float glass.

[0019] Figure 2It is a structural diagram of the flow-blocking components and cooling components arranged along the tin bath.

[0020] Figure 3 It is a structural diagram of the first baffle.

[0021] Figure 4 It is a structural diagram of the second baffle.

[0022] Figure 5 yes Figure 1 A magnified view of the local M in the figure.

[0023] In the figure, A, wide section; B, narrow section; C, graphite baffle group; D, graphite baffle; E, first baffle; F, second baffle; G, notch; H, expansion part; I, cooling water bag. DETAILED DESCRIPTION

[0024] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solutions of the present invention, but the present invention is not limited to these embodiments.

[0025] like Figures 1 to 5 As shown, the tin bath for producing ultra-white special float glass without image distortion includes a wide section A and a narrow section B. The tin bath is divided into 22 sections along the glass drawing direction, of which sections 1 to 13 are located in the wide section A, sections 15 to 22 are located in the narrow section B, and section 14 is the transition area between the wide section A and the narrow section B. A graphite barrier group C is provided in the 9-bar area, the 11-bar area, the 12-bar area, and the 22-bar area, respectively, and a graphite barrier D is provided in the 11-bar area, the 13-bar area, and the 15-bar area, respectively. The graphite barrier group C includes two first barriers E extending from the side walls of the tin bath toward the center of the tin bath. The graphite barrier D includes a second barrier F transversely arranged between the two side walls of the tin bath. The first barrier E and the second barrier F are both located at the bottom of the tin bath and below the liquid level of the tin bath. The lower surface of the end of the first barrier E near the side wall of the tin bath has a notch G, and the side of the second barrier F near the glass drawing direction of the tin bath is a corrugated surface.

[0026] The inner ends of the first baffles E in the 9-beta area, the 11-beta area, and the 12-beta area face the glass pulling direction, and the outer ends of the first baffles E in the 22-beta area face the glass pulling direction.

[0027] There is an expansion portion H at the area 22 , and the width of the tin bath gradually increases from the expansion portion H to the end of the tin bath. The first stopper E of the area 22 is located at the expansion portion H.

[0028] The distance between the graphite retaining wall D in the 11-bei area and the tin liquid surface is smaller than that between the graphite retaining wall D in the 13-bei area and the tin liquid surface, and the distance between the graphite retaining wall D in the 13-bei area and the tin liquid surface is smaller than that between the graphite retaining wall D in the 15-bei area and the tin liquid surface.

[0029] The narrow section B is provided with several cooling water bags I, which include two cooling water pipes symmetrically distributed on the tin bath. The water inlet and outlet ends of the cooling water pipes extend beyond the side wall of the tin bath. The cooling water pipe has a serpentine cooling section above the glass plate. The inner end of the cooling section is located at the center line of the tin bath. The distance between each cooling section on the same side of the tin bath and the side wall of the tin bath gradually increases from the beginning to the end of the narrow section B.

[0030] Three graphite barriers D are installed at the tin baths 11, 13, and 15, respectively. These barriers are elevated above the bottom of the bath, 15 to 25 mm above the molten tin surface. This effectively reduces the backflow of low-temperature molten tin from the narrow end to the wide end. Furthermore, because these three barriers are stepped, the lower they are as they approach the end of the bath, gradually blocking the reflowing tin, slowing both its speed and intensity. Furthermore, the second barrier F, with its corrugated surface, is a graphite barrier that diverts the molten tin originally flowing in the direction of glass traction into a transverse flow, slowing its backflow.

[0031] Graphite baffle groups C are set at the 9th, 11th and 12th corners of the tin bath respectively. The graphite baffle groups C are set at the edge of the tin liquid without glass coverage, which can effectively reduce the low-temperature tin liquid at the edge of the narrow section B from flowing back to the width. The baffle length is 600-1400mm. Based on the actual situation that the temperature on both sides of the tin bath is slightly lower than the temperature in the middle, and the negative impact of the horizontal temperature difference of the tin liquid on the glass, at the same time, the horizontal temperature difference will also cause unnecessary flow of the tin liquid, therefore, the two first baffles E of the graphite baffle group C are provided with gaps on the outside. The opening G, and the three first baffles E are tilted toward the front of the tin bath, which has the effect of guiding the refluxed tin liquid outward. As we all know, the glass sheet is not fully covered in the wide section A. Therefore, there is an empty area between the side wall of the tin bath in the wide section A and the end of the glass sheet. The impact of the tin liquid flow here on the glass is smaller than the impact of the tin liquid flow under the glass. The tin liquid is laterally guided outward at these positions, and part of the refluxed tin liquid flows to the side wall of the tin bath through the gap G, which can reduce the lateral temperature difference of the tin bath.

[0032] A graphite baffle group C is also provided in the 22-bei area at the end of the tin bath. The inner end of the corresponding first baffle E faces the front of the tin bath and is located at the expansion part H. When the tin liquid is pulled by the glass to flow to the 22-bei area, the existence of the expansion part H can reduce the flow pressure and slow down the liquid flow from directly impacting the pool wall at the end of the tin bath, so that the tin liquid at this location partially passes through the gap G and partially passes through the area between the two first baffles E, and the two liquid flows offset each other behind the first baffle E, which can weaken the "torrent" at this location and slow down the reflux of the tin liquid from the source. In addition, the 22-bei area is the "head-up" area of the glass plate. The glass plate here is not in contact with the tin liquid. Therefore, this area as an "offsetting" area for the flow of tin liquid has little impact on the glass.

[0033] Due to the heat dissipation from both sides of the tin bath, the temperature in the middle of the tin bath is typically higher than at the sides. The straight-through water drum used in narrow section B provides no differential cooling between the sides and the middle of the tin bath, which increases the lateral temperature difference. To address the spatial cooling problem in narrow section B, the water drum primarily cools the top surface of the glass, widening the temperature difference between the top and bottom surfaces. The present invention incorporates multiple cooling water drums I in narrow section B, ensuring greater cooling intensity in the middle of the tin bath than in the sidewalls. This provides stepped cooling, balancing the lateral temperature difference in narrow section B.

[0034] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope of the appended claims.

Claims

1. A tin bath for producing ultra-clear special float glass without image distortion, the tin bath comprising a wide section (A) and a narrow section (B). The tin bath is divided into 22 sections along the glass drawing direction, wherein sections 1 to 13 are located in the wide section (A), sections 15 to 22 are located in the narrow section (B), and section 14 is a transition area between the wide section (A) and the narrow section (B). The invention is characterized in that: A graphite barrier group (C) is respectively provided in the 9-beta area, the 11-beta area, the 12-beta area and the 22-beta area, and a graphite barrier (D) is respectively provided in the 11-beta area, the 13-beta area and the 15-beta area. The graphite barrier group (C) includes two first barriers (E) extending from the side wall of the tin bath to the center of the tin bath, and the graphite barrier (D) includes a second barrier (F) arranged transversely between the two side walls of the tin bath. The first barrier (E) and the second barrier (F) are both located at the bottom of the tin bath and below the liquid level of the tin bath. The lower surface of the first barrier (E) near the end of the tin bath side wall has a notch (G), and the side of the second barrier (F) near the glass pulling direction of the tin bath is a corrugated surface.

2. The tin bath for producing ultra-clear special float glass without image distortion according to claim 1, characterized in that: The inner ends of the first baffles (E) in the 9-Bei area, the 11-Bei area, and the 12-Bei area face the glass pulling direction, and the outer ends of the first baffles (E) in the 22-Bei area face the glass pulling direction.

3. The tin bath for producing ultra-clear special float glass without image distortion according to claim 2, characterized in that: There is an expansion portion (H) at the area 22, and the width of the tin bath gradually increases from the expansion portion (H) to the end of the tin bath. The first stopper (E) of the area 22 is located at the expansion portion (H).

4. The tin bath for producing ultra-clear special float glass without image distortion according to claim 2, characterized in that: The distance between the graphite barrier (D) in the 11-bei area and the tin liquid surface is smaller than that between the graphite barrier (D) in the 13-bei area and the tin liquid surface, and the distance between the graphite barrier (D) in the 13-bei area and the tin liquid surface is smaller than that between the graphite barrier (D) in the 15-bei area and the tin liquid surface.

5. A tin bath for producing ultra-clear special float glass without image distortion according to claim 1, 2, 3 or 4, characterized in that: The narrow section (B) is provided with a plurality of cooling water bags (I), the cooling water bags (I) comprising two cooling water pipes symmetrically distributed on the tin bath, the water inlet and outlet ends of the cooling water pipes both extending beyond the side wall of the tin bath, the cooling water pipe having a serpentine cooling section above the glass plate, the inner end of the cooling section being located at the center line of the tin bath, and the spacing between each cooling section on the same side of the tin bath and the side wall of the tin bath gradually increasing from the beginning to the end of the narrow section (B).

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