Crystallization roller kiln for improving crystallization warping of microcrystalline glass

Abstract

The utility model provides a crystallization roller way kiln for improving crystallization warping of microcrystalline glass. The crystallization roller way kiln comprises a furnace body with a hearth, an inlet is formed in one side of the furnace body, and an outlet is formed in the other side of the furnace body; a conveying device for conveying from the inlet to the outlet is arranged in the hearth; a temperature control system and a temperature control device matched with the temperature control system are arranged in the hearth; from the inlet to the outlet, the temperature control system comprises a heating unit and a cooling unit which are connected in sequence; the temperature control device comprises a top temperature control device and a bottom temperature control device which operate independently; and the conveying device is arranged between the top temperature control device and the bottom temperature control device. According to the crystallization process of the microcrystalline glass, the crystallization roller kiln disclosed by the utility model not only solves the problem that the microcrystalline glass is warped in the crystallization process, but also can correct and repair the warped microcrystalline glass by independently regulating and controlling the temperatures of the tops and the bottoms of the heating unit and the cooling unit.

Description

Technical Field

[0001] The utility model belongs to the technical field of crystallization heating of microcrystalline glass, and particularly relates to a crystallization roller hearth furnace for improving the crystallization warping of microcrystalline glass. Background Art

[0002] Microcrystalline electronic glass has been increasingly widely used in mobile phone cover glass in recent years due to its high impact resistance and high scratch resistance.

[0003] At present, the forming methods of microcrystalline glass include: melting brick casting and calendering forming. The process route of the melting brick casting includes melting, melting brick casting forming, annealing treatment, crystallization treatment, and machining treatment in sequence; the process route of the calendering forming includes melting, calendering forming, annealing treatment, crystallization treatment, and machining treatment in sequence. After crystallization, the microcrystalline glass products (glass bricks and glass sheets) obtained by the above two forming methods will have the defect of warping, especially the calendered glass sheets are more serious. The warping degree will directly affect the yield of subsequent deep processing.

[0004] At present, the method for improving the warping of microcrystalline glass is to borrow the external force (gravity) of high-temperature resistant materials (such as silicon carbide or aluminum nitride plates, etc.) to reduce the warping degree when the glass sheet is crystallized. For example, high-temperature resistant materials are placed on the upper surface of the glass sheet during crystallization, or high-temperature resistant materials are placed between the stacked glass sheets. In the above improvement method, the procurement price of the high-temperature resistant materials is not low, and they are severely oxidized in the high-temperature environment of the crystallization furnace and have a short service life. Therefore, the cost of the above improvement method is relatively high. In addition, as time goes by, the degree of oxidation of the crystallization furnace gradually increases, the weight of the high-temperature resistant materials becomes lighter and lighter, and the warping degree will increase as the auxiliary gravity decreases. Therefore, the above method cannot solve the warping problem of microcrystalline glass.

[0005] CN 204281557U discloses a glass annealing and crystallization integrated furnace, which includes a shell and a furnace body. One side of the furnace body is provided with an inlet, and the other side is provided with an outlet. The top of the furnace body is equipped with a furnace cover. The glass annealing and crystallization integrated furnace further includes a conveying mechanism for conveying the glass sheet from the inlet to the outlet. There are 7 temperature control zones and corresponding temperature control devices in the furnace body. The temperature control device includes heating elements. The seven temperature control zones are an annealing zone, a slow heating zone, a fast heating zone, a nucleation zone, a crystallization zone, a slow cooling zone, and a fast cooling zone. This device can reduce energy consumption and solve the drawback of glass slag falling and breaking the heating porcelain tube, but it cannot solve the problem of the warping of the corners of microcrystalline glass.

[0006] In summary, it is necessary to provide a solution that can effectively solve the problem of the warping of the corners of microcrystalline glass. Summary of the Utility Model

[0007] Aiming at the deficiencies of the existing technology, the purpose of the present utility model is to provide a crystallization roller hearth furnace for improving the crystallization warping of glass-ceramics. According to the crystallization process of glass-ceramics, the crystallization roller hearth furnace of the present utility model not only solves the problem of warping during the crystallization process of glass-ceramics by separately controlling the temperatures at the top and bottom of the heating unit and the cooling unit, but also can correct and repair the warped glass-ceramics.

[0008] To achieve this purpose, the present utility model adopts the following technical solutions:

[0009] The present utility model provides a crystallization roller hearth furnace for improving the crystallization warping of glass-ceramics, and the crystallization roller hearth furnace includes a furnace body having a furnace chamber;

[0010] One side of the furnace body is provided with an inlet, and the other side is provided with an outlet;

[0011] A conveying device for conveying from the inlet to the outlet is arranged inside the furnace chamber; a temperature control system and a temperature control device matching therewith are arranged inside the furnace chamber;

[0012] In the direction from the inlet to the outlet, the temperature control system includes a heating unit and a cooling unit connected in sequence;

[0013] The temperature control device includes a top temperature control device and a bottom temperature control device that operate independently; the conveying device is arranged between the top temperature control device and the bottom temperature control device.

[0014] In the present utility model, the temperature inside the crystallization roller hearth furnace is controlled by the temperature control system and the temperature control device. Further, the heat transfer and annealing cooling speed on the upper and lower surfaces of the glass-ceramics are made consistent through the independently operating top temperature control device and bottom temperature control device, thereby improving the warping phenomenon caused by uneven heating or cooling of the glass-ceramics;

[0015] In addition, the crystallization roller hearth furnace provided by the present utility model not only saves the procurement cost of high-temperature resistant materials, but also solves the instability of the increased warping degree caused by the oxidation of high-temperature resistant materials.

[0016] It should be noted that the masonry of the crystallization roller hearth furnace of the present utility model is entirely made of high-grade refractory heat-insulating materials; different refractory heat-insulating materials are selected according to different temperature requirements in the crystallization roller hearth furnace, with a long service life, good effect, and a relatively low temperature on the outer surface of the furnace to achieve the effect of energy conservation and consumption reduction.

[0017] As a preferred technical solution of the present utility model, in the direction from the inlet to the outlet, the heating unit includes a preheating zone, a rapid heating zone, a nucleation zone, a first heating zone, a constant temperature zone, a second heating zone, and a crystallization heat preservation zone connected in sequence.

[0018] From the inlet to the outlet direction, the temperature reduction unit includes an annealing zone, a cooling zone, and a rapid cooling zone connected in sequence.

[0019] As a preferred technical solution of the present utility model, the length of the crystallization roller hearth furnace is 50 - 55 m. For example, it can be 50 m, 51 m, 52 m, 53 m, 54 m, or 55 m, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.

[0020] As a preferred technical solution of the present utility model, the conveying device includes a driving motor, a reduction gearbox helical gear, and a carrying roller.

[0021] Preferably, the driving motor provides power for the conveying device.

[0022] More specifically, in the present utility model, the angle of the reduction gearbox helical gear in the conveying device is 45°.

[0023] As a preferred technical solution of the present utility model, the top temperature control device and the bottom temperature control device of the heating-up unit each independently include a heating pipe and a temperature control system;

[0024] Preferably, the temperature control system controls the heating power of the heating pipe by monitoring the temperature of the heating pipe.

[0025] It should be noted that in the present utility model, the heating device includes an upper heating device and a lower heating device; a carrying roller is provided between the upper heating device and the upper heating device;

[0026] The heating pipe is an electric heating element; the electric heating element is a straight radiant resistance wire. More specifically, the resistance wire of the upper heating device adopts a ceramic rod installation type, the resistance wire is arranged along the furnace width direction, not grouped in the width direction, each ceramic roller and the resistance wire form an I shape to form a whole, and the resistance wire lead-out wire is connected to one side of the furnace body; the resistance wire of the lower heating device is arranged along the furnace width direction, not grouped in the width direction, holes for inserting the electric heating element are reserved on both side walls, each ceramic roller and the resistance wire form an I shape to form a whole, and it can be drawn out from one side of the furnace body, which is convenient for wiring installation and convenient for handling faults in the hot state.

[0027] As a preferred technical solution of the present utility model, the length of the preheating zone is 0.8 - 1.2 m. For example, it can be 3.5 m, 3.6 m, 3.7 m, 3.8 m, 3.9 m, 4.0 m, 4.1 m, 4.2 m, 4.3 m, 4.4 m, or 4.5 m, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.

[0028] Preferably, the length of the rapid heating zone is 3.5 - 4.5 m. For example, it can be 3.5 m, 3.7 m, 3.9 m, 4.1 m, 4.3 m, or 4.5 m, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable.

[0029] Preferably, the length of the nucleation zone is 9 - 12 m. For example, it can be 9 m, 9.5 m, 10 m, 10.5 m, 11 m, 11.5 m, or 12 m, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable.

[0030] Preferably, the length of the first heating zone is 1.5 - 2.5 m. For example, it can be 1.5 m, 1.7 m, 1.9 m, 2.1 m, 2.3 m, or 2.5 m, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable.

[0031] Preferably, the length of the constant temperature zone is 11 - 13 m. For example, it can be 11 m, 11.4 m, 11.8 m, 12.2 m, 12.6 m, or 13 m, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable.

[0032] Preferably, the length of the second heating zone is 1.5 - 2.5 m. For example, it can be 1.5 m, 1.7 m, 1.9 m, 2.1 m, 2.3 m, or 2.5 m, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable.

[0033] Preferably, the length of the crystallization heat preservation zone is 5.5 - 6.5 m. For example, it can be 5.5 m, 5.7 m, 5.9 m, 6.1 m, 6.3 m, or 6.5 m, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable.

[0034] In the present utility model, from the inlet to the outlet direction, the temperature of each region in the heating unit gradually increases. The temperature of the preheating zone is 50 - 300 °C. For example, it can be 50 °C, 100 °C, 150 °C, 200 °C, 250 °C, or 300 °C, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable;

[0035] Preferably, the temperature of the rapid heating zone is 120 - 580 °C. For example, it can be 120 °C, 160 °C, 200 °C, 300 °C, 400 °C, 500 °C, or 580 °C, but is not limited to the listed values. Other values within the numerical range that are not listed are equally applicable;

[0036] Preferably, the temperature of the nucleation zone is 520 - 580°C. For example, it can be 520°C, 530°C, 540°C, 550°C, 560°C, 570°C or 580°C, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable;

[0037] Preferably, the temperature of the first heating zone is 520 - 680°C. For example, it can be 520°C, 560°C, 600°C, 640°C or 680°C, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable;

[0038] Preferably, the temperature of the constant temperature zone is 620 - 680°C. For example, it can be 620°C, 630°C, 640°C, 650°C, 660°C, 670°C or 680°C, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable;

[0039] Preferably, the temperature of the second heating zone is 620 - 740°C. For example, it can be 620°C, 640°C, 680°C, 720°C or 740°C, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable;

[0040] Preferably, the temperature of the crystallization heat preservation zone is 680 - 740°C. For example, it can be 680°C, 690°C, 700°C, 710°C, 720°C, 730°C or 740°C, but is not limited to the listed values. Other unlisted values within the numerical range are equally applicable.

[0041] As a preferred technical solution of the present utility model, the top temperature control device and the bottom temperature control device of the cooling unit independently include a fan cooling device and a temperature control system respectively.

[0042] Preferably, the temperature control system controls the cooling air flow of the fan cooling device by monitoring the temperature of the fan cooling device.

[0043] As a preferred technical solution of the present utility model, the fan cooling device includes a fan, an air duct and a heat exchange pipe connected in sequence.

[0044] As a preferred technical solution of the present utility model, an exhaust pipe is provided at one end of the fan away from the air duct.

[0045] Preferably, the heat exchange pipe includes a first heat exchange pipe and a second heat exchange pipe arranged in parallel.

[0046] Preferably, the first outlet of the air duct is connected to the first heat exchange pipe; the second outlet of the air duct is connected to the second heat exchange pipe.

[0047] In the present utility model, the cooling unit adopts the method of indirect cooling wall + circulating cooling for cooling. Further, a first heat exchange pipeline and a second heat exchange pipeline are independently arranged above and below the idler respectively, and indirect cooling is realized through the heat exchange pipeline.

[0048] In the present utility model, one end of the fan is connected to the air duct to provide cooling air for the heat exchange pipeline; the outlet is connected to the exhaust pipeline, and a cold air suction port is arranged on the inlet pipeline to reduce the temperature of the fan inlet. The fan adopts frequency conversion control and separate temperature control, and the fan frequency conversion participates in the temperature regulation of each zone in the cooling unit.

[0049] As a preferred technical solution of the present utility model, the length of the annealing zone is 5.5 - 6.5 m, for example, it can be 5.5 m, 5.7 m, 5.9 m, 6.1 m, 6.3 m or 6.5 m, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0050] Preferably, the length of the cooling zone is 5.5 - 6.5 m, for example, it can be 5.5 m, 5.7 m, 5.9 m, 6.1 m, 6.3 m or 6.5 m, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0051] Preferably, the length of the rapid cooling zone is 2.5 - 3.5 m, for example, it can be 2.5 m, 2.7 m, 2.9 m, 3.1 m, 3.3 m or 3.5 m, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0052] In the present utility model, from the inlet to the outlet direction, the temperature of each zone in the cooling unit gradually decreases. The temperature of the annealing zone is 740 - 420 °C, for example, it can be 740 °C, 700 °C, 600 °C, 500 °C or 420 °C, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable;

[0053] Preferably, the temperature of the cooling zone is 500 - 220 °C, for example, it can be 500 °C, 450 °C, 400 °C, 350 °C, 300 °C, 250 °C or 220 °C, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable;

[0054] Preferably, the temperature of the rapid cooling zone is 240 - 60 °C, for example, it can be 240 °C, 200 °C, 160 °C, 120 °C, 80 °C or 60 °C, but not limited to the listed values, and other unlisted values within the numerical range are equally applicable.

[0055] The system refers to an equipment system, a device system or a production device.

[0056] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0057] (1) By using the crystallization roller hearth furnace provided by the present utility model, without changing the crystallization regime, the temperature difference between the top and bottom of the roller hearth furnace can be set through the independently operating top temperature control device and bottom temperature control device, so as to achieve the same heat transfer and annealing cooling speed on the upper and lower surfaces of the glass sheet, thereby improving the warping phenomenon caused by uneven heating and cooling;

[0058] (2) The crystallization roller hearth furnace provided by the present utility model has a simple structure, and the problem of crystallization warping of the microcrystalline glass is improved by the partition setting of the furnace. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is a schematic structural diagram of the crystallization roller hearth furnace provided for the specific embodiment of the present utility model;

[0060] Figure 2 is a schematic internal structure diagram of the crystallization roller hearth furnace provided for the specific embodiment of the present utility model;

[0061] Figure 3 is a schematic structural diagram of the fan cooling device provided for the specific embodiment of the present utility model;

[0062] Figure 4 is a schematic diagram of the microcrystalline glass in the shape of a ship warp provided by the utility model;

[0063] Figure 5 is a schematic diagram of the microcrystalline glass in the shape of a turtle warp provided by the present utility model;

[0064] Figure 6 is a schematic diagram of the non-warped microcrystalline glass provided by the present utility model;

[0065] Among them: 1 is a roller, 2 is a preheating zone, 3 is a rapid heating zone, 4 is a nucleation zone, 5 is a first heating zone, 6 is a constant temperature zone, 7 is a second heating zone, 8 is a crystallization insulation zone, 9 is an annealing zone, 10 is a cooling zone, 11 is a rapid cooling zone, 13 is a heating tube, 14 is a heat exchange pipeline, 15 is a microcrystalline glass; 16 is a fan, 17 is an air duct, 18 is a first heat exchange pipeline, 19 is a second heat exchange pipeline. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0066] It should be understood that in the description of the present utility model, the orientation or positional relationship indicated by terms such as "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present utility model.

[0067] It should be noted that in the description of the present utility model, unless otherwise clearly specified and limited, the terms "set", "connected", "coupled" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood through specific circumstances.

[0068] The technical solution of the present utility model will be further described below in conjunction with the drawings and through specific embodiments.

[0069] In a specific embodiment, the present utility model provides a crystallization roller hearth furnace for improving the crystallization warping of glass-ceramics as Figure 1 shown. The crystallization roller hearth furnace includes a furnace body having a furnace chamber;

[0070] An inlet is provided on one side of the furnace body, and an outlet is provided on the other side;

[0071] A conveying device for conveying from the inlet to the outlet is provided inside the furnace chamber; a temperature control system and a temperature control device matching therewith are provided inside the furnace chamber;

[0072] In the direction from the inlet to the outlet, the temperature control system includes a heating-up unit and a cooling-down unit connected in sequence;

[0073] The temperature control device includes a top temperature control device and a bottom temperature control device operating independently; the conveying device is arranged between the top temperature control device and the bottom temperature control device;

[0074] In the direction from the inlet to the outlet, the heating-up unit includes a preheating zone 2, a rapid heating-up zone 3, a nucleation zone 4, a first heating-up zone 5, a constant temperature zone 6, a second heating-up zone 7, and a crystallization heat preservation zone 8 connected in sequence;

[0075] In the direction from the inlet to the outlet, the cooling-down unit includes an annealing zone 9, a cooling zone 10, and a rapid cooling zone 11 connected in sequence;

[0076] The length of the crystallization roller hearth furnace is 50 - 55 m; the internal structure of the crystallization roller hearth furnace is as Figure 2 shown;

[0077] The conveying device includes a driving motor, a reduction box helical gear, and a roller 1; the driving motor provides power for the conveying device;

[0078] The top temperature control device and the bottom temperature control device of the heating unit each independently include a heating pipe 13 and a temperature control system; the temperature control system controls the heating power of the heating pipe 13 by monitoring the temperature of the heating pipe 13;

[0079] The length of the preheating zone 2 is 0.8 - 1.2 m, the length of the rapid heating zone 3 is 3.5 - 4.5 m, the length of the nucleation zone 4 is 9 - 12 m, the length of the first heating zone 5 is 1.5 - 2.5 m, the length of the constant temperature zone 6 is 11 - 13 m, the length of the second heating zone 7 is 1.5 - 2.5 m, and the length of the crystallization heat preservation zone 8 is 5.5 - 6.5 m;

[0080] The top temperature control device and the bottom temperature control device of the cooling unit each independently include a Figure 3 fan cooling device and a temperature control system as shown; the temperature control system controls the cooling air flow of the fan cooling device by monitoring the temperature of the fan cooling device;

[0081] The fan cooling device includes a fan 16, an air duct 17, and a heat exchange pipe connected in sequence; an exhaust pipe is provided at one end of the fan 16 away from the air duct 17; the heat exchange pipe includes a first heat exchange pipe 18 and a second heat exchange pipe 19 arranged in parallel; the first outlet of the air duct 17 is connected to the first heat exchange pipe 18; the second outlet of the air duct 17 is connected to the second heat exchange pipe 19;

[0082] The length of the annealing zone 9 is 5.5 - 6.5 m, the length of the cooling zone 10 is 5.5 - 6.5 m, and the length of the rapid cooling zone 11 is 2.5 - 3.5 m.

[0083] Example 1

[0084] This example provides a crystallization roller hearth furnace for improving the crystallization warping of glass-ceramics as Figure 1 shown, and the crystallization roller hearth furnace includes a furnace body having a furnace chamber;

[0085] An inlet is provided on one side of the furnace body, and an outlet is provided on the other side;

[0086] A conveying device for conveying from the inlet to the outlet is provided inside the furnace chamber; a temperature control system and a temperature control device matching therewith are provided inside the furnace chamber;

[0087] From the inlet to the outlet direction, the temperature control system includes a heating unit and a cooling unit connected in sequence;

[0088] The temperature control device includes a top temperature control device and a bottom temperature control device that operate independently; the conveying device is arranged between the top temperature control device and the bottom temperature control device;

[0089] From the inlet to the outlet direction, the heating unit includes a preheating zone 2, a rapid heating zone 3, a nucleation zone 4, a first heating zone 5, a constant temperature zone 6, a second heating zone 7, and a crystallization insulation zone 8 connected in sequence;

[0090] From the inlet to the outlet direction, the cooling unit includes an annealing zone 9, a cooling zone 10, and a rapid cooling zone 11 connected in sequence;

[0091] The length of the crystallization roller hearth furnace is 52m; the internal structure of the crystallization roller hearth furnace is as Figure 2 shown;

[0092] The conveying device includes a driving motor, a reduction gearbox helical gear, and a roller 1; the driving motor provides power for the conveying device;

[0093] The top temperature control device and the bottom temperature control device of the heating unit each independently include a heating tube 13 and a temperature control system; the temperature control system controls the heating power of the heating tube 13 by monitoring the temperature of the heating tube 13;

[0094] The length of the preheating zone 2 is 1m, the length of the rapid heating zone 3 is 4m, the length of the nucleation zone 4 is 10m, the length of the first heating zone 5 is 2m, the length of the constant temperature zone 6 is 12m, the length of the second heating zone 7 is 2m, and the length of the crystallization insulation zone 8 is 6m;

[0095] The top temperature control device and the bottom temperature control device of the cooling unit each independently include a Figure 3 shown fan cooling device and a temperature control system; the temperature control system controls the cooling air flow of the fan cooling device by monitoring the temperature of the fan cooling device;

[0096] The fan cooling device includes a fan 16, an air duct 17, and a heat exchange pipe connected in sequence; an exhaust pipe is arranged at one end of the fan 16 away from the air duct 17; the heat exchange pipe includes a first heat exchange pipe 18 and a second heat exchange pipe 19 arranged in parallel; a first outlet of the air duct 17 is connected to the first heat exchange pipe 18; a second outlet of the air duct 17 is connected to the second heat exchange pipe 19;

[0097] The length of the annealing zone 9 is 6 m, the length of the cooling zone 10 is 6 m, and the length of the rapid cooling zone 11 is 3 m.

[0098] Comparative Example 1

[0099] This comparative example provides a crystallization roller hearth furnace for improving the crystallization warping of glass-ceramics. The only difference between this crystallization roller hearth furnace and that of Example 1 is that:

[0100] In this comparative example, the independently operating top temperature control device and bottom temperature control device are adjusted to operate as a whole.

[0101] Application Example 1

[0102] This application example provides a method for crystallizing glass using the crystallization roller hearth furnace provided in Example 1.

[0103] During the crystallization process, the glass-ceramics are placed on the conveying device and conveyed from the inlet to the outlet; when the glass shows a boat warping shape as shown in Figure 4 , the bottom temperature of one or more of the annealing zone 9, cooling zone 10, or rapid cooling zone 11 is reduced by the fan cooling device, increasing the temperature difference between the top and bottom of the temperature reduction unit, and obtaining a warping-free glass-ceramics as shown in Figure 6 .

[0104] Application Example 2

[0105] This application example provides a method for crystallizing glass using the crystallization roller hearth furnace provided in Example 1.

[0106] During the crystallization process, the glass-ceramics are placed on the conveying device and conveyed from the inlet to the outlet; when the glass shows a tortoise warping shape as shown in Figure 5 , the top temperature of one or more of the annealing zone 9, cooling zone 10, or rapid cooling zone 11 is increased by the fan cooling device, and the bottom temperature is correspondingly reduced, obtaining a warping-free glass-ceramics as shown in Figure 6 .

[0107] Application Example 3

[0108] This application example provides a method for crystallizing glass using the crystallization roller hearth furnace provided in Example 1.

[0109] During the crystallization process, the glass-ceramics are placed on the conveying device and conveyed from the inlet to the outlet; when the glass shows a shape as shown in Figure 5When in the warped shape shown, by means of the heating device, reduce the top temperature of one or more of the temperature reduction zone 2, rapid heating-up zone 3, nucleation zone 4, first heating-up zone 5, constant temperature zone 6, second heating-up zone 7 and crystallization heat preservation zone 8, and correspondingly reduce the bottom temperature, to obtain the Figure 6 warp-free glass-ceramics shown.

[0110] As can be seen from Application Examples 1 - 3, by using the crystallization roller hearth furnace provided by the present utility model, when warping occurs during the crystallization of the glass, it is possible to correct the warping phenomenon during the crystallization of the glass-ceramics by adjusting in real time the temperature difference between the top and the bottom of each area in the furnace, and obtain glass-ceramics with no warping and good flatness.

[0111] Comparative Application Example 1

[0112] This comparative application example provides a method for crystallizing glass by using the crystallization roller hearth furnace provided by Comparative Example 1.

[0113] During the crystallization treatment process, place the glass-ceramics on the conveying device and convey from the inlet to the outlet; when warping such as Figure 5 shown occurs during the crystallization of the glass, since the top temperature and the bottom temperature of the roller hearth furnace provided by Comparative Example 1 cannot be operated independently, it is impossible to achieve a temperature difference between the top and the bottom in the furnace, that is, the crystallization roller hearth furnace provided by Comparative Example 1 cannot improve the warping phenomenon during the crystallization of the glass-ceramics.

[0114] To sum up, by using the crystallization roller hearth furnace provided by the present utility model, it is possible to set the temperature difference between the top and the bottom of the roller hearth furnace without changing the crystallization regime, so as to make the heat transfer and the annealing and cooling rates of the upper and lower surfaces of the glass sheet consistent, thereby improving the warping phenomenon caused by uneven heating and cooling.

[0115] The applicant declares that the above description is only the specific implementation manner of the present utility model, but the protection scope of the present utility model is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model fall within the protection scope and the disclosure scope of the present utility model.

Claims

1. A crystallization roller hearth furnace for improving the crystallization warpage of glass-ceramics, characterized in that, The crystallization roller hearth kiln includes a furnace body having a hearth; One side of the furnace body is provided with an inlet, and the other side is provided with an outlet; Inside the hearth, there is a conveying device that conveys from the inlet to the outlet; inside the hearth, there is a temperature control system and a temperature control device matching it; In the direction from the inlet to the outlet, the temperature control system includes a heating unit and a cooling unit connected in sequence; The temperature control device includes a top temperature control device and a bottom temperature control device that operate independently; the conveying device is arranged between the top temperature control device and the bottom temperature control device.

2. The crystallization roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 1, wherein In the direction from the inlet to the outlet, the heating unit includes a preheating zone, a rapid heating zone, a nucleation zone, a first heating zone, a constant temperature zone, a second heating zone, and a crystallization heat preservation zone connected in sequence; In the direction from the inlet to the outlet, the cooling unit includes an annealing zone, a cooling zone, and a rapid cooling zone connected in sequence.

3. The crystallization roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 1, wherein, The length of the crystallization roller hearth kiln is 50 - 55 m.

4. The crystallization roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 1, characterized in that, The conveying device includes a driving motor, a reduction gearbox helical gear, and a carrying roller; The driving motor provides power for the conveying device.

5. The crystallization roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 1, characterized in that, The top temperature control device and the bottom temperature control device of the heating unit each independently include heating tubes and a temperature control system; The temperature control system controls the heating power of the heating tubes by monitoring the temperature of the heating tubes.

6. The crystallization roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 2, wherein, The length of the preheating zone is 0.8 - 1.2 m; The length of the rapid heating zone is 3.5 - 4.5 m; The length of the nucleation zone is 9 - 12 m; The length of the first heating zone is 1.5 - 2.5 m; The length of the constant temperature zone is 11 - 13 m; The length of the second heating zone is 1.5 - 2.5 m; The length of the crystallization heat preservation zone is 5.5 - 6.5 m.

7. The crystallizing roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 1, wherein The top temperature control device and the bottom temperature control device of the cooling unit each independently include a fan cooling device and a temperature control system; The temperature control system controls the cooling air flow rate of the fan cooling device by monitoring the temperature of the fan cooling device.

8. The crystallizing roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 7, wherein, The fan cooling device includes a fan, an air duct, and a heat exchange pipe connected in sequence; 9. The crystallization roller hearth furnace for improving the crystallization warpage of glass-ceramics according to claim 8, characterized in that, One end of the fan away from the air duct is provided with an exhaust pipe; The heat exchange pipe includes a first heat exchange pipe and a second heat exchange pipe arranged in parallel; The first outlet of the air duct is connected to the first heat exchange pipe; the second outlet of the air duct is connected to the second heat exchange pipe.

10. The crystallization roller hearth furnace for improving the crystallization warping of glass-ceramics according to claim 2, wherein, The length of the annealing zone is 5.5 - 6.5 m; The length of the cooling zone is 5.5 - 6.5 m; The length of the rapid cooling zone is 2.5 - 3.5 m.

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