Freeze-thaw control method for glass melting furnace

Abstract

A freeze-thaw control method for discharging of a glass melting furnace is disclosed. In the method, a first power supply and a second power supply are turned on, and power is supplied to a first induction coil and a second induction coil respectively to heat a discharging pipe. The first power supply and the second power supply are adjusted so that the upper temperature of the discharging pipe is lower than the lower temperature. When the lower temperature of the discharging pipe reaches the discharging temperature, the heating power of the first induction coil is controlled to maintain the lower temperature of the discharging pipe while the second induction coil continues to heat the upper part of the discharging pipe to maintain the discharging temperature, and the glass liquid in the furnace begins to flow out, and the second power supply is turned off, and the discharging flow rate is reduced until it stops, and the first power supply is turned off, and the second power supply is turned on, and the second induction coil heats the discharging pipe, and the upper temperature of the discharging pipe is monitored, and the power of the second power supply is adjusted so that the upper temperature of the discharging pipe is at least 300°C lower than the glass liquidus temperature, so as to reduce the crystallization of the glass liquid inside the discharging pipe. The freeze-thaw control method for a glass melting furnace significantly improves the operational safety of discharging and the temperature of the entire discharging pipe is controllable.

Description

Technical Field

[0001] The invention relates to the technical field of glass melting, and in particular to a freeze-thaw control method for discharge of a glass melting furnace. Background Art

[0002] The molten glass obtained by melting in a glass melting furnace needs to be discharged from the furnace in some way. One of the ways is the freeze-thaw method of bottom discharging, that is, installing a discharging device at the bottom of the furnace. When discharging is not needed, the discharging port is set to a lower temperature, and the internal molten glass is "frozen"; when discharging is needed, the discharging port is heated to melt the internal glass, and the molten glass in the furnace can be discharged. This method has the function of a discharging valve, so it is also called freeze-thaw valve discharging. The freeze-thaw valve has the advantages of simple operation and the molten glass is not easy to overflow.

[0003] The German VEK glass solidification furnace uses a freeze-thaw valve-type bottom discharge device. The discharge pipe is installed at the bottom of the furnace, and its upper part is pre-buried inside the refractory material of the furnace. The lower tubular structure is exposed outside the furnace, and a medium-frequency induction coil is used to heat the discharge pipe. The existing technology uses high-temperature resistant and corrosion-resistant metal materials as the discharge pipe, and uses a medium-frequency induction coil to heat the discharge pipe. The top of the discharge pipe is pre-buried inside the furnace bottom. In order to prevent the furnace shell temperature from being too high, there is insulation material between the top disc of the discharge pipe and the furnace bottom support. The part of the discharge pipe surrounded by the insulation material of the furnace bottom cannot be directly heated by the induction coil, so the temperature of the glass liquid there cannot be controlled, that is, there is a risk of too low or too high temperature. This situation brings two consequences: first, when the freeze-thaw valve is turned to the open state, that is, when the furnace is ready to discharge, the temperature of the glass inside the buffer section at the bottom of the furnace is relatively low and is in a solid state, and the induction coil can only directly heat the external discharge pipe, and can only rely on heat conduction to heat the glass inside the buffer section at the bottom of the furnace. Therefore, it is difficult to determine the time when the glass liquid starts to flow out. In more serious cases, if crystallization occurs in the glass at this location, the solid-liquid transition temperature is higher, which may lead to the problem of being unable to discharge. In another case, when the freeze-thaw valve is turned to the closed state, that is, when the furnace is ready to stop discharging, due to the insulation effect of the insulation material, the temperature of the buffer section at the bottom of the furnace drops slowly. Even if the induction heating is stopped, the glass liquid inside the discharge channel is difficult to solidify, which will create a risk of being unable to stop discharging.

[0004] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a freeze-thaw control method for a glass melting furnace to solve the problem that the temperature of the entire section of the bottom discharge pipe of the existing glass melting furnace, especially the glass solidification melting furnace, is uneven and uncontrollable and is easy to be blocked.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A glass melting furnace freeze-thaw control method of the present invention comprises:

[0008] A glass melting pool is installed on a furnace bottom support, the glass melting pool contains molten glass liquid and is provided with a first channel for leading out the glass liquid at the bottom, the furnace bottom support is provided with a first through hole aligned with the first channel, a discharge pipe is sealedly sleeved on the first channel and the first through hole, the discharge pipe comprises a disc-shaped structure directly supported on the glass melting pool and a tubular structure extending downward from the disc-shaped structure, the tubular structure extends out of the furnace bottom support, the tubular structure extending out of the furnace bottom support is sleeved with a first induction coil for heating the lower part of the discharge pipe, the first induction coil is powered by a first power supply, an insulating medium layer is provided between the tubular structure and the glass melting pool, the insulating medium layer is pre-buried with a second induction coil for heating the upper part of the discharge pipe located in the glass melting furnace, the second induction coil is powered by a second power supply;

[0009] The first power supply and the second power supply are turned on to supply power to the first induction coil and the second induction coil respectively to heat the discharge pipe. The first power supply and the second power supply are adjusted to make the upper temperature of the discharge pipe lower than the lower temperature. When the lower temperature of the discharge pipe reaches the discharge temperature, the heating power of the first induction coil is controlled to maintain the lower temperature of the discharge pipe while the second induction coil continues to heat until the upper part of the discharge pipe reaches the discharge temperature and then maintains it. The glass liquid in the furnace begins to flow out.

[0010] Turn off the second power supply, reduce the discharge flow rate until it stops, when the temperature of the upper part of the discharge pipe drops to 300℃-600℃ below the glass liquidus temperature, increase the heating power of the first induction coil to make the temperature of the lower part of the discharge pipe reach the discharge temperature again, so that the glass in the lower part of the discharge pipe can be discharged cleanly, turn off the first power supply, turn on the second power supply, heat the discharge pipe with the second induction coil, monitor the temperature of the upper part of the discharge pipe, adjust the power of the second power supply to make the temperature of the upper part of the discharge pipe at least 300℃ lower than the glass liquidus temperature, and reduce the crystallization of the glass liquid inside the discharge pipe.

[0011] In the freeze-thaw control method for a glass melting furnace, the second induction coil can be introduced with a cooling medium for cooling.

[0012] In the freeze-thaw control method for a glass melting furnace, the second induction coil is wound by a hollow copper tube.

[0013] In the freeze-thaw control method for a glass melting furnace, after turning on the first power supply and the second power supply to respectively power the first induction coil and the second induction coil to heat the discharge pipe, the inlet temperature of the cooling medium in the second induction coil is controlled between 20°C and 50°C.

[0014] In the freeze-thaw control method of a glass melting furnace, after turning off the second power supply, the inlet temperature of the cooling medium in the second induction coil is controlled to be less than 10°C, and the discharge flow rate is reduced until it stops; when the temperature of the upper part of the discharge pipe drops to 300°C-600°C below the glass liquidus temperature, the heating power of the first induction coil is increased to make the temperature of the lower part of the discharge pipe reach the discharge temperature again, so that the glass in the lower part of the discharge pipe is discharged cleanly, the first power supply is turned off, the inlet temperature of the cooling medium in the second induction coil is controlled to be between 20°C-50°C, the second power supply is turned on to power the second induction coil, and the discharge pipe is started to be heated. The power of the second power supply is set between 0 and 10kW. The second power supply is turned on, the second induction coil heats the discharge pipe, the temperature of the upper part of the discharge pipe is monitored, and the power of the second power supply is adjusted to make the temperature of the upper part of the discharge pipe at least 300°C lower than the glass liquidus temperature, thereby reducing the crystallization of the glass liquid inside the discharge pipe.

[0015] In the freeze-thaw control method for a glass melting furnace, the cooling medium includes compressed air, liquid nitrogen or circulating water.

[0016] In the freeze-thaw control method for a glass melting furnace, the operating frequency of the first power supply is between 500 Hz and 30 kHz, and the operating frequency of the second power supply is between 10 kHz and 5.5 MHz.

[0017] In the freeze-thaw control method for a glass melting furnace, the top of the first channel is a funnel-shaped structure, and the tubular structure located in the glass melting furnace is a conical structure adapted to the funnel-shaped structure.

[0018] In the freeze-thaw control method for a glass melting furnace, the inclination angle of the funnel-shaped structure or the cone-shaped structure is 0-135°.

[0019] In the freeze-thaw control method for a glass melting furnace, the discharge temperature is the liquidus temperature T of the molten glass. L Add 50°C to the liquidus temperature of the molten glass plus 260°C.

[0020] In the above technical scheme, a freeze-thaw control method for a glass melting furnace provided by the present invention has the following beneficial effects: compared with the prior art, the top of the discharge pipe is pre-buried inside the furnace bottom, the disc-shaped structure of the discharge pipe is directly supported on the glass melting pool and the upper part of the discharge pipe is directly heated by the second induction coil, the temperature of the entire discharge pipe is uniform and controllable, avoiding the risk of too low or too high temperature, when the freeze-thaw valve is turned to the open state, that is, when the furnace is ready to discharge, the temperature of the glass inside the buffer section at the bottom of the furnace is relatively low and in a solid state, while the first induction coil can only directly heat the external discharge pipe, that is, the lower part of the discharge pipe, and the upper part of the discharge pipe is directly heated by the second induction coil to accurately control the time when the glass liquid starts to flow out, avoiding crystallization of the glass and the problem of being unable to discharge due to a higher solid-liquid transition temperature; when the freeze-thaw valve is turned to the closed state, that is, when the furnace is ready to stop discharging, due to the slow drop in the temperature of the buffer section at the bottom of the furnace, the cooling medium is introduced through the second induction coil to quickly and accurately solidify the glass liquid inside the discharge channel, avoiding the risk of being unable to stop discharging. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0022] Figure 1 A schematic diagram of the installation arrangement of a glass melting furnace freeze-thaw control method provided by an embodiment of the present invention.

[0023] Figure 2 A schematic diagram of the installation arrangement of a glass melting furnace freeze-thaw control method provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0027] In the description of the present invention, it should be understood that the terms center, longitudinal, lateral, length, width, thickness, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside, clockwise, counterclockwise, etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, which are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] In addition, the terms first and second are used only for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as first and second may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of multiple is two or more, unless otherwise clearly and specifically defined.

[0029] In the present invention, unless otherwise clearly specified and limited, the terms such as installation, connection, connection, fixing, etc. should be understood in a broad sense, for example, it can be fixed connection, detachable connection, or integrated; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In the present invention, unless otherwise clearly specified and limited, a first feature being above or below a second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, a first feature being above, above, and above a second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being below, below, and below a second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0031] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0032] See also Figure 1-2 As shown, in one embodiment, a glass melting furnace freeze-thaw control method of the present invention includes:

[0033] A glass melting pool 6 is installed on a furnace bottom support 5, the glass melting pool 6 contains molten glass liquid 7 and is provided with a first channel for leading out the glass liquid 7 at the bottom, the furnace bottom support 5 is provided with a first through hole aligned with the first channel, a discharge pipe 1 is sealedly sleeved on the first channel and the first through hole, the discharge pipe 1 comprises a disc-shaped structure directly supported on the glass melting pool 6 and a tubular structure extending downward from the disc-shaped structure, the tubular structure extends out of the furnace bottom support 5, the tubular structure extending out of the furnace bottom support 5 is sleeved with a first induction coil 2 for heating the lower part of the discharge pipe 1, the first induction coil 2 is powered by a first power supply, an insulating medium layer 3 is provided between the tubular structure and the glass melting pool 6, the insulating medium layer 3 is pre-buried with a second induction coil 4 for heating the upper part of the discharge pipe 1 located in the glass melting furnace, the second induction coil 4 is powered by a second power supply;

[0034] The first power supply and the second power supply are turned on to supply power to the first induction coil 2 and the second induction coil 4 respectively to heat the discharge pipe 1. The first power supply and the second power supply are adjusted to make the upper temperature of the discharge pipe 1 lower than the lower temperature. When the lower temperature of the discharge pipe 1 reaches the discharge temperature, the heating power of the first induction coil 2 is controlled to maintain the lower temperature of the discharge pipe 1 while the second induction coil 4 continues to heat until the upper part of the discharge pipe 1 reaches the discharge temperature and then maintains it. The glass liquid 7 in the furnace begins to flow out.

[0035] Turn off the second power supply, reduce the discharge flow rate until it stops, when the temperature of the upper part of the discharge pipe 1 drops to 300℃-600℃ below the phase line temperature of the glass liquid 7, increase the heating power of the first induction coil 2, make the temperature of the lower part of the discharge pipe 1 reach the discharge temperature again, discharge the glass in the lower part of the discharge pipe 1 cleanly, turn off the first power supply, turn on the second power supply, heat the discharge pipe 1 with the second induction coil 4, monitor the temperature of the upper part of the discharge pipe 1, adjust the power of the second power supply to make the temperature of the upper part of the discharge pipe 1 at least 300℃ lower than the phase line temperature of the glass liquid 7, reduce the crystallization of the glass liquid 7 inside the discharge pipe 1.

[0036] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, the second induction coil 4 can be introduced with a cooling medium for cooling.

[0037] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, the second induction coil 4 is wound by a hollow copper tube.

[0038] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, after turning on the first power supply and the second power supply to respectively power the first induction coil 2 and the second induction coil 4 to heat the discharge pipe 1, the inlet temperature of the cooling medium in the second induction coil 4 is controlled between 20°C and 50°C.

[0039] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, after turning off the second power supply, the inlet temperature of the cooling medium in the second induction coil 4 is controlled to be less than 10°C, and the discharge flow rate is reduced until it stops; when the temperature of the upper part of the discharge pipe 1 drops to 300°C-600°C below the phase line temperature of the glass liquid 7, the heating power of the first induction coil 2 is increased to make the temperature of the lower part of the discharge pipe 1 reach the discharge temperature again, so that the glass in the lower part of the discharge pipe 1 is discharged cleanly, the first power supply is turned off, the inlet temperature of the cooling medium in the second induction coil 4 is controlled to be between 20°C-50°C, the second power supply is turned on to power the second induction coil 4, and the discharge pipe 1 begins to be heated. The power of the second power supply is set between 0 and 10kW. When the second power supply is turned on, the second induction coil 4 heats the discharge pipe 1, the temperature of the upper part of the discharge pipe 1 is monitored, and the power of the second power supply is adjusted so that the temperature of the upper part of the discharge pipe 1 is at least 300°C lower than the phase line temperature of the glass liquid 7, thereby reducing the crystallization of the glass liquid 7 inside the discharge pipe 1.

[0040] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, the cooling medium includes compressed air, liquid nitrogen or circulating water.

[0041] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, the operating frequency of the first power supply is between 500 Hz and 30 kHz, and the operating frequency of the second power supply is between 10 kHz and 5.5 MHz.

[0042] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, the top of the first channel is a funnel-shaped structure, and the tubular structure located in the glass melting furnace is a conical structure adapted to the funnel-shaped structure.

[0043] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, the inclination angle of the funnel-shaped structure or the cone-shaped structure is 0-135°.

[0044] In a preferred embodiment of the freeze-thaw control method for a glass melting furnace, the discharge temperature is the liquidus temperature T of the molten glass. L Add 50°C to the liquidus temperature of the molten glass plus 260°C.

[0045] In one embodiment, the discharge pipe 1 is a disc-shaped structure at the top and a tubular structure at the bottom, with a discharge passage at the center, and the top of the discharge pipe 1 is installed inside the furnace bottom. The first induction coil 2 is sleeved on the outside of the discharge pipe 1, connected to the first power supply, and the operating frequency is a value between 500 Hz and 30 kHz. The glass melting pool 6 is built of refractory materials, and the inside is molten glass liquid 7. The glass melting pool 6 is installed on the bottom support 5 of the melting furnace. There is a pre-buried second induction coil 4 inside the insulating medium layer 3 between the top of the discharge pipe 1 and the bottom support 5, which surrounds the outside of the discharge pipe 1 and can heat the upper part of the discharge pipe 1. The second induction coil 4 is connected to the second power supply, and the operating frequency of the second power supply is a value between 10 kHz and 5.5 MHz. Temperature measuring points are set on the upper and lower parts of the discharge pipe 1, and a thermocouple, a thermal resistor or an infrared temperature measuring device is used to measure the temperature of the discharge pipe.

[0046] In one embodiment, the second induction coil 4 is wound by a copper tube, and a cooling medium is passed into the copper tube, which can be used to quickly reduce the temperature of the discharge pipe and speed up the closing speed of the freeze-thaw valve.

[0047] In one embodiment, the dimension relationship between the total height h of the discharge pipe 1 and the diameter r of the internal discharge passage is set to h / r>150.

[0048] In one embodiment, the discharge pipe 1 is funnel-shaped, that is, the top of the discharge channel is conical, and the insulating medium layer 3 and the second induction coil 4 therein are adjusted in shape accordingly. The opening angle of the discharge channel at the top of the discharge pipe 1 is set to a value between 0-135°.

[0049] In one embodiment, in the control method,

[0050] Discharging process:

[0051] Turn on the first power supply and the second power supply to supply power to the first induction coil 2 and the second induction coil 4 respectively, and start heating the discharge pipe 1. Control the inlet temperature of the cooling medium in the second induction coil 4 between 20°C and 50°C. The power of the first power supply is set between 4kW and 50kW, and the power of the second induction power supply is set between 3kW and 40kW. Adjust the power of the power supply so that the temperature of the upper part of the discharge pipe 1 is lower than the temperature of the lower part. When the temperature of the lower part of the discharge pipe reaches the discharge temperature, control the heating power of the first induction coil 2 to keep the temperature of the lower part of the discharge pipe stable. At the same time, the second induction coil 4 continues to heat so that the upper part of the discharge pipe reaches the discharge temperature and remains stable, and the glass liquid in the furnace begins to flow out. The discharge temperature is set to T L +50℃-T L +260℃, where T L It is the liquidus temperature of the molten glass.

[0052] Stop the discharging process:

[0053] Turn off the power of the second induction coil 4, control the inlet temperature of the cooling medium in the second induction coil 4 to be less than 10°C, and reduce the heating power of the first induction coil 2 to a value in the range of 3kW-8kW. The discharge flow rate is slowly reduced until it stops. When the temperature of the upper part of the discharge pipe 1 drops to 300°C-600°C below the liquidus temperature of the glass, increase the heating power of the first induction coil 2 so that the temperature of the lower part of the discharge pipe reaches the discharge temperature again, so that the glass in the lower part of the discharge pipe is discharged cleanly.

[0054] Turn off the heating power of the first induction coil 2. Control the inlet temperature of the cooling medium in the second induction coil 4 to be between 20°C and 50°C. Turn on the second power supply to power the second induction coil 4 and start heating the discharge pipe. The power of the second power supply is set between 0 and 10kW. Monitor the temperature of the upper part of the discharge pipe 1 and adjust the power of the second power supply to make the temperature of the upper part of the discharge pipe 1 at least 300°C lower than the liquidus temperature of the glass, so as to reduce the crystallization of the glass liquid inside the discharge pipe to prevent the discharge pipe 1 from being blocked.

[0055] Finally, it should be noted that the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making any creative work are within the scope of protection of the present application.

[0056] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for controlling freeze-thaw in a glass melting furnace, characterized in that: It includes the following steps: A glass melting pool is installed on a furnace bottom support, the glass melting pool contains molten glass liquid and is provided with a first channel for leading out the glass liquid at the bottom, the furnace bottom support is provided with a first through hole aligned with the first channel, a discharge pipe is sealedly sleeved on the first channel and the first through hole, the discharge pipe comprises a disc-shaped structure directly supported on the glass melting pool and a tubular structure extending downward from the disc-shaped structure, the tubular structure extends out of the furnace bottom support, the tubular structure extending out of the furnace bottom support is sleeved with a first induction coil for heating the lower part of the discharge pipe, the first induction coil is powered by a first power supply, an insulating medium layer is provided between the tubular structure and the glass melting pool, the insulating medium layer is pre-buried with a second induction coil for heating the upper part of the discharge pipe located in the glass melting furnace, the second induction coil is powered by a second power supply; The first power supply and the second power supply are turned on to supply power to the first induction coil and the second induction coil respectively to heat the discharge pipe. The first power supply and the second power supply are adjusted to make the upper temperature of the discharge pipe lower than the lower temperature. When the lower temperature of the discharge pipe reaches the discharge temperature, the heating power of the first induction coil is controlled to maintain the lower temperature of the discharge pipe while the second induction coil continues to heat until the upper part of the discharge pipe reaches the discharge temperature and then maintains it. The glass liquid in the furnace begins to flow out. The second induction coil can introduce a cooling medium for cooling. After turning off the second power supply, the inlet temperature of the cooling medium in the second induction coil is controlled to be less than 10°C, and the discharge flow rate is reduced until it stops. When the temperature of the upper part of the discharge pipe drops to 300°C-600°C below the glass liquidus temperature, the heating power of the first induction coil is increased to make the temperature of the lower part of the discharge pipe reach the discharge temperature again, so that the glass in the lower part of the discharge pipe is discharged cleanly, the first power supply is turned off, the inlet temperature of the cooling medium in the second induction coil is controlled to be between 20°C-50°C, the second power supply is turned on to power the second induction coil, and the discharge pipe is started to be heated. The power of the second power supply is set between 0 and 10kW. The second power supply is turned on, the second induction coil heats the discharge pipe, the temperature of the upper part of the discharge pipe is monitored, and the power of the second power supply is adjusted to make the temperature of the upper part of the discharge pipe at least 300°C lower than the glass liquidus temperature, thereby reducing the crystallization of the glass liquid inside the discharge pipe.

2. A glass melting furnace freeze-thaw control method according to claim 1, characterized in that: The second induction coil is wound from a hollow copper tube.

3. A glass melting furnace freeze-thaw control method according to claim 1, characterized in that: After the first power supply and the second power supply are turned on to respectively power the first induction coil and the second induction coil to heat the discharge pipe, the inlet temperature of the cooling medium in the second induction coil is controlled to be between 20°C and 50°C.

4. A glass melting furnace freeze-thaw control method according to claim 1, characterized in that: Cooling media include compressed air, liquid nitrogen or circulating water.

5. A glass melting furnace freeze-thaw control method according to claim 1, characterized in that: The operating frequency of the first power supply is between 500 Hz and 30 kHz, and the operating frequency of the second power supply is between 10 kHz and 5.5 MHz.

6. A glass melting furnace freeze-thaw control method according to claim 1, characterized in that: The top of the first channel is a funnel-shaped structure, and the tubular structure located in the glass melting furnace is a conical structure adapted to the funnel-shaped structure.

7. A glass melting furnace freeze-thaw control method according to claim 1, characterized in that: The inclination angle of the funnel-shaped structure or the cone-shaped structure is 0-135°.

8. A glass melting furnace freeze-thaw control method according to claim 1, characterized in that: The discharge temperature is the liquidus temperature T of the molten glass. L Add 50°C to the liquidus temperature of the molten glass plus 260°C.

Images