Automatic cooling system for microcrystalline glass production, control method of automatic cooling system and roller kiln

Abstract

The invention relates to the technical field of microcrystalline glass production and manufacturing, in particular to an automatic cooling system for microcrystalline glass production, a control method of the automatic cooling system and a roller kiln, and the automatic cooling system is composed of a PLC control module, an upper-layer heat extraction structure, a lower-layer heat extraction structure, an upper-layer air inlet pipe and a lower-layer air inlet pipe. By setting the fan triggering condition, the upper-layer heat extraction fan and / or the lower-layer heat extraction fan can operate at low frequency, the operation cost is low, the actual use energy consumption is low, and the temperature control effect is excellent; by optimizing the distance between every two adjacent sections of temperature zones, the distance between every two adjacent upper-layer air inlet pipes, the distance between every two adjacent lower-layer air inlet pipes and the pipe diameter of the upper-layer air inlet pipes and the pipe diameter of the lower-layer air inlet pipes, the temperature difference between the temperature zones can be effectively reduced, and the purpose of improving the product quality is achieved. And the problem that the product performance is influenced by process fluctuation caused by heat release of the product in the crystallization process can be solved, so that the stability and the consistency of the product during continuous production are guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of glass-ceramic production and manufacturing, and in particular to an automatic cooling system for glass-ceramic production, a control method thereof, and a roller kiln. Background Art

[0002] In the current glass-ceramic manufacturing industry, the glass substrate is nucleated to grow nuclei (preheating stage), followed by high-temperature heat treatment (holding zone) to allow the nuclei to grow, and then annealed to form glass-ceramics (annealing zone). Glass-ceramics require high temperature uniformity, requiring temperature control within ±2°C. However, conventional box-type furnaces or precision annealing furnaces are generally incapable of producing consistent and stable products in continuous batches. To achieve stability and consistency, glass-ceramics are typically manufactured continuously in roller kilns. During the production process, the product undergoes both heat absorption and heat release to achieve the necessary conditions for the physical and chemical reactions. However, this also leads to temperature fluctuations in the kiln. This is primarily due to the fact that the heat absorption process does not significantly affect the kiln temperature. When the temperature falls below the set point, the system automatically increases the temperature to compensate. However, the heat release process lasts longer, causing the actual temperature to exceed the set point, and the kiln temperature to fluctuate significantly, resulting in poor product stability and consistency.

[0003] The roller kilns in the current industry are also equipped with cooling systems, but most of them are installed in the upper layer of the annealing zone, and there is no cooling system in the high-temperature insulation zone (exothermic zone); at the same time, the cooling system mostly installs air ducts above the transmission rollers in the kiln body. After the kiln wall is opened, air is blown directly into the kiln body to achieve a direct cooling effect, but it is easy to cause heat flow turbulence in the kiln, thereby affecting the temperature of other temperature zones or causing the product to explode directly. A few cooling systems also use methods such as water cooling to achieve indirect cooling effects, but there is a risk of corrosion in the laid water pipes, and the temperature inside the kiln body is as high as 1000℃, which leads to the risk of deformation of the water pipes, which is not conducive to actual production and manufacturing.

[0004] To this end, the present invention provides an automatic cooling system for glass-ceramic production, a control method thereof, and a roller kiln. Summary of the Invention

[0005] Based on this, it is necessary to provide an automatic cooling system, its control method and roller kiln for the production of microcrystalline glass to address the above technical problems. The automatic cooling system can cover the high temperature zone and annealing zone, achieve the purpose of temperature control balance, and ensure the stability and consistency of the product.

[0006] According to a first aspect of the present invention, an automatic cooling system for microcrystalline glass production is provided. The automatic cooling system includes: a PLC control module, an upper heat extraction structure electrically connected to the PLC control module and having an exhaust function, a lower heat extraction structure electrically connected to the PLC control module and having an exhaust function, an upper air inlet pipe and a lower air inlet pipe. The kiln body is divided into multiple temperature zones along the length from the high-temperature zone and annealing zone to the kiln outlet, and each temperature zone is provided with an upper heat extraction structure and a lower heat extraction structure. The upper air inlet pipe and the lower air inlet pipe are respectively arranged above and below the furnace cavity, and the air inlet ends of the upper air inlet pipe and the lower air inlet pipe respectively penetrate the kiln body in the vertical direction and extend outward, and are respectively connected to the upper heat extraction structure and the lower heat extraction structure. When the real-time temperature in a certain temperature zone exceeds the preset temperature range of the set temperature, the exhaust of the upper heat extraction structure and / or the lower heat extraction structure is started.

[0007] Optionally, the upper heat extraction structure includes an upper fan frequency converter, an upper heat extraction fan electrically connected to the upper fan frequency converter, and an upper main air duct; the lower heat extraction structure includes a lower fan frequency converter, a lower heat extraction fan electrically connected to the lower fan frequency converter, and a lower main air duct; the air inlet ends of the upper heat extraction fan and the lower heat extraction fan are respectively connected to the upper air inlet duct and the lower air inlet duct embedded in the kiln body through the upper main air duct and the lower main air duct; the upper fan frequency converter and the lower fan frequency converter are respectively electrically connected to the PLC control module to control the frequency conversion of the corresponding upper heat extraction fan and / or the lower heat extraction fan to achieve the purpose of temperature control balance.

[0008] Optionally, each temperature zone is provided with a plurality of temperature sensors electrically connected to the PLC control module, which are used to monitor the upper real-time temperature and / or the lower real-time temperature of each temperature zone in real time, and transmit the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature to the PLC control module.

[0009] Optionally, along the length direction from the high-temperature zone and annealing zone of the kiln body to the kiln outlet, the distance between two adjacent temperature zones is greater than or equal to 1 m and less than or equal to 3 m.

[0010] Optionally, along the length direction of each temperature zone, the spacing between two adjacent upper air inlet pipes and the spacing between two adjacent lower air inlet pipes is less than or equal to 16 cm.

[0011] Optionally, the diameters of the upper air inlet pipe and the lower air inlet pipe are 60 to 100 mm.

[0012] Optionally, the upper air inlet pipe and the lower air inlet pipe are both made of reaction-sintered silicon carbide material.

[0013] According to the second aspect of the present invention, a control method for an automatic cooling system for microcrystalline glass production is provided, comprising: monitoring the upper real-time temperature and / or the lower real-time temperature in each temperature section in real time through a plurality of temperature sensors arranged corresponding to each temperature section, and transmitting the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature in each temperature section to a PLC control module; the PLC control module receives the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature in each temperature section, and based on the preset fan triggering condition, if the upper real-time temperature and / or the lower real-time temperature in a certain temperature section meets the preset fan triggering condition, the PLC control module calculates the corresponding frequency control parameter, and sends the output signal of the corresponding frequency control parameter to the corresponding upper fan inverter and / or the lower fan inverter, and the corresponding upper fan inverter and / or the lower fan inverter After the machine frequency converter responds to the output signal of the PLC control module, it executes frequency conversion control of the corresponding upper layer heat extraction fan and / or lower layer heat extraction fan; when the upper layer heat extraction fan and / or the lower layer heat extraction fan are working, the speed of the upper layer heat extraction fan and / or the lower layer heat extraction fan is automatically adjusted according to the frequency control parameters responded by the upper layer fan frequency converter and / or the lower layer fan frequency converter, and the impellers of the upper layer heat extraction fan and / or the lower layer heat extraction fan rotate, so that a low pressure area is formed inside the upper layer heat extraction fan and / or the lower layer heat extraction fan. When the pressure of the external air is higher than the pressure of the low pressure area, the external air is introduced through the air inlet end of the upper layer air inlet pipe and / or the lower layer air inlet pipe, and the external air passes through the upper layer air inlet pipe and / or the lower layer air inlet pipe for indirect heat exchange, and then is discharged through the upper layer main air duct / or the lower layer main air duct and the exhaust end of the upper layer heat extraction fan and / or the lower layer heat extraction fan to achieve the purpose of temperature control balance.

[0014] Optionally, the preset fan triggering condition is: when the upper layer real-time temperature and / or the lower layer real-time temperature in a certain temperature zone exceeds the set temperature by 0.5°C, the upper layer heat extraction fan and / or the lower layer heat extraction fan starts.

[0015] According to the third aspect of the present invention, a roller kiln is provided for use in the production of microcrystalline glass, comprising: a kiln body, a furnace cavity, a conveying device, and an automatic cooling system for indirectly cooling the high-temperature zone and annealing zone of the kiln body. The automatic cooling system is an automatic cooling system for the production of microcrystalline glass as described above.

[0016] Optionally, it also includes a nucleation heating zone, a kiln inlet and a heating device. The kiln inlet and the kiln outlet are respectively provided at the head and tail of the kiln body. The kiln body is sequentially provided with a nucleation heating zone, a high temperature zone and an annealing zone from the kiln inlet to the kiln outlet. The conveying device is used to convey the microcrystalline glass material from the kiln inlet to the kiln outlet in the furnace cavity. A heating device is provided in the high temperature zone and the annealing zone of the kiln body, and a heating device is arranged correspondingly below the upper air inlet pipe and above the lower air inlet pipe.

[0017] The advantages and beneficial effects of the present invention are as follows: the present invention provides an automatic cooling system for the production of microcrystalline glass, a control method thereof and a roller kiln. The automatic cooling system can realize indirect cooling treatment of the high-temperature zone and annealing zone of the kiln body through the joint action of a PLC control module, an upper heat extraction structure, a lower heat extraction structure, a main air duct, an upper air inlet duct, a lower air inlet duct and a temperature sensor, so as to achieve the purpose of temperature control balance; by adopting a material with high thermal conductivity, high temperature resistance and not easy to deform to make the upper air inlet duct and the lower air inlet duct, the purpose of steady and uniform cooling can be achieved, so as to ensure the stability and consistency of the product; by dividing the length from the high-temperature zone and annealing zone of the kiln body to the kiln outlet into multiple temperature zones and optimizing the length direction of each temperature zone respectively. The spacing between two adjacent temperature zones, the spacing between two adjacent upper air inlet ducts and two adjacent lower air inlet ducts, and the diameters of the upper air inlet ducts and the lower air inlet ducts can effectively reduce the temperature difference between each temperature zone. It can not only effectively control the problems of warping, cracking, cold cracking, etc. that are prone to occur in the annealing process of microcrystalline glass, thereby achieving the purpose of improving product quality, but also solve the process fluctuations caused by the heat release of the product itself during the crystallization process, which affect product performance, thereby ensuring the stability and consistency of the product during continuous production; by setting the fan triggering conditions, and when the real-time temperature meets the preset fan triggering conditions, the upper heat extraction fan and / or the lower heat extraction fan can operate at a low frequency, with low operating costs, low actual energy consumption, and excellent temperature control effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the roller kiln of the present invention.

[0019] Figure 2 This is a front view of a roller kiln equipped with an automatic cooling system according to the present invention.

[0020] Figure 3 A side view of a roller kiln equipped with an automatic cooling system according to the present invention.

[0021] Figure 4 1 is a temperature curve comparison diagram of Example 1 and Comparative Example 1 of the present invention.

[0022] Figure numerals: kiln body 1, high temperature zone and annealing zone 101, nucleation temperature rising zone 102, kiln inlet 103, kiln outlet 104, upper layer heat extraction blower 2, lower layer heat extraction blower 3, air inlet end 4, upper layer air inlet pipe 5, lower layer air inlet pipe 6, conveying device 7, heating device 8, lower layer main air duct 9, upper layer main air duct 10, exhaust end 11. DETAILED DESCRIPTION

[0023] The embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and are not to be construed as limitations on the present application. In addition, the following embodiments and features in the embodiments may be combined with each other unless there is a conflict. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0024] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; and internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on the specific circumstances.

[0025] Reference Attachment Figure 1-3 , an automatic cooling system for microcrystalline glass production, mainly composed of a PLC control module, an upper heat extraction structure, a lower heat extraction structure, an upper air inlet pipe and a lower air inlet pipe.

[0026] The existing microcrystalline glass production process is as follows: the glass matrix enters the furnace cavity in batches and continuously from the kiln inlet 103 of the kiln body 1, is transported by the conveying device 7 to the nucleation heating zone 102 to continuously absorb heat and form a crystal nucleus, and then is transported to the high temperature zone to realize the growth process of the crystal nucleus. After the crystallization is completed, it is transported to the annealing zone to form a microcrystalline glass product. In this process, when the matrix glass is in the high temperature zone, the batch products continue to release heat during the crystallization process. There is a situation where the heat released by the head product is inconsistent with the heat effect on the middle product and the tail product. According to the actual test data and product performance data, the reason is that the product is in a state of motion, resulting in the largest heat accumulation in the middle product, followed by the tail product, and the smallest in the head product. Therefore, in order to ensure the cooling effect, the automatic cooling system involved in this application covers the high temperature zone and annealing zone 101 of the kiln body 1, which is used to control the temperature balance to ensure product stability and consistency.

[0027] In order to fully cover the high temperature zone and annealing zone 101 of the kiln body 1, so as to achieve the purpose of temperature control balance and ensure product stability and consistency. The present application divides the kiln body 1 into multiple temperature zones along the length from the high temperature zone and annealing zone to the kiln outlet 104, and each temperature zone is provided with an upper heat extraction structure and a lower heat extraction structure, and the upper air inlet pipe 5 and the lower air inlet pipe 6 are respectively arranged above and below the furnace cavity, and the air inlet ends 4 of the upper air inlet pipe 5 and the lower air inlet pipe 6 respectively pass through the kiln body 1 in the vertical direction and extend outward, and are respectively connected to the upper heat extraction structure and the lower heat extraction structure, wherein, by providing an upper heat extraction structure and a lower heat extraction structure in each temperature zone, and the upper heat extraction structure and the lower heat extraction structure are controlled separately, so as to effectively reduce the temperature difference between the temperature zones and improve the temperature control effect; at the same time, by using the heat exchanger for conveying the microcrystalline glass material An upper air inlet pipe 5 and a lower air inlet pipe 6 are respectively arranged on the upper and lower sides of the conveying device 7. Compared with the defects of the existing structure, the present application is based on the temperature sensitivity requirements of the microcrystalline glass. By setting the upper air inlet pipe 5 and the lower air inlet pipe 6, the upper air inlet pipe 5 and the lower air inlet pipe 6 are respectively arranged above and below the furnace cavity, and are respectively connected to the upper heat extraction structure and the lower heat extraction structure. When the real-time temperature in a certain temperature zone exceeds the preset temperature range of the set temperature, the exhaust of the upper heat extraction structure and / or the lower heat extraction structure is started, which can better and evenly reduce the control temperature so as to make the entire cooling process more stable, which is beneficial to control the problems such as warping, cracking, cold cracking, etc. that are easily caused by the microcrystalline glass during the annealing process, thereby improving product quality.

[0028] According to one embodiment of the present application, in order to ensure the cooling effect, the upper air inlet pipe 5 and the lower air inlet pipe 6 involved in the present application are made of materials with high thermal conductivity, high temperature resistance and not easy to deform. Preferably, the upper air inlet pipe 5 and the lower air inlet pipe 6 are made of reaction-sintered silicon carbide material. By using high thermal conductivity reaction-sintered silicon carbide as the air inlet pipe, and connecting it to the upper heat extraction fan 2 and / or the lower heat extraction fan 3 through the upper main air duct 10 and / or the lower main air duct 9 respectively, the indirect cooling function of the heat exchange principle can be realized to achieve the purpose of smooth and uniform cooling, and ensure the stability and consistency of the product.

[0029] According to an embodiment of the present application, in order to further control the problems of warping, bursting, cold cracking, etc. that are easy to cause in the annealing process of microcrystalline glass, improve the quality of the product, and further solve the process fluctuations caused by the heat release of the product itself during the crystallization process that affect the product performance, thereby ensuring the stability and consistency of the product during continuous production, the present application also optimizes the structure and spatial layout of the spacing between the two temperature zones, the spacing between the two adjacent upper air inlet pipes 5 and the spacing between the two adjacent lower air inlet pipes 6, and the diameters of the upper air inlet pipe 5 and the lower air inlet pipe 6. Specifically, along the length direction of the high-temperature zone and annealing zone of the kiln body 1 to the kiln outlet 104, the adjacent two temperature zones are arranged at a first preset spacing; along the length direction of each temperature zone, the adjacent two upper air inlet pipes 5 and the adjacent two lower air inlet pipes 6 are distributed at a second preset spacing, and the diameters of the upper air inlet pipe 5 and the lower air inlet pipe 6 are set according to the preset diameters; preferably , along the length direction of the high-temperature zone and annealing zone of the kiln body 1 to the kiln outlet 104, the spacing between two adjacent temperature zones is greater than or equal to 1m and less than or equal to 3m; along the length direction of each temperature zone, the spacing between two adjacent upper air inlet pipes 5 and between two adjacent lower air inlet pipes 6 is less than or equal to 16cm; the diameters of the upper air inlet pipes 5 and the lower air inlet pipes 6 are 60-100mm; by structurally optimizing the spacing between the two temperature zones, the spacing between two adjacent upper air inlet pipes 5 and between two adjacent lower air inlet pipes 6, and the diameters of the upper air inlet pipes 5 and the lower air inlet pipes 6 and optimizing the spatial layout, the temperature difference between each temperature zone can be effectively reduced, and the temperature difference between each temperature zone can be controlled within ±1°C, so as to effectively control the warping, cracking, cold cracking and other problems that are easy to cause in the annealing process of microcrystalline glass, and at the same time solve the process fluctuations caused by the heat release of the product itself during the crystallization process, which affect the product performance, so as to achieve the purpose of improving product quality.

[0030] According to one embodiment of the present application, in order to achieve the indirect cooling function of the heat exchange principle while ensuring the temperature control effect, and to effectively reduce energy consumption and operating costs, the upper heat extraction structure involved in the present application includes an upper fan inverter (not shown), an upper heat extraction fan 2 electrically connected to the upper fan inverter, and an upper main air duct 10; the lower heat extraction structure includes a lower fan inverter (not shown), a lower heat extraction fan 3 electrically connected to the lower fan inverter, and a lower main air duct 9; the air inlet ends 4 of the upper heat extraction fan 2 and the lower heat extraction fan 3 are respectively connected to the upper air inlet duct 5 and the lower air inlet duct 6 embedded in the kiln body 1 through the upper main air duct 10 and the lower main air duct 9; the upper fan inverter and the lower fan inverter are respectively electrically connected to the PLC control module, and the corresponding upper heat extraction fan 2 and / or lower heat extraction fan 3 are controlled by frequency conversion to achieve the purpose of temperature control balance.

[0031] According to one embodiment of the present application, each temperature zone is provided with a plurality of temperature sensors electrically connected to the PLC control module, which are used to monitor the upper real-time temperature and / or the lower real-time temperature of each temperature zone in real time, and transmit the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature to the PLC control module.

[0032] According to one embodiment of the present application, the present application collects the upper real-time temperature and / or the lower real-time temperature of the corresponding temperature zone through multiple temperature sensors arranged in each temperature zone, and transmits the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature to the PLC control module. The PLC control module performs logical judgment and judges whether the upper real-time temperature and / or the lower real-time temperature in each temperature zone meets the preset fan trigger condition based on the preset fan trigger condition. It should be noted that the fan trigger condition is specifically a preset temperature threshold, such as the set temperature ±2°C. The PLC control module performs logical judgment and mainly judges whether the upper real-time temperature and / or the lower real-time temperature in each temperature zone is within the range of the set temperature ±2°C. If it exceeds the range of the set temperature ±2°C, the PLC control module calculates the corresponding frequency control parameter and outputs it to the The corresponding upper fan frequency converter and / or lower fan frequency converter, after responding to the output signal of the PLC control module, executes the variable frequency control of the corresponding upper heat extraction fan 2 and / or lower heat extraction fan 3; in addition, in order to further reduce energy consumption and the operating cost of the fan, it can be achieved by further reducing the control range of the temperature threshold, such as setting the temperature ±0.5℃, and continuous control can be performed according to the process temperature curve, so that the upper real-time temperature and the lower real-time temperature in each temperature zone are always within the control range. When the upper real-time temperature and / or the lower real-time temperature in a certain temperature zone exceeds the range of the set temperature ±0.5℃, the corresponding upper heat extraction fan 2 and / or the lower heat extraction fan 3 starts to work and operates at a low frequency, so as to achieve the purpose of low operating cost, low actual energy consumption and excellent temperature control effect.

[0033] According to one embodiment of the present application, the PLC control module involved in the present application may include two modes, namely manual mode and automatic mode. Through the control methods of the two modes, the operability of the process can be improved, and the debugging and troubleshooting of the equipment can be facilitated.

[0034] According to one embodiment of the present application, the present application also provides a control method for an automatic cooling system for microcrystalline glass production, comprising the following steps: monitoring the upper real-time temperature and / or the lower real-time temperature in each temperature section in real time through a plurality of temperature sensors arranged corresponding to each temperature section, and transmitting the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature in each temperature section to a PLC control module; the PLC control module receives the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature in each temperature section, and based on the preset fan triggering condition, if the upper real-time temperature and / or the lower real-time temperature in a certain temperature section meets the preset fan triggering condition, the PLC control module calculates the corresponding frequency control parameter, and sends the output signal of the corresponding frequency control parameter to the corresponding upper fan inverter and / or the lower fan inverter, and the corresponding upper fan inverter and / or the lower fan inverter responds After receiving the output signal of the PLC control module, the frequency conversion control of the corresponding upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 is executed; when the upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 are working, the speed of the upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 is automatically adjusted according to the frequency control parameters responded by the upper layer fan frequency converter and / or lower layer fan frequency converter, and the impeller of the upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 rotates, so that the upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 are automatically adjusted. 2 and / or the lower heat extraction fan 3 form a low-pressure area. When the pressure of the external air is higher than that of the low-pressure area, the external air is introduced through the air inlet end 4 of the upper air inlet pipe 5 and / or the lower air inlet pipe 6. After the external air passes through the upper air inlet pipe 5 and / or the lower air inlet pipe 6 for indirect heat exchange, it is discharged through the upper main air duct 10 / or the lower main air duct 9, the upper heat extraction fan 2 and / or the lower heat extraction fan 3 exhaust end 11 to achieve the purpose of temperature control balance.

[0035] According to one embodiment of the present application, the present application also provides a roller kiln for use in the production of microcrystalline glass, comprising: a kiln body 1, a furnace cavity, a conveying device 7, and an automatic cooling system for indirectly cooling the high-temperature zone and annealing zone 101 of the kiln body 1, wherein the automatic cooling system is an automatic cooling system for the production of microcrystalline glass as described.

[0036] According to one embodiment of the present application, the roller kiln further includes a nucleation heating zone 102, a kiln inlet 103 and a heating device 8. The kiln inlet 103 and the kiln outlet 104 are respectively provided at the head and tail of the kiln body 1. The kiln body 1 is sequentially provided with a nucleation heating zone 102, a high temperature zone and an annealing zone 101 from the kiln inlet 103 to the kiln outlet 104. The conveying device 7 is used to convey the microcrystalline glass material from the kiln inlet 103 to the kiln outlet 104 in the furnace cavity. The heating device 8 is provided in the high temperature zone and the annealing zone 101 of the kiln body 1, and a heating device 8 is arranged correspondingly below the upper air inlet pipe 5 and above the lower air inlet pipe 6. Furthermore, the heating device 8 is a resistance wire. Through the radiation heating principle of the resistance wire, the temperature in the high temperature zone and the annealing zone 101 can reach 1000°C, which is used to provide conditions for the nucleation and crystallization process. At the same time, the conveying device 7 involved in the present application is a ceramic transmission roller, which is used to convey the microcrystalline glass material under high temperature conditions.

[0037] The present invention will be further described below with reference to Examples 1 to 8 and Comparative Example 1.

[0038] Example 1: This embodiment discloses a roller kiln including the aforementioned automatic cooling system. By setting a control program for fan triggering conditions, when the real-time temperature of the upper layer and / or the real-time temperature of the lower layer in a certain temperature zone exceeds the set temperature by ±0.5°C, the corresponding upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 are activated. The crystallization process includes: when the base glass Y is driven from the kiln inlet 103 by ceramic drive rollers through the nucleation heating zone 102 to the high temperature zone and annealing zone 101, the base glass Y releases heat during the crystallization growth process. The temperature sensor monitors the real-time temperature in real time and transmits the real-time temperature output signal to the PLC control module. Based on the preset fan triggering conditions, the PLC control module performs logical judgment. If the temperature exceeds the range of ±0.5°C of the set temperature, the PLC control module calculates the corresponding frequency control parameters and outputs them to the corresponding upper layer fan inverter and / or lower layer fan inverter. In response to the output signal of the PLC control module, the corresponding upper layer fan inverter and / or lower layer fan inverter executes the corresponding upper layer heat extraction. The frequency conversion control of the fan 2 and / or the lower layer heat extraction fan 3 automatically adjusts the rotation speed of the upper layer heat extraction fan 2 and / or the lower layer heat extraction fan 3 according to the frequency control parameters of the upper layer fan frequency converter and / or the lower layer fan frequency converter. The impellers of the upper layer heat extraction fan 2 and / or the lower layer heat extraction fan 3 rotate, so that a low pressure area is formed inside the upper layer heat extraction fan 2 and / or the lower layer heat extraction fan 3. When the pressure of the external air is higher than the pressure of the low pressure area, the external air is introduced from the air inlet end 4 of the upper layer air inlet pipe 5 and / or the lower layer air inlet pipe 6, and then discharged from the air outlet end 11 of the upper layer heat extraction fan 2 and / or the lower layer heat extraction fan 3. The air temperature in the air duct in the kiln exchanges heat with the temperature in the kiln to achieve the purpose of cooling; then the product is discharged from the kiln outlet 104. The overall process temperature curve is stable, refer to the attached Figure 4 , attached Figure 4 This is a comparison of the temperature curves for Example 1 and Comparative Example 1 (i.e., without the cooling system). The glass-ceramics were free of cracks after exiting the kiln. The glass-ceramics at the head, middle, and tail were tested for grain size and transmittance. The test results are shown in Table 1.

[0039] Example 2: This example involves the same automatic cooling system, roller kiln, and crystallization process as Example 1. The difference lies in the control program for setting the fan trigger conditions: when the real-time temperature of the upper layer and / or the real-time temperature of the lower layer within a certain temperature zone exceeds the set temperature by ±2°C, the corresponding upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 are activated. The glass-ceramics were free of cracks after exiting the kiln. The grain size and transmittance of the glass-ceramics were tested at the head, middle, and tail of the glass-ceramics. The test results are shown in Table 1.

[0040] Example 3: This example involves the same automatic cooling system, roller kiln, and crystallization process as Example 1. The difference lies in the control procedure for setting the fan trigger conditions: when the upper layer real-time temperature and / or the lower layer real-time temperature within a certain temperature zone exceeds the set temperature by ±0.5°C, the corresponding upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 in the high temperature zone is activated, while the corresponding upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 in the annealing zone is deactivated. After leaving the kiln, 0.25% of the glass-ceramics exhibited cracks. The glass-ceramics at the head, middle, and tail were tested for grain size and transmittance. The test results are shown in Table 1.

[0041] Example 4: This example involves the same automatic cooling system, roller kiln, and crystallization process as Example 1. The difference lies in the control procedure for setting the fan trigger conditions: when the upper layer real-time temperature and / or the lower layer real-time temperature within a certain temperature zone exceeds the set temperature by ±0.5°C, the corresponding upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 in the annealing zone begins to operate, and the corresponding upper layer heat extraction fan 2 and / or lower layer heat extraction fan 3 in the high-temperature zone is activated at 50%. The glass-ceramics were free of cracks after exiting the kiln. The glass-ceramics at the head, middle, and tail were tested for grain size and transmittance. The test results are shown in Table 1.

[0042] In Examples 5 to 7, referring to Example 1, experiments were conducted using the same crystallization process and cooling control process, but with different air inlet pipe diameters and spacings. For details, refer to Table 1.

[0043] Comparative Example 1: The roller kiln and crystallization process involved in this comparative example are the same as those in Example 1, except that the automatic cooling system is not turned on. Figure 4The crystallization process in this comparative example exhibited significant fluctuations in the overall exothermic curve. After leaving the kiln, 0.37% of the glass-ceramics exhibited cracks. Grain size and transmittance were measured at the head, middle, and tail of the glass-ceramics. The test results are shown in Table 1.

[0044] Table 1 Experimental data and test results of Examples 1 to 8 and Comparative Example 1

[0045] serial number Product thickness (mm) Set temperature curve exhaust fan Air inlet pipe diameter (mm) Average grain size (nm) Transmittance at 550nm Other situations Example 1 0.64mm A All are turned on automatically, the upper and lower heat extraction fans in a single temperature zone are controlled separately, and the distance between each air inlet pipe is 16cm 60～100 24.5 91.07％ Glass-ceramic products are free of cracks and warping Example 2 0.64mm A All are turned on automatically, the upper and lower heat extraction fans in a single temperature zone are controlled separately, and the distance between each air inlet pipe is 16cm 60～100 25.4 90.94％ Glass-ceramic products are free of cracks and warping Example 3 0.64mm A The hot air blower in the high temperature zone is turned on, the hot air blower in the annealing zone is not turned on, the upper and lower hot air blowers in the single temperature zone are controlled separately, and the distance between each air inlet pipe is 16cm 60～100 24.3 91.11％ 0.25% of glass-ceramic products have cracks but no warping Example 4 0.64mm A The hot air blower in the high temperature zone is turned on 50%, the hot air blower in the annealing zone is fully turned on, the upper and lower hot air blowers in the single temperature zone are controlled separately, and the distance between each air inlet pipe is 16cm 60～100 27.7 90.56％ Glass-ceramic products are free of cracks and warping Example 5 0.64mm A All are turned on automatically, the upper and lower heat extraction fans in a single temperature zone are controlled separately, and the distance between each air inlet pipe is 20cm 60～100 28.6 90.22% 1.5% of glass-ceramic products have cracks but no warping Example 6 0.64mm A All are automatically controlled, the upper and lower heat extraction fans in a single temperature zone are controlled separately, and the distance between each air inlet pipe is 14cm 60～100 23.66 91.06% Glass-ceramic products are free of cracks and warping Example 7 0.64mm A All are turned on automatically, the upper and lower heat extraction fans in a single temperature zone are controlled separately, and the distance between each air inlet pipe is 16cm ＞100 27.6 90.10% 0.5% of glass-ceramic products have cracks and warping Comparative Example 1 0.64mm A Without turning on the automatic cooling system, the distance between the air inlet pipes is 16cm 60～100 34.6 89.88％ 0.37% of glass-ceramic products have cracks and warping

[0046] As can be seen from Table 1, under the same crystallization process conditions, taking Example 1 as an example, when the exhaust fans of the high temperature zone and the annealing zone 101 are all turned on and automatically controlled, the temperature fluctuation of the crystallization process is stable and can be controlled within the range of ±1°C, the microcrystalline glass products have consistency, and the average grain size and 550nm visible light transmittance meet the quality requirements; when the exhaust fan is not turned on (Comparative Example 1), the average grain size is larger and the transmittance is lower than 90%. Figure 4 From the exothermic data, it can be seen that the maximum temperature fluctuation of the crystallization process is 13°C. Therefore, the stability and consistency of the microcrystalline glass products are not good. In addition, it can be seen from Examples 5 to 7 that when the distance between the air inlet pipes is less than or equal to 16 cm and the diameter of the air inlet pipes is 60-100 mm, the quality of the microcrystalline glass products is the best, the average grain size can be effectively controlled, and quality problems such as warping, cracks, and optics can be effectively suppressed. It can be seen from Examples 1 and 7 that under the conditions of all automatic controls, separate control of the upper and lower heat extraction fans in a single temperature zone, and a distance of 16 cm between the air inlet pipes, when the diameter of the air inlet pipe is greater than 100 mm, since the heat treatment capacity of microcrystalline glass in the mass production process is calculated based on hundreds of thousands of pieces of microcrystalline glass per day, combined with the test results of Example 7, it can be seen that 0.5% of the microcrystalline glass products have cracks after leaving the kiln, which is a high proportion, and there are both cracks and warping defects. Therefore, there are problems such as poor thermal insulation of the kiln body 1, rapid heat loss, and difficulty in installing the air inlet pipe, resulting in poor quality of the microcrystalline glass products, which are prone to warping, cracks, optics and other quality problems.

[0047] The above content is a further detailed description of the present invention in conjunction with specific embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. An automatic cooling system for glass-ceramics production, characterized in that: The automatic cooling system includes: a PLC control module, an upper heat extraction structure electrically connected to the PLC control module and having an exhaust function, a lower heat extraction structure electrically connected to the PLC control module and having an exhaust function, an upper air inlet pipe and a lower air inlet pipe. The kiln body is divided into multiple temperature zones along the length from the high-temperature zone and annealing zone to the kiln outlet. An upper heat extraction structure and a lower heat extraction structure are provided in each temperature zone. The upper air inlet pipe and the lower air inlet pipe are respectively arranged above and below the furnace cavity. The air inlet ends of the upper air inlet pipe and the lower air inlet pipe respectively penetrate the kiln body in the vertical direction and extend outward, and are respectively connected to the upper heat extraction structure and the lower heat extraction structure. When the real-time temperature in a certain temperature zone exceeds the preset temperature range of the set temperature, the exhaust of the upper heat extraction structure and / or the lower heat extraction structure is started.

2. The automatic cooling system for producing glass-ceramics according to claim 1, characterized in that: The upper heat extraction structure includes an upper fan frequency converter, an upper heat extraction fan electrically connected to the upper fan frequency converter, and an upper main air duct. The lower heat extraction structure includes a lower fan frequency converter, a lower heat extraction fan electrically connected to the lower fan frequency converter, and a lower main air duct. The air inlet ends of the upper heat extraction fan and the lower heat extraction fan are respectively connected to the upper air inlet duct and the lower air inlet duct embedded in the kiln body through the upper main air duct and the lower main air duct. The upper fan frequency converter and the lower fan frequency converter are respectively electrically connected to the PLC control module to control the frequency conversion of the corresponding upper heat extraction fan and / or the lower heat extraction fan to achieve the purpose of temperature control balance.

3. The automatic cooling system for producing glass-ceramics according to claim 2, characterized in that: Each temperature zone is provided with a plurality of temperature sensors electrically connected to the PLC control module for real-time monitoring of the upper real-time temperature and / or the lower real-time temperature of each temperature zone, and transmitting the output signal of the upper real-time temperature and / or the output signal of the lower real-time temperature to the PLC control module.

4. The automatic cooling system for producing glass-ceramics according to claim 1, characterized in that: Along the length direction of the kiln body from the high temperature zone and annealing zone to the kiln outlet, the distance between two adjacent temperature zones is greater than or equal to 1m and less than or equal to 3m.

5. The automatic cooling system for producing glass-ceramics according to claim 1, characterized in that: Along the length direction of each temperature zone, the spacing between two adjacent upper air inlet pipes and between two adjacent lower air inlet pipes is less than or equal to 16 cm.

6. The automatic cooling system for producing glass-ceramics according to claim 1, characterized in that: The diameters of the upper air inlet pipe and the lower air inlet pipe are 60 to 100 mm.

7. The automatic cooling system for producing glass-ceramics according to claim 1, characterized in that: The upper air inlet pipe and the lower air inlet pipe are both made of reaction-sintered silicon carbide material.

8. The control method of an automatic cooling system for producing glass-ceramics according to any one of claims 1 to 7, characterized in that: include: The upper layer real-time temperature and / or the lower layer real-time temperature in each temperature zone are monitored in real time by multiple temperature sensors arranged in each temperature zone, and the output signal of the upper layer real-time temperature and / or the lower layer real-time temperature in each temperature zone is transmitted to the PLC control module; The PLC control module receives the output signal of the upper layer real-time temperature and / or the output signal of the lower layer real-time temperature in each temperature section. Based on the preset fan triggering condition, if the upper layer real-time temperature and / or the lower layer real-time temperature in a certain temperature section meet the preset fan triggering condition, the PLC control module calculates the corresponding frequency control parameter and sends the output signal of the corresponding frequency control parameter to the corresponding upper layer fan inverter and / or the lower layer fan inverter. After the corresponding upper layer fan inverter and / or the lower layer fan inverter responds to the output signal of the PLC control module, it executes the variable frequency control of the corresponding upper layer heat extraction fan and / or the lower layer heat extraction fan; When the upper layer heat extraction fan and / or the lower layer heat extraction fan are working, the rotation speed of the upper layer heat extraction fan and / or the lower layer heat extraction fan is automatically adjusted according to the frequency control parameters responded by the upper layer fan inverter and / or the lower layer fan inverter. The impellers of the upper layer heat extraction fan and / or the lower layer heat extraction fan rotate, so that a low pressure area is formed inside the upper layer heat extraction fan and / or the lower layer heat extraction fan. When the pressure of the external air is higher than the pressure of the low pressure area, the external air is introduced through the air inlet end of the upper layer air inlet pipe and / or the lower layer air inlet pipe. After the external air passes through the upper layer air inlet pipe and / or the lower layer air inlet pipe for indirect heat exchange, it is discharged through the upper layer main air duct and / or the lower layer main air duct and the exhaust end of the upper layer heat extraction fan and / or the lower layer heat extraction fan to achieve the purpose of temperature control balance.

9. The control method of the automatic cooling system for producing glass-ceramics according to claim 8, characterized in that: The preset fan triggering condition is: when the upper layer real-time temperature and / or the lower layer real-time temperature in a certain temperature section exceeds the set temperature ±0.5°C, the upper layer heat extraction fan and / or the lower layer heat extraction fan starts.

10. A roller kiln, characterized in that: Applied to the production of microcrystalline glass, it comprises: a kiln body, a furnace cavity, a conveying device and an automatic cooling system for indirectly cooling the high-temperature zone and annealing zone of the kiln body. It is characterized in that the automatic cooling system is an automatic cooling system for microcrystalline glass production as described in any one of claims 1-7.

11. A roller kiln according to claim 10, characterized in that: It also includes a nucleation heating zone, a kiln inlet and a heating device. The kiln inlet and the kiln outlet are respectively arranged at the head and tail of the kiln body. The kiln body is sequentially provided with a nucleation heating zone, a high temperature zone and an annealing zone from the kiln inlet to the kiln outlet. The conveying device is used to convey the microcrystalline glass material from the kiln inlet to the kiln outlet in the furnace cavity. A heating device is arranged in the high temperature zone and the annealing zone of the kiln body, and a heating device is arranged correspondingly below the upper air inlet pipe and above the lower air inlet pipe.

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