High-temperature electric tunnel kiln and working method thereof

Abstract

The invention discloses a high-temperature electric tunnel kiln and a working method thereof. The high-temperature electric tunnel kiln comprises a kiln body and an outer circulation line. A plurality of kiln holes are formed in the furnace body, operation guide rails are installed in the kiln holes, the operation directions of the operation guide rails are the same, the two ends of the outer circulation line are connected with the two ends of the operation guide rails respectively, a plurality of temperature control areas are arranged in the kiln holes, and the temperature control areas of the kiln holes completely coincide. The technical scheme of the porous equidirectional high-temperature electric tunnel kiln with the outer circulation lines and the multi-temperature-section control function for ceramic sintering is simple and easy to implement, application of complex process curves can be met, the temperature uniformity of the effective section of the kiln is improved, the fault rate of heating elements is reduced, and therefore the quality of ceramic products is improved, and the production cost is reduced. And meanwhile, the labor intensity of workers is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of ceramic sintering, in particular to a high-temperature electric tunnel kiln and a working method thereof. Background Art

[0002] Ceramic firing is a general term for the densification process and phenomenon of ceramic green bodies at high temperatures. This process affects the final properties of the ceramic, including its hardness, strength, density, thermal stability, and appearance texture. As the temperature rises and the time increases, the solid particles are bonded to each other, the grains grow, the voids (pores) and grain boundaries gradually decrease, and through the transfer of substances, the total volume shrinks, the density increases, and finally becomes a hard polycrystalline sintered body with a certain fiber structure.

[0003] In the ceramic sintering process, in order to achieve the ideal sintering effect, the temperature curve during the sintering process must be precisely controlled. It is necessary to set a suitable sintering curve based on the raw material characteristics, product performance, dimensional tolerance requirements, etc. to ensure that the sintered ceramic products meet the design requirements and have good performance stability.

[0004] The most commonly used high-temperature electric tunnel kiln structure is a double-hole reverse high-temperature electric tunnel kiln, such as Figure 1 As shown, there are only three temperature control zones in a single hole, and the adjustment of the ceramic sintering curve is limited. It cannot meet the design requirements of complex curves and is not conducive to ensuring product quality. The long-term working current in the high-temperature zone of the double-hole reverse high-temperature electric tunnel kiln is 180~200A, and the failure rate of the silicon-molybdenum rod (heating element) is high during use. In the temperature zone design of the double-hole reverse high-temperature electric tunnel kiln, the heating rods in the middle of the two kiln holes are staggered and connected in the middle. The actual temperature of the temperature zone will be affected by the temperature of the adjacent area of ​​the other kiln hole, resulting in a temperature field uniformity of ±5℃ in the effective cross-section of the kiln, which is quite different. During the operation of the double-hole reverse high-temperature electric tunnel kiln, the areas at both ends of the furnace body are the working areas for loading and unloading products. According to the progress of the kiln, workers need to frequently load and unload products, which is labor-intensive and affects production efficiency and product quality. Summary of the invention

[0005] The object of the present invention is to provide a high-temperature electric tunnel kiln and a working method thereof, so as to solve the problems of low production efficiency and product quality of the existing double-hole reverse high-temperature electric tunnel kiln.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A high-temperature electric tunnel kiln comprises a furnace body and an external circulation line; A plurality of kiln holes are provided in the furnace body, and running guide rails are installed in the plurality of kiln holes. The running directions of the plurality of running guide rails are the same. The two ends of the external circulation line are respectively connected to the two ends of the running guide rails. A plurality of temperature control zones are provided in the kiln holes, and the temperature control zones of the plurality of kiln holes completely overlap.

[0007] Furthermore, the number of temperature control zones in the kiln hole is 6 to 8, the temperature of each temperature control zone is different, and the working current in the temperature control zone is 120 to 140A.

[0008] Furthermore, the temperature field uniformity of the effective cross-section of the furnace body is ±2°C.

[0009] Furthermore, the temperature control zone is heated by a heating rod, and the heating rod is a silicon-molybdenum rod.

[0010] Furthermore, a circulating track is arranged on the outer circulating line, and the circulating track is connected to the running guide rail.

[0011] Furthermore, a heat-insulating layer is provided on the outer side of the furnace body.

[0012] Furthermore, two kiln holes are provided in the furnace body, and running guide rails are installed in the two kiln holes. The kiln is provided with an external circulation line, and the two ends of the two running guide rails are respectively connected to the two ends of the external circulation line.

[0013] Furthermore, four kiln holes are opened in the furnace body, and running guide rails are installed in the four kiln holes. The kiln is provided with two external circulation lines.

[0014] Furthermore, the kiln is provided with a first external circulation line and a second external circulation line, the two ends of the first external circulation line are respectively connected to the two ends of the two running guide rails, and the two ends of the second external circulation line are respectively connected to the two ends of the other two running guide rails.

[0015] A working method of the high temperature electric tunnel kiln, comprising: Start the kiln, the running rails and the external circulation line start to operate, place the ceramic body on the running rails, and the running rails deliver the ceramic body into the kiln hole steadily and accurately; The ceramic body passes through the temperature control zone in sequence to preheat and fire the ceramic body; After firing, the ceramic products are transported to the external circulation line, and after cooling, the ceramic products are centrally loaded and unloaded.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a high-temperature electric tunnel kiln, in which a plurality of kiln holes are provided in the kiln body, and running guide rails are installed in the kiln holes, so that the ceramic blank can move smoothly and accurately along the guide rails. The running directions of the plurality of running guide rails are the same, and the two ends of the outer circulation line are respectively connected to the two ends of the running guide rails to form a closed-loop material transmission system. The ceramic blank can be centrally loaded and unloaded on the outer circulation line, which reduces the number of manual operations and improves the working efficiency. A plurality of temperature control zones are provided in the kiln hole, and the temperature control zones of the plurality of kiln holes completely overlap. The temperature field in the entire furnace body is made more uniform, which is conducive to obtaining a consistent heat treatment environment for ceramic products during the firing process. At the same time, each temperature control zone can independently adjust the temperature, further improving the accuracy of temperature control, thereby ensuring the quality of ceramic products. The technical solution of the high-temperature electric tunnel kiln for ceramic sintering provided by the present invention, which has a multi-porous same-direction belt with an outer circulation line and multi-temperature segment control, is simple and easy to implement, can meet the application of complex process curves, improves the temperature uniformity of the effective cross-section of the kiln, reduces the failure rate of the heating element, thereby improving the quality of the ceramic product, and reducing the labor intensity of the workers. The high-temperature electric tunnel kiln of the present invention realizes efficient, stable and uniform firing of ceramic products through automated material transmission, precise temperature control and efficient heat insulation, thereby improving production efficiency and product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 This is a schematic diagram of the double-hole reverse high-temperature electric tunnel kiln currently in use.

[0019] Figure 2 It is a schematic diagram of a double-hole, same-direction high-temperature electric tunnel kiln in Example 1 of the present invention.

[0020] Figure 3 It is a schematic diagram of a four-hole same-direction high-temperature electric tunnel kiln in Example 2 of the present invention. DETAILED DESCRIPTION

[0021] 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. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0022] 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.

[0023] 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.

[0024] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does 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. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0025] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0026] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings: The present invention provides a high-temperature electric tunnel kiln, including a furnace body and an external circulation line. A plurality of kiln holes are provided in the furnace body, and running guide rails are installed in the plurality of kiln holes, so as to facilitate the transportation of ceramics to the temperature control zone for firing, which not only ensures that the ceramic blank is smoothly and accurately moved to the temperature control zone for preheating and firing, but also greatly improves the flexibility and production capacity of the automated production line. The running guide rail is made of high-strength, high-temperature resistant material, and can withstand long-term high-temperature operation without deformation, thereby ensuring the continuity and stability of production. The running directions of the plurality of running guide rails are the same, and the two ends of the external circulation line are respectively connected to the two ends of the running guide rails. A circulating track is provided on the external circulation line, and the circulating track is connected to the running guide rail to form a closed-loop material transmission system, which is convenient for centralized loading and unloading of products on the external circulation line, reduces the number of manual operations, improves work efficiency, and reduces the risk of damage caused by frequent moving.

[0028] There are several temperature control zones in the kiln hole, and the number of temperature control zones is 6 to 8. The temperature of each temperature control zone is different. These zones independently adjust the temperature through the temperature control system to ensure that the ceramics can obtain the most suitable heat treatment environment at different firing stages to meet the needs of ceramics at different firing stages. The temperature control zone is heated by a heating rod, which is a silicon-molybdenum rod. The silicon-molybdenum rod is used as a heating element not only because of its excellent high temperature resistance and stability, but also because it can quickly respond to temperature control instructions and achieve precise temperature control. The working current in the temperature control zone is 120~140A, which reduces the failure rate of the heating element during use. The temperature control zones of several kiln holes are completely overlapped, which is conducive to improving the temperature uniformity of the effective cross-section of the kiln, so that the temperature field uniformity of the effective cross-section of the furnace body is maintained at ±2℃, which provides a strong guarantee for the uniform firing of ceramic products. The outer side of the furnace body is provided with an insulation layer, which is made of high-efficiency thermal insulation material, which effectively reduces the heat loss, not only improves the energy utilization efficiency, but also reduces the influence of the external environment on the temperature in the furnace, ensures the stability of the firing process, and avoids quality problems caused by temperature fluctuations.

[0029] Working method of the high temperature electric tunnel kiln of the present invention: Start the kiln, the running rails and the outer circulation line start to operate, and the ceramic blanks are placed on the running rails. These rails are made of high-strength, high-temperature resistant materials to ensure long-term operation in a high-temperature environment without deformation. The running rails deliver the ceramic blanks into the kiln hole steadily and accurately; The ceramic bodies pass through the temperature control area in turn. These kiln holes are equipped with tracks that are consistent with the direction of the running guide rails to ensure that the bodies can smoothly enter the preheating and firing areas for preheating and firing of the ceramic bodies. The outer circulation line is connected to the running guide rail through a circulating track to form a closed-loop material transmission system. After firing, the ceramic products are transported to the outer circulation line. After cooling, the ceramic products are centrally loaded and unloaded on the outer circulation line.

[0030] The present invention will be further described below by means of specific embodiments: Embodiment 1: like Figure 2 As shown, the kiln of this embodiment is a double-hole same-direction high-temperature electric tunnel kiln, with two kiln holes in the furnace body, and running guide rails are installed in the two kiln holes, and the running directions of the two running guide rails are the same. This embodiment is designed with an outer circulation line, and a circulation track is set on the outer circulation line. The two ends of the outer circulation line are connected with the two ends of the two running guide rails to form a closed-loop material transmission system, which realizes the centralized loading and unloading of products on the outer circulation line. And according to the sintering time of the product, the length of the outer circulation line body is designed, and finally it can be realized that the operator loads and unloads the product during the day, and the loaded product can meet the continuous operation requirements of the equipment. The night shift only needs to observe the operation status of the equipment, which effectively reduces the labor intensity of the workers and reduces the impact of human factors on product quality.

[0031] In order to solve the problem that the traditional double-hole electric tunnel kiln has fewer temperature zones and limited adjustment of the ceramic sintering curve, 6 temperature control zones are set according to the ceramic sintering requirements. The temperature of each temperature control zone is different, which can realize the multi-temperature section control of the ceramic sintering process and flexibly adjust the sintering curve to meet the application of complex process curves. The temperature control zones of the two kiln holes completely overlap and are not affected by the temperature of the other kiln hole, so that the temperature field uniformity of the effective cross-section of the kiln is maintained at ±2℃, with a small difference, which can better guarantee the product quality.

[0032] By adjusting the sintering curve of the double-hole co-directional high-temperature electric tunnel kiln, the working current of the temperature control zone can be reduced. Its working current is 120A, which significantly reduces the breaking frequency of the heating rod. The outer side of the furnace body is provided with a heat preservation layer made of high-efficiency heat-insulating materials, which effectively reduces the heat loss and ensures the stability of the firing process.

[0033] The double-hole, same-direction high-temperature electric tunnel kiln of this embodiment has a uniform temperature field and a flexible temperature control zone design, which makes the sintered ceramic products have better dimensional consistency. When put into the field of ceramic sintering, the sintered ceramic products have good dimensional consistency, and the proportion of defective products such as dimensional tolerance and roundness tolerance is significantly reduced, thereby improving the overall quality and market competitiveness of the products.

[0034] Six temperature control zones are set, and the temperature of each temperature control zone is independently adjustable, which greatly improves the multi-temperature section control capability of the ceramic sintering process. This design allows flexible adjustment of the sintering curve to meet the needs of different complex process curves and improve the diversity and quality of the products. The improvement of multi-temperature section control capability enables the kiln to adapt to the needs of more types of ceramic products and complex process curves, broadening the application field and market scope. The temperature control zones of the two kiln holes completely overlap, ensuring that the uniformity of the temperature field of the effective cross-section of the kiln is maintained at ±2°C, greatly reducing the impact of temperature differences on product quality. This highly uniform temperature field is crucial to improving the dimensional consistency of ceramic products and reducing the proportion of defective products. The low-energy design and efficient thermal insulation layer enable the kiln to significantly reduce energy consumption and carbon emissions during the sintering process, which is in line with the development trend of green production.

[0035] The closed-loop material transmission system is adopted, and the centralized loading and unloading of products on the outer circulation line is realized through the connection between the outer circulation line and the running guide rail. This design not only improves the loading and unloading efficiency, but also ensures the continuity and stability of material transmission, and reduces interruption and waiting time. The closed-loop material transmission system and flexible temperature control zone design improve the automation and continuity of the production process, reduce the interference of human factors and waiting time, and thus improve the overall production efficiency.

[0036] Embodiment 2: like Figure 3 As shown, based on the design of the double-hole co-directional high-temperature electric tunnel kiln in Example 1, a four-hole co-directional high-temperature electric tunnel kiln is designed. The four-hole co-directional high-temperature electric tunnel kiln sets 6 temperature control zones, and the temperature control zones of the four kiln holes completely overlap, and the kiln hole temperature has little effect on ceramic sintering. Multi-temperature section control of the ceramic sintering process can be achieved, and the sintering curve can be flexibly adjusted to meet the application of complex process curves.

[0037] In order to meet the needs of product loading and continuous operation of equipment, this embodiment designs two external circulation lines, including a first external circulation line and a second external circulation line. Running guide rails are installed in the four kiln holes. The two ends of the first external circulation line are respectively connected to the two ends of two of the running guide rails, and the two ends of the second external circulation line are respectively connected to the two ends of the other two running guide rails, forming two closed-loop material transmission systems, which can meet the needs of loading and unloading products during the day and observing the equipment operation status at night, thereby reducing the labor intensity of workers.

[0038] Compared with using two double-hole co-directional high-temperature electric tunnel kilns, the use of two sets of insulation materials on the outside of the furnace body is reduced, and the waste heat of the equipment can be utilized, so that the overall energy consumption of the four-hole co-directional high-temperature electric tunnel kiln is reduced by about 20% compared with the energy consumption of two double-hole co-directional high-temperature electric tunnel kilns.

[0039] This embodiment is not only a simple extension of the double-hole electric tunnel kiln, but also finds a balance between energy conservation and emission reduction, production efficiency and process flexibility. By accurately planning six temperature control zones and ensuring that the temperature control areas of the four kiln holes completely overlap, the impact of the temperature difference between the kiln holes on the quality of ceramic sintering is greatly reduced, ensuring the consistency and high quality of the products. At the same time, the introduction of multi-temperature segment control technology enables the sintering process to accurately match various complex process requirements, providing strong technical support for the production of high-end ceramic products.

[0040] The design of two independent external circulation lines not only improves the efficiency and flexibility of material transmission, but also realizes the parallel of production and maintenance. The first and second external circulation lines are responsible for the material circulation of two sets of running rails respectively, forming two closed-loop systems that do not interfere with each other. This design not only facilitates the loading and unloading of products during the day, but also provides convenience for monitoring the operating status of equipment during the night shift, effectively reducing the intensity of workers' night work and improving the safety and sustainability of overall production.

[0041] By reducing the amount of insulation material used on the outside of the furnace body and combining it with an efficient waste heat recovery mechanism, the four-hole co-directional high-temperature electric tunnel kiln has achieved a significant improvement in energy efficiency. Each kiln hole is relatively independent but interrelated, so that targeted maintenance or technical upgrades can be carried out on specific areas without affecting overall production. In addition, the modular design concept makes the equipment more flexible in future expansion or transformation, leaving room for the long-term development of the company.

[0042] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A high temperature electric tunnel kiln, characterized in that: Including furnace body and external circulation line; A plurality of kiln holes are provided in the furnace body, and running guide rails are installed in the plurality of kiln holes. The running directions of the plurality of running guide rails are the same. The two ends of the external circulation line are respectively connected to the two ends of the running guide rails. A plurality of temperature control zones are provided in the kiln holes, and the temperature control zones of the plurality of kiln holes completely overlap.

2. A high temperature electric tunnel kiln according to claim 1, characterized in that: The temperature control zones in the kiln hole are set to 6 to 8, the temperature of each temperature control zone is different, and the working current in the temperature control zone is 120 to 140A.

3. A high temperature electric tunnel kiln according to claim 1, characterized in that: The temperature field uniformity of the effective cross section of the furnace body is ±2°C.

4. A high temperature electric tunnel kiln according to claim 1, characterized in that: The temperature control zone is heated by a heating rod, and the heating rod is a silicon-molybdenum rod.

5. A high temperature electric tunnel kiln according to claim 1, characterized in that: The outer circulation line is provided with a circulation track, and the circulation track is connected to the running guide rail.

6. A high temperature electric tunnel kiln according to claim 1, characterized in that: A heat-insulating layer is arranged on the outer side of the furnace body.

7. A high temperature electric tunnel kiln according to claim 1, characterized in that: Two kiln holes are provided in the furnace body, and running guide rails are installed in the two kiln holes. The kiln is provided with an external circulation line, and two ends of the two running guide rails are respectively connected to two ends of the external circulation line.

8. The high temperature electric tunnel kiln according to claim 1, characterized in that: Four kiln holes are opened in the furnace body, and running guide rails are installed in the four kiln holes. The kiln is provided with two external circulation lines.

9. A high temperature electric tunnel kiln according to claim 8, characterized in that: The kiln is provided with a first external circulation line and a second external circulation line, wherein two ends of the first external circulation line are respectively connected to two ends of two running guide rails, and two ends of the second external circulation line are respectively connected to two ends of another two running guide rails.

10. A method for operating the high temperature electric tunnel kiln according to any one of claims 1 to 9, characterized in that: include: Start the kiln, the running rails and the external circulation line start to operate, place the ceramic body on the running rails, and the running rails deliver the ceramic body into the kiln hole steadily and accurately; The ceramic body passes through the temperature control zone in sequence to preheat and fire the ceramic body; After firing, the ceramic products are transported to the external circulation line, and after cooling, the ceramic products are centrally loaded and unloaded.

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