Method for solving product degreasing cracks or piebaldness through optimal design of tunnel kiln rubber discharging area

Abstract

The invention relates to the technical field of high-temperature kilns, in particular to a method for solving product degreasing cracks or piebaldness through optimal design of a tunnel kiln rubber discharging area, and an air inlet pipe used for conveying compressed air into a kiln to supplement oxygen is additionally arranged on a refractory material of the kiln rubber discharging area; the waste heat of the middle section of the kiln is utilized, three sections of main pipelines which are distributed up and down are pre-buried, and the upper preheating pipe, the middle preheating pipe and the lower preheating pipe are arranged in a staggered mode to supplement compressed air to three glue discharging temperature areas respectively. And a flow meter for controlling the amount of the required compressed air is additionally arranged on the preheating pipe of the three-section main pipeline. According to the invention, the gas inlet pipeline is additionally arranged on the refractory material of the kiln, and compressed air is introduced to supplement oxygen required by the rubber discharging area; compressed air is preheated through waste heat of the middle section of the kiln, and a preheating pipe main pipeline is arranged to control the temperature of the compressed air; the flow meter is additionally arranged on the preheating pipe, the supply amount of compressed air is accurately controlled, the rubber discharging speed is adjusted according to actual requirements, it is ensured that products are evenly heated in the degreasing process, and therefore cracks and mottles are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of high-temperature kilns, and in particular to a method for optimizing the design of a debonding zone of a tunnel kiln to solve degreasing cracks or mottling of products. Background Art

[0002] The existing air tunnel electric heating kiln is mainly used for sintering ceramic products, and its debinding area design has some obvious deficiencies. The current process directly uses heating elements for auxiliary heating, and naturally replenishes the air required for debinding through the gap between the kiln mouth and the product and the chimney suction. However, this method makes the air replenishment amount uncontrollable, and cannot fully guarantee the amount of oxygen required by the product during the debinding process, affecting the debinding effect. The two key conditions of the debinding process are the stability of the temperature curve and the adequacy of the oxygen supply. When the amount of oxygen in the air is insufficient, the debinding process of the product will be delayed, and the debinding cannot be completed as expected. Especially in the stage of rising temperature curve, the lack of oxygen will cause instantaneous debinding, and in severe cases, it may cause debinding cracks in the product; even if the situation is mild, it will produce spots due to incomplete carbonization, affecting product quality and consistency.

[0003] In addition, the Chinese patent CN203375838U discloses a dry-pressed electronic ceramic firing kiln, in which the distance between the heating rod and the sintered product is relatively close, and the opening size of the debinding area limits the air flow path. This design leads to uneven air flow in the debinding area, further exacerbating the problem of unsatisfactory debinding effect. Due to insufficient air circulation and temperature control in the kiln during the debinding process, especially when there is insufficient oxygen at medium and low temperature stages, the consistency and stability of the product during the degreasing process cannot be guaranteed, which easily leads to quality defects and unqualified rates.

[0004] Therefore, those skilled in the art provide a method for optimizing the design of a tunnel kiln debinding zone to solve degreasing cracking or mottling of products, so as to solve the problems raised in the above-mentioned background technology. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for optimizing the design of the debinding area of ​​a tunnel kiln to solve the degreasing cracking or mottling of products, which is specifically:

[0006] Install multiple air inlet pipes on the refractory material in the debonding area of ​​the kiln to deliver compressed air to the furnace to supplement oxygen;

[0007] Utilizing the waste heat in the middle section of the kiln, three sections of main pipelines distributed up and down are pre-buried as preheating pipes. The upper, middle and lower preheating pipes are staggered to supplement compressed air to the three temperature zones of the debinding process respectively.

[0008] A flow meter for controlling the required amount of compressed air is installed on the preheating pipe of the three-section main pipeline.

[0009] Preferably: the air inlet pipe adopts a decompression structure, with an external inlet diameter of 8 mm and an outlet diameter of 15 mm in the furnace.

[0010] Preferably: the air inlet pipe is composed of two sections of copper pipes, a copper pipe with an outer diameter of 8mm is used at the kiln insulation brick position, and a conical copper pipe with an outer diameter of 8mm at one end and a diameter of 15mm at one end inside the furnace is used at the kiln side brick position, and the end with an outer diameter of 8mm is connected to a section of copper pipe inside the insulation brick.

[0011] Preferably: the preheating tube has a diameter of 25 mm, a length of 6 m, and is made of 316 stainless steel.

[0012] Preferably: the temperature of the compressed air in the preheating tube is controlled at 100-200°C, and 6 drawer-type plug bricks are reserved for each of the three preheating tubes.

[0013] Preferably, the temperature of the debinding zone is controlled between 600-800°C.

[0014] Preferably, the debinding time is controlled between 1 and 2 hours.

[0015] Preferably, the oxygen content in the debinding atmosphere is controlled between 1% and 5%.

[0016] Preferably, an auxiliary agent is used during the debinding process, and the auxiliary agent includes a degreasing agent and an antioxidant, and specifically, stearic acid and paraffin can be used.

[0017] Preferably, after the debinding is completed, the cooling rate of the product is controlled between 1-5°C / min.

[0018] Compared with the prior art, the technical effects and advantages of the present invention are as follows:

[0019] 1. The present invention can effectively supplement the oxygen required in the debinding area by adding an air intake pipe to the kiln refractory material and adopting a decompression structure, thereby avoiding local oxygen deficiency, thereby reducing the occurrence of degreasing cracks and spots, and improving the integrity of debinding;

[0020] 2. The present invention uses the waste heat in the middle section of the kiln to preheat the compressed air, so that the compressed air is preheated before entering the debinding area, which helps to improve the temperature stability of the debinding area and promote the uniform degreasing of the products. The preheating pipe main pipeline is set, and the compressed air temperature is controlled. The drawer-type bricks are pre-buried to perform precise temperature control to ensure that the compressed air temperature in different debinding temperature zones is appropriate, improve the debinding efficiency, and reduce energy consumption;

[0021] 3. The present invention can accurately control the supply of compressed air by installing a flow meter on the preheating tube, and adjust the debinding speed according to actual needs, thereby ensuring that the product is evenly heated during the degreasing process, effectively reducing the formation of cracks and spots, and improving product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 The structure of the present invention is schematically shown in FIG. Figure 1 ;

[0023] Figure 2 The structure of the present invention is schematically shown in FIG. Figure 2 ;

[0024] Figure 3 The structure of the present invention is schematically shown in FIG. Figure 3 ;

[0025] Figure 4 The present invention Figure 1 Schematic diagram of the structure at A in the middle.

[0026] In the figure: 1. Kiln; 2. Air inlet pipe; 3. Preheating pipe; 4. Brick plugging. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described in order to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0028] Example 1

[0029] See also Figure 1 to Figure 4 In this embodiment, a tunnel kiln furnace debinding area optimization design method is provided to solve the degreasing cracking or spotting of products. The specific method is:

[0030] A plurality of air inlet pipes 2 are installed on the side wall of the kiln 1, that is, on the refractory material of the kiln 1 debonding area. The air inlet pipes 2 can transport external compressed air into the kiln 1, thereby replenishing the amount of oxygen required in the debonding area of ​​the kiln 1. The air inlet pipes 2 adopt a decompression structure, with an external inlet diameter of 8 mm and an outlet diameter of 15 mm (such as Figure 1 , Figure 4 As shown), this structural design helps to balance the internal pressure of the kiln 1, evenly introduce compressed air, and avoid incomplete debinding due to local oxygen deficiency;

[0031] Specifically, the pipeline of the air intake pipe 2 is composed of two sections of copper pipes. A copper pipe with an outer diameter of 8mm is used at the position of the insulation brick of the kiln 1, and a tapered hole with an outer diameter of 8-15mm and a gradually increasing diameter from the outside to the inside is opened at the position of the brick inside the kiln 1, which is used to place the other section of the copper pipe of the air intake pipe 2, that is, it is a tapered copper pipe with an outer diameter of 8mm at one end and a diameter of 15mm at the other end in the furnace. The end with an outer diameter of 8mm just docks with a section of the copper pipe in the insulation brick to form a complete air intake pipe 2;

[0032] At the same time, using the waste heat of the middle section of the kiln 1, three sections of 316 stainless steel main pipelines with a diameter of 25mm are pre-buried, namely the preheating pipes 3. The upper, middle and lower three preheating pipes 3 are staggered to preheat the compressed air. The length of the preheating pipe 3 is 6m. The temperature of the compressed air is controlled at 100-200℃. Six drawer-type plug bricks 4 are reserved for the three preheating pipes 3 for temperature control. Compressed air is supplemented to the three temperature zones of the debinding process respectively, which improves the debinding efficiency and reduces energy consumption by more than 3%.

[0033] A flow meter is installed on the preheating pipe 3 of the three-section main pipeline to control the required amount of compressed air, which helps to adjust the debinding speed according to actual needs and ensure that the product is evenly heated during the degreasing process, thereby reducing the formation of cracks and spots.

[0034] In addition to the above optimized design of the debinding area, the quality and yield of the fired products can also be improved through the following operations:

[0035] Adjust the debinding temperature: control the temperature of the debinding area within a suitable range to avoid excessively high temperatures that lead to too rapid degreasing of the product, thereby reducing the formation of cracks and spots. The temperature of the debinding area should be controlled between 600-800℃;

[0036] Optimize the debinding time: appropriately extend the debinding time to fully decompose and discharge the organic matter in the product, and reduce the stress effect of the residual organic matter on the product. The debinding time should be controlled between 1-2 hours;

[0037] Control the debinding atmosphere: During the debinding process, control the oxygen content in the atmosphere to avoid excessive oxygen content leading to surface oxidation of the product, thereby reducing the formation of cracks and spots. The oxygen content in the debinding atmosphere should be controlled between 1-5%;

[0038] Use of additives: During the debinding process, using appropriate additives, such as degreasing agents, antioxidants, etc., can help reduce the formation of cracks and spots. Commonly used additives include stearic acid, paraffin, etc.;

[0039] Optimize product structure: Optimize the structural design of the product to reduce internal stress concentration, thereby reducing the formation of cracks and spots. Appropriate ribs can be set inside the product to disperse internal stress.

[0040] Control the cooling rate: After debinding is completed, control the cooling rate of the product to avoid excessive cooling that causes internal stress concentration, thereby reducing the formation of cracks and spots. The cooling rate should be controlled between 1-5℃ / minute.

[0041] In the present invention, by installing an air inlet pipe 2 on the refractory material of the kiln 1, the oxygen required in the binder removal area can be supplemented by introducing compressed air, and the pipe adopts a decompression structure, which helps to balance the internal pressure of the kiln 1 and evenly introduce compressed air to avoid incomplete binder removal due to local oxygen deficiency;

[0042] At the same time, the waste heat in the middle section of the kiln 1 is used to preheat the compressed air, a preheating pipe 3 main pipeline is set, and the compressed air temperature is controlled. Drawer-type bricks are pre-buried to perform precise temperature control to ensure that the compressed air temperature in different debinding temperature zones is appropriate, improve debinding efficiency, and reduce energy consumption;

[0043] A flow meter is also installed on the preheating pipe 3 to accurately control the supply of compressed air. The debinding speed can be adjusted according to actual needs to ensure that the product is evenly heated during the degreasing process, thereby reducing the formation of cracks and spots.

[0044] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A method for optimizing the design of the debinding area of ​​a tunnel kiln to solve the problem of degreasing cracks or spots on products, characterized in that: The specific method is as follows: A plurality of air inlet pipes (2) for conveying compressed air into the furnace to supplement oxygen are installed on the refractory material in the binder removal area of ​​the kiln (1); Utilizing the waste heat of the middle section of the kiln (1), three sections of main pipelines distributed up and down are pre-buried as preheating pipes (3), and the upper, middle and lower preheating pipes (3) are staggered to respectively supplement compressed air to the three temperature zones of debinding; A flow meter for controlling the required amount of compressed air is installed on the preheating pipe (3) of the three-section main pipeline.

2. The method for optimizing the debinding area of ​​a tunnel kiln according to claim 1 to solve the degreasing cracking or mottling of products is characterized in that: The air inlet pipe (2) adopts a pressure reducing structure, with an external inlet diameter of 8 mm and an outlet diameter of 15 mm in the furnace.

3. The method for optimizing the debinding area of ​​a tunnel kiln according to claim 2 to solve the degreasing cracking or mottling of products is characterized in that: The air inlet pipe (2) is composed of two sections of copper pipes. The copper pipe with an outer diameter of 8 mm is located at the position of the insulation brick of the kiln (1). The side brick position of the kiln (1) is a conical copper pipe with an outer diameter of 8 mm at one end and a diameter of 15 mm at one end inside the furnace. The end with an outer diameter of 8 mm is connected to a section of copper pipe inside the insulation brick.

4. The method for optimizing the debinding area of ​​a tunnel kiln according to claim 1 to solve the degreasing cracking or mottling of products is characterized in that: The preheating tube (3) has a diameter of 25 mm, a length of 6 m, and is made of 316 stainless steel.

5. The method for optimizing the debinding area of ​​a tunnel kiln according to claim 4 to solve the degreasing cracking or mottling of products is characterized in that: The temperature of the compressed air in the preheating tube (3) is controlled at 100-200°C, and six drawer-type plug bricks (4) are reserved for each of the three preheating tubes (3).

6. A method for optimizing the debinding area of ​​a tunnel kiln to solve degreasing cracks or spots in products according to any one of claims 1 to 5, characterized in that: The temperature of the debinding zone is controlled between 600-800°C.

7. A method for optimizing the debinding area of ​​a tunnel kiln to solve degreasing cracks or spots in products according to any one of claims 1 to 5, characterized in that: The debinding time is controlled between 1 and 2 hours.

8. A method for optimizing the debinding area of ​​a tunnel kiln to solve degreasing cracks or spots in products according to any one of claims 1 to 5, characterized in that: The oxygen content in the debinding atmosphere is controlled between 1% and 5%.

9. A method for optimizing the debinding area of ​​a tunnel kiln to solve degreasing cracks or spots in products according to any one of claims 1 to 5, characterized in that: The auxiliary agent used in the debinding process includes a degreasing agent and an antioxidant, and specifically, stearic acid and paraffin can be used.

10. A method for optimizing the debinding area of ​​a tunnel kiln to solve degreasing cracks or spots in products according to any one of claims 1 to 5, characterized in that: After the debinding is completed, the cooling rate of the product is controlled between 1-5°C / minute.

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