A roller kiln slow cooling belt heat exchange device

Abstract

This utility model discloses a heat exchange device for a slow cooling zone in a roller kiln, comprising a kiln body, a conveying roller, several heat exchange tubes, a main heat exchange tube, an exhaust hood, and a decorative panel. The decorative panel is located on the outside of the kiln body, with an insulation space between the decorative panel and the outer wall of the kiln body. The conveying roller is located inside the kiln body. The main heat exchange tube and the exhaust hood are located above the kiln body, with the main heat exchange tube connected to the exhaust hood. Several heat exchange tubes are located inside the kiln body, above the conveying roller. The air inlet end of the heat exchange tube passes through the outer wall of the kiln body and is located within the insulation space, while the air outlet end of the heat exchange tube is connected to the main heat exchange tube. By setting a decorative panel outside the kiln body, forming an insulation space between the decorative panel and the kiln body, and placing the air inlet end of the heat exchange tube within the insulation layer, combined with an adjustable air inlet structure, the device effectively isolates external ambient temperature fluctuations, achieving the technical effects of improving the cooling uniformity of ceramic tile products and reducing thermal stress defects.

Description

Technical Field

[0001] This utility model relates to the field of roller kiln technology, and in particular to a heat exchange device for the slow cooling zone of a roller kiln. Background Technology

[0002] In the field of building ceramics production, the temperature control of the slow cooling zone of the roller kiln has a decisive impact on the quality of the finished ceramic tiles. Currently, the commonly used heat exchange solution in the industry is to extend the heat exchange tubes directly outside the roller kiln and indirectly cool the high-temperature products inside the kiln by drawing in ambient air (usually at a temperature of 30℃–40℃) from the outside environment.

[0003] However, this existing technology has significant drawbacks: 1. Excessive cooling temperature difference: Because the ambient air temperature is much lower than the ideal cooling range of the slow cooling zone (usually needs to be maintained at a gradient of 450℃–600℃), a sharp temperature difference is formed between the cold air and the products inside the kiln.

[0004] 2. Uncontrolled cooling rate: Excessive temperature difference causes violent forced convection in the heat exchange process, resulting in the actual cooling rate of the slow cooling zone far exceeding the process requirements (usually it needs to be controlled at ≤50℃ / min).

[0005] 3. Frequent product defects: Rapid cooling will create a steep thermal stress gradient inside the tile. When the stress exceeds the tensile strength limit of the material, it will induce micro-cracks (commonly known as "cooling cracks"), resulting in a decrease in the product quality rate and an increase in raw material loss.

[0006] At its root, the design logic of existing technologies focuses excessively on improving heat exchange efficiency, while neglecting the fact that the core of slow cooling processes lies in the smooth transition of the temperature field. Although some improvements attempt to alleviate the cooling rate by adjusting the airflow, the system can never stably maintain a slow cooling transition because the temperature of the cold air source itself is strongly correlated with the environment, and the fundamental problem remains unsolved. Utility Model Content

[0007] In response to the problems raised in the background art, the purpose of this utility model is to propose a heat exchange device for the slow cooling zone of a roller kiln, which solves the problem that the heat exchange structure of the existing slow cooling zone of the roller kiln draws ambient cold air and does not meet the requirements of slow cooling section.

[0008] To achieve this objective, the present invention adopts the following technical solution: A heat exchange device for a slow cooling zone of a roller kiln includes a kiln body, a conveying roller, several heat exchange tubes, a main heat exchange tube, an exhaust hood, and a decorative panel. The decorative panel is located on the outside of the kiln body, and there is an insulation space between the decorative panel and the outer wall of the kiln body. The conveying roller is located inside the kiln body. The main heat exchange tube and the exhaust hood are located above the kiln body, and the main heat exchange tube is connected to the exhaust hood. Several heat exchange tubes are disposed inside the kiln body and above the conveying roller. The air inlet end of the heat exchange tube passes through the outer wall of the kiln body and is located in the heat preservation space. The air outlet end of the heat exchange tube is connected to the heat exchange main tube.

[0009] Preferably, the heat exchange tube is provided with an adjusting sleeve, which is fitted onto the air inlet end and is used to adjust the air intake volume at the air inlet end.

[0010] Preferably, the adjusting sleeve includes a sleeve and an end sealing plate; The end sealing plate blocks one end opening of the sleeve. The side wall of the sleeve is symmetrically provided with two triangular through holes. The height of the triangular through holes is parallel to the axis of the sleeve, and the bottom of the triangular through holes is close to the end sealing plate.

[0011] Preferably, the decorative panel is provided with an adjustment hole, the position of which corresponds to the position of the adjustment sleeve; The decorative panel is detachably provided with a movable baffle, which is used to block the adjustment hole.

[0012] Preferably, the movable baffle includes a baffle and a mounting component, and the baffle is connected to the decorative panel via the mounting component.

[0013] Preferably, there are two mounting components, which are symmetrically mounted on both sides of the baffle. The decorative panel is provided with two grooves, and the two mounting components are slidably disposed in the two grooves respectively.

[0014] Preferably, the mounting component is a threaded connector.

[0015] Preferably, the baffle is a steel plate.

[0016] Compared with the prior art, one of the above technical solutions has the following beneficial effects: By setting a decorative panel on the outside of the kiln body, forming an insulation space between the decorative panel and the kiln body, and placing the air inlet of the heat exchange tube inside the insulation layer, combined with an adjustable air inlet structure, the external ambient temperature fluctuations are effectively isolated, which has the technical effect of improving the cooling uniformity of ceramic tile products and reducing thermal stress defects. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the slow cooling belt of a roller kiln according to an embodiment of the present invention; Figure 2 This is a front view of a heat exchange device according to an embodiment of the present invention; Figure 3This is a side view of a heat exchange device according to an embodiment of the present invention; Figure 4 yes Figure 3 Sectional view of AA; Figure 5 yes Figure 4 Enlarged view of point C in the middle; Figure 6a This is a schematic diagram of the state when the movable stop blocks the adjustment hole in one embodiment of the present invention; Figure 6b This is a schematic diagram showing the state of the movable stop when the adjustment hole is opened in one embodiment of this utility model; Figure 7 This is a schematic diagram of the structure of the adjusting sleeve according to an embodiment of the present invention; Figure 8 yes Figure 7 A cross-sectional view of BB.

[0018] The components include: heat exchange tube 1, air inlet 11, air outlet 12, heat exchange main tube 2, exhaust hood 3, decorative panel 4, adjustment hole 41, slide 42, movable baffle 5, baffle 51, mounting piece 52, adjustment sleeve 6, sleeve 61, triangular through hole 611, end sealing plate 62, conveying roller 8, kiln body 9, and insulation space 90. Detailed Implementation

[0019] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0020] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0021] Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first," "second," and "third" may explicitly or implicitly include one or more of that feature.

[0022] It should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0023] The following is in conjunction with the appendix Figures 1 to 8 The technical solution of this utility model will be further illustrated through specific implementation methods.

[0024] A heat exchange device for a slow cooling zone of a roller kiln includes a kiln body 9, a conveying roller 8, several heat exchange tubes 1, a heat exchange main pipe 2, an exhaust hood 3, and a decorative panel 4. The decorative panel 4 is located on the outside of the kiln body 9, and there is an insulation space 90 between the decorative panel 4 and the outer wall of the kiln body 9. The conveying roller 8 is located inside the kiln body 9. The heat exchange main pipe 2 and the exhaust hood 3 are located above the kiln body 9, and the heat exchange main pipe 2 is connected to the exhaust hood 3. Several heat exchange tubes 1 are disposed inside the kiln body 9 and above the conveying roller 8. The air inlet end 11 of the heat exchange tube 1 passes through the outer wall of the kiln body 9 and is located in the heat preservation space 90. The air outlet end 12 of the heat exchange tube 1 is connected to the heat exchange main tube 2.

[0025] By placing the air inlet 11 of the heat exchange tube 1 within the insulated space 90 formed by the decorative panel 4 and the outer wall of the kiln body 9, the air in this space is preheated using radiant heat from the outer wall of the kiln body and residual heat from within. Compared to the traditional method of directly extracting cold air from the external environment (30-40℃), the air temperature within the insulated space 90 can be raised to near the gradient required for a slow cooling zone, significantly reducing the initial temperature difference between the heat exchange medium (air) and the product, thus alleviating the problem of rapid heat exchange at its source. The temperature difference between the preheated air and the product within the kiln body 9 is significantly reduced, suppressing the formation of violent forced convection and stabilizing the actual cooling rate within the process requirement range of ≤50℃ / min. Through optimization of the temperature field gradient design, a smooth transition from high to low temperature is achieved, avoiding sudden changes in thermal stress caused by uncontrolled cooling rate. The gentle cooling process effectively reduces the steepening of the internal thermal stress gradient of the product (tile), and when the stress value is lower than the tensile strength limit of the material, the probability of microcracks (cooling cracks) is significantly reduced. This not only improves the product yield but also reduces raw material waste caused by cracks, meeting the industry's demand for energy conservation and emission reduction. Furthermore, compared to drawing in cold, low-temperature air from the external environment, the preheated air drawn from the insulated space 90, after internal heat exchange, has its temperature increased from below 200℃ to maintained at 250℃-300℃. This increased temperature allows the hot air to be utilized in the drying kiln, improving drying efficiency and facilitating heat recovery and utilization.

[0026] Traditional cold air source solutions are greatly affected by external environmental temperature fluctuations (such as seasonal changes and diurnal variations). This solution, however, utilizes the kiln's own waste heat to create a stable, insulated 90°C preheating environment, freeing the heat exchanger's temperature control from external environmental factors. This fundamentally improves system stability and process repeatability. This invention, through its cold air source preheating design, achieves control of the temperature field in the slow cooling zone. While improving heat exchange efficiency, it solves the problems of uncontrolled cooling rates and product defects caused by excessive temperature differences in traditional technologies, providing a more reliable thermal control solution for architectural ceramics production.

[0027] Furthermore, the heat exchange tube 1 is provided with an adjusting sleeve 6, which is fitted onto the air inlet end 11 and is used to adjust the air intake volume of the air inlet end 11.

[0028] The adjusting sleeve 6 is a movable structure fitted onto the outside of the air inlet end 11. By changing the axial displacement of the sleeve 61 relative to the air inlet end 11, the effective cross-sectional area of ​​the air inlet channel can be adjusted. The displacement of the adjusting sleeve 6 allows for rapid adjustment of the airflow, compensating for the impact of temperature differences on heat transfer intensity. For example, when an increase in ambient temperature leads to an increase in the temperature of the cold air, the air inlet area can be increased to enhance the airflow, maintaining the process requirements for the cooling rate and thus reducing internal crack defects in the product caused by uncontrolled cooling rates.

[0029] Furthermore, the adjusting sleeve 6 includes a sleeve 61 and an end sealing plate 62; The end sealing plate 62 blocks one end opening of the sleeve 61. The side wall of the sleeve 61 is symmetrically provided with two triangular through holes 611. The height of the triangular through holes 611 is parallel to the axis of the sleeve 61, and the bottom of the triangular through holes 611 is close to the end sealing plate 62.

[0030] The sleeve 61 is a hollow cylindrical structure, its shape adapted to the heat exchange tube 1. It can be fabricated using stainless steel tubing. Triangular through-holes 611 are formed on the side wall of the sleeve 61 to create an air inlet channel. The relative position of the triangular through-holes 611 and the air inlet end 11 is changed by adjusting the position of the sleeve 61 relative to the heat exchange tube 1, thus achieving continuous adjustment of the air inlet cross-sectional area. The height of the triangular through-holes 611 is parallel to the axis of the sleeve 61, causing the exposed area of ​​the triangular through-holes 611 to change non-linearly when the sleeve 61 is rotated, forming a gradual adjustment gradient. The two symmetrically arranged triangular through-holes 611 refer to a hole structure distributed with the sleeve axis as the center of symmetry. This symmetrical hole structure ensures uniform airflow distribution around the circumference of the sleeve 61, eliminating pressure imbalance caused by unilateral air inlet. The end-sealing plate 62 is a plate-shaped component that seals the end face of the sleeve 61, and can be fixedly connected to the sleeve 61 by welding. The end sealing plate 62 blocks the airflow channel at the end of the sleeve, forcing the airflow to enter the heat exchange tube 1 only through the triangular through hole 611 on the side wall.

[0031] To further explain, adjusting the sleeve 61 along the axis of the heat exchange tube 1 changes the relative position of the triangular through-hole 611 and the air inlet end 11 of the heat exchange tube. Since the height of the triangular through-hole 611 is parallel to the axis of the sleeve 61, the exposed area of ​​the triangular through-hole 611 changes non-linearly with the moving distance of the sleeve 61: assuming that in the initial stage, the apex of the triangular through-hole 611 is close to the air inlet end 11 of the heat exchange tube, the effective air inlet area of ​​the sleeve 61 is the largest, which is the area of ​​the entire triangular through-hole 611; as the sleeve 61 moves towards the kiln body 9, the exposed area of ​​the triangular through-hole 611 gradually decreases, and the bottom of the triangular through-hole 611 gradually approaches the air inlet end 11 of the heat exchange tube, and the effective air inlet area gradually decreases; when the end sealing plate 62 approaches the air inlet end 11, it is equivalent to the air inlet end 11 being blocked by the end sealing plate 62, and the heat exchange tube 1 cannot receive air.

[0032] Furthermore, the decorative panel 4 is provided with an adjustment hole 41, the position of which corresponds to the position of the adjustment sleeve 6; The decorative panel 4 is detachably provided with a movable baffle 5, which is used to block the adjustment hole 41.

[0033] The adjustment hole 41 is a through-hole structure formed on the decorative panel 4, which can be circular or rectangular. Its position corresponds to that of the adjustment sleeve 6, forming a window for adjusting the adjustment sleeve 6 located within the insulation space 90. The movable baffle 5 refers to the plate-like component covering the outside of the adjustment hole 41, which can be made of steel plate or high-temperature resistant alloy plate. It opens or closes the adjustment hole 41 through translation or rotation. Specifically, the movable baffle 5 normally blocks the adjustment hole 41 to prevent cold air from entering the insulation space 90 through the adjustment hole 41. When adjustment of the adjustment sleeve 6 is required, the adjustment hole 41 is opened through the movable baffle 5, allowing technicians to adjust the adjustment sleeve 6 located within the insulation space 90 from outside the equipment.

[0034] Furthermore, the movable baffle 5 includes a baffle 51 and a mounting component 52, wherein the baffle 51 is connected to the decorative panel 4 via the mounting component 52.

[0035] The baffle 51 is mechanically connected to the decorative panel 4 via the mounting member 52. The baffle 51 can be made of steel plate to withstand thermal stress under high-temperature conditions. The mounting member 52 can be a threaded connector, establishing a detachable connection through thread engagement.

[0036] Furthermore, there are two mounting members 52, which are symmetrically mounted on both sides of the baffle 51. The decorative panel 4 is provided with two sliding grooves 42, and the two mounting parts 52 are respectively slidably disposed in the two sliding grooves 42.

[0037] When the mounting components 52 are symmetrically distributed on both sides of the baffle 51, they form a symmetrical constraint structure, generating a balanced constraint force during the movement of the baffle 51, preventing tilting or displacement caused by unilateral force. The slide groove 42 and the mounting components 52 form a sliding pair. When the mounting components 52 move along the extension path of the slide groove 42, the baffle 51 remains parallel to the plane of the decorative panel 4. When an external force is applied to the baffle 51, the mounting components 52 on both sides move synchronously within the slide groove 42. Through the contact constraint of the groove wall on the mounting components 52, the degree of freedom of the baffle 51 in the direction perpendicular to the movement direction is eliminated.

[0038] Furthermore, the mounting component 52 is a threaded connector.

[0039] Threaded fasteners are fastening components with threaded structures, specifically bolts or screws, which generate axial preload through rotational movement. Lockable connections utilize the self-locking frictional properties of the threaded pair to achieve fixation; specifically, tightening the threaded fastener creates a rigid connection between the baffle and the decorative panel.

[0040] Furthermore, the baffle 51 is made of steel plate.

[0041] Preferably, the steel plate can be a cold-rolled steel plate or a hot-rolled steel plate, and the thickness of the steel plate can be 2mm to 5mm.

[0042] The technical principles of this utility model have been described above with reference to specific embodiments. These descriptions are merely for explaining the principles of this utility model and should not be construed as limiting the scope of protection of this utility model in any way. Based on this explanation, those skilled in the art can readily conceive of other specific embodiments of this utility model without any inventive effort, and these embodiments will all fall within the scope of protection of this utility model.

Claims

1. A slow cooling belt heat exchange device of a roller kiln, comprising a kiln body, a conveying roller, a plurality of heat exchange pipes, a heat exchange main pipe, an exhaust hood and a decorative panel, characterized in that: The decorative panel is located on the outside of the kiln body, and there is a heat insulation space between the decorative panel and the outer wall of the kiln body. The conveying roller is located inside the kiln body, and the heat exchange main pipe and the exhaust hood are located above the kiln body. The heat exchange main pipe is connected to the exhaust hood. Several heat exchange tubes are disposed inside the kiln body and above the conveying roller. The air inlet end of the heat exchange tube passes through the outer wall of the kiln body and is located in the heat preservation space. The air outlet end of the heat exchange tube is connected to the heat exchange main tube.

2. The slow cooling belt heat exchanger of claim 1, wherein: The heat exchange tube is provided with an adjustment sleeve, which is fitted onto the air inlet end and is used to adjust the air intake volume at the air inlet end.

3. A slow cooling belt heat exchanger for a roller hearth furnace as defined in claim 2, characterized in that: The adjusting sleeve includes a sleeve and an end sealing plate; The end sealing plate blocks one end opening of the sleeve. The side wall of the sleeve is symmetrically provided with two triangular through holes. The height of the triangular through holes is parallel to the axis of the sleeve, and the bottom of the triangular through holes is close to the end sealing plate.

4. A slow cooling belt heat exchanger for a roller hearth furnace as defined in claim 3, characterized in that: The decorative panel is provided with adjustment holes, the positions of which correspond to the positions of the adjustment sleeves; The decorative panel is detachably provided with a movable baffle, which is used to block the adjustment hole.

5. A slow cooling belt heat exchanger for a roller kiln as claimed in claim 4, wherein: The movable baffle includes a baffle and a mounting component, and the baffle is connected to the decorative panel via the mounting component.

6. A slow cooling belt heat exchanger for a roller kiln as claimed in claim 5, wherein: The number of mounting components is two, and the two mounting components are symmetrically installed on both sides of the baffle; The decorative panel is provided with two grooves, and the two mounting components are slidably disposed in the two grooves respectively.

7. A slow cooling belt heat exchanger for a roller hearth furnace as defined in claim 6, characterized in that: The mounting component is a threaded connector.

8. A slow cooling belt heat exchanger for a roller kiln as claimed in claim 6, characterised in that: The baffle is made of steel plate.

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