Large tunnel furnace with uniform temperature rise

Abstract

The utility model discloses a large-scale tunnel furnace with uniform temperature rise, which comprises a bottom frame, a conveyor belt and a box body are arranged on the bottom frame, the interior of the box body is divided into heating areas, a hot air circulation device is arranged in each heating area, the hot air circulation device comprises a first fan arranged on the box body, the first fan is connected with an air outlet duct and an air inlet duct, and the air inlet duct is connected with an air outlet. A first heater is arranged in the air duct, the air outlet duct and the air inlet duct are located above and below the conveying belt respectively, and the draught fan enables hot air flow to flow out of the air outlet duct, flow through the conveying belt to heat materials and flow back to the air inlet duct. Hot air flows out from the upper portion of the conveying belt, flows back to the lower portion of the conveying belt and makes full contact with materials on the conveying belt, a closed hot air circulation is formed, and the materials are evenly and stably heated in the conveying process. And each heating area is provided with the independent first heater and the first fan, each heating area is independently controlled, and the temperature can be flexibly adjusted according to the baking requirements of the materials.

Description

Technical Field

[0001] The utility model relates to the technical field of tunnel furnaces, and more specifically to a large-scale tunnel furnace with uniform temperature rise. Background Art

[0002] Tunnel furnace is a tunnel-type mechanical equipment that completes material baking through heat conduction, convection and radiation. The furnace body is generally very long, with a minimum of 6 meters and a maximum length of 60 to 80 meters. The baking chamber is generally a narrow tunnel with a width of 80cm to 140cm. There is a continuously operating conveying system in the tunnel. When the material is baked, the material moves relative to the heat source through the conveying chain plate, steel belt or mesh belt, thereby completing the heating and conveying work. Tunnel furnace can produce continuously, with high production efficiency, labor saving and stable heating quality.

[0003] In some existing convection tunnel furnaces, the heat flow only flows through the upper surface or the lower surface of the material, and the contact angle with the material is large, resulting in insufficient contact between the heat flow and the material, making the heat convection efficiency low.

[0004] The above shortcomings need to be improved. Summary of the invention

[0005] In order to solve the problem that in some existing convection tunnel furnaces, the heat flow only flows through the upper surface or the lower surface of the material and the contact angle with the material is large, resulting in insufficient contact between the heat flow and the material and low heat convection efficiency, the utility model provides a large-scale tunnel furnace with uniform temperature rise.

[0006] The technical solution of the utility model is as follows:

[0007] A large-scale tunnel furnace with uniform temperature rise comprises a base frame, a conveyor belt and a box body are arranged on the base frame, two ends of the conveyor belt pass through two ends of the box body respectively, the interior of the box body is divided into a plurality of heating zones with independently controlled temperatures along the conveyor belt direction, a hot air flow circulation device is arranged in each of the heating zones, the hot air flow circulation device comprises a first fan arranged on the box body, an air outlet of the first fan is connected to an air outlet duct, an air inlet of the first fan is connected to an air inlet duct, a first heater for heating the air flow is arranged in the air outlet duct or the air inlet duct, the air outlet duct is located above the conveyor belt, and the air inlet duct is located below the conveyor belt, the fan causes the hot air flow to flow out from the air outlet duct, flow through the conveyor belt to heat the material on the conveyor belt, and then flow back to the air inlet duct.

[0008] Furthermore, side doors are provided at both ends of the box body, a feed port is provided on the side door at the feed end, and a discharge port is provided on the side door at the discharge end, and both ends of the conveyor belt pass through the box body from the feed port and the discharge port respectively.

[0009] Furthermore, inspection doors are provided on both sides of the box body, and a plurality of inspection doors are distributed at intervals on the side of the box body. A groove is provided on the inspection door, and a gripping portion is provided in the groove.

[0010] Furthermore, a heat insulation layer is provided on the inner wall of the box, and the thickness of the heat insulation layer is 100 mm to 200 mm.

[0011] Furthermore, a preheating device is provided on the outside of the box at one feeding end.

[0012] Furthermore, the preheating device includes a second fan, and a second heater is provided at an air outlet of the second fan.

[0013] Furthermore, the box body is provided with an air inlet pipe connected to the air inlet of the first fan, and an exhaust pipe connected to the inner cavity of the box body, and valves are provided on the air inlet pipe and the exhaust pipe.

[0014] Furthermore, the valve includes a slideway in which a valve plate is slidably arranged, the valve plate includes a vent portion and an air-closing portion, a plurality of vent holes are provided at the vent portion, and sliding the valve plate changes the overlapping area between the vent portion or the air-closing portion and the channel of the pipeline.

[0015] Furthermore, a first limiting portion and a second limiting portion are respectively provided at both ends of the valve plate. When the first limiting portion contacts the first end of the slide, the air-blocking portion completely overlaps with the channel of the pipeline. When the second limiting portion contacts the second end of the slide, the venting portion completely overlaps with the channel of the pipeline.

[0016] Furthermore, a power distribution cabinet electrically connected to the electrical equipment in the box is provided on one side of the box, and a controller for controlling the operation of the tunnel furnace is provided on the outside of the power distribution cabinet.

[0017] The utility model according to the above scheme has the beneficial effect that, in the utility model, the hot air flow flows out from the top of the conveyor belt, flows back to the bottom of the conveyor belt, fully contacts with the material on the conveyor belt, forms a closed hot air flow cycle, so that the material is evenly and stably heated during the conveying process; and each heating zone is equipped with an independent first heater and a first fan, each heating zone is independently controlled, and the temperature can be flexibly adjusted according to the baking requirements of the material, further improving the production efficiency, ensuring that the temperature of each heating zone is uniform, and preventing the problem of excessive temperature difference on the surface of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a structural schematic diagram of the utility model;

[0020] Figure 2 It is a schematic diagram of the longitudinal section structure of the box body in the utility model;

[0021] Figure 3 It is a schematic diagram of the cross-sectional structure of the box body in the utility model;

[0022] Figure 4 This is a schematic diagram of the three-dimensional structure of the box body in the utility model in the first direction;

[0023] Figure 5 It is a schematic diagram of the three-dimensional structure of the box body in the utility model in the second direction;

[0024] Figure 6 It is a structural schematic diagram of the valve in the utility model.

[0025] Among them, the figure marks in the figure are: 1. chassis; 2. conveyor belt; 3. box; 301. heating zone; 302. side door; 303. inspection door; 304. insulation layer; 305. air inlet pipe; 306. exhaust pipe; 4. hot air flow circulation device; 401. first fan; 402. air outlet duct; 403. air inlet duct; 404. first heater; 5. preheating device; 501. second fan; 502. second heater; 6. valve; 601. slide; 602. valve plate; 603. ventilation part; 604. air closing part; 605. air vent; 606. first limit part; 607. second limit part; 7. distribution cabinet; 701. controller. DETAILED DESCRIPTION

[0026] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] It should be noted that when a component is referred to as being "fixed" or "set" or "connected" to another component, it may be located directly or indirectly on the other component. The directions or positions indicated by the terms "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the directions or positions shown in the accompanying drawings and are only for the convenience of description and should not be construed as limitations on the present technical solution. The terms "first", "second", etc. are only used for the convenience of description and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features. "Multiple" means two or more, unless otherwise clearly and specifically defined. "Several" means one or more, unless otherwise clearly and specifically defined.

[0028] like Figures 1 to 5 As shown, a large-scale tunnel furnace with uniform temperature rise described in one embodiment of the utility model comprises a base frame 1, a conveyor belt 2 and a box body 3 are arranged on the base frame 1, two ends of the conveyor belt 2 pass through two ends of the box body 3 respectively, and the interior of the box body 3 is divided into a plurality of heating zones 301 with independently controlled temperatures along the conveyor belt 2. In this example, two heating zones 301 A and B are arranged, and each heating zone 301 is provided with a hot air circulation device 4, and the hot air circulation device 4 comprises a first heating zone 3 arranged on the box body 3. The fan 401, the air outlet of the first fan 401 is connected to the air outlet duct 402, the air inlet of the first fan 401 is connected to the air inlet duct 403, the air outlet duct 402 or the air inlet duct 403 is provided with a first heater 404 for heating the air flow, the air outlet duct 402 is located above the conveyor belt 2, and the air inlet duct 403 is located below the conveyor belt 2. The fan causes the hot air flow to flow out from the air outlet duct 402, flow through the conveyor belt 2 to heat the material on the conveyor belt 2, and flow back to the air inlet duct 403.

[0029] When the device is working, the power of the tunnel furnace is first turned on, and the first heater 404 of each heating zone 301 is turned on to preheat the air in the box 3. At the same time, the first fan 401 of each heating zone 301 also starts working to form a preliminary hot air flow circulation. After the preheating reaches the set temperature, the conveyor belt 2 is started, and the material to be baked is placed on the conveyor belt 2. Figure 1 The direction of the middle arrow is the material flow direction. The conveyor belt 2 brings the material into the box 3 from one end and gradually passes through each heating zone 301.

[0030] Figure 2 and Figure 3The direction of the middle arrow is the direction of air flow. In each heating zone 301, the first fan 401 sucks air from the box 3 through the air inlet duct 403, and then heats it through the first heater 404. The heated hot air flows out through the air outlet duct 402 and blows directly to the material on the conveyor belt 2 to heat it. The heated hot air continues to flow through the surface of the material, and then flows back to the air inlet duct 403 through the gap between the conveyor belt 2 and the material, forming a closed hot air flow cycle.

[0031] Each heating zone 301 is equipped with an independent first heater 404 and a first fan 401, so the temperature of each heating zone 301 can be independently controlled. According to the baking requirements and process requirements of the material, the temperature of each heating zone 301 can be flexibly adjusted to ensure that the material is evenly and stably heated in the tunnel furnace. After being baked in multiple heating zones 301, the material is sent out from the other end of the box 3. At this time, the material has achieved the desired baking effect and can be subsequently packaged or processed.

[0032] In this example, the hot air flow in the utility model flows out from the top of the conveyor belt 2, flows back to the bottom of the conveyor belt 2, and fully contacts the materials on the conveyor belt 2, forming a closed hot air flow cycle, so that the materials are evenly and stably heated during the conveying process; and each heating zone 301 is equipped with an independent first heater 404 and a first fan 401, and each heating zone 301 is independently controlled, and the temperature can be flexibly adjusted according to the baking requirements of the material, further improving the production efficiency, and ensuring that the temperature of each heating zone 301 is uniform. At the same time, the tunnel furnace adopts a continuous transmission method, which can be continuously produced, greatly improving the production efficiency.

[0033] In practical applications, through holes can be opened on the conveyor belt, or multiple spaced conveyor belts 2 can be set, so that the airflow can pass through the conveyor belt 2 more smoothly, and the material is exposed to a larger area on the conveyor belt 2, thereby increasing the heated area of ​​the material and further improving the heat convection efficiency. In addition, partitions can be set between each heating zone 301 to better control the temperature of each zone.

[0034] like Figure 4 As shown, in a preferred embodiment, side doors 302 are provided at both ends of the box body 3, a feed port is provided on the side door 302 at the feed end, and a discharge port is provided on the side door 302 at the discharge end, and both ends of the conveyor belt 2 pass through the box body 3 from the feed port and the discharge port respectively.

[0035] In this embodiment, the design of the side door 302 and the feed port and the discharge port makes the material entry and exit simple and fast, thereby improving production efficiency. After the side door 302 is closed, the sealing of the box body 3 can be ensured, so that the heat can be effectively circulated inside the box body 3, reducing heat loss and improving energy utilization efficiency. The design of the side door 302 allows the tunnel furnace to be easily expanded or adjusted when necessary, such as increasing or decreasing the heating zone 301, adjusting the speed of the conveyor belt 2, etc.

[0036] like Figure 4 As shown, in a preferred embodiment, inspection doors 303 are provided on both sides of the box body 3, and a plurality of inspection doors 303 are spaced apart on the sides of the box body 3, and a groove is provided on the inspection door 303, and a gripping portion is provided in the groove.

[0037] When it is necessary to maintain, overhaul or adjust the equipment or structure inside the tunnel furnace, the operator firmly holds the inspection door 303 through the gripping part and then gently pulls it outward. The design of the inspection door 303 makes it easy to open, and due to the gripping part, the operator can easily keep the door open for further operations. Through the observation window on the inspection door 303, the operator can intuitively view the situation inside the tunnel furnace, such as the operating status of the conveyor belt 2, the operation of the first fan 401, etc. It helps the operator to quickly and accurately judge the operating status of the equipment and whether further maintenance or adjustment is required. If a problem is found or maintenance operations are required, the operator can enter the interior of the box 3 through the opened inspection door 303 and perform necessary operations, such as replacing damaged parts, adjusting the tension of the conveyor belt 2, etc. After completing the maintenance and overhaul operations, the operator holds the gripping part of the inspection door 303 again and gently pushes the door back to its original position to ensure the sealing and integrity of the box 3.

[0038] like Figure 2 As shown, in a preferred embodiment, the inner wall of the box body 3 is provided with a heat insulation layer 304, and the thickness of the heat insulation layer 304 is 100 mm to 200 mm.

[0039] In this embodiment, the heat insulation layer 304 can reduce the amount of heat lost to the external environment through the inner wall of the box 3, thereby ensuring that more heat is used for baking the material, helping to maintain the temperature stability in the box 3 and improve the baking efficiency. Since the heat loss is reduced, the energy required by the tunnel furnace during the baking process will also be reduced accordingly, which can not only reduce production costs, but also help to achieve a green and sustainable production method. The heat insulation layer 304 can reduce the temperature of the outer wall of the box 3, reduce the impact on the working environment, make the working environment around the tunnel furnace more comfortable, and help improve the work efficiency of employees.

[0040] like Figure 2As shown, in a preferred embodiment, a preheating device 5 is provided at the feeding end of the outer side of the box body 3. The preheating device 5 comprises a second fan 501, and a second heater 502 is provided at the air outlet of the second fan 501.

[0041] In this embodiment, the preheating device 5 allows the material to obtain a certain initial temperature before entering the tunnel furnace. This means that the material needs to absorb less heat in the tunnel furnace, thereby shortening the baking time and improving the baking efficiency. Preheating can allow the material to be heated more evenly during the baking process. Because the material is already at a higher temperature since the preheating stage, it can reach the required temperature for baking more quickly and reduce the temperature gradient or temperature difference that may occur during the baking process. This helps to ensure that the material is baked evenly and improve product quality. By adjusting the power or temperature setting of the second heater 502, the output temperature of the preheating device 5 can be easily changed to meet the baking requirements of different materials.

[0042] like Figures 4 to 6 As shown, in a preferred embodiment, the box body 3 is provided with an air inlet pipe 305 connected to the air inlet of the first fan 401, and an exhaust pipe 306 connected to the inner cavity of the box body 3, and valves 6 are provided on the air inlet pipe 305 and the exhaust pipe 306.

[0043] The valve 6 includes a slide 601 in which a valve plate 602 is slidably arranged. The valve plate 602 includes a vent portion 603 and an air-blocking portion 604. The vent portion 603 is provided with a plurality of vent holes 605. The sliding valve plate 602 changes the overlapping area between the vent portion 603 or the air-blocking portion 604 and the channel of the pipeline.

[0044] The first limiting portion 606 and the second limiting portion 607 are respectively provided at both ends of the valve plate 602. When the first limiting portion 606 contacts the first end of the slide 601, the air-blocking portion 604 completely overlaps with the channel of the pipeline. When the second limiting portion 607 contacts the second end of the slide 601, the ventilation portion 603 completely overlaps with the channel of the pipeline.

[0045] When the present embodiment is working, when the valve 6 is in the initial state, the valve plate 602 may be located in the middle of the slideway 601. At this time, the venting portion 603 and the air-blocking portion 604 do not completely overlap with the pipeline channel, allowing a certain amount of airflow to pass through.

[0046] If the amount of airflow needs to be increased, the operator can slide the valve plate 602 to increase the overlap area between the vent portion 603 and the pipeline channel, so that more airflow enters or exits the box 3 through the vent hole 605. When the second stop portion 607 of the valve plate 602 contacts the second end of the slideway 601, the vent portion 603 completely overlaps with the pipeline channel, and the valve 6 is fully opened at this time, and airflow can pass freely.

[0047] If the amount of airflow needs to be reduced, the operator can slide the valve plate 602 to increase the overlap area between the air-blocking portion 604 and the pipeline channel, thereby reducing the amount of airflow. When the first stopper 606 of the valve plate 602 contacts the first end of the slideway 601, the air-blocking portion 604 completely overlaps with the pipeline channel, and the valve 6 is completely closed, so that airflow cannot pass through.

[0048] In this embodiment, the valve 6 allows the operator to flexibly adjust the amount of airflow as needed. Whether increasing or decreasing the airflow, it can be achieved by simply sliding the valve plate 602. By controlling the size of the vent hole 605 of the vent portion 603, the airflow passing through can be filtered.

[0049] like Figure 1 As shown, in a preferred embodiment, a power distribution cabinet 7 electrically connected to the electrical equipment in the box 3 is provided on one side of the box 3, and a controller 701 for controlling the operation of the tunnel furnace is provided on the outer side of the power distribution cabinet 7.

[0050] In this embodiment, the power distribution cabinet 7 provides a stable and safe power supply for the electrical equipment in the tunnel furnace, ensuring the continuity and stability of the tunnel furnace during the baking process. The controller 701 can ensure high-precision control of the baking process by real-time monitoring and adjusting the operating parameters of the tunnel furnace, thereby improving product quality and production efficiency. Through the controller 701, the operator can easily control the operation of the tunnel furnace, realize automated production, and reduce manual intervention.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A large tunnel furnace with uniform temperature rise, characterized in that: It comprises a bottom frame, on which a conveyor belt and a box body are arranged, and two ends of the conveyor belt pass through two ends of the box body respectively. The interior of the box is divided into a plurality of independently temperature-controlled heating zones along the conveyor belt direction, each of the heating zones is provided with a hot air circulation device, the hot air circulation device comprises a first fan provided on the box, the air outlet of the first fan is connected to an air outlet duct, the air inlet of the first fan is connected to an air inlet duct, the air outlet duct or the air inlet duct is provided with a first heater for heating the airflow, The air outlet duct is located above the conveyor belt, and the air inlet duct is located below the conveyor belt. The fan causes the hot air flow to flow out from the air outlet duct, flow through the conveyor belt to heat the material on the conveyor belt, and then flow back to the air inlet duct.

2. A large tunnel furnace with uniform temperature rise according to claim 1, characterized in that: Both ends of the box body are provided with side doors, the side door at the feeding end is provided with a feeding port, and the side door at the discharging end is provided with a discharging port, and both ends of the conveyor belt pass through the box body from the feeding port and the discharging port respectively.

3. According to the large-scale tunnel furnace with uniform temperature rise as described in claim 1, it is characterized in that: Inspection doors are arranged on both sides of the box body, and a plurality of inspection doors are distributed at intervals on the side of the box body. A groove is arranged on the inspection door, and a gripping portion is arranged in the groove.

4. A large tunnel furnace with uniform temperature rise according to claim 1, characterized in that: The inner wall of the box body is provided with a heat insulation layer, and the thickness of the heat insulation layer is 100mm to 200mm.

5. A large tunnel furnace with uniform temperature rise according to any one of claims 1 to 4, characterized in that: A preheating device is arranged on the outside of the box at one feeding end.

6. A large tunnel furnace with uniform temperature rise according to claim 5, characterized in that: The preheating device comprises a second fan, and a second heater is provided at the air outlet of the second fan.

7. A large tunnel furnace with uniform temperature rise according to any one of claims 1 to 4, characterized in that: The box body is provided with an air inlet pipe connected with the air inlet of the first fan, and an exhaust pipe connected with the inner cavity of the box body, and valves are provided on the air inlet pipe and the exhaust pipe.

8. A large tunnel furnace with uniform temperature rise according to claim 7, characterized in that: The valve comprises a slideway in which a valve plate is slidably arranged, the valve plate comprises a venting portion and an air-blocking portion, a plurality of vent holes are provided at the venting portion, and sliding the valve plate changes the overlapping area of ​​the venting portion or the air-blocking portion and the channel of the pipeline.

9. A large tunnel furnace with uniform temperature rise according to claim 8, characterized in that: The valve plate is provided with a first limiting portion and a second limiting portion at both ends respectively. When the first limiting portion contacts the first end of the slide, the air-blocking portion completely overlaps with the channel of the pipeline. When the second limiting portion contacts the second end of the slide, the venting portion completely overlaps with the channel of the pipeline.

10. A large tunnel furnace with uniform temperature rise according to any one of claims 1 to 4, characterized in that: A power distribution cabinet electrically connected to the electrical equipment in the box is arranged on one side of the box body, and a controller for controlling the operation of the tunnel furnace is arranged on the outer side of the power distribution cabinet.

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