Preheating device for spiral pipe of roller kiln

Abstract

The utility model discloses a preheating device for a spiral pipe of a roller kiln. The preheating device comprises a furnace body, a plurality of roller bars, an air distribution cavity arranged at the lower part of the furnace body and a plurality of air distribution pipes, the upper end of the air distribution pipe is positioned below the roller rod; at least one inner air inlet pipe is arranged at the inner bottom end of the air distribution cavity; a heating pipe is coaxially arranged in the inner gas inlet pipe; at least one ceramic ring is coaxially arranged on the outer wall of the heating pipe and abuts against the inner wall of the inner air inlet pipe. And two spiral grooves are symmetrically formed in the inner wall of the heating pipe and penetrate through the outside of the heating pipe. The preheating device preheats process gas entering the furnace body, the gas flows in the heating pipe and is heated, and the preheated process gas is transferred to a sintered product, so that the sintered product is more uniformly heated in the heating process, the uniformity of atmosphere in the furnace is effectively improved, the energy consumption in the heating process is reduced, and the quality of the sintered product is improved.

Description

Technical Field

[0001] This utility model belongs to the technical field of industrial atmosphere sintering roller kiln, and particularly relates to a roller kiln spiral tube preheating device. Background Technology

[0002] Roller kilns are high-temperature heating equipment widely used in industries such as ceramics, glass, and powder metallurgy. Their working principle primarily involves the flow of high-temperature gas generated by fuel combustion within the furnace, transferring heat to the surface of the workpiece to complete the heat treatment. Gas preheating is a crucial step in the roller kiln production process, directly impacting product quality and production efficiency. In existing technologies, when the products are being fired in the heating or isothermal sections of the roller kiln, process gas is directly injected into the furnace, causing excessive temperature differences within the furnace and affecting the quality of the fired products.

[0003] Chinese patent document CN116242134A discloses a roller kiln with side preheating air inlet, including a kiln body. The kiln body is provided with an air supply pipeline mechanism, which includes an air supply mechanism located outside the end of the kiln body, several air supply pipes located inside the kiln body, and an air inlet mechanism located outside the front of the kiln body. It can supply oxygen to the front section of the kiln body to meet the oxygen demand of the material reaction in the front section of the kiln body.

[0004] The aforementioned patented solution utilizes the waste heat of the kiln to preheat the process gas entering the kiln. While this can save energy, it suffers from the drawback of uncontrollable temperature. In particular, for products with high firing requirements, if the temperature of the process gas entering the kiln does not reach the preset value, or if the temperature of the process gas fluctuates, it will directly affect the quality of the fired products. Utility Model Content

[0005] To overcome the technical problem in existing technologies where process gases entering the roller kiln require preheating, and where utilizing waste heat from the kiln for gas preheating results in poor temperature control and fails to meet high-standard firing requirements, this invention aims to provide a spiral tube preheating device for roller kilns. This device involves setting up a gas distribution chamber at the bottom of the kiln body for uniformly supplying gas to the rollers, and simultaneously installing a heating tube within the gas distribution chamber for heating the gas. External process gas passes through the heating tube, is heated, and enters the gas distribution chamber through spiral grooves on the outer wall of the heating tube. Preheating temperature is accurately controlled via electric heating. Furthermore, the heating tube extends the preheating path and time of the process gas, ensuring temperature control while also helping to increase the input volume of process gas.

[0006] To achieve the above objectives, this utility model adopts the following technical solution: a preheating device for a roller kiln spiral tube, comprising a furnace body, multiple rollers arranged linearly and horizontally in the middle of the furnace body, a gas distribution chamber located in the lower part of the furnace body, and multiple evenly distributed gas distribution pipes located on the gas distribution chamber; the upper end of the gas distribution pipe is located below the rollers; at least one inner air inlet pipe is provided at the bottom of the gas distribution chamber; a heating tube is coaxially arranged inside the inner air inlet pipe; wherein, process gas is introduced through the inside of the heating tube; at least one ceramic ring is coaxially arranged on the outer wall of the heating tube, the ceramic ring abutting against the inner wall of the inner air inlet pipe; the ceramic ring serves as support and insulation; two spiral grooves are symmetrically arranged on the inner wall of the heating tube, the spiral grooves extending to the outside of the heating tube.

[0007] Furthermore, one end of the inner air inlet pipe is located in the middle of the air distribution chamber, and the other end is located on the outer wall of the furnace body; one end of the heating pipe is located in the middle of the inner air inlet pipe, and the other end extends out from the outer wall of the furnace body; an outer air inlet pipe is inserted into the end of the heating pipe that extends out of the furnace body.

[0008] The heating tube is placed inside the inner air inlet pipe, which effectively prevents the process gas from escaping; the tube structure also extends the heating path and heating time of the process gas, which facilitates temperature control and also helps to increase the air intake.

[0009] Furthermore, the outer wall of the furnace body is provided with at least one preheating box; the preheating box is provided with an interface pipe at one end away from the furnace body; wherein, the interface pipe is coaxially arranged with the external air inlet pipe, the inner diameter of the interface pipe is larger than the outer diameter of the external air inlet pipe, and the end of the external air inlet pipe is located in the middle of the interface pipe.

[0010] Process gas enters the heating tube through the interface pipe to prevent heat from escaping and improve heat conversion efficiency.

[0011] Specifically, the preheating box has terminals extending through its upper and lower ends; each terminal has a locking screw detachably connected to its upper and lower ends; and the two electrodes of the heating tube are respectively disposed on adjacent terminals.

[0012] The external air inlet pipe facilitates the entry of process gas from the interface pipe; the external air inlet pipe also prevents the positive and negative electrodes of the heating tube from coming into contact, thus providing insulation.

[0013] Furthermore, the gas distribution chamber is formed by refractory bricks; the lower end of the gas distribution pipe extends into the middle of the gas distribution chamber.

[0014] The process gas in the gas distribution chamber is evenly distributed to exchange heat, preventing process gas with uneven temperature from directly entering the gas distribution pipe, thereby making the gas temperature in each gas distribution pipe uniform.

[0015] Furthermore, the upper end of the air distribution pipe is aligned with the joint hole of the sagger on the roller; the joint hole is the contact position of two adjacent saggers, ensuring the oxidizing atmosphere requirement of the bottom middle sagger.

[0016] Preferably, the preheating box has an opening at the end away from the furnace body; the interface pipe has a sealing plate at the end facing the preheating box; the sealing plate is used to close the opening, and the sealing plate is detachably connected to the preheating box.

[0017] Depending on the process gas, the sealing plate can be replaced, which also facilitates the inspection and adjustment of the circuitry inside the preheating box.

[0018] Specifically, the outer wall of the furnace body is provided with at least one annular base; the inner wall of the base is provided with a chamfer at the end away from the furnace body; the inner air inlet pipe is provided with a flange at the end near the outer wall of the furnace body; the flange is detachably connected to the base.

[0019] Furthermore, one end of the heating tube extending out of the furnace body is wrapped with insulating cloth; the electrode is disposed between the insulating cloth and the outer wall of the heating tube; and a clamp is detachably connected to the outer periphery of the insulating cloth.

[0020] Specifically, the air distribution pipe, the inner air intake pipe, the outer air intake pipe, and the ceramic ring are made of ceramic.

[0021] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0022] 1. This preheating device preheats the process gas entering the furnace. The gas flows and is heated in the heating tube. The heating tube extends the heating path and heating time, which makes it easier to control the preheating temperature and also helps to increase the gas intake.

[0023] 2. The preheated process gas is transferred to the fired products, making them heat more evenly during the heating process. This effectively improves the uniformity of the atmosphere inside the furnace, reduces energy consumption during the heating process, and improves the quality of the fired products.

[0024] 3. The preheating device has a high degree of integration, a compact structure, and is easy to load and unload, thus making it easy to assemble and replace. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the assembly structure of this utility model;

[0026] Figure 2 This is a schematic diagram of the preheating device of this utility model;

[0027] Figure 3 The preheating box of this utility model ( Figure 1 A structural diagram of Part A.

[0028] In the diagram: 1. Furnace body; 11. Preheating box; 111. Interface pipe; 112. Sealing plate; 12. Chassis; 13. Flange; 21. Sagger; 22. Roller; 31. Gas distribution pipe; 32. Gas distribution chamber; 33. Inner air inlet pipe; 41. Heating tube; 411. Spiral groove; 42. Ceramic ring; 43. Outer air inlet pipe; 44. Insulating cloth; 45. Clamp; 46. Electrode; 5. Terminal; 51. Locking screw. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0030] In the description of this utility model, it should be noted that the directional terms such as "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" are 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. They should not be construed as limiting the specific protection scope of this utility model.

[0031] Furthermore, the terms "first" and "second" 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. Thus, the use of "first" and "second" to define a feature may explicitly or implicitly include one or more of that feature. In this description of the utility model, "a number" means two or more, unless otherwise explicitly specified.

[0032] In this utility model, unless otherwise explicitly specified and limited, terms such as "set" and "install" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can also refer to a mechanical connection; they can refer to a direct connection or a connection through an intermediate medium; or 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 according to the specific circumstances.

[0033] See Figures 1-3 A preheating device for a roller kiln spiral tube includes a furnace body 1, a plurality of rollers 22 arranged linearly and horizontally in the middle of the furnace body 1, a gas distribution chamber 32 disposed in the lower part of the furnace body 1, and a plurality of gas distribution pipes 31 evenly distributed longitudinally disposed on the gas distribution chamber 32; the upper end of the gas distribution pipe 31 is located below the rollers 22.

[0034] The upper end of the gas distribution pipe 31 is directly aligned with the joint hole of the sagger 21 on the roller 22; the joint hole is the contact position of two adjacent saggers 21; the gas distribution chamber 32 is formed by refractory bricks; the lower end of the gas distribution pipe 31 extends into the middle of the gas distribution chamber 32.

[0035] At least one inner air inlet pipe 33 is provided at the bottom of the air distribution chamber 32; a heating pipe 41 is coaxially arranged inside the inner air inlet pipe 33; two ceramic rings 42 are coaxially arranged on the outer wall of the heating pipe 41, and the ceramic rings 42 abut against the inner wall of the inner air inlet pipe 33; two spiral grooves 411 are symmetrically arranged on the inner wall of the heating pipe 41, and the spiral grooves 411 extend to the outside of the heating pipe 41.

[0036] One end of the inner air inlet pipe 33 is located in the middle of the air distribution chamber 32, and the other end is located on the outer wall of the furnace body 1; one end of the heating pipe 41 is located in the middle of the inner air inlet pipe 33, and the other end extends out from the outer wall of the furnace body 1; the end of the heating pipe 41 extending out of the furnace body is connected to the outer air inlet pipe 43.

[0037] At least one preheating box 11 is provided on the outer wall of the furnace body 1; the preheating box 11 has an opening at one end away from the furnace body 1; a sealing plate 112 for closing the opening is detachably connected inside the opening; an interface pipe 111 is provided at one end of the sealing plate 112 away from the furnace body 1; the interface pipe 111 is coaxially arranged with the external air inlet pipe 43, the inner diameter of the interface pipe 111 is larger than the outer diameter of the external air inlet pipe 43, and the end of the external air inlet pipe 43 is located in the middle of the interface pipe 111.

[0038] The heating tube 41 is a silicon carbide tube, which generates heat when energized; one end of the heating tube 41 extending out of the furnace body 1 is wrapped with an insulating cloth 44; the insulating cloth 44 wraps the electrode 46 around the outer wall of the heating tube 41; two clamps 45 are detachably connected to the outer periphery of the insulating cloth 44; the insulating cloth 44 is a glass fiber insulating cloth; the electrode 46 is an aluminum braided tape.

[0039] The preheating box 11 has terminals 5 running through its upper and lower ends respectively; the terminals 5 are detachably connected to locking screws 51 at their upper and lower ends respectively; the two electrodes 46 of the heating tube 41 are respectively disposed on adjacent terminals 5.

[0040] At least one annular base plate 12 is provided on the outer wall of the furnace body 1; the inner wall of the base plate 12 is provided with a chamfer at the end away from the furnace body 1; a flange 13 is provided at the end of the inner air inlet pipe 33 near the outer wall of the furnace body 1; the flange 13 is detachably connected to the base plate 12. The air distribution pipe 31, the inner air inlet pipe 33, the outer air inlet pipe 43, and the ceramic ring 42 are made of ceramic.

[0041] The above description is only a specific embodiment of the present utility model, but the technical features of the present utility model are not limited thereto. Any changes or modifications made by those skilled in the art within the scope of the present utility model are covered by the patent scope of the present utility model.

Claims

1. A roller hearth kiln spiral preheater characterized by: The furnace body, a plurality of roll bars arranged in the middle of the furnace body in a linear horizontal arrangement, a gas distribution cavity arranged in the lower part of the furnace body, and a plurality of uniformly distributed gas distribution pipes arranged on the gas distribution cavity; the upper end of the gas distribution pipe is below the roll bar; the inner bottom end of the gas distribution cavity is provided with at least one inner gas inlet pipe; the inner gas inlet pipe is coaxially provided with a heating pipe; wherein the process gas is introduced from the inside of the heating pipe; the outer wall of the heating pipe is coaxially provided with at least one porcelain ring, which is in contact with the inner wall of the inner gas inlet pipe; the inner wall of the heating pipe is symmetrically provided with two spiral grooves, which penetrate to the outside of the heating pipe.

2. The preheating device of claim 1, wherein: One end of the inner gas inlet pipe is located in the middle of the gas distribution cavity, and the other end is located on the outer wall of the furnace body; one end of the heating pipe is located in the middle of the inner gas inlet pipe, and the other end extends out of the outer wall of the furnace body; the end of the heating pipe extending out of the furnace body is inserted with an outer gas inlet pipe.

3. The preheating device of claim 2, wherein: The outer wall of the furnace body is provided with at least one preheating box; the end of the preheating box away from the furnace body is provided with a connector pipe; wherein the connector pipe is coaxially arranged with the outer gas inlet pipe, the inner diameter of the connector pipe is larger than the outer diameter of the outer gas inlet pipe, and the end of the outer gas inlet pipe is located in the middle of the connector pipe.

4. The preheating device of claim 3, wherein: The upper and lower ends of the preheating box are respectively provided with terminal posts; the upper and lower ends of the terminal post are respectively detachably connected with locking screws; the two electrodes of the heating pipe are respectively arranged on the adjacent terminal posts.

5. Preheating device according to any of claims 1-4, characterized in that The gas distribution cavity is formed by surrounding with refractory bricks; the lower end of the gas distribution pipe extends into the middle of the gas distribution cavity.

6. Preheating device according to any of claims 1-4, characterized in that The upper end of the gas distribution pipe is opposite to the sintering hole position on the sagger on the roll bar; the sintering hole position is the contact position of the two adjacent saggars.

7. A preheating device according to any of claims 3-4, characterized in that: The end of the preheating box away from the furnace body is provided with an opening; the end of the connector pipe towards the preheating box is provided with a sealing plate; the sealing plate is used to close the opening, and the sealing plate is detachably connected on the preheating box.

8. The preheating device according to any of claims 1-4, characterized in that: The outer wall of the furnace body is provided with at least one annular bottom disc; the end of the inner wall of the bottom disc away from the furnace body is provided with a guide angle; the end of the inner gas inlet pipe close to the outer wall of the furnace body is provided with a flange plate; the flange plate is detachably connected on the bottom disc.

9. The preheating device of claim 4, wherein: The end of the heating pipe extending out of the furnace body is wrapped with insulating cloth; the electrodes of the heating pipe are arranged between the insulating cloth and the outer wall of the heating pipe; the outer periphery of the insulating cloth is detachably connected with a clamp.

10. A preheating device according to any one of claims 2-4, characterized in that: The materials of the gas distribution pipe, the inner gas inlet pipe, the outer gas inlet pipe, and the porcelain ring are ceramic.

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