Silicon carbide sleeve heating structure

Abstract

The utility model provides a silicon carbide sleeve heating structure, which relates to the technical field of heating devices and comprises a heating tube and a silicon carbide sleeve, a plurality of ceramic isolation tubes are arranged at equal intervals along the length direction of the heating tube, and the ceramic isolation tubes are fixed on the heating tube in a penetrating and sleeving manner; the silicon carbide sleeve is sleeved outside the ceramic isolation tube; the outer surface of the heating tube and the inner wall surface of the silicon carbide sleeve are supported by the ceramic isolation tube to form a heat dissipation space; and the thickness of the ceramic isolation tube is 3-5 times that of the silicon carbide sleeve. The beneficial effects of the utility model are that the silicon carbide sleeve is sleeved on the heating tube, and the silicon carbide product has low porosity, so that the heating tube can be well protected; a silicon carbide product is high in bending strength at high temperature and more stable in strength at high temperature, and meanwhile, the silicon carbide is not deformed in a high-temperature state due to the extremely low thermal expansion coefficient of the silicon carbide; and finally, the heat conduction effect of the silicon carbide product is good, so that energy conservation is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of heating device equipment, in particular to a silicon carbide sleeve heating structure. Background Art

[0002] A kiln is a furnace used to fire ceramic objects and sculptures or to fuse enamel to the surface of metal objects. Currently, most kilns use electric heating components to heat up, and most of them use ceramic sleeves to wrap and protect the heating tubes or resistance wires in the electric heating components. Ceramic sleeves are tubular in shape and are mainly made of special materials such as alumina and silicon nitride that are resistant to high temperatures and corrosion. Because of their smooth and delicate surface, high hardness, strength and wear resistance, and almost unaffected by chemical substances, they are widely used in electric heating components.

[0003] Chinese patent CN200310121186.8 discloses an electric heater, which mentions the application of ceramic sleeves. The specific structure is as follows: it includes a ceramic sleeve sealed at the bottom, a ceramic core arranged in the ceramic sleeve, a resistance wire wound on the outer wall of the ceramic core, and a heat-conducting insulating powder arranged between the ceramic core and the ceramic sleeve. Since the resistance wire is wound on the outer wall of the ceramic core and the heat-conducting insulating powder is filled between the ceramic core and the ceramic sleeve, it can effectively transfer heat and effectively protect the resistance wire from being corroded or eroded by heat storage materials such as acids, alkalis, salts, metals and metal alloys at high temperatures, greatly extending the service life of the electric heater. At the same time, due to the protection of the ceramic sleeve, the electric heater can be directly buried in the heated medium when in use to achieve internal heating, reduce heat loss during the heating process, and improve heating efficiency and electric energy utilization.

[0004] However, after long-term application, we found that the ceramic sleeve not only affects the protection of the heating tube or resistance wire due to its high porosity, but also has low bending strength and unsatisfactory thermal conductivity, which restricts the further development of the heating device. Based on this, the utility model proposes a silicon carbide sleeve heating structure to overcome the above problems. Utility Model Content

[0005] The utility model overcomes the shortcomings of the prior art and provides a silicon carbide sleeve heating structure, which has the characteristics of low porosity, high bending strength and good heat conduction efficiency.

[0006] In order to solve the above technical problems, the utility model is achieved through the following technical solutions:

[0007] A silicon carbide sleeve heating structure comprises a heating tube and a silicon carbide sleeve, wherein a plurality of ceramic isolation tubes are arranged at equal intervals along the length direction of the heating tube, and the ceramic isolation tubes are fixed on the heating tube by sleeve insertion;

[0008] The silicon carbide sleeve is sleeved outside the ceramic isolation tube; the ceramic isolation tube and the silicon carbide sleeve are coaxially arranged; the ceramic isolation tube supports the outer surface of the heating tube and the inner wall surface of the silicon carbide sleeve to form a heat dissipation space;

[0009] The thickness of the ceramic isolation tube is 3 to 5 times the thickness of the silicon carbide sleeve; the length of the ceramic isolation tube is 8 to 12 times its thickness.

[0010] Furthermore, the outer surface of the ceramic isolation tube is smooth, and the inner surface is provided with a plurality of anti-slip teeth along a ring shape.

[0011] Furthermore, the anti-slip teeth are arranged in a trapezoidal shape, and heat dissipation positions are formed between adjacent anti-slip teeth.

[0012] Furthermore, both ends of the ceramic isolation tube are provided with smooth arc surfaces that are smoothly retracted inwards.

[0013] Furthermore, the thickness of the ceramic isolation tube is 12 to 15 mm.

[0014] Furthermore, the thickness of the silicon carbide sleeve is 1.5 to 3.8 mm.

[0015] Furthermore, an outward expansion opening is provided at the end of the silicon carbide sleeve; the outer diameter of the outward expansion opening is 1.25 to 1.36 times the inner diameter of the silicon carbide sleeve.

[0016] Furthermore, the outwardly expanded opening is formed with a vertically arranged connecting surface.

[0017] Furthermore, a one-way thread is formed on the inner surface of the anti-slip teeth.

[0018] Compared with the prior art, the beneficial effects of the utility model are:

[0019] This heating structure uses a silicon carbide sleeve to cover the heating tube. Since the porosity of silicon carbide products is low, it can provide good protection for the heating tube. Silicon carbide products have high bending strength at high temperatures and more stable strength at high temperatures. At the same time, due to the extremely low thermal expansion coefficient of silicon carbide, it will not deform at high temperatures. Finally, silicon carbide products have good thermal conductivity, which also helps to save energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings are used to provide a further understanding of the present invention and are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation of the present invention. In the accompanying drawings:

[0021] Figure 1 It is the overall diagram of the silicon carbide casing heating structure;

[0022] Figure 2 is a stereogram of one end of a silicon carbide sleeve;

[0023] Figure 3 It is a three-dimensional diagram of a ceramic isolation tube;

[0024] Figure 4 is a front view of a ceramic isolation tube;

[0025] Figure 5 is a side view of a ceramic isolation tube.

[0026] In the figure:

[0027] 1. Heating tube;

[0028] 2. Silicon carbide casing; 201. Outward expansion opening; 2011. Connection surface;

[0029] 3. Ceramic isolation tube; 301. Anti-slip teeth; 3011. One-way thread; 302. Heat dissipation position; 303. Smooth arc surface;

[0030] 4. Heat dissipation space. DETAILED DESCRIPTION

[0031] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0032] First embodiment

[0033] like Figure 1 , Figures 3 to 5 As shown, a silicon carbide sleeve heating structure includes a heating tube 1 and a silicon carbide sleeve 2. A plurality of ceramic isolation tubes 3 are equidistantly arranged along the length direction of the heating tube 1. The ceramic isolation tubes 3 are sleeved and fixed on the heating tube 1; the silicon carbide sleeve 2 is sleeved outside the ceramic isolation tube 3; the above structure is arranged according to the characteristics of silicon carbide products. Since silicon carbide products have the characteristics of low resistivity and good conductivity, the heating tube 1 and the silicon carbide sleeve 2 are separated by the ceramic isolation tube 3 in this structure, so that the silicon carbide sleeve 2 cannot contact with the heating tube 1 to avoid conduction.

[0034] The ceramic isolation tube 3 is coaxially arranged with the silicon carbide sleeve 2, and the structure is uniform and stable; the ceramic isolation tube 3 supports the outer surface of the heating tube 1 and the inner wall surface of the silicon carbide sleeve 2 to form a heat dissipation space 4, which, as described above, prevents the heating tube 1 from conducting electricity to the silicon carbide sleeve 2, and also allows the heat generated by the heating tube 1 to diffuse to the silicon carbide sleeve 2 through the heat dissipation space 4.

[0035] from Figure 1It can be seen that the thickness of the ceramic isolation tube 3 is 3 to 5 times the thickness of the silicon carbide sleeve 2; the length of the ceramic isolation tube 3 is 8 to 12 times its thickness; in this embodiment, the thickness of the ceramic isolation tube 3 is 3.5 times the thickness of the silicon carbide sleeve 2; the length of the ceramic isolation tube 3 is 10 times its thickness.

[0036] The outer surface of the ceramic isolation tube 3 is smooth, and the inner surface is provided with a plurality of anti-slip teeth 301 along a ring shape. During installation, the anti-slip teeth 301 are in contact with the outer surface of the heating tube 1. During installation, the ceramic isolation tube 3 is first mounted on the heating tube 1, and then the silicon carbide sleeve 2 is inserted and installed. Therefore, the provision of the anti-slip teeth 301 can enhance the fixing effect of the ceramic isolation tube 3 on the heating tube 1, and avoid the silicon carbide sleeve 2 from moving on its own when inserted. The smooth outer surface of the ceramic isolation tube 3 also enables it to slide in contact with the inner wall of the silicon carbide sleeve 2, which is beneficial to the installation of the silicon carbide sleeve 2.

[0037] The anti-slip teeth 301 are arranged in a trapezoidal shape, which can reduce the contact surface between the anti-slip teeth 301 and the heating tube 1 and avoid blocking the surface of the heating tube 1; a heat dissipation position 302 is formed between adjacent anti-slip teeth 301, which is also conducive to the heat dissipation of the heating tube 1.

[0038] Both ends of the ceramic isolation tube 3 are provided with smooth arc surfaces 303 that are smoothly retracted inwards. The smooth arc surfaces 303 are also convenient for inserting and installing the silicon carbide sleeve 2.

[0039] The thickness of the ceramic isolation tube 3 is 12 to 15 mm, and the thickness of the silicon carbide sleeve 2 is 1.5 to 3.8 mm. In the present embodiment, the thickness of the ceramic isolation tube 3 is 13 mm, and the thickness of the silicon carbide sleeve 2 is 2.5 mm.

[0040] like Figure 3 As shown, the inner surface of the anti-slip teeth 301 is formed with a one-way thread 3011; the purpose of this arrangement is that when the ceramic isolation tube 3 is installed on the heating tube 1, the ceramic isolation tube 3 can be pushed forward while being rotated along the lines of the one-way thread 3011 by hand, which helps to install the ceramic isolation tube 3; when the ceramic isolation tube 3 is assembled to a suitable position and stopped, the one-way thread 3011 can actually enhance the friction between the ceramic isolation tube 1 and the heating tube 1, thereby preventing the ceramic isolation tube 3 from moving on its own.

[0041] Second embodiment

[0042] like Figure 2As shown, it is an improvement on the first embodiment, and the difference of this improvement is that an outward expansion opening 201 is provided at the end of the silicon carbide sleeve 2; the outer diameter of the outward expansion opening 201 is 1.25 to 1.36 times the inner diameter of the silicon carbide sleeve 2; in this embodiment, the outer diameter of the outward expansion opening 201 is 1.3 times the inner diameter of the silicon carbide sleeve 2; the outward expansion opening 201 is formed with a vertically arranged connection surface 2011. Firstly, the setting of the outward expansion opening 201 is conducive to the sleeve installation of the silicon carbide sleeve 2. In addition, when more than two silicon carbide sleeves 2 need to be spliced ​​for use, the connection surfaces 2011 of the adjacent silicon carbide sleeves 2 can be glued after being coated; the connection surface 2011 formed by the outward expansion opening 201 is conducive to increasing the amount of glue coating and enhancing the fixing effect of the adjacent silicon carbide sleeves 2.

[0043] The applicant has found that silicon carbide casing has the following advantages compared with general ceramic tubes:

[0044] (1) Protective effect:

[0045] The porosity of ceramic sleeve products is generally 20%~50%, while the porosity of silicon carbide products is less than 0.2%, which can provide better protection for the heating tube;

[0046] (2) Safety function:

[0047] The bending strength of silicon carbide products can reach 389Mpa at high temperatures, while that of general ceramic bushing products is only 60Mpa; in addition, silicon carbide products have better thermal shock resistance and more stable strength at high temperatures; at the same time, the extremely low thermal expansion coefficient of silicon carbide prevents it from deforming at high temperatures;

[0048] (3) Energy saving effect:

[0049] At present, ceramic sleeves are commonly used, with a thermal conductivity of 30 W / (m·K) at room temperature. As the temperature rises, the thermal conductivity gradually increases. In high temperature environments, the thermal conductivity of ceramic sleeves can reach 150 W / (m·K); the thermal conductivity of silicon carbide can reach 120-180 W / (m·K) at room temperature, which is close to the thermal conductivity of metals. Under the same conditions, the thermal conductivity efficiency of silicon carbide tubes can reach up to 6 times that of alumina. Therefore, compared with kilns equipped with the same number of ceramic sleeves and silicon carbide sleeves, the energy consumption of using silicon carbide sleeves is only 1 / 5 to 1 / 6 of that of using ceramic sleeves.

[0050] Based on the above advantages, the heating structure of the silicon carbide sleeve product used in this application also has the above advantages.

[0051] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. However, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A silicon carbide sleeve heating structure, characterized in that: It includes a heating tube and a silicon carbide sleeve, and a plurality of ceramic isolation tubes are arranged at equal intervals along the length direction of the heating tube, and the ceramic isolation tubes are fixed on the heating tube through the sleeve; The silicon carbide sleeve is sleeved outside the ceramic isolation tube; the ceramic isolation tube and the silicon carbide sleeve are coaxially arranged; the ceramic isolation tube supports the outer surface of the heating tube and the inner wall surface of the silicon carbide sleeve to form a heat dissipation space; The thickness of the ceramic isolation tube is 3 to 5 times the thickness of the silicon carbide sleeve; the length of the ceramic isolation tube is 8 to 12 times its thickness.

2. A silicon carbide sleeve heating structure according to claim 1, characterized in that: The outer surface of the ceramic isolation tube is smooth, and the inner surface is provided with a plurality of anti-slip teeth along a ring shape.

3. A silicon carbide sleeve heating structure according to claim 2, characterized in that: The anti-slip teeth are arranged in a trapezoidal shape, and heat dissipation positions are formed between adjacent anti-slip teeth.

4. A silicon carbide sleeve heating structure according to claim 2 or 3, characterized in that: Both ends of the ceramic isolation tube are provided with smooth arc surfaces that are smoothly retracted inwards.

5. The silicon carbide sleeve heating structure according to claim 1, characterized in that: The thickness of the ceramic isolation tube is 12 to 15 mm.

6. The silicon carbide sleeve heating structure according to claim 1, characterized in that: The thickness of the silicon carbide sleeve is 1.5 to 3.8 mm.

7. A silicon carbide sleeve heating structure according to claim 5 or 6, characterized in that: The end of the silicon carbide sleeve is provided with an outward expansion opening; the outer diameter of the outward expansion opening is 1.25 to 1.36 times the inner diameter of the silicon carbide sleeve.

8. The silicon carbide sleeve heating structure according to claim 7, characterized in that: The outwardly expanded opening is formed with a vertically arranged connecting surface.

9. The silicon carbide sleeve heating structure according to claim 2, characterized in that: The inner surface of the anti-slip teeth is formed with a one-way thread.

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