Heating body and heater for sintering furnace

Abstract

The utility model discloses a heating body and a heater for a sintering furnace, and belongs to the technical field of sintering furnaces. The heating body comprises a sleeve, a heating wire, a fixed seat, a sealing piece and a pressing piece, the heating wire is arranged in the sleeve, the fixing base is arranged on a furnace body, the two ends of the sleeve are fixed in the fixing base, the sealing piece is arranged between the fixing base and the side wall of the sleeve, and the pressing piece is arranged at the end of the sleeve in a sleeving mode and connected with the inner wall of the fixing base. The utility model further provides a heater for the sintering furnace, the heater comprises the heating body and a furnace body, and the heating body is installed on the side wall of the furnace body and located in the furnace body. According to the utility model, the isolation between the heating wire and wet hydrogen is realized, and the problems that the heating body is easy to erode and the service life is short are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of sintering furnaces, in particular to a heating element and a heater used for a sintering furnace. Background Art

[0002] The continuous sintering furnace is a key equipment for the production of nuclear fuel pellets, with the advantages of high output, low energy consumption, and good product consistency. The continuous sintering furnace of the wet hydrogen sintering process has an operating temperature of 1750°C, molybdenum wire as the heating element, and humidified hydrogen as the atmosphere in the furnace, with a dew point requirement of 20°C to 30°C.

[0003] The molybdenum heating element of the traditional wet hydrogen process sintering furnace is a "naked" structure, with molybdenum wire or molybdenum belt hung on the side wall of the furnace. Wet hydrogen enters the heating element area outside the muffle, causing the heating element to be corroded, resulting in poor equipment reliability and short service life. Utility Model Content

[0004] The purpose of the utility model is to overcome the above technical deficiencies, provide a heating element and a heater for a sintering furnace, and solve the technical problems in the prior art that the heating element is easily corroded and has a short service life.

[0005] In order to achieve the above technical objectives, the technical solution of the utility model provides a heating element, including a sleeve, a heating wire, a fixing seat, a sealing member and a pressing member; the heating wire is arranged in the sleeve, the fixing seat is arranged on the furnace body, the two ends of the sleeve are fixed in the fixing seat, the sealing member is arranged between the fixing seat and the side wall of the sleeve, and the pressing member is sleeved on the end of the sleeve and connected to the inner wall of the fixing seat.

[0006] In some embodiments, the sealing member is a sealing packing, and the sealing packing is wound around the sleeve.

[0007] In some embodiments, the clamping member is a clamping nut, and the clamping nut is connected to the fixing seat.

[0008] In some embodiments, the middle portion of the heating wire is a spiral heating wire.

[0009] In some embodiments, the diameter of the spiral portion of the heating wire is 40 to 60 mm; the inner diameter of the sleeve is 2 to 5 mm larger than the outer diameter of the spiral portion of the heating wire.

[0010] In some embodiments, the heating wire has a wire diameter of 2 to 5 mm.

[0011] In some embodiments, the heating wire is a spiral molybdenum wire.

[0012] In some embodiments, the sleeve is a ceramic sleeve.

[0013] The utility model also provides a heater for a sintering furnace, comprising the heating element and a furnace body, wherein the heating element is installed on the side wall of the furnace body and is located inside the furnace body.

[0014] In some embodiments, there are two heating elements, which are respectively disposed on the side walls of the top end and the bottom end of the furnace body.

[0015] Compared with the prior art, the beneficial effects of the utility model include: the heating element proposed in the utility model includes a sleeve, a heating wire, a fixing seat, a sealing member and a pressing member; the heating wire is arranged in the sleeve, the fixing seat is arranged on the furnace body, the two ends of the sleeve are fixed in the fixing seat, the sealing member is arranged between the fixing seat and the side wall of the sleeve, the pressing member is sleeved on the end of the sleeve and connected to the inner wall of the fixing seat, the heating wire is protected in the sleeve, the heating wire is isolated from wet hydrogen, and the problem that the heating element is easily corroded and has a short service life is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the heating body of Example 1 of the utility model.

[0017] Figure 2 It is a schematic diagram of the structure of the heating wire of Example 1 of the utility model.

[0018] Figure 3 It is a schematic structural diagram of a heater for a sintering furnace according to Example 2 of the utility model.

[0019] Figure 4 It is a schematic structural diagram of the inflation component of Example 2 of the utility model.

[0020] Description of reference numerals:

[0021] 1. Muffle; 2. Furnace body; 3. Heating element; 31. Sleeve; 32. Heating wire; 33. Fixing seat; 34. Seal; 35. Pressing piece; 4. Inflating assembly; 41. Air inlet pipe; 42. Pressure reducing valve; 421. First-stage pressure reducing valve; 422. Second-stage pressure reducing valve; 43. Solenoid valve; 44. Plug valve; 45. Pressure sensor; 5. Guide block. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0023] Example 1

[0024] Combination Figure 1-3The present embodiment proposes a heating body 3, comprising a sleeve 31, a heating wire 32, a fixing seat 33, a sealing member 34 and a pressing member 35; the heating wire 32 is arranged in the sleeve 31, the fixing seat 33 is arranged on the furnace body 2, both ends of the sleeve 31 are fixed in the fixing seat 33, the sealing member 34 is arranged between the fixing seat 33 and the side wall of the sleeve 31, and the pressing member 35 is sleeved on the end of the sleeve 31 and connected to the inner wall of the fixing seat 33.

[0025] The heating wire 32 is protected and installed by the sleeve 31 and other components, which realizes a firm installation and avoids contact with the outside world, thereby extending its service life. In this embodiment, two heating elements 3 are respectively provided at the upper and lower ends of the furnace body 2, and the muffle 1 is located between the two heating elements 3.

[0026] On the basis of the above embodiment, the sealing member 34 of this embodiment is a sealing packing, which is wound around the sleeve 31 to fill the gap between the sleeve 31 and the fixing seat 33.

[0027] On the basis of the above embodiment, the clamping member 35 of this embodiment is a clamping nut, which is connected to the fixing seat 33. The clamping nut is connected to the fixing seat 33, and the sleeve 31 can be fixed on the fixing seat 33 while the sleeve still has a certain expansion space.

[0028] Based on the above embodiment, the middle part of the heating wire 32 of this embodiment is a spiral heating wire. The heating wire 32 adopts a "spiral" molybdenum wire, the wire diameter d is φ2-5mm, the spiral wire diameter is 40-60mm, and the pitch S≥2d.

[0029] The heating wire in this embodiment is a molybdenum heating wire, and the sleeve 31 outside the heating wire is a ceramic sleeve. The inner diameter of the sleeve 31 is 2 to 5 mm larger than the outer diameter of the spiral portion of the heating wire.

[0030] The ceramic sleeve in this embodiment is made of high-purity alumina, with a purity of ≥99.3%, compressive strength ≥100MPa, and room-temperature flexural strength ≥20Mpa. The ceramic sleeve is formed by isostatic pressing, and the forming mold is made of high-strength alloy steel to reduce pollution.

[0031] The firing temperature of the ceramic sleeve is ≥1750℃, with stable structure and high strength.

[0032] The ceramic sleeve is installed in such a way that it can freely expand and contract during the heating and cooling process of the furnace.

[0033] Example 2

[0034] Combination Figure 1-4 This embodiment provides a heater for a sintering furnace, comprising the heating element 3 of Embodiment 2 and a furnace body 2; two heating elements 3 are respectively provided at the upper and lower ends of the furnace body 2, and the muffle 1 is located between the two heating elements 3.

[0035] Furthermore, the heater for the sintering furnace in this embodiment further includes a muffle 1 , which is installed in the furnace body 2 .

[0036] On the basis of the above embodiment, this embodiment also includes an inflation component 4, which is arranged on the side wall of the furnace body 2 and connected to the interior of the furnace body 2. The inflation component 4 is used to blow dry hydrogen to the outer side of the muffle 1. The dry hydrogen is filled into the heating element 3 area to maintain a pressure greater than that inside the muffle 1. The external pressure of the muffle 1 is higher than that inside, ensuring that the internal wet hydrogen will not flow out to the heating element 3 area.

[0037] On the basis of the above-mentioned embodiments, the gas filling assembly 4 of this embodiment includes an air inlet pipe 41, a pressure reducing valve 42, a solenoid valve 43 and a plug valve 44. The air inlet pipe 41 is arranged on the side wall of the furnace body 2 and communicates with the interior of the furnace body 2. The plug valve 44, the solenoid valve 43 and the pressure reducing valve 42 are arranged on the air inlet pipe 41 outside the furnace body 2 in order from near to far from the furnace body 2. In this embodiment, the pressure reducing valve 42 is set to two, namely, a primary pressure reducing valve 421 and a secondary pressure reducing valve 422. The primary pressure reducing valve 421 reduces the pressure of dry hydrogen to 10kPa, and the secondary pressure reducing valve 422 reduces the pressure of dry hydrogen to 2kPa to ensure pressure stability. The plug valve 44 is used for pressure fine-tuning to adjust the pressure to 0.5kPa. The solenoid valve 43 is used to open or close the air inlet pipe 41.

[0038] On the basis of the above embodiment, the gas filling assembly 4 of this embodiment further includes a pressure sensor 45, which is arranged on the air inlet pipe 41 outside the furnace body 2, and the installation position of the pressure sensor 45 is closer to the furnace body 2 than the stopcock 44. The pressure sensor 45 is used to monitor the pressure of hydrogen.

[0039] On the basis of the above embodiment, this embodiment further includes a guide block 5 disposed in the furnace body 2, a groove is disposed on the upper surface of the guide block 5 (not shown in the figure but easy to understand), and the muffle 1 is disposed in the groove of the guide block 5. The guide block 5 can prevent the muffle 1 from deviating under the preload state.

[0040] The heater for the sintering furnace proposed by the utility model can be used as a heater for a continuous sintering furnace in a wet hydrogen process, isolating the wet hydrogen atmosphere from the molybdenum heating wire, and greatly extending the life of the heating wire 32. The molybdenum heating wire is provided with a ceramic sleeve to isolate the atmosphere in the furnace from the molybdenum heating element, ensuring that the heating element is not corroded by wet hydrogen, and at the same time, the heating element 3 can be replaced without stopping the furnace, greatly extending the continuous use time of the equipment.

[0041] The specific implementation methods of the utility model described above do not constitute a limitation on the protection scope of the utility model. Any other corresponding changes and modifications made according to the technical concept of the utility model should be included in the protection scope of the claims of the utility model.

Claims

1. A heating element, characterized in that: It includes a sleeve, a heating wire, a fixing seat, a sealing member and a pressing member; the heating wire is arranged in the sleeve, the fixing seat is arranged on the furnace body, the two ends of the sleeve are fixed in the fixing seat, the sealing member is arranged between the fixing seat and the side wall of the sleeve, and the pressing member is sleeved on the end of the sleeve and connected to the inner wall of the fixing seat.

2. The heating element according to claim 1, characterized in that: The sealing element is a sealing packing, and the sealing packing is wound on the sleeve.

3. The heating element according to claim 1, characterized in that: The clamping piece is a clamping nut, and the clamping nut is connected to the fixing seat.

4. The heating element according to claim 1, characterized in that: The middle part of the heating wire is a spiral heating wire.

5. The heating element according to claim 4, characterized in that: The diameter of the spiral part of the heating wire is 40-60 mm; the inner diameter of the sleeve is 2-5 mm larger than the outer diameter of the spiral part of the heating wire.

6. The heating element according to claim 4, characterized in that: The wire diameter of the heating wire is 2-5 mm.

7. The heating element according to claim 4, characterized in that: The heating wire is a spiral molybdenum wire.

8. The heating element according to claim 1, characterized in that The sleeve is a ceramic sleeve.

9. A heater for a sintering furnace, characterized in that: The invention comprises the heating element and the furnace body as described in any one of claims 1 to 8, wherein the heating element is installed on the side wall of the furnace body and is located inside the furnace body.

10. The heater for a sintering furnace according to claim 9, characterized in that: The number of the heating elements is two, which are respectively arranged on the side walls of the top end and the bottom end of the furnace body.

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