A device to ensure the centering of the powder-filled resistance wire of the heating tube

Abstract

The utility model discloses a device for ensuring that the resistance wire of a heating tube is centered when filling powder, and relates to the field of heating tube production, including a tube, a powder-adding outer rod inserted into the tube, a powder-adding inner rod detachably inserted into the powder-adding outer rod, and a resistance wire inserted into the powder-adding inner rod, wherein a plurality of centering wings are arranged on the outer wall of the powder-adding outer rod, and the centering wings are in contact with and fit with the inner wall of the powder-adding outer rod, so that the powder-adding inner rod is centered relative to the powder-adding outer rod. The utility model welds a plurality of centering wings on the outer wall of the powder-adding inner rod, and when the powder-adding inner rod is pulled out of the powder-adding outer rod for powder filling, the centering wings are always in contact with and fit with the inner wall of the powder-adding outer rod, thereby effectively ensuring the coaxiality of the resistance wire and the tube, and avoiding the eccentricity of the resistance wire in the tube, which results in poor pressure resistance of the product; a conical surface is arranged on the sealing portion of the powder-adding nozzle, which can cooperate with the mouth of the powder-adding outer rod for sealing, and prevents the magnesium oxide powder filled between the powder-adding outer rod and the powder-adding inner rod from leaking out.

Description

Technical Field

[0001] The utility model relates to the field of heating tube production, in particular to a device for ensuring that a powder-filled resistance wire of a heating tube is centered. Background Art

[0002] When the heating tube is produced, an electric heating wire is installed in a seamless metal tube (carbon steel tube, titanium tube, stainless steel tube, copper tube), and then the gap is filled with magnesium oxide powder with good thermal conductivity and insulation, and then the tube is shrunk and finally processed into various shapes required by the user.

[0003] However, the existing heating tube adopts a disengaged powder adding nozzle. After the powder adding nozzle is disengaged from the outer rod, it is easy to shake during the powder adding process, causing the resistance wire to be eccentric. In actual production, the proportion of poor pressure resistance of powder adding is as high as 5%, which increases the production cost in disguise and causes unnecessary waste, which needs to be improved. Utility Model Content

[0004] The utility model aims to overcome the shortcomings of the prior art and provide a device to ensure that the resistance wire of the powder filling of the heating tube is centered, so that the powder adding nozzle remains concentric after being disengaged from the outer rod, thereby ensuring that the resistance wire is located in the center of the heating tube.

[0005] The purpose of the utility model is achieved through the following technical scheme: this device for ensuring that the resistance wire of the powder-filled heating tube is centered comprises a tube, a powder-filling outer rod inserted into the tube, a powder-filling inner rod detachably inserted into the powder-filling outer rod, and a resistance wire inserted into the powder-filling inner rod, a plurality of centering wings are arranged on the outer wall of the powder-filling outer rod, the centering wings are in contact with and fit with the inner wall of the powder-filling outer rod, so that the powder-filling inner rod is centered relative to the powder-filling outer rod.

[0006] As a further technical solution, a powder adding nozzle is provided at one end of the powder adding inner rod, and a sealing portion is provided at the connection between the powder adding nozzle and the powder adding inner rod for cooperating with the mouth sealing of the powder adding outer rod.

[0007] As a further technical solution, during the powder filling process, when the sealing part is separated from the mouth of the powder adding outer rod, magnesium oxide powder is poured into the space between the powder adding outer rod and the powder adding inner rod from the gap formed between the sealing part and the mouth of the powder adding outer rod.

[0008] As a further technical solution, a conical surface is provided on the sealing portion to cooperate with the mouth of the powder adding outer rod to form a conical surface seal.

[0009] As a further technical solution, the centering wing is arranged at one end of the powder adding inner rod close to the sealing portion, and the centering wing is evenly distributed along the circumference of the powder adding inner rod.

[0010] As a further technical solution, the centering wing is fixed to the powder adding inner rod by welding.

[0011] The beneficial effects of the utility model are:

[0012] 1. Weld multiple centering wings on the outer wall of the powder adding inner rod. When the powder adding inner rod is pulled out of the powder adding outer rod for powder filling, the centering wings are always in contact with the inner wall of the powder adding outer rod, thereby effectively ensuring the coaxiality of the resistance wire and the pipe, avoiding the eccentricity of the resistance wire in the pipe, which leads to poor pressure resistance of the product;

[0013] 2. A conical surface is arranged on the sealing part of the powder adding nozzle, which can cooperate with the mouth of the powder adding outer rod for sealing, so as to prevent the magnesium oxide powder poured between the powder adding outer rod and the powder adding inner rod from leaking out. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the utility model.

[0015] Figure 2 It is a schematic diagram of the structure of the utility model when powder is filled.

[0016] Figure 3 This is a schematic diagram of the structure of the utility model after powder filling is completed.

[0017] Figure 4 for Figure 2 A partial enlarged schematic diagram of area A in the middle.

[0018] Figure 5 for Figure 3 A partial enlarged schematic diagram of area B in the middle.

[0019] Description of the reference numerals: pipe 1, powder adding outer rod 2, centering wing 3, powder adding inner rod 4, powder adding nozzle 5, magnesium oxide powder 6, resistance wire 7, sealing part 8, cone surface 9, gap 10. DETAILED DESCRIPTION

[0020] The utility model will be described in detail below with reference to the accompanying drawings:

[0021] Example: As shown in the attached Figures 1 to 5 As shown, the device for ensuring the centering of the powder-filled resistance wire of the heating tube comprises a tube 1, a powder-filling outer rod 2, a centering wing 3, a powder-filling inner rod 4, a powder-filling nozzle 5, magnesium oxide powder 6, a resistance wire 7, a sealing portion 8, a conical surface 9 and a gap 10.

[0022] Reference Figure 3 The powder adding outer rod 2 is installed in the tube material 1 of the heating tube, and the powder adding inner rod 4 is pluggable in the powder adding outer rod 2, and the resistance wire 7 is inserted in the powder adding inner rod 4. Figure 1 As shown, a plurality of centering wings 3 (preferably three) are welded and fixed on the outer wall of the powder adding outer rod 2, as shown in FIG. Figure 2 , 3As shown, during the process of inserting and removing the powder adding inner rod 4 relative to the powder adding outer rod 2, the centering wing 3 always keeps in contact with the inner wall of the powder adding outer rod 2, so that the powder adding inner rod 4 (resistance wire 7) is centered relative to the powder adding outer rod 2.

[0023] like Figure 1 As shown, a powder adding nozzle 5 is provided at the lower end of the powder adding inner rod 4, and a sealing portion 8 is provided at the connection between the powder adding nozzle 5 and the powder adding inner rod 4. Figure 3 , 5 As shown, preferably, a conical surface 9 is provided on the sealing portion 8, which can form a conical surface seal with the mouth of the powder adding outer rod 2. The centering wing 3 is provided at one end of the powder adding inner rod 4 close to the sealing portion 8, and the centering wing 3 is evenly distributed along the circumferential direction of the powder adding inner rod 4.

[0024] The working process of this utility model:

[0025] During the powder filling process, Figure 2 , 4 As shown, when the sealing portion 8 (conical surface 9) is separated from the mouth of the powder adding outer rod 2, the magnesium oxide powder 6 is poured into the gap 10 formed between the sealing portion 8 and the mouth of the powder adding outer rod 2 and the powder adding inner rod 4. At this time, since the centering wing 3 always keeps in contact with the inner wall of the powder adding outer rod 2, the powder adding inner rod 4 (resistance wire 7) is centered relative to the powder adding outer rod 2, and the powder adding inner rod 4 will not shake, avoiding the eccentricity of the resistance wire in the pipe, which leads to poor pressure resistance of the product.

[0026] After filling powder, Figure 3 , 5 As shown, the powder adding inner rod 4 is inserted tightly relative to the powder adding outer rod 2, and the conical surface 9 forms a conical surface seal with the mouth of the powder adding outer rod 2 to block the magnesium oxide powder 6 and prevent it from leaking out.

[0027] It is understandable that, for those skilled in the art, any equivalent replacement or change to the technical solution and the concept of the utility model should fall within the protection scope of the claims attached to the utility model.

Claims

1. A device to ensure that the powder-filled resistance wire of a heating tube is centered, characterized in that: The invention comprises a pipe (1), a powder adding outer rod (2) inserted into the pipe (1), a powder adding inner rod (4) which can be detachably inserted into the powder adding outer rod (2), and a resistance wire (7) inserted into the powder adding inner rod (4). A plurality of centering wings (3) are arranged on the outer wall of the powder adding outer rod (2). The centering wings (3) are in contact with and fit the inner wall of the powder adding outer rod (2), so that the powder adding inner rod (4) is centrally positioned relative to the powder adding outer rod (2).

2. The device for ensuring the centering of the powder-filled resistance wire of the heating tube according to claim 1 is characterized in that: A powder adding nozzle (5) is arranged at one end of the powder adding inner rod (4), and a sealing portion (8) is arranged at the connection between the powder adding nozzle (5) and the powder adding inner rod (4) for cooperating with the mouth sealing of the powder adding outer rod (2).

3. The device for ensuring the centering of the powder-filled resistance wire of the heating tube according to claim 2 is characterized in that: During the powder filling process, when the sealing portion (8) is separated from the mouth of the powder adding outer rod (2), the magnesium oxide powder (6) is poured into the space between the powder adding outer rod (2) and the powder adding inner rod (4) from the gap (10) formed between the sealing portion (8) and the mouth of the powder adding outer rod (2).

4. The device for ensuring the centering of the powder-filled resistance wire of the heating tube according to claim 3 is characterized in that: The sealing portion (8) is provided with a conical surface (9) for cooperating with the mouth of the powder adding outer rod (2) to form a conical surface seal.

5. The device for ensuring the centering of the powder-filled resistance wire of the heating tube according to claim 2 is characterized in that: The centering wings (3) are arranged at one end of the powder adding inner rod (4) close to the sealing portion (8), and the centering wings (3) are evenly distributed along the circumference of the powder adding inner rod (4).

6. The device for ensuring the centering of the powder-filled resistance wire of the heating tube according to claim 1 is characterized in that: The centering wing (3) is fixed to the powder adding inner rod (4) by welding.

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