End sealing structure of double-end high-voltage heating pipe

Abstract

The utility model belongs to the technical field of electric heating tubes, and particularly relates to an end sealing structure of a double-end high-voltage heating tube, which comprises an electric heating tube consisting of a metal outer tube, an electric heating wire and a lead-out rod. Two symmetrically arranged electric heating wires and two symmetrically arranged lead-out rods are mounted in the electric heating pipe; according to the utility model, the requirement of an electrical gap under a high-voltage condition is met, the adopted insulating media are insulating materials with high dielectric strength, a certain angle is formed inside the insulating assembly to enlarge the distance between the two lead-out rods, and the insulating materials are arranged outside the lead-out rods, so that the lead-out rods can be separated from each other when the lead-out rods are in the air; and the requirement of an electrical gap can still be met. And meanwhile, the requirement of creepage under a high-voltage condition is met. And the difficulty of process preparation is reduced, and the assembly component can be independently prepared. Meanwhile, compared with a low-voltage electric heater, the high-voltage electric heater saves the power distribution cost of an electric heater system and improves the comprehensive electro-thermal conversion efficiency of the system.

Description

Technical Field

[0001] This utility model belongs to the field of electric heating tube technology, specifically a double-ended high-voltage heating tube end sealing structure. Background Technology

[0002] An electric heating element is a heating element that converts electrical energy into heat energy, widely used in various fields such as industry, home use, and laboratory equipment. An electric heating element mainly consists of a metal shell, heating wire, insulation layer, sealing structure, and lead-out rod. Its heating principle is based on Joule's law, which states that when current flows through a conductor, the conductor's resistance causes some electrical energy to be converted into heat energy. The resistance wire generates heat after being energized, which is transferred to the outside of the heating element through conduction, heating the surrounding medium, such as water, air, or oil. Electric heating elements can not only operate stably for extended periods in high-temperature environments, but also, during the heating process, can be precisely controlled according to actual needs by combining with thyristors or other switching elements based on control principles.

[0003] The main challenge in high-voltage electric heating elements is ensuring safe electrical distances under high-voltage conditions. Generally, the higher the voltage, the greater the required safety distance. This means a larger distance between the heating element's lead rod and the heating wire, necessitating a thicker heating element tube. The distance between different heating elements also increases, leading to a larger electric heater assembled from them. For double-ended heating elements, without end treatment under high voltage, a greater creepage distance is needed between the lead rod and the outer metal tube of the heating element. Furthermore, since both lead rods originate from the same end, the distance between them also increases. If the ends of double-ended heating elements are not treated, a larger tube diameter is required to meet electrical performance requirements. However, a tube diameter that is too large cannot meet heat dissipation requirements, and excessively large diameters are impractical in manufacturing and use.

[0004] Therefore, this utility model provides a sealing structure for the ends of a double-ended high-voltage heating tube. Utility Model Content

[0005] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0006] The technical solution adopted by this utility model to solve its technical problem is as follows: The end sealing structure of the double-ended high-voltage heating tube of this utility model includes an electric heating tube, which is composed of a metal outer tube, an electric heating wire, and a lead-out rod; two symmetrically arranged electric heating wires and two symmetrically arranged lead-out rods are installed inside the electric heating tube, the electric heating wires are connected to the lead-out rods, an insulating assembly is provided on the outside of the lead-out rods, an insulating medium is filled between the electric heating wires and the metal outer tube, an insulating material is filled between the insulating medium and the electric heating wires, and the cross-section of the metal outer tube is U-shaped.

[0007] Furthermore, the sides of the two leads are stepped, the distance between the two leads inside the insulating assembly is small, and the distance between the two leads outside the insulating assembly is larger than the distance between the leads inside the insulating assembly.

[0008] Furthermore, two grooves are provided at the port of the metal outer tube, and a groove is provided at the center of the insulating medium near one end of the insulating assembly.

[0009] Furthermore, the insulating medium is a ceramic material, and the insulating material is in powder form.

[0010] Furthermore, the insulating assembly is made of an insulating material with a relatively high permittivity.

[0011] Furthermore, the insulating assembly and the metal outer tube are connected by insulating adhesive.

[0012] Furthermore, the portion of the lead-out rod inside the insulating assembly and the portion away from the insulating assembly and exposed to air are coated with an insulating layer, while the portion of the lead-out rod near the heating wire is not coated with an insulating layer.

[0013] The beneficial effects of this utility model are as follows:

[0014] 1. The end-sealing structure of the double-ended high-voltage heating tube described in this utility model meets the electrical clearance requirements under high-voltage conditions. The insulating medium used is a high-dielectric-strength insulating material. The insulating assembly has an angle that widens the distance between the two leads, and insulating material is placed on the outside of the leads. Even when the leads are in the air, the electrical clearance requirements are still met. It also meets the creepage requirements under high-voltage conditions. The manufacturing process is simplified, and the assembly can be manufactured separately. This also saves on the power distribution costs of the electric heater system and improves the overall electrothermal conversion efficiency of the system.

[0015] 2. The end sealing structure of the double-ended high-voltage heating tube of this utility model increases the distance between the two lead-out rods at the end by increasing the distance between them through the insulating assembly, thereby increasing the electrical clearance between the two lead-out rods. The part of the lead-out rods extending out of the insulating assembly and the part inside the insulating assembly are both coated with an insulating layer to avoid any exposed parts in the air, thus meeting the requirements for electrical safety distance. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the cross-sectional structure of the end of the electric heating tube in this utility model;

[0018] Figure 2 This is a cross-sectional view of the double-ended electric heating tube in this utility model.

[0019] In the diagram: 1. Insulating layer; 2. Lead-out rod; 3. Insulating assembly; 4. Insulating medium; 5. Metal outer tube; 6. Electric heating wire; 7. Insulating material; 8. Electric heating tube. Detailed Implementation

[0020] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the present utility model will be further described below in conjunction with specific embodiments.

[0021] like Figures 1 to 2 As shown in the embodiment of this utility model, a double-ended high-voltage heating tube end sealing structure includes an electric heating tube 8, which consists of a metal outer tube 5, electric heating wires 6, and lead-out rods 2. Two symmetrically arranged electric heating wires 6 and two symmetrically arranged lead-out rods 2 are installed inside the electric heating tube 8. The electric heating wires 6 are connected to the lead-out rods 2. An insulating assembly 3 is provided outside the lead-out rods 2. An insulating medium 4 is filled between the electric heating wires 6 and the metal outer tube 5, and an insulating material 7 is filled between the insulating medium 4 and the electric heating wires 6. The cross-section of the metal outer tube 5 is U-shaped. The sides of the two lead-out rods 2 are stepped. The distance between the two lead-out rods 2 inside the insulating assembly 3 is small, while the distance between the two lead-out rods 2 outside the insulating assembly 3 is larger than the distance inside the insulating assembly 3. Two grooves are provided at the ends of the metal outer tube 5, and a groove is provided at the center of the insulating assembly 3 near the end close to the insulating medium 4.

[0022] Specifically, the insulating medium 4 is a ceramic material, and the insulating material 7 is in powder form. The insulating assembly 3 is made of an insulating material with a high relative permittivity. The insulating assembly 3 and the metal outer tube 5 are connected by insulating adhesive. The portion of the lead-out rod 2 inside the insulating assembly 3 and the portion away from the insulating assembly 3 and exposed to air are coated with an insulating layer 1, but the portion of the lead-out rod 2 near the heating wire 6 does not have an insulating layer 1.

[0023] During operation, the insulating assembly 3 increases the distance between the two lead-out rods 2 at its ends, thereby increasing the electrical clearance between them. Both the portions of the lead-out rods 2 extending out of the insulating assembly 3 and the internal portions of the insulating assembly 3 are coated with an insulating layer 1 to prevent exposed portions in the air, thus meeting the requirements for electrical safety distances. The insulating assembly 3 and the insulating medium 4 are connected using a raised-lower structure, and the connection is filled with sealant. The raised-lower structure increases the creepage distance between the lead-out rods 2 and between the lead-out rods 2 and the metal outer tube 5. The sealant is used to account for air gaps that could occur between the connection sections, affecting the service life of the electric heating tube 8. After the electric heating tube 8 is assembled, the insulating assembly 3 is higher than the metal outer tube 5, which reduces the difficulty of the manufacturing process and also increases the creepage distance.

[0024] This application meets the electrical clearance requirements under high-voltage conditions. The insulating medium 4 used in this application is made of high-dielectric-strength insulating material. The insulating assembly 3 has a certain angle to increase the distance between the two lead-out rods 2, and insulating material 7 is placed on the outside of the lead-out rods 2. Even when the lead-out rods 2 are in the air, the electrical clearance requirements are still met. It also meets the creepage requirements under high-voltage conditions. The manufacturing process is simplified, and the assembly can be manufactured separately. Furthermore, compared with low-voltage electric heaters, it saves on the power distribution costs of the electric heater system and improves the overall electrothermal conversion efficiency of the system.

[0025] Working Principle: The insulating assembly 3 increases the distance between the two lead-out rods 2 at the ends, thereby increasing the electrical clearance between them. Both the portions of the lead-out rods 2 extending out of the insulating assembly 3 and the internal portions of the assembly 3 are coated with an insulating layer 1 to prevent exposed parts in the air, meeting the requirements for electrical safety distances. The insulating assembly 3 and the insulating medium 4 are connected using a raised-lower structure, and the connection is filled with sealant. The raised-lower structure increases the creepage distance between the lead-out rods 2 and between the lead-out rods 2 and the metal outer tube 5. The sealant is used to account for air gaps that could affect the service life of the electric heating tube 8. After the electric heating tube 8 is assembled, the insulating assembly 3 is higher than the metal outer tube 5, which reduces the difficulty of the manufacturing process and also increases the creepage distance.

[0026] The terms "front," "back," "left," "right," "top," and "bottom" all refer to the figures in the accompanying drawings. Figure 1 Based on the perspective of the observer, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0027] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship 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. Therefore, they should not be construed as limiting the scope of protection of this utility model.

[0028] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A double-ended high-voltage heating tube end sealing structure, characterized in that: It includes an electric heating tube (8), which is composed of a metal outer tube (5), an electric heating wire (6) and a lead-out rod (2); The electric heating tube (8) is equipped with two symmetrically arranged electric heating wires (6) and two symmetrically arranged lead-out rods (2). The electric heating wires (6) are connected to the lead-out rods (2). An insulating assembly (3) is provided on the outside of the lead-out rods (2). An insulating medium (4) is filled between the electric heating wires (6) and the metal outer tube (5). An insulating material (7) is filled between the insulating medium (4) and the electric heating wires (6). The cross-section of the metal outer tube (5) is U-shaped.

2. The end sealing structure of a double-ended high-voltage heating tube according to claim 1, characterized in that: The two lead-out rods (2) have stepped sides. The two lead-out rods (2) are closer together when they are inside the insulating assembly (3), and the two lead-out rods (2) are closer together when they are outside the insulating assembly (3) than when they are inside the insulating assembly (3).

3. The end sealing structure of a double-ended high-voltage heating tube according to claim 1, characterized in that: Two grooves are provided at the port of the metal outer tube (5), and a groove is provided at the center of the insulating assembly (3) near one end of the metal outer tube (5).

4. The end sealing structure of a double-ended high-voltage heating tube according to claim 1, characterized in that: The insulating medium (4) is a ceramic material, and the insulating material (7) is in powder form.

5. The end sealing structure of a double-ended high-voltage heating tube according to claim 1, characterized in that: The insulating assembly (3) is made of an insulating material with a high relative permittivity.

6. The end sealing structure of a double-ended high-voltage heating tube according to claim 1, characterized in that: The insulating assembly (3) and the metal outer tube (5) are connected by insulating adhesive.

7. The end sealing structure of a double-ended high-voltage heating tube according to claim 1, characterized in that: The lead-out rod (2) is coated with an insulating layer (1) both inside the insulating assembly (3) and away from the insulating assembly (3) and in the air. The lead-out rod (2) near the electric heating wire (6) does not have an insulating layer (1).

Images