Uniform-temperature electric heating rod

Abstract

The utility model relates to the technical field of electric heating, in particular to a uniform-temperature electric heating rod, which comprises a shell, a wound magnesium rod, a heating wire, a heating wire head connecting point, a heating wire tail connecting point, a tail sealing plate and two heater binding posts, and is characterized in that the shell comprises a hollow heating rod outer tube, a quartz insulating layer and a magnesium oxide insulating layer; the tail sealing plate is connected with the heating rod outer pipe, the quartz insulating layer is arranged on the inner side of the heating rod outer pipe, the magnesium oxide insulating layer is arranged on the face, away from the heating rod outer pipe, of the quartz insulating layer, the wound magnesium rod is arranged in the magnesium oxide insulating layer, and the heating wires are connected with corresponding heater binding posts and heating wire tail connecting points. In this way, the technical problems that in the prior art, when an existing electric heating rod is actually used, heat emitted by a heating wire material needs to be transmitted to the insulating material magnesium oxide powder firstly and then transmitted to the metal outer pipe, so that the heat transmission efficiency is low, and heating is uneven are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of electric heating, in particular to a temperature-averaging electric heating rod. Background Art

[0002] An electric heating rod is a device that uses electric energy for heating. It is usually made of metal material and has a resistance wire or electric heating core inside. When current flows through the resistance wire, it generates heat, thereby heating the surrounding objects. The electric heating rod has the characteristics of fast heating speed and high efficiency. It can quickly heat objects to the required temperature and is widely used in fields such as heating water.

[0003] However, when the existing electric heating rod is actually used, the heat generated by the heating wire material is first transferred to the insulating material magnesium oxide powder, and then to the metal outer tube, resulting in low heat transfer efficiency and uneven heating. Utility Model Content

[0004] The utility model aims to provide a uniform temperature electric heating rod, aiming to solve the technical problem that in the actual use of the existing electric heating rods in the prior art, the heat emitted by the heating wire material is first transferred to the insulating material magnesium oxide powder, and then to the metal outer tube, resulting in low heat transfer efficiency and uneven heating.

[0005] To achieve the above-mentioned purpose, the utility model adopts a temperature-averaging electric heating rod, including a shell, a wound magnesium rod, a heating wire, a heating wire head connection point, a heating wire tail connection point, a tail sealing plate and two heater terminals, the shell includes a heating rod outer tube, a quartz insulation layer and a magnesium oxide insulation layer, the heating rod outer tube is hollow, the tail sealing plate is connected to the heating rod outer tube, the quartz insulation layer is arranged on the inner side of the heating rod outer tube, the magnesium oxide insulation layer is arranged on the side of the quartz insulation layer away from the heating rod outer tube, the wound magnesium rod is placed in the magnesium oxide insulation layer, the heating wire head connection point and the heating wire tail connection point are both connected to the wound magnesium rod, the two heater terminals are respectively connected to the wound magnesium rod and the heating wire head connection point, the heating wire is wound on the wound magnesium rod, and the heating wire is connected to the corresponding heater terminal and the heating wire tail connection point.

[0006] The temperature-averaging electric heating rod further comprises a thermocouple lead, a temperature-measuring thermocouple and a temperature-measuring probe. The temperature-measuring probe is connected to the wound magnesium rod, and the temperature-measuring thermocouple is arranged between the thermocouple lead and the temperature-measuring probe.

[0007] The straight-line distance between the inner diameter of the magnesium oxide insulation layer and the outer diameter of the heating wire after winding is L1=1.8 mm.

[0008] The shell has a heating length and a tail cold section, the heating length is L2=206mm, and the tail cold section is L3=30mm.

[0009] The utility model discloses a temperature-averaging electric heating rod. When used, the blank tube material of the outer tube of the heating rod is a 25X2 Cr20Ni80 tube, which is shrunk to an outer diameter of 2.15±0.3, with plugs welded at both ends, and the outer circle is ground to match the hole after straightening. The heating wire is a 0.7mm nickel-chromium wire, and the outer diameter of the heating wire winding is φ17.4. After assembly, the gap between the magnesium oxide insulation layer and the heating wire is 1.8mm;

[0010] The use of the temperature-averaging electric heating rod of the utility model has the following beneficial effects: 1. The CNC wire winding equipment is used to make the spiral pitch of the heating wire winding equal, and the accuracy of the winding length is also guaranteed, so that the heating is uniform; 2. The insulating material magnesium oxide powder between the metal sleeve and the spiral heating wire is replaced by a customized quartz sleeve, which avoids the unevenness and looseness of the magnesium oxide powder filled, and the thickness of the insulation layer is maintained at 1mm; 3. The outer diameter of the component is externally ground, so that the outer diameter tolerance accuracy is controlled at ±0.05mm, and the clearance with the inner hole of the user's equipment is smaller, so that the heat is better transferred to the outside;

[0011] Through the power-on test, when the outer tube surface temperature of the heating rod is in the insulation state of 900°C, the inner core temperature of the heating rod is 977°C, and the temperature difference is 77°C. There is still more than 100 degrees of space from the use limit temperature of 1100°C of the heating wire, which can ensure the service life of the temperature-averaging heating rod;

[0012] In this way, the technical problem that the heat generated by the heating wire material of the existing electric heating rod in the prior art is first transferred to the insulating material magnesium oxide powder and then to the metal outer tube during actual use, resulting in low heat transfer efficiency and uneven heating is solved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0014] Figure 1 It is a structural schematic diagram of the temperature-averaging electric heating rod of the utility model.

[0015] Figure 2 It is a partial structural schematic diagram of the temperature-averaging electric heating rod of the utility model.

[0016] Figure 3It is a cross-sectional view of the temperature-averaging electric heating rod of the utility model.

[0017] 1- wound magnesium rod, 2- heating wire, 3- heating wire head connection point, 4- heating wire tail connection point, 5- tail sealing plate, 6- heater terminal, 7- heating rod outer tube, 8- quartz insulation layer, 9- magnesium oxide insulation layer, 10- thermocouple lead, 11- temperature measuring thermocouple, 12- temperature measuring probe. DETAILED DESCRIPTION

[0018] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0019] See also Figures 1 to 3 , Figure 1 This is a structural schematic diagram of the temperature-averaging electric heating rod of the utility model. Figure 2 This is a partial structural diagram of the temperature-averaging electric heating rod of the utility model. Figure 3 The utility model provides a temperature-averaging electric heating rod: comprising a shell, a wound magnesium rod 1, a heating wire 2, a heating wire head connection point 3, a heating wire tail connection point 4, a tail sealing plate 5 and two heater terminals 6, the shell comprising a heating rod outer tube 7, a quartz insulating layer 8 and a magnesium oxide insulating layer 9, the heating rod outer tube 7 is hollow, the tail sealing plate 5 is connected to the heating rod outer tube 7, the quartz insulating layer 8 is arranged on the inner side of the heating rod outer tube 7, the magnesium oxide insulating layer 9 is provided on the inner side of the heating rod outer tube 7, and the magnesium oxide insulating layer 9 is provided on the inner side of the heating rod outer tube 7. The magnesium insulating layer 9 is arranged on a side of the quartz insulating layer 8 away from the outer tube 7 of the heating rod, the wound magnesium rod 1 is placed in the magnesium oxide insulating layer 9, the heating wire head connection point 3 and the tail connection point of the heating wire 2 are both connected to the wound magnesium rod 1, the two heater terminals 6 are respectively connected to the wound magnesium rod 1 and the heating wire head connection point 3, the heating wire 2 is wound on the wound magnesium rod 1, and the heating wire 2 is connected to the corresponding heater terminal 6 and the tail connection point of the heating wire 2;

[0020] The straight-line distance between the inner diameter of the magnesium oxide insulating layer 9 and the outer diameter of the heating wire 2 after winding is L1=1.8 mm.

[0021] The shell has a heating length and a tail cold section, the heating length is L2=206mm, and the tail cold section is L3=30mm.

[0022] In this embodiment, when used, the blank tube material of the outer tube 7 of the heating rod is a 25X2 Cr20Ni80 tube, which is shrunk to an outer diameter of 2.15±0.3, with plugs welded at both ends, and the outer circle is ground to match the hole after straightening. The heating wire 2 is a 0.7mm nickel-chromium wire, and the outer diameter of the winding of the heating wire 2 is φ17.4. After assembly, the gap between the magnesium oxide insulating layer 9 and the heating wire 2 is 1.8mm;

[0023] The use of the temperature-averaging electric heating rod of the utility model has the following beneficial effects: 1. The CNC wire winding equipment is used to make the spiral pitch of the heating wire 2 equal, and the accuracy of the winding length is also guaranteed, so that the heating is uniform; 2. The insulating material magnesium oxide powder between the metal sleeve and the spiral heating wire 2 is replaced by a customized quartz sleeve, which avoids the unevenness and looseness of the magnesium oxide powder, and keeps the thickness of the insulation layer at 1mm; 3. The outer diameter of the component is externally ground, so that the outer diameter tolerance accuracy is controlled at ±0.05mm, and the clearance with the inner hole of the user's equipment is smaller, so that the heat is better transferred to the outside;

[0024] Through the power-on test, when the surface temperature of the outer tube 7 of the heating rod is 900°C in the insulation state, the temperature of the inner core of the heating rod is 977°C, and the temperature difference is 77°C. There is still more than 100 degrees of space from the use limit temperature of the heating wire of 21100°C, which can ensure the service life of the temperature-averaging heating rod;

[0025] In this way, the technical problem that the heat generated by the heating wire 2 material is first transferred to the insulating material magnesium oxide powder and then to the metal outer tube during actual use of the existing electric heating rod in the prior art is solved, resulting in low heat transfer efficiency and uneven heating.

[0026] Furthermore, the temperature-averaging electric heating rod also includes a thermocouple lead 10 , a temperature measuring thermocouple 11 and a temperature measuring probe 12 . The temperature measuring probe 12 is connected to the wound magnesium rod 1 , and the temperature measuring thermocouple 11 is arranged between the thermocouple lead 10 and the temperature measuring probe 12 .

[0027] In this embodiment, the temperature of the heating wire 2 is measured by the thermocouple lead 10 , the temperature measuring thermocouple 11 and the temperature measuring probe 12 , so that the temperature difference between the surface of the heating rod outer tube 7 and the heating wire 2 can be measured.

[0028] The beneficial effects of the utility model are as follows: 1. The CNC wire winding equipment is used to make the spiral pitch of the heating wire 2 equal, and the accuracy of the winding length is guaranteed, so that the heating is uniform; 2. The insulating material magnesium oxide powder between the metal sleeve and the spiral heating wire 2 is replaced by a customized quartz sleeve, so as to avoid the unevenness and looseness of the filling magnesium oxide powder, and keep the thickness of the insulation layer at 1mm; 3. The outer diameter of the component is ground externally, so that the outer diameter tolerance accuracy is controlled at ±0.05mm, and the clearance with the inner hole of the user's equipment is smaller, so that the heat is better transferred to the outside.

[0029] The above disclosure is only a preferred embodiment of the present invention, and certainly cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiment and equivalent changes made according to the claims of the present invention still fall within the scope covered by the utility model.

Claims

1. A temperature-uniform electric heating rod, characterized in that: It includes a shell, a wound magnesium rod, a heating wire, a heating wire head connection point, a heating wire tail connection point, a tail sealing plate and two heater terminals. The shell includes a heating rod outer tube, a quartz insulation layer and a magnesium oxide insulation layer. The heating rod outer tube is hollow. The tail sealing plate is connected to the heating rod outer tube. The quartz insulation layer is arranged on the inner side of the heating rod outer tube. The magnesium oxide insulation layer is arranged on the side of the quartz insulation layer away from the heating rod outer tube. The wound magnesium rod is placed in the magnesium oxide insulation layer. The heating wire head connection point and the heating wire tail connection point are both connected to the wound magnesium rod. The two heater terminals are respectively connected to the wound magnesium rod and the heating wire head connection point. The heating wire is wound on the wound magnesium rod, and the heating wire is connected to the corresponding heater terminal and the heating wire tail connection point.

2. The temperature-averaging electric heating rod according to claim 1, characterized in that: The temperature-averaging electric heating rod further comprises a thermocouple lead wire, a temperature-measuring thermocouple and a temperature-measuring probe. The temperature-measuring probe is connected to the wound magnesium rod, and the temperature-measuring thermocouple is arranged between the thermocouple lead wire and the temperature-measuring probe.

3. The temperature-averaging electric heating rod according to claim 2, characterized in that: The straight-line distance between the inner diameter of the magnesium oxide insulating layer and the outer diameter of the heating wire after winding is L1=1.8 mm.

4. The temperature-averaging electric heating rod according to claim 3, characterized in that: The shell has a heating length and a tail cold section, the heating length is L2=206mm, and the tail cold section is L3=30mm.

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