Tubular electric heater

Abstract

The utility model provides a tubular electric heater which is a result of comprehensive improvement and innovation of a traditional tubular resistance heater, a heating resistance wire is spirally sleeved on a ceramic insulation sheet outside a heating tube, and the electric power density of heating is improved; the heating pipe adopts an upgraded version made of the same material, so that the high-temperature resistance of the heating pipe can be improved, and the cost is only slightly increased; the proper insert is placed in the heating pipe, so that the heat transfer coefficient of the heating pipe and the gas in the pipe is greatly improved, and the total use length of the heating pipe is shortened; the overall structure of the heater is changed into a heat exchanger type with a cylindrical section from a cuboid structure, a plurality of groups of supporting plates used for supporting heating pipes are arranged in the heater, each group of supporting plates is composed of five supporting plates, and the supporting plates can be detached and can also be installed and fastened to form the whole supporting plate. The semicircular grooves matched with each other are formed between every two adjacent supporting plates, and the heating pipes are installed between the two semicircular grooves matched with each other, so that the heating pipes are convenient to assemble.

Description

Technical Field

[0001] The utility model relates to the technical field of heaters, in particular to a tubular electric heater. Background Art

[0002] At present, both at home and abroad, the heating of silicon tetrachloride gas adopts the method of placing a resistance heating component on one side of a gas flow pipeline for radiant heating. The heat generated by the traditional resistance heating component only radiantly heats the area where one side of the coil is located, and the heat on one side of the coil is then transferred to the entire cross-section of the coil through metal conduction. The surface temperature of the coil is extremely uneven, and after two heat transfers, the thermal efficiency is low, resulting in the need for a longer metal pipe for heat exchange under the condition of the same heat transfer; the utility model patent with the publication number of CN115962570A discloses a high-efficiency radiant tubular electric heater and its assembly method. In order to facilitate disassembly and assembly, the horizontal part and the bent part of the heat exchange pipeline are designed to be detachable. However, due to the existence of the support plate, the heating resistance wire and the insulating part need to be removed during the disassembly process, and the subsequent assembly process is troublesome and not firm, and it is easy to fall apart during transportation and operation. Content of the Utility Model

[0003] The purpose of the utility model is to provide a tubular electric heater, which can realize rapid disassembly and assembly during transportation and is safe and reliable during transportation.

[0004] The utility model provides a tubular electric heater, which includes an outer shell. A heat exchange pipeline is installed inside the outer shell. The heat exchange pipeline includes a plurality of heating pipes connected in sequence. A heating resistance wire is spirally wound outside the heating pipe, and an insulating sheet is installed between the heating resistance wire and the heating pipe; the heat exchange pipeline is installed inside the outer shell through a plurality of groups of support plates arranged along the length direction of the outer shell. The support plate includes a plurality of support plates spliced in sequence. A mutually matching semi-circular groove is formed between every two adjacent support plates, and the heating pipe is installed between two mutually matching semi-circular grooves.

[0005] Further, a heat insulation cushion layer is arranged in each semi-circular groove on the support plate.

[0006] Further, an air inlet and an air outlet communicated with the reactor are respectively arranged at the head and the tail of the heat exchange pipeline.

[0007] Further, every two adjacent support plates in the same support plate are connected by insertion.

[0008] Further, connecting plates are welded at the edges of every two adjacent support plates, and bolts are connected between two mutually corresponding connecting plates on two adjacent support plates.

[0009] Further, extension parts are provided on both the front and rear sides of the semi-circular groove on the support plate.

[0010] Further, a temperature measuring groove is formed on the outer side of the heating pipe, and a thermocouple is installed in the temperature measuring groove.

[0011] Further, an inner insert is provided inside the heating pipe.

[0012] Further, a heat preservation pipe is provided on the outer side of the heating pipe, and the heating resistance wire is coated between the heating pipe and the heat preservation pipe.

[0013] Further, the heat insulation cushion layer is made of asbestos material.

[0014] The beneficial effect of the technical solution of the present utility model compared with the prior art is as follows: In this technical solution, the heat exchange pipeline is erected inside the outer shell by using a plurality of assembled support plates. A semi-circular groove is formed between every two adjacent support plates, and after splicing, a complete circular groove is formed to clamp a plurality of heating pipes, realizing the fixation of the heating pipes. When disassembling, the heat exchange pipeline can be removed from the outer shell by simply disassembling the support plates in sequence, which is convenient for disassembly and assembly during transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0016] Figure 1 It is a schematic diagram of the overall structure of the present utility model;

[0017] Figure 2 For the present utility model Figure 1 It is an enlarged schematic diagram of the structure at A in the present utility model.

[0018] Figure 3 It is a sectional view of the heating pipe in the present utility model.

[0019] Figure 4 It is a schematic diagram of the installation structure of the insulating sheet on the outer side of the heating pipe in the present utility model.

[0020] Figure 5 It is a partial enlarged view of the installation structure of the insulating sheet on the outer side of the heating pipe in the present utility model.

[0021] Figure 6 It is a sectional view of the bent pipe part of the heating pipe in the present utility model.

[0022] Figure 7 This is a diagram showing the internal structure of the bent pipe part of the heating pipe of the present utility model.

[0023] Figure 8 This is a sectional view showing the installation structure of the thermocouple of the present utility model on the heating pipe.

[0024] Figure 9 This is a structure diagram showing the covering of the heating resistance wire of the present utility model outside the heating pipe.

[0025] Figure 10 This is a structure diagram showing the covering of the heat preservation pipe of the present utility model outside the heating pipe.

[0026] Figure 11 This is a diagram showing the layout structure of the heat preservation pipe on the heating pipe of the present utility model and the structural cooperation with the support plate.

[0027] Explanation of reference numerals: 1 - outer housing; 2 - end cover; 3 - support plate; 4 - heat exchange pipeline; 401 - heating pipe; 5 - air inlet; 6 - air outlet; 7 - connecting plate; 8 - bolt; 9 - nut; 10 - insulating sheet; 11 - heating resistance wire; 12 - heat preservation pipe; 13 - welded bent rod; 14 - inner insert; 15 - annular insulating sheet; 16 - thermocouple; 17 - insulating support sheet; 18 - temperature measuring groove; 19 - extension part; 20 - heat insulation cushion layer. Detailed implementation manners

[0028] Next, the technical solutions of the present utility model will be clearly and completely described in conjunction with the embodiments. Obviously, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts shall fall within the protection scope of the present utility model.

[0029] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present utility model.

[0030] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of the said features. In the description of the present utility model, "a plurality of" means two or more, unless otherwise specifically defined. In addition, the terms "mounted", "connected" and "joined" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0031] Embodiment 1

[0032] As Figures 1-5 shown, the present utility model provides a tubular electric heater, which includes an outer casing 1. End caps 2 are closed at both sides of the outer casing 1. A heat exchange pipe 4 is mounted on the outer casing 1 through a plurality of support plates arranged along the length direction of the outer casing 1. The material of the heat exchange pipe 4 is selected as Incoloy 802, and the high temperature resistance strength is more durable. An air inlet 5 and an air outlet 6 communicating with the reactor are respectively arranged at the head and tail ends of the heat exchange pipe 4. The heat exchange pipe 4 includes a plurality of heating pipes 401 connected in sequence. The plurality of heating pipes 401 connected in sequence reciprocate along the axis direction of the outer casing 1, and elbows are used for connection at the turning points. In this embodiment, the outer side of the heating pipe 401 can be provided with a plurality of heating segments. Each heating segment is separated by a support plate. A heating resistance wire 11 is spirally wound on the outer side of each heating segment of the heating pipe 401. The spiral winding of the heating resistance wire 11 can not only improve the heat transfer efficiency, but also improve the uniformity of heat transfer. At the same time, standby heating segments can be provided. During use, the heating segments can be controlled to be turned on at intervals. When a heating segment is damaged, it can be switched in time (for example, when there are 6 heating segments, the 1st, 3rd and 5th heating segments can be turned on. When the above heating segments fail, the 2nd, 4th and 6th heating segments can be controlled to be turned on). An insulating sheet 10 is mounted between the heating resistance wire 11 and the heating pipe 401. Cylindrical holes are opened at both side edges of the ceramic sheet. When fixing, the ceramic sheet is attached to the surface of the heating pipe 401, and then a welding bent rod 13 is inserted into the cylindrical hole. The outer end of the welding bent rod 13 is welded to the outer surface of the heating pipe 401 to fix the ceramic sheet; in this embodiment, the cross section of the ceramic sheet is arc-shaped, and three ceramic sheets arranged at equal intervals can be fixedly arranged along the circumference at the same position of the heating pipe 401 to reduce the material consumption of the ceramic sheet. An annular insulating sheet 15 is sleeved outside the insulating sheet 10 after winding. A heat preservation pipe 12 is arranged outside the heating pipe 401. The heating resistance wire 11 is covered between the heating pipe 401 and the heat preservation pipe 12. As Figure 3As shown, the insulating sheet 10 and the annular insulating sheet 15 are wrapped inside the heat preservation pipe 12. In this embodiment, both the insulating sheet 10 and the annular insulating sheet 15 are made of high-temperature resistant ceramic sheets. On the one hand, it realizes the heat preservation effect on the heating pipe 401. On the other hand, it can wrap the heating resistance wire 11, the insulating sheet 10, the annular insulating sheet 15 and the heating pipe 401 to form a whole, so as not to fall apart during transportation. As Figures 6-7 shown, an insulating support sheet 17 is provided between the heat preservation pipe 12 and the heating resistance wire 11 at the bent pipe part.

[0033] As Figures 9-11 shown, the heat preservation pipe 12 is wrapped around the outside of the heating pipe 401 in a segmented manner.

[0034] The support plate includes a plurality of support plates 3 spliced in sequence. The plurality of support plates 3 are assembled into a circular structure. Semi-circular grooves that cooperate with each other are provided between every two adjacent support plates 3. Two mutually cooperating semi-circular grooves are combined to form a circular groove hole. The heating pipe 401 is installed between two mutually cooperating semi-circular grooves. Extension parts 19 are provided on both the front and back sides of the semi-circular grooves on the support plate 3 to expand the support area for the heating pipe 401 and form good support for the heating pipe 401.

[0035] An insulating cushion layer 20 is provided in each semi-circular groove on the support plate 3. The insulating cushion layer 20 can be an asbestos blanket. Setting the insulating cushion layer can prevent the heat of the heating pipe 401 from being transferred to the support plate 3 and reduce the heat loss of the heating pipe 401 to a certain extent.

[0036] In the same support plate, every two adjacent support plates 3 are connected by plugging. The specific plugging connection structure is as follows: connecting plates 7 are welded to the edges of every two adjacent support plates 3. A bolt 8 is connected between two mutually corresponding connecting plates 7 on two adjacent support plates 3. When two adjacent support plates 3 are connected, they are connected by the cooperation of the bolt 8 and the nut 9.

[0037] In this technical solution, by designing the support plate 3 into an assembled structure, it not only provides reliable support, fixation and anti-vibration effects for the heating pipe 401 and each heating element surrounding them in segments, but also solves the problem of rapid replacement after the heating element is segmented and damaged.

[0038] As Figure 8 shown, a temperature measuring groove 18 is provided on the outside of the heating pipe 401. A thermocouple 16 is installed in the temperature measuring groove 18. The thermocouple 16 is used to measure the temperature of the heating pipe 401, and then control the heating power of the heating resistance wire 11 through the temperature data fed back by the thermocouple 16, so as to control the temperature of the gas to be heated.

[0039] In order to achieve uniform heating of the gas inside the heating pipe 401, an internal insert 14 is provided along the inside of the heating pipe 401. In the straight pipe part, the internal insert adopts the SK-type mixer unit structure internal insert 14, and in the bent pipe part, a large void fraction porous internal insert 14 is used, thereby greatly increasing the convective heat transfer coefficient of the gas inside the pipe, enabling the internal gas to effectively contact the inner wall of the heating pipe 401 and making the heating more sufficient.

[0040] The main function of this technical solution is to provide powerful high-power radiant heat per unit area to the outer wall of the heating pipe 401. In this design, two types of internal inserts, namely the SK-type mixer unit structure internal insert and the large void fraction porous internal insert, are used inside the heating pipe 401, thereby greatly increasing the convective heat transfer coefficient of the gas inside the pipe to improve the heat transfer speed.

[0041] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A tubular electric heater, characterized in that: It includes an outer shell, wherein a heat exchange pipe is installed inside the outer shell, and the heat exchange pipe includes a plurality of heating pipes connected in sequence, a heating resistance wire is spirally wound around the outer side of the heating pipe, and an insulating sheet is installed between the heating resistance wire and the heating pipe; the heat exchange pipe is installed inside the outer shell through a plurality of groups of support plates arranged along the length direction of the outer shell, the support plate includes a plurality of support plates spliced ​​in sequence, and mutually matching semicircular grooves are opened between every two adjacent support plates, and the heating pipe is installed between the two mutually matching semicircular grooves.

2. The tubular electric heater according to claim 1, characterized in that: A heat insulating pad is provided in each of the semicircular grooves on the support plate.

3. The tubular electric heater according to claim 1, characterized in that: The heat exchange pipe is provided with an air inlet and an air outlet at both ends thereof, which are connected with the reactor.

4. The tubular electric heater according to claim 1, characterized in that: Every two adjacent support plates in the same support plate are plug-connected.

5. The tubular electric heater according to claim 4, characterized in that: A connecting plate is welded to the edges of every two adjacent support plates, and bolts are connected between two corresponding connecting plates on two adjacent support plates.

6. The tubular electric heater according to claim 1, characterized in that: The support plate is provided with extension parts on both the front and rear sides of the semicircular groove.

7. The tubular electric heater according to claim 1, characterized in that: A temperature measuring groove is provided on the outer side of the heating tube, and a thermocouple is installed in the temperature measuring groove.

8. The tubular electric heater according to claim 1, characterized in that: An inner plug-in unit is arranged inside the heating tube.

9. The tubular electric heater according to claim 1, characterized in that: A heat preservation tube is arranged on the outer side of the heating tube, and the heating resistance wire is wrapped between the heating tube and the heat preservation tube.

10. A tubular electric heater according to claim 2, characterized in that: The heat insulation cushion layer is made of asbestos material.

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