TWI821622B - Electric heating device and heat treatment furnace equipped with it - Google Patents

Abstract

The electric heating device installed on the furnace inner wall of the heat treatment furnace includes: a rod-shaped rod; a rod support portion for supporting the end of the rod on the furnace inner wall; a plurality of hooks suspended from the rod; and an electric heater, The hook is supported on a plurality of hooks.

Description

Electric heating device and heat treatment furnace equipped with it

Field of invention

The present disclosure relates to an electric heating device installed on the inner wall of a heat treatment furnace and a heat treatment furnace equipped with the electric heating device.

Background of the invention

In conventional electric heat treatment furnaces, such as Patent Document 1 and Patent Document 2, the corrugated upper part of a linear or flat heating element bent into a corrugated shape is hung on a hanger (nail or hook) in the furnace. Come hang. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Utility Model Publication No. Sho 62-163895 [Patent Document 2] Japanese Utility Model Publication No. Sho 60-45367 [Patent Document 3] Japanese Patent Application Publication No. 2009-250548 [Patent Document 4] Japanese Patent Application Publication No. 6-221770 [Patent Document 5] Japanese Patent Application Publication No. 2005-282928 [Patent Document 6] Japanese Patent Application Publication No. Sho 60-56025

[Summary of the invention] [Problem to be solved by the invention]

However, since the heating element is subject to thermal deformation, it must be suspended at all points to secure its position. Therefore, it takes a lot of time and effort to install a large number of hangers inside the furnace and suspend the heating elements.

In addition, although the furnace body is also cylindrical, as in Patent Document 3, the heater is suspended over the entire circumference of the inner wall of the furnace.

In addition, as in Patent Document 4 and Patent Document 5, when the furnace wall is made of ceramic fiber, the hanger is usually inserted and held therebetween, but there is a possibility of falling due to its own weight. On the other hand, as in Patent Document 6, there is also a case where the device is inserted into a metal frame protruding from the periphery. However, since the hanger is inserted horizontally, there is still a risk of falling off after years of use.

The purpose of this disclosure is to solve the above-mentioned problems and provide an electric heating device that can be easily installed and a heat treatment furnace equipped with the same. [Means used to solve problems]

One aspect of the electric heating device disclosed in the present disclosure is an electric heating device installed on the inner wall of the furnace of a heat treatment furnace, and includes: a rod; a rod support portion used to support the end of the rod with the inner wall of the furnace; and a plurality of hooks. Suspended from the aforementioned rod; and the electric heater is hooked and supported on the aforementioned plurality of hooks.

According to the above structure, by carrying the electric heater into the heat treatment furnace in a state of being hooked on a plurality of hooks suspended from the rod, the electric heating device can be installed in the furnace simply by placing the rod on the rod support. on the medial wall. By doing this, the assembly work of the heater outside the furnace and the arrangement work of the heater inside the furnace can be performed simultaneously, and the construction period can be shortened. In addition, the working time in a furnace operating at high altitudes can be shortened, and the risk of dangerous work can also be reduced.

In the electric heating device, the rod support portion may be detachable from the barrel portion of the furnace inner wall. According to the above-mentioned structure, the replacement or repair of the rod support part is easy.

In the electric heating device, the rod support portion may be configured to protrude upward from the horizontal direction and toward the inside of the heat treatment furnace while being disposed on the cylindrical portion. According to the above-mentioned structure, the rod support part is difficult to fall off from the tube part.

The electric heating device may further include an electrode protruding from the furnace inner wall at a position lower than the rod support portion and connected to an end of the electric heater, and the electric heater is arranged along the rod. The upper surface of the support part is hooked and extends downward toward the electrode. According to the above configuration, compared with when the end portion of the electric heating heater is extended in the horizontal direction and connected to the electrode, the stress generated in the end portion can be reduced, and the end portion of the electric heating heater can be connected with high accuracy. to the electrode.

In the electric heating device, the furnace inner wall may be rectangular in plan view, and the rod may have a linearly extending shape and may be arranged along the furnace inner wall. According to the above-described configuration, a rod made of a general-purpose member can be used.

In the electric heating device, the furnace inner wall may be circular in plan view, and the rod may have a shape extending in an arc shape and may be arranged along the furnace inner wall. According to the aforementioned structure, even when the furnace inner wall has a circular cross-section, the electric heating device can be arranged corresponding to the shape of the furnace inner wall.

A heat treatment furnace according to one aspect of the present disclosure includes: the aforementioned electric heating device; and the aforementioned furnace inner wall on which the aforementioned electric heating device is installed.

According to the aforementioned structure, the same effect as the aforementioned electric heating device can be achieved. [Effects of the invention]

According to the present disclosure, the installation work of the electric heating device can be easily performed.

[Form used to implement the invention]

Hereinafter, suitable embodiments of the electric heating device and the heat treatment furnace equipped with the same will be described with reference to the drawings. This disclosure is not limited to the specific configurations of the following embodiments, and configurations based on the same technical ideas are included in this disclosure.

(Embodiment 1) FIG. 1 is a plan view showing the schematic structure of the heat treatment furnace 2 in Embodiment 1.

The heat treatment furnace 2 is a furnace body for accommodating the object to be heated 6 and heating it. The heat treatment furnace 2 of Embodiment 1 particularly uses an electric heater as a heating means, and indirectly heats the object 6 from the outside of the muffle furnace 8 while the object 6 is accommodated in the muffle furnace 8 . As shown in FIG. 1 , the heat treatment furnace 2 includes a furnace wall 4 , a muffle furnace 8 that houses an object to be heated 6 , and a plurality of electric heating devices 10 .

The furnace wall 4 is a member constituting the outer periphery of the heat treatment furnace 2 . The furnace wall 4 is made of an insulating material such as a brick or a ceramic fiber plate. The side inside the furnace wall 4 is the furnace inner wall 5 . The furnace inner wall 5 in Embodiment 1 is formed into a rectangular shape in plan view.

The muffle furnace 8 is a member that accommodates the object 6 to be heated. The object 6 to be heated is, for example, a steel belt, and is conveyed in a direction perpendicular to the paper surface. The muffle furnace 8 in Embodiment 1 is cylindrical.

The internal space S1 of the muffle furnace 8 is sealed with respect to the external space S2 of the muffle furnace 8 , that is, with respect to the space surrounded by the muffle furnace 8 and the furnace inner wall 5 . While the external space S2 of the muffle furnace 8 is open to the atmosphere, the internal space S1 of the muffle furnace 8 is filled with a gas different from the atmosphere (for example, nitrogen). The internal space S1 of the muffle furnace 8 is in a positive pressure state so that the atmosphere does not flow in from the external space S2.

The electric heating device 10 is an electric heating device that indirectly heats the object 6 in the internal space S1 of the muffle furnace 8 . The electric heating device 10 is located in the external space S2 of the muffle furnace 8 and is installed on the inner wall 5 of the furnace.

The electric heating device 10 in Embodiment 1 is installed on each surface of the furnace inner wall 5, and as shown in FIG. 8, a plurality of stages are arranged in the upper and lower furnace length directions. The electrothermal heating devices 10 each have the same configuration.

The detailed structure of the electrothermal heating device 10 will be described using FIGS. 2 to 6 . FIG. 2 is an enlarged view of a part of FIG. 1 , and is a plan view showing the electric heating device 10 and its surroundings. FIG. 3 is a perspective view of the electrothermal heating device 10 , and FIG. 4 is a front view of the electrothermal heating device 10 . FIG. 5 is a longitudinal sectional view showing the rod support portion 14 of the electrothermal heating device 10 and its surroundings. FIG. 6 is a longitudinal sectional view showing the hook 16 of the electrothermal heating device 10 and its surroundings.

As shown in FIGS. 2 to 4 , the electric heating device 10 includes a rod 12 , a rod support part 14 ( FIGS. 2 and 4 ), a plurality of hooks 16 and an electric heater 18 .

Rod 12 is a rod-shaped member. The rod 12 is not limited to a rod shape with a circular cross section, and may be in any shape such as a flat plate shape with a rectangular cross section. The rod 12 in Embodiment 1 extends in a straight line and has a hollow cylindrical shape. The material of the rod 12 is an insulating material such as ceramics. The rod 12 is supported by a rod support 14 .

The rod support part 14 is a member for supporting the rod 12 on the furnace inner wall 5 . Two rod support portions 14 are provided to support both ends of the rod 12 . The rod support portion 14 is made of an insulating member such as bricks.

The rod support part 14 is detachable from the cylindrical part 20 provided in the furnace inner wall 5. The cylinder part 20 is reinforced with a triangular plate 21 (Fig. 2) and welded to the furnace inner wall 5. 2 and 5 show the state in which the rod support part 14 is inserted into the cylinder part 20 of the furnace inner wall 5.

As shown in FIG. 5 , the rod support portion 14 extends in the direction A into the internal space of the heat treatment furnace 2 in a state of being inserted into the cylinder portion 20 . The A direction in which the rod support portion 14 extends upward with respect to the horizontal direction H corresponds to an angle θ. Angle θ is an acute angle.

The rod support 14 has a recess 15 at its front end. The recessed portion 15 is a portion that receives the rod 12 and is formed on the upper surface of the rod support portion 14 . Both ends of the rod 12 are arranged in the recessed portion 15 of the rod support portion 14 , and the rod 12 is supported by the rod support portion 14 .

Returning to FIGS. 2 to 4 , the hook 16 is suspended from the rod 12 and is used to hook the member supporting the electric heater 18 . A plurality of hooks 16 are provided according to the waveform shape of the electric heater 18 . The hook 16 in Embodiment 1 has a ring shape, and the rod 12 passes through the ring of the hook 16 . The shape of the hook 16 is not limited to a ring shape, and other shapes such as an S shape may be used as long as the electric heater 18 can be suspended from the rod 12 and supported.

As shown in FIG. 6 , the hook 16 in Embodiment 1 includes a body portion 30 , a shaft portion 32 , and a ceramic stopper 34 . The body portion 30 is a portion that engages with the rod 12 and is suspended from the rod 12 . The shaft part 32 is a part welded to the main body part 30 after passing through the hole of the stopper 34, and has an annular shape together with the main body part 30. The barrier 34 is provided with a groove, and the groove supports the corrugated upper end of the electric heater 18 from below.

The electric heater 18 can be easily disposed in the loop of the hook 16 by sequentially passing the loop-shaped hook 16 from the end of the electric heater 18 .

The electric heater 18 is an electric heater for heating the object 6 . The electric heater 18 in Embodiment 1 is a heating wire and is in the shape of a rod (line) made of metal (for example, a nickel-chromium wire). As shown in FIGS. 3 and 4 , the electric heater 18 has a corrugated shape, and its upper end portions, which are folded portions, are respectively hooked on the hooks 16 . The electric heater 18 is not limited to a rod shape, and may also be in a flat strip shape.

As shown in FIGS. 4 and 5 , both ends of the electric heater 18 are connected (for example, welded) to the electrode 22 . The electrode 22 is a metal member for energizing the electric heater 18 and protrudes from the outside of the heat treatment furnace 2 through the furnace wall 4 into the inside of the heat treatment furnace 2 . The electrode 22 is disposed below the cylindrical portion 20 in which the rod support portion 14 is disposed.

As shown in FIGS. 4 and 5 , both ends of the electric heater 18 are arranged to be hooked on the upper surface of the rod support 14 and extend downward, and are connected to the electrodes 22 . With such an arrangement, the stress exerted on both ends of the electrothermal heater 18 becomes smaller compared to the case where both ends of the electrothermal heater 18 extend in the horizontal direction and are connected to the electrode 22 . Furthermore, both ends of the electric heater 18 may be wound around the front end of the rod support 14 .

As described above, the electric heating device 10 of Embodiment 1 is installed on the furnace inner wall 5 of the heat treatment furnace 2 and has: a rod 12; a rod support portion 14 for supporting the end of the rod 12 with the furnace inner wall 5; A plurality of hooks 16 are suspended from the rod 12, and an electric heater 18 is hooked and supported on the plurality of hooks 16.

According to this configuration, by carrying the electric heater 18 into the heat treatment furnace 2 with the electric heater 18 hooked on the plurality of hooks 16 suspended from the rod 12, the rod 12 can be placed on the rod support portion 14. The electric heating device 10 is installed on the inner wall 5 of the furnace. By doing this, the assembly work of the electric heating device 10 outside the furnace and the arrangement work of the electric heating device 10 inside the furnace can be performed simultaneously, and the construction period can be shortened. In addition, the working time in a furnace operating at high altitudes can be shortened, and the risk of dangerous work can also be reduced. After doing so, the installation work of the electric heating device 10 can be easily performed. In addition, by supporting the electric heater 18 on the rod 12 through the plurality of hooks 16, the heat of the electric heater 18 is not directly transmitted to the rod 12, so thermal damage to the rod 12 can be suppressed. Thereby, the heat-resistant life of the rod 12 and the electric heating device 10 can be extended.

Moreover, according to the electric heating device 10 of Embodiment 1, the rod support part 14 is detachable from the cylindrical part 20 of the furnace inner wall 5. With such a structure, the rod support part 14 can be easily replaced or repaired.

Furthermore, according to the electrothermal heating device 10 of Embodiment 1, the rod support portion 14 protrudes upwards from the horizontal direction H and into the inside of the heat treatment furnace 2 while being disposed in the cylinder portion 20 . According to such a structure, the rod support part 14 can be made difficult to fall off from the cylindrical part 20.

Furthermore, the electrothermal heating device 10 of Embodiment 1 further includes an electrode 22 protruding from the furnace inner wall 5 at a position below the rod support 14 and connected to the end of the electrothermal heater 18 . The electric heater 18 is arranged to be hooked along the upper surface of the rod support 14 and extend downward toward the electrode 22 . According to such a configuration, compared with the case where the end portion of the electrothermal heater 18 extends in the horizontal direction and is connected to the electrode 22, the stress generated in the end portion can be reduced, and deformation and deformation of the end portion can be suppressed. damage. Thereby, the electric heater 18 can be connected to the electrode 22 with high precision.

Furthermore, according to the electric heating device 10 of Embodiment 1, the furnace inner wall 5 is rectangular in plan view, and the rod 12 has a linearly extending shape and is arranged along the linear furnace inner wall 5 . According to such a configuration, the rod 12 of a common member can be used, and the manufacturing cost of the electrothermal heating device 10 can be reduced.

Moreover, the heat treatment furnace 2 of Embodiment 1 is provided with the electrothermal heating device 10 mentioned above, and the furnace inner wall 5 to which the electrothermal heating device 10 is mounted. According to such a structure, the same effect as that of the electrothermal heating device 10 described above can be achieved.

The invention of the present disclosure has been described above with reference to the first embodiment, but the invention of the present disclosure is not limited to the first embodiment. For example, in the above-mentioned Embodiment 1, the case where the rod support part 14 of the support rod 12 is detachable from the cylinder part 20 of the furnace inner wall 5 has been described, but it is not limited to this case. For example, like the heat treatment furnace 100 shown in FIG. 7 , a through hole 104 can be provided in the furnace wall 102 , and the electric heating device 106 can be installed by inserting the rod 108 of the electric heating device 106 into the through hole 104 . Furnace wall 102. According to such a structure, the rod support part 14 like Embodiment 1 can be omitted, and the electrothermal heating device 106 can be supported on the furnace wall 102, and a structure can be simplified. Furthermore, in the modification shown in FIG. 7 , the through hole 104 provided in the furnace wall 102 functions as a "rod support part." The gap between the through hole 104 and the rod 108 is additionally filled with an insulating material or the like and closed.

Moreover, in the above-mentioned Embodiment 1, the case where the furnace inner wall 5 is rectangular in plan view has been described, but it is not limited to this case, and may be, for example, circular as shown in FIG. 9 . In this case, a gently curved rod may be used instead of the linear rod 12 . In the heat treatment furnace 200 shown in FIG. 9 , the furnace wall 204 is formed in an arc shape, and the furnace inner wall 205 has a circular cross-sectional shape. The rod 212 of the electric heating device 210 extends in an arc shape and is arranged along the inner wall 205 of the furnace. The rod 212 is supported by the first rod support part 214A and the second rod support part 214B. The first rod support part 214A is a brick support that supports the two adjacent end parts of the two rods 212, and the second rod support part 214B is a brick support that supports the middle part of the one rod 212. By using the first rod support portion 214A for the two rods 212, an efficient structure can be achieved. Furthermore, by providing the second rod support part 214B in addition to the first rod support part 214A, compared with a configuration in which both ends of the rod 212 are supported only by the first rod support part 214A, it is possible to support the rod 212 while restricting its rotation. Rod 212 can be stably supported.

Furthermore, by appropriately combining any of the above various embodiments, the respective effects can be achieved.

Although this disclosure fully describes ideal embodiments with reference to the drawings, various modifications and variations will be obvious to those skilled in the art. Such deformations and modifications should be understood to be included as long as they do not exceed the scope of the present disclosure based on the appended claims. In addition, the combination of the elements in each embodiment or the change of the order can be realized without departing from the scope and idea of this disclosure. [Industrial availability]

As long as the electric heating device is installed on the inner wall of the heat treatment furnace and the heat treatment furnace equipped with it, this disclosure can be applied.

2:Heat treatment furnace 4: Furnace wall 5: Furnace inner wall 6: Heated object 8:Muffle furnace 10: Electric heating device 12: Rod 14: Rod support part 15: concave part 16:hook 18:Electric heater 20: Barrel part 21:triangular plate 22:Electrode 30: Ontology part 32: Loading and unloading part, shaft part 34: Support part, barrier 100:Heat treatment furnace 102: Furnace wall 104:Through hole 106: Electric heating device 108: Rod 200:Heat treatment furnace 204:furnace wall 205: Furnace inner wall 210: Electric heating device 212:rod 214A: 1st rod support part 214B: 2nd rod support part S1: Internal space of muffle furnace S2: External space of muffle furnace A: The direction in which the rod support extends H: horizontal direction θ: angle

Fig. 1 is a plan view showing the schematic structure of a heat treatment furnace in Embodiment 1. FIG. 2 is a plan view showing the electrothermal heating device in Embodiment 1. FIG. FIG. 3 is a perspective view showing the electrothermal heating device in Embodiment 1. FIG. FIG. 4 is a front view showing the electrothermal heating device in Embodiment 1. FIG. 5 is a longitudinal sectional view showing the rod support portion and its surroundings of the electrothermal heating device in Embodiment 1. 6 is a longitudinal sectional view showing the hook of the electrothermal heating device in Embodiment 1 and its surroundings. FIG. 7 is a plan view showing the schematic structure of a heat treatment furnace in a modified example. FIG. 8 is a schematic diagram showing an actual use example of the electrothermal heating device in Embodiment 1. FIG. FIG. 9 is a plan view showing the schematic structure of a heat treatment furnace in another modified example.

10: Electric heating device

12: Rod

14: Rod support part

16:hook

18:Electric heater

22:Electrode

Claims (7)

An electric heating device is an electric heating device installed on the inner wall of a heat treatment furnace and has: rod; rod A rod support portion protrudes toward the inside of the furnace from the inner wall of the furnace in order to support the end of the rod; a plurality of hooks suspended from said rods; and The electric heater is hooked and supported on the plurality of hooks mentioned above. The electric heating device of claim 1, wherein the rod support part is removable from the barrel part of the inner wall of the furnace. The electric heating device according to claim 2, wherein the rod support portion is formed to project upward from the horizontal direction and toward the inside of the heat treatment furnace when disposed in the cylinder portion. The electric heating device of Claim 1, further comprising: an electrode protruding from the inner wall of the furnace at a position lower than the rod support portion and connected to the end of the electric heater, The electric heater is arranged to be hooked along the upper surface of the rod support portion and extend downward toward the electrode. The electric heating device of claim 1, wherein the inner wall of the furnace is rectangular in plan view, The rod has a linearly extending shape and is arranged along the furnace inner wall. The electric heating device of claim 1, wherein the inner wall of the furnace is circular in plan view, The rod has a shape extending in an arc shape and is arranged along the inner wall of the furnace. A heat treatment furnace equipped with: Such as the aforementioned electric heating device in any one of claims 1 to 6; and The aforementioned electric heating device is installed on the inner wall of the aforementioned furnace.