Seal device for walking beam industrial furnace

Abstract

To provide a seal device for a walking beam industrial furnace that is excellent in sealing performance so as to prevent a dew point in the furnace from being increased and fire from being generated.SOLUTION: There is provided a device for sealing a moving post 55 of which an upper end part is fixed on a moving beam 53 for transporting material W to be processed inside a furnace body 51, of which a lower end part is fixed on a driving frame 54 driven by a lifting cylinder 56 and a reciprocal cylinder 57 on the outside thereof, and which is inserted into an insertion opening H formed on a furnace wall structure 52, the device being provided with a dry sealing structure 10 and a liquid sealing structure 20. The dry sealing structure 10 is configured to have material for sealing the insertion opening H to shutdown heat inside the furnace body 51. The liquid sealing structure 20 is configured to have a seal liquid 23 arranged below the dry sealing structure 10 and causing a lower part of the moving post 55 to be immersed and a seal cylindrical plate 21 surrounding a whole perimeter of the moving post at a lower side of the furnace wall structure 52 and causing a lower part thereof to be immersed in the seal liquid 23.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a sealing structure for sealing a moving post that supports from below a walking beam of an industrial furnace (such as a heat treatment furnace or a heating furnace) that employs a walking beam transportation system. [Background technology]

[0002] Industrial furnaces have traditionally been used to heat-treat steel-based materials (materials to be treated) to decarburize and prevent oxidation, and one such industrial furnace is the walking beam type. Generally, industrial furnaces of this type are of the roller hearth type or tray pusher type, but in the case of the walking beam type, which can transport materials one by one, it is necessary to support the moving beam, which moves in a rectangular shape up and down and back and forth inside the furnace body, from below and to seal the post that moves with the moving beam. This is to prevent gas inside the furnace body from leaking out through the opening formed in the hearth to allow the moving post to pass through.

[0003] As a means for sealing such a moving post, a water-sealed seal structure using water is known (see, for example, Patent Document 1).

[0004] 6, the water-sealed seal structure described in Patent Document 1 has a trough tank T filled with water L provided directly below an opening S formed in the hearth to insert a post P, and the lower end of a seal box B suspended from the periphery of the opening of the hearth is positioned in the water L. This prevents gas from leaking out of the furnace body. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2002-294332 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, the water-sealed seal structure described in Patent Document 1 has a problem in that water evaporates, raising the dew point inside the furnace body, which has an adverse effect on heat treatment. In view of these points, it is conceivable to use fire-retardant oil instead of water, but in that case, the high temperature inside the furnace body would directly act on the fire-retardant oil, causing a problem of flames being generated.

[0007] Therefore, an object of the present invention is to provide a sealing device for a walking beam type industrial furnace which has excellent sealing properties, does not raise the dew point inside the furnace body, and does not generate flames. [Means for solving the problem]

[0008] In order to achieve the above object, the sealing device (1) of the walking beam type industrial furnace of the present invention is a device for sealing a moving post (55) which has an upper end fixed to a moving beam (53) which transports a material (W) to be treated inside a furnace body (51) and a lower end fixed to a drive frame (54) which is driven by a lifting cylinder (56) and a forward / backward cylinder (57) outside the furnace body (51), and which is inserted into an insertion opening (H) formed in a furnace wall structure (52) including at least the hearth (51a) of the furnace body (51), The device has a dry seal structure (10) and a liquid seal structure (20), The dry seal structure (10), The insertion opening (H) is closed by a member that blocks heat inside the furnace body (51), The liquid seal structure (20), The sealing liquid (23) is provided below the dry seal structure (10) and at least the lower end of the movable post (55) is immersed in the sealing liquid (23), and a sealing cylinder plate (21) surrounds the entire circumference of the movable post (55) below the furnace wall structure (52) and has its lower part immersed in the sealing liquid (23), thereby preventing leakage of gas inside the furnace body (51).

[0009] The sealing device (1) for a walking beam type industrial furnace of the present invention is a device for sealing a moving post (55) which has an upper end fixed to a moving beam (53) for transporting a material (W) to be treated inside a furnace body (51) and a lower end fixed to a drive frame (54) which is driven by a lifting cylinder (56) and a forward / backward cylinder (57) outside the furnace body (51) and which is inserted into an insertion opening (H) formed in a furnace wall structure (52) including at least a hearth (51a) of the furnace body (51), The device has a dry seal structure (10) and a liquid seal structure (20), The dry seal structure (10), a slide seal plate (11) having a hole (11a) at a substantially central portion thereof through which the movable post (55) passes, the slide seal plate (11) being provided on the furnace wall structure (52) so as to move in the left-right direction together with the movable post (55), and having a size large enough to close the insertion opening (H); a packing (12) arranged to seal between the outer periphery of the moving post (55) and the hole (11a) of the slide seal plate (11); The liquid seal structure (20), a cylindrical seal cylinder plate (21) suspended from a portion surrounding the entire circumference of the insertion opening (H) on the lower surface of the furnace wall structure (52) so as to surround the entire circumference of the moving post (55); The sealing cylinder (21) is provided below the driving frame (54), and is characterized by being composed of a substantially box-shaped trough (22) filled with sealing liquid (23) in which at least the lower end of the sealing cylinder (21) is immersed.

[0010] Furthermore, the sealing device (1) for a walking beam type industrial furnace of the present invention is characterized in that the sealing liquid (23) is water.

[0011] Furthermore, the sealing device (1) for a walking beam type industrial furnace of the present invention is characterized in that the sealing liquid (23) is a non-flammable oil.

[0012] Here, the symbols in parentheses indicate corresponding elements or items shown in the drawings and in the detailed description below. Effect of the Invention

[0013] According to the sealing device for a walking beam type industrial furnace of the present invention, in an apparatus which has a dry seal structure and a liquid-sealed seal structure provided below it and which seals a movable post inserted into an insertion opening, the dry seal structure is composed of a member which blocks the insertion opening to insulate against heat inside the furnace body, and the liquid-sealed seal structure is composed of a sealing liquid and a sealing cylindrical plate which surrounds the entire circumference of the movable post and has its lower part immersed in the sealing liquid, so that it has excellent sealing properties, does not raise the dew point inside the furnace body, and does not generate flames.

[0014] That is, since the leakage of gas from inside the furnace body is prevented by both the dry seal structure and the liquid seal structure, high sealing performance can be achieved. In particular, the liquid seal structure seals with the seal liquid filled in the seal cylinder plate, so that leakage of gas from inside the furnace body can be reliably prevented and extremely high sealing performance can be achieved. In addition, since the high heat inside the furnace body is blocked by the dry seal structure, problems such as the action of high heat evaporating the seal liquid of the liquid seal structure provided below it, raising the dew point inside the furnace body, or generating flames can be prevented in advance.

[0015] Similarly, the sealing device for a walking beam type industrial furnace of the present invention has a dry seal structure and a liquid seal structure provided below it, so that these two seal structures can provide excellent sealing performance.

[0016] Here, the dry seal structure is composed of a slide seal plate that closes the insertion opening through which the movable post passes, and a packing that seals between the outer periphery of the movable post and the slide seal plate, so that the action of both can prevent leakage of gas inside the furnace body. Also, the liquid-sealed seal structure is composed of a seal cylinder plate suspended so as to surround the entire periphery of the movable post, and a trough filled with a seal liquid in which its lower end is immersed, so that the seal liquid can reliably prevent leakage of gas inside the furnace body that passes through the dry seal structure. Therefore, an extremely high sealing performance can be obtained.

[0017] In addition, since this sealing device has a liquid-sealed seal structure below the dry seal structure, evaporation of the seal liquid in the liquid-sealed seal structure and the occurrence of flames can be prevented in advance. This is because the sliding seal plate of the dry seal structure blocks the high heat inside the furnace body, preventing the high heat from directly acting on the seal liquid in the liquid-sealed seal structure.

[0018] Furthermore, according to the present invention, the sealing liquid is water, which reliably prevents gas inside the furnace body from leaking out, thereby providing excellent sealing performance.

[0019] The evaporation of this water is suppressed by the action of the dry seal structure, but the small amount of evaporated water is prevented from entering the furnace body by the presence of the sliding seal plate of the dry seal structure, so there is no problem of the dew point inside the furnace body rising.

[0020] Furthermore, according to the present invention, since the sealing liquid is non-flammable oil, the passage of gas inside the furnace body can be reliably prevented by this flame-retardant oil, and excellent sealing properties can be obtained. Although this flame-retardant oil has a property of being difficult to burn, the sliding seal plate of the dry seal structure blocks the high heat inside the furnace body, making it even more difficult to burn. Therefore, the occurrence of flames can be reliably prevented.

[0021] Furthermore, the sealing device for a walking beam type industrial furnace, which has a structure such as that of the present invention, which exhibits excellent sealing properties through a dry seal structure and a liquid seal structure, prevents an increase in the dew point inside the furnace body, and does not generate flames, is not described at all in the above-mentioned patent documents. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a front view of a walking beam type industrial furnace to which a sealing device according to an embodiment of the present invention is attached. [Diagram 2] FIG. 2 is a side view of the walking beam industrial furnace shown in FIG. [Diagram 3] 1 is an enlarged cross-sectional view showing a sealing device according to an embodiment of the present invention. [Figure 4] 4 is an enlarged plan view showing a dry seal structure of the seal device shown in FIG. 3. [Diagram 5] 4 is an enlarged plan view showing the liquid seal structure of the seal device shown in FIG. 3. [Figure 6] FIG. 13 is a configuration diagram showing a sealing device according to a conventional example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] A sealing device 1 for a walking beam type industrial furnace according to an embodiment of the present invention will be described with reference to FIGS. The sealing device 1 for a walking beam type industrial furnace according to this embodiment is a device for sealing a moving post 55 of a walking beam type industrial furnace 50. In this industrial furnace 50, a gas such as nitrogen gas is used to perform a decarburization prevention process by heat treatment on the material to be treated.

[0024] The upper end of the moving post 55 is fixed to a moving beam 53 that is installed horizontally inside the furnace body 51 of the industrial furnace 50 and transports the material W to be treated, and the lower end is fixed to a drive frame 54 that is installed horizontally outside the furnace body 51. The drive frame 54 is moved up and down by a lifting cylinder 56 and moved forward and backward by a forward and backward moving cylinder 57. Thus, the moving post 55, together with the drive frame 54 and the moving beam 53, repeats forward, downward, backward and upward movements in a lateral rectangular shape.

[0025] The movable post 55 is inserted into an insertion opening H formed vertically in the furnace wall structure 52. The furnace wall structure 52 is composed of a hearth 51a of the furnace body 51, a first furnace wall portion 52a integrally provided on the lower surface of the hearth 51a, and a second furnace wall portion 52b integrally provided on the lower surface of the first furnace wall portion 52a. The configuration of the furnace wall structure 52 is not limited to this three-layer structure.

[0026] The seal device 1 of this embodiment for sealing the moving post 55 includes a dry seal structure 10 and a liquid seal structure 20, as shown in FIGS. The dry seal structure 10 has a sliding seal plate 11, a packing 12, and a seal member 13. The sliding seal plate 11 is made of metal (steel, etc.), and is inserted into a sliding groove G formed horizontally in the second furnace wall portion 52b so as to be slidable in the front-rear direction. The sliding seal plate 11 has a hole 11a at approximately the center thereof, and the movable post 55 is inserted into this hole 11a with the outer peripheral surface of the movable post 55 being close to the hole 11a. The sliding seal plate 11 is large enough to always close the insertion opening H, including when it is slid forward and backward.

[0027] The packing 12 is fixedly attached to the sliding seal plate 11 in a state of elastic contact with the movable post 55 so as to seal the gap formed between the outer periphery of the movable post 55 and the hole 11a of the sliding seal plate 11. The specific location of the packing 12 is not particularly limited, and it can be provided, for example, on the upper surface of the sliding seal plate 11 or between the sliding seal plate 11 and the movable post 55.

[0028] The seal member 13 is provided on the second furnace wall portion 52b so as to surround the slide groove G. This seal member 13 is in elastic contact (sliding contact) with the lower surface of the slide seal plate 11, and functions in the same manner as the packing 12. Note that this seal member 13 can also be provided on the slide seal plate 11.

[0029] The liquid seal structure 20 includes a seal cylinder plate 21 and a trough (tank) 22, as shown in FIGS. The cylindrical seal plate 21 has a cylindrical shape and is hung down integrally from a portion surrounding the entire periphery (outer periphery) of the insertion opening H on the lower surface of the second furnace wall portion 52b in a state surrounding the entire periphery (outer periphery) of the moving post 55.

[0030] The trough 22 is box-shaped and is fixedly provided on the upper surface of the drive frame 54 and the lower end of the moving post 55 directly below the sealing cylinder plate 21. Therefore, the trough 22 moves forward, downward, backward and upward together with the moving post 55 (and the drive frame 54 and the moving beam 53). This trough 22 is filled with sealing liquid 23 in which almost the lower half of the sealing cylinder plate 21 is immersed. The sealing cylinder 21 has a length such that almost the lower half can be immersed in the sealing liquid 23 in the trough 22 even when the trough 22 is lowered. The sealing liquid 23 can be, but is not limited to, water or fire-retardant oil.

[0031] As can be understood from the above-mentioned configuration, in the dry seal structure 10 in the sealing device 1 according to this embodiment, the slide seal plate 11 is inserted into the slide groove G, so that the slide seal plate 11 and the packing 12 move forward and backward together with the moving post 55, but do not move upward or downward. In addition, the seal member 13 is provided on the second furnace wall portion 52b, so it does not move in either direction.

[0032] In the liquid-sealed seal structure 20 in the sealing device 1 according to this embodiment, only the sealing cylinder plate 21 is fixed to the furnace wall structure 52 (second furnace wall portion 52b), so the sealing cylinder plate 21 does not move in any direction. In addition, the trough 22 filled with the sealing liquid 23 is fixed to the drive frame 54 and the moving post 55, so it moves forward, downward, backward, and upward together with the drive frame 54 and the moving post 55 (and further the moving beam 53).

[0033] Next, the sealing action of the sealing device 1 according to this embodiment will be described. First, when the moving post 55 is in the raised and retracted state (see FIG. 3), the insertion opening H is closed by the slide seal plate 11 and packing 12 of the dry seal structure 10. Also, directly below, it is sealed by the seal cylinder plate 21 of the liquid seal structure 20 and the seal liquid 23 filled in the trough 22. Therefore, although there is a possibility that gas inside the furnace body 51 may pass through the dry seal structure 10 due to its structure, the gas that passes through is completely sealed off by the seal cylinder plate 21 and the seal liquid 23. Therefore, excellent sealing performance is ensured.

[0034] In addition, when water is used as the sealing liquid 23 of the liquid-sealed seal structure 20, the dry seal structure 10 provided above it blocks the insertion opening H, thereby preventing the high heat inside the furnace body 51 from directly acting on the sealing liquid 23. This suppresses water evaporation. Furthermore, the small amount of water that evaporates is blocked by the dry seal structure 10 and prevented from entering the furnace body 51. Therefore, the dew point inside the furnace body 51 does not increase.

[0035] Furthermore, when flame-retardant oil is used as the sealing liquid 23 of the liquid-sealed seal structure 20, the dry seal structure 10 blocks the insertion opening H and blocks the conduction of heat inside the furnace body 51, so that the flame-retardant oil does not generate flames.

[0036] When the moving post 55 moves forward from the retracted state, the inner peripheral surface of the sliding seal plate 11 (and packing 12) of the dry seal structure 10 is pressed against the outer peripheral surface of the moving post 55, and moves forward together with the moving post 55. At this time, the seal member 13 does not move. Also, the liquid-sealed seal structure 20 moves forward together with the moving post 55 with its trough 22 keeping the sealing cylinder plate 21 immersed in the sealing liquid. Therefore, the functions of the dry seal structure 10 and the liquid-sealed seal structure 20 are maintained as they are. In other words, excellent sealing properties are maintained, and evaporation of water and generation of flames in fire-retardant oil are also prevented.

[0037] When the moving post 55 moves down from the raised state, it moves while in sliding contact with the packing 12, so that the dry seal structure 10 maintains the same posture with all of its components (sliding seal plate 11, packing 12, and seal member 13). Also, in the liquid seal structure 20, the trough 22 moves down together with the moving post 55. In this state, the lower part of the sealing cylinder plate 21 maintains a state of being immersed in the sealing liquid 23. Therefore, the dry seal structure 10 and the liquid seal structure 20 exhibit the same functions as described above.

[0038] Next, when the moving post 55 moves backward from the forward position, the inner peripheral surface of the sliding seal plate 11 (and the packing 12) of the dry seal structure 10 is pressed against the outer peripheral surface of the moving post 55, and the sliding seal plate 11 and the packing 12 move backward together with the moving post 55 (the seal member 13 does not move). Also, the liquid seal structure 20 moves backward together with the moving post 55 with the trough 22 keeping the sealing cylinder plate 21 immersed in the sealing liquid. Therefore, the functions of the dry seal structure 10 and the liquid seal structure 20 are maintained as they are.

[0039] Then, when the moving post 55 moves upward from the downward state, the dry seal structure 10 maintains the same posture with all of its components (slide seal plate 11, packing 12, and seal member 13) just as they did in the downward movement. Also, in the liquid-sealed seal structure 20, the trough 22 moves upward together with the moving post 55. In this state, the lower part of the sealing cylinder plate 21 naturally maintains a state in which it is immersed in the sealing liquid 23. Therefore, the dry seal structure 10 and the liquid-sealed seal structure 20 continue to exhibit excellent sealing properties as before, and prevent the evaporation of water and the generation of flames in fire-retardant oil.

[0040] In this way, in the seal structure 1 according to this embodiment, the dry seal structure 10 closes the insertion opening H and the liquid seal structure 20 seals the insertion opening H in any state in which the moving post 55 moves forward, downward, backward, or upward. Therefore, it is possible to exhibit excellent sealing properties. In addition, the dew point inside the furnace body 51 is prevented from rising, and flames are not generated. [Explanation of symbols]

[0041] 1 Sealing device 10 Dry seal structure 11 Slide seal plate 11a Hole 12 Packing 13 Sealing material 20 Liquid seal structure 21 Seal cylinder plate 22 Trough 23 Seal Liquid 50 Walking beam industrial furnace 51 Furnace body 51a hearth 52 Furnace wall structure 52a First furnace wall 52b Second furnace wall 53 Moving Beam 54 Drive frame 55 Mobile Post 56 Lifting cylinder 57 Reciprocating cylinder B Seal Box G Slide groove H Insertion opening L water P Post S opening T-Trough Tank W Processing material

Claims

1. A sealing device for sealing a moving post in a walking beam type industrial furnace, the moving post having an upper end fixed to a moving beam that transports materials to be treated inside a furnace body and a lower end fixed to a drive frame that is driven by a lifting cylinder and a forward / backward cylinder outside the furnace body, the moving post being inserted into an insertion opening formed in a furnace wall structure including at least the hearth of the furnace body, It has a dry seal structure and a liquid seal structure. The dry seal structure, The member is configured to block the insertion opening and to insulate heat inside the furnace body, The liquid seal structure, A sealing device for a walking beam type industrial furnace, characterized in that it is composed of a sealing liquid provided below the dry seal structure and in which at least the lower end of the movable post is immersed, and a sealing cylindrical plate surrounding the entire circumference of the movable post on the lower side of the furnace wall structure and whose lower part is immersed in the sealing liquid, thereby preventing leakage of gas from inside the furnace body.

2. A sealing device for sealing a moving post in a walking beam type industrial furnace, the moving post having an upper end fixed to a moving beam that transports materials to be treated inside a furnace body and a lower end fixed to a drive frame that is driven by a lifting cylinder and a forward / backward cylinder outside the furnace body, the moving post being inserted into an insertion opening formed in a furnace wall structure including at least a hearth of the furnace body, It has a dry seal structure and a liquid seal structure. The dry seal structure, a slide seal plate having a hole through which the movable post passes at a substantially central portion, the slide seal plate being provided on the furnace wall structure so as to move in the left-right direction together with the movable post, and having a size large enough to close the insertion opening; a packing arranged to seal between the outer periphery of the moving post and the hole of the slide seal plate, The liquid seal structure, a cylindrical seal cylinder plate suspended from a portion surrounding the entire circumference of the insertion opening on the lower surface of the furnace wall structure so as to surround the entire circumference of the moving post; a sealing cylinder plate provided on the drive frame below the sealing cylinder plate, and a substantially box-shaped trough filled with sealing liquid in which at least the lower end of the sealing cylinder plate is immersed.

3. 3. A sealing device for a walking beam type industrial furnace according to claim 1 or 2, wherein the sealing liquid is water.

4. 3. A sealing device for a walking beam type industrial furnace according to claim 1 or 2, wherein the sealing liquid is a non-flammable oil.

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