JP2008224058A - Atmosphere control type induction heating furnace - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact atmosphere control-type induction heating furnace of high sealability, in which ceramic fiber heat insulating material is firmly lined without using a metallic material. <P>SOLUTION: This atmosphere control-type induction heating furnace 10 for performing heat treatment of a metallic band plate 11 passing through the inside of an induction heating means 13a, has a furnace shall 14 disposed inside of the induction heating means 13a to allow an atmosphere control gas to flow therein, an inorganic fiber block 15 disposed on an inner face of the furnace shell 14, and a plurality of mounting members of heat-proof inorganic material fixed to an inner face side of the furnace shell 14 at one side end portion, and penetrated through the inorganic fiber block 15 and exposed to a front side of the inorganic fiber block 15 at the other side, and the inorganic fiber block 15 is fixed to the inner face of the furnace shell 14 by connecting and fastening the parts exposed to the front side of the inorganic fiber block 15, of the mounting members. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

The present invention relates to an atmosphere control type induction heating furnace.

Conventionally, in heat treatment furnaces that heat treat steel under controlled atmosphere, steel was heated using a radiant tube, burner, or indirect heating method, but induction heating is used to improve the efficiency of heating and cooling. It is like that. At this time, for example, as shown in Patent Document 1, an outside air blocking wall is provided outside the heat treatment furnace to prevent intrusion of outside air. For example, as shown in Patent Documents 1 to 4, a heat insulating material is provided between the induction coil and the steel material. The heat radiation from the steel material that is placed and heated is suppressed.

JP-A-6-88194 JP-A-4-59931 JP-A-5-25544 Japanese Patent Laid-Open No. 11-257873

However, if an outside air blocking wall is provided on the outside as described in Patent Document 1, the apparatus becomes larger, and it becomes necessary to provide an open / close mechanism for the outside air blocking wall, which complicates the apparatus configuration and increases the manufacturing cost. The problem arises. In addition, as described in Patent Documents 2 and 3, when a metal member constituting the heat treatment furnace is present in the vicinity of the induction coil, the metal member is also heated at the same time when the steel material is heated. Therefore, cooling for cooling the metal member is performed. It is necessary to provide a mechanism, which causes a problem that the apparatus configuration becomes complicated and the manufacturing cost increases. Furthermore, to increase the efficiency of heating and lowering the temperature of the heat treatment furnace, it is preferable to use a ceramic fiber type heat insulating material that is lightweight and has a small heat capacity per unit volume, but the ceramic fiber type heat insulating material is firmly used without using hardware. Lining has become difficult. Thus, it has been proposed to use an adhesive as shown in Patent Document 4, but when the heat insulating material is fixed with the adhesive, since the change over time in the adhesive strength is large, the heat insulating material peels off during use. There's a problem.

The present invention has been made in view of such circumstances, and is to provide an atmosphere-controlled induction heating furnace that is compact and excellent in hermeticity, and in which a ceramic fiber-based heat insulating material is firmly lined without using hardware. Objective.

An atmosphere control type induction heating furnace according to the present invention that meets the above-mentioned object is an atmosphere control type induction heating furnace that heat-treats a metal strip passing through the inside of induction heating means.
A furnace shell provided inside the induction heating means and through which an atmosphere control gas flows;
An inorganic fiber block disposed on the inner surface of the furnace shell;
A plurality of heat-resistant inorganic material-based attachment members having one end fixed to the inner surface side of the furnace shell and the other side penetrating the inorganic fiber block and exposed to the front side of the inorganic fiber block; And
The said inorganic fiber block is fixed to the inner surface of the said furnace shell by connecting and fastening the parts exposed to the front side of this inorganic fiber block of the said attachment member.

In the atmosphere control type induction heating furnace according to the present invention, the inorganic fiber block can be configured using a ceramic fiber blanket.

In the atmosphere control type induction heating furnace according to the present invention, the mounting member includes a stopper fixed to the furnace shell, and a string member connected to the stopper and protruding through the inorganic fiber block; can do.
Moreover, it is preferable that the area | region which exists in the said inorganic fiber block by the said stopper and the said string member is hardened with water glass.
Moreover, it is preferable that the inner surface side of the said furnace shell is provided with the latching hole which can be latched by inserting the said stopper side by side with predetermined spacing.
And when fixing the attachment member to the furnace shell, it is possible to attach a rod that comes into contact with the side surface of the string member, one end abuts against the stopper, and the other end projects from the other end of the string member. preferable.

In the atmosphere control type induction heating furnace according to the present invention, the atmosphere control gas is preferably one of a reducing gas and a non-oxidizing gas.
Here, the atmosphere control gas may be a mixed gas of nitrogen gas, hydrogen gas, and ammonia gas.

In the atmosphere controlled induction heating furnace according to the present invention, it is preferable that the furnace shell has airtightness.
Here, the furnace shell may be formed of fiber reinforced plastic.
The heat resistance temperature of the furnace shell is preferably 350 ° C. or more and 450 ° C. or less, the heat treatment temperature of the metal strip is 620 ° C. or more and 750 ° C. or less, and the thickness of the inorganic fibrous block is preferably 50 mm or less.

In the atmosphere control type induction heating furnace according to claims 1 to 11, the inorganic fiber block disposed on the inner surface of the furnace shell has one end fixed to the furnace shell and the other side penetrating the inorganic fiber block. Since the exposed parts of the mounting members exposed on the front side of the inorganic fiber block are fastened by joining together and tightening, the tightening force does not decrease even at high temperatures, and the inorganic fiber block will fall off during use. Therefore, the atmosphere control type induction heating furnace can be used stably.
And since an inorganic fibrous block is used, an atmosphere control type induction heating furnace can be reduced in weight and efficiency of raising and lowering temperature can be improved. In addition, since the inorganic fibrous block has high heat insulating properties, the thickness can be reduced, and the atmosphere-controlled induction heating furnace can be configured compactly.

In the atmosphere control type induction heating furnace according to claim 2, since a ceramic fiber blanket that is lightweight and has excellent heat insulating properties is used as the inorganic fiber block, the atmosphere control type induction heating furnace can be reduced in weight, and the inorganic fiber block Therefore, the atmosphere control type induction heating furnace can be made more compact.

In the atmosphere control type induction heating furnace according to the third aspect, since the stopper is provided at one end of the attachment member, the attachment member can be prevented from being pulled out from the inorganic fiber block.
In the atmosphere control type induction heating furnace according to claim 4, since the region existing in the inorganic fibrous block of the stopper and the string member is hardened with water glass, the self-supporting property of the attachment member is improved, and the attachment member Handling becomes easy.

In the atmosphere control type induction heating furnace according to the fifth aspect, the fixing of the attachment member to the inner surface side of the furnace shell is facilitated, and the attachment of the inorganic fiber block can be performed efficiently.
In the atmosphere control type induction heating furnace according to the sixth aspect, since the rod is attached along the standing string member, the string member can be easily passed through the inorganic fibrous block.

In the atmosphere controlled induction heating furnace according to the ninth aspect, since the furnace shell has airtightness, the furnace shell can be reduced in weight and size.
In the atmosphere control type induction heating furnace according to the tenth aspect, since the furnace shell is made of fiber reinforced plastic, it is possible to easily obtain a lightweight and high-strength shell having airtightness.
In the atmosphere control type induction heating furnace according to claim 11, since the thickness of the inorganic fibrous block is 50 mm or less, even if the furnace shell is made compact, the volume of the effective region through which the metal strip passes in the furnace shell is reduced. Can be bigger.

Next, embodiments of the present invention will be described with reference to the accompanying drawings for understanding of the present invention.
Here, FIG. 1 is a perspective view of an atmosphere control type induction heating furnace according to an embodiment of the present invention, and FIG. 2 is a state of an inorganic fiber block arranged on one inner surface of a furnace shell of the atmosphere control type induction heating furnace. FIG. 3 is a perspective view of a mounting member of the same atmosphere control type induction heating furnace, and FIGS. 4A and 4B are fixing the mounting member to the inner surface side of the furnace shell of the same atmosphere control type induction heating furnace. (C) is a cross-sectional view taken along the line PP of (B), (D) is a cross-sectional view taken along the line Q-Q of (B), and FIG. FIGS. 6A to 6D are explanatory views showing a state in which a mounting member is fixed to one inner surface of a furnace shell of the same atmosphere control type induction heating furnace, and FIGS. 6A to 6D are inorganic on one inner surface of the furnace shell of the same atmosphere control type induction heating furnace. It is explanatory drawing which shows the process at the time of arrange | positioning a fibrous block.

As shown in FIGS. 1 and 2, the atmosphere control type induction heating furnace 10 according to one embodiment of the present invention is provided at both ends thereof on the upstream side and the downstream side of the atmosphere control type induction heating furnace 10, respectively. Thin steel plates 11, which are examples of metal strips that are connected to an atmosphere control type heat treatment furnace (not shown) through flanges (not shown) and pass through the inside from the upstream side to the downstream side, are provided at the front and rear. Heat treatment is performed together with the atmosphere controlled heat treatment furnace. And the atmosphere control type induction heating furnace 10 includes an induction heating means 13a including a frame-shaped iron core 12 disposed so as to surround the passing thin steel plate 11 from the outside and an induction coil 13 provided in the iron core 12, Arranged on the inner surface of the furnace shell 14, which is provided inside the iron core 12 and in which a reducing gas, which is an example of an atmosphere control gas, for example, a mixed gas of nitrogen gas, hydrogen gas, and ammonia gas flows ) Of the inorganic fiber block 15 and a plurality of heat resistances, one end of which is fixed to the inner surface side of the furnace shell 14 and the other side portion penetrates the inorganic fiber block 15 and is exposed to the front side of the inorganic fiber block 15. And an attachment member 16 made of a conductive inorganic material. The inorganic fiber block 15 is fixed to the inner surface of the furnace shell 14 by connecting and tightening portions of the attachment member 16 exposed on the front side of the inorganic fiber block 15. This will be described in detail below.

The furnace shell 14 has a cylindrical body 17 whose cross section is, for example, rectangular, and flanges for connecting to the front and rear atmosphere controlled heat treatment furnaces are attached to both ends of the cylindrical body 17. Here, the cylindrical body 17 is formed by adhering plate members 18 and 19 made of carbon fiber reinforced epoxy resin, which is an example of fiber reinforced plastic, with a combination adhesive. Since the plate members 18 and 19 themselves have gas non-permeability (air tightness), the cylindrical body 17 formed by assembling the pair of plate members 18 and the pair of plate members 19 constituting the opposite side walls with an adhesive also has air tightness. In addition, the airtightness of the furnace shell 14 can be maintained. For this reason, even if a mixed gas of nitrogen gas, hydrogen gas, and ammonia gas flows through the furnace shell 14 (tubular body 17), the mixed gas can be prevented from leaking to the outside.

The inorganic fibrous block 15 is configured by laminating alumina fiber blankets 20, 20a to 20e, which are examples of ceramic fiber blankets. By using a blanket material that is lightweight and has excellent heat insulating properties, the inorganic fiber block 15 can be reduced in weight, and the required thickness of the inorganic fiber block 15 can be reduced, and the atmosphere control type induction heating furnace 10 can be reduced in weight and compact. Can be achieved.
Here, the required thickness of the inorganic fibrous block 15 is that the temperature of the inner surfaces of the plate members 18 and 19 constituting the furnace shell 14 can be kept below the heat resistance temperature of the plate members 18 and 19. Refers to thickness. For example, since the heat resistance temperature of the carbon fiber reinforced epoxy resin plate materials 18 and 19 is 350 ° C. or higher and 450 ° C. or lower, when the heat treatment temperature of the thin steel plate 11 is 620 ° C. or higher and 750 ° C. or lower, the thickness of the inorganic fibrous block 15 Can be 50 mm or less.

As shown in FIG. 3, the attachment member 16 is connected to the flange portion 21 which is an example of a stopper fixed to the inner surface side of the plate members 18 and 19 constituting the furnace shell 14 and the inorganic fiber block 15. And a string member 22 that is exposed to the front side of the inorganic fiber block 15. Here, the collar part 21 is formed by cutting an alumina cloth (thickness 5 to 6 mm), which is an example of a ceramic cloth, into a disk shape (diameter 8 to 15 mm). The string member 22 is formed by cutting an alumina rope (diameter 3 to 8 mm), which is an example of a ceramic rope, into a predetermined length. The predetermined length is exposed to the front side of the inorganic fiber block 15 in consideration of a fastening allowance when the string member 22 is connected to the collar portion 21, the thickness of the inorganic fiber block 15, and workability of the knotting work. Total length. And the fixation of the collar part 21 and the string member 22 forms the hole 23 in the center part of the collar part 21, for example, inserts one side of the string member 22 in this hole 23, and it is for latching at the edge part of one side. This is done by forming a knot 24.

In addition, the flange 21 of the mounting member 16 and the region existing in the inorganic fiber block 15 when the string member 22 is passed through the inorganic fiber block 15 are impregnated with water glass, dried and cured. ing. Further, when the attachment member 16 is fixed to the inner surface side of the plate members 18 and 19 constituting the furnace shell 14, it comes into contact with the side surface of the string member 22, one end abuts against the collar portion 21, and the other end is the string member. A wire 25 (diameter 3 to 4 mm), which is an example of a rod protruding from the other end of the wire 22 by a length of 40 to 60 mm, for example, is attached to the string member 22 using, for example, an adhesive tape 26.

As shown in FIGS. 4A to 4D and FIG. 5, the hook portion 21 can be fitted on the inner surface side of the plate members 18 and 19 constituting the furnace shell 14 so that the hook portion 21 can be hooked. Holes 27 are provided side by side at a predetermined interval. Here, the retaining hole 27 is formed perpendicularly to the inner surface side of the plate members 18 and 19 and communicates with the insertion portion 28 into which the flange portion 21 can be fitted and the upper side of the side surface of the insertion portion 28 and extends horizontally. A traverse groove 29 into which the member 22 can be inserted and a flange portion 21 that extends horizontally and communicates with the lower side of the side surface of the insertion portion 28 and that fits into the insertion portion 28 with the upper portion communicating with the bottom of the traverse groove 29 can traverse. And a traversing unit 30.

With the configuration as described above, the flange portion 21 of the attachment member 16 in a state where the wire 25 is attached to the string member 22 is inserted into the insertion portion 28 of the latch hole 27 formed in the plates 18 and 19. The collar 21 can be moved to the end of the traversing section 30 by moving the collar 21 with the traversing section 30 and the wire member 25 provided with the wire 25 in the traversing groove 29. It can be hooked on the upper surface on both sides of the traversing portion 30. At this time, when the string member 22 is penetrated through the inorganic fiber block 15, the region existing in the inorganic fiber block 15 by the string member 22 and the flange portion 21 are cured using water glass. The movement of the part 21 in the traversing part 30 can be easily performed. As a result, as shown in FIG. 5, the attachment member 16 in a state where the wire 25 is attached to the string member 22 on the inner surface side of the plate member 19 can be erected.

Further, when the alumina fiber blanket 20 is lowered from above the inner surfaces of the plate members 18 and 19 on which the mounting member 16 is erected, it is guided by the wire 25 and easily penetrates the string member 22 of the mounting member 16 into the alumina fiber blanket 20. Can be made. For this reason, the inorganic fiber block 15 can be disposed on the inner surfaces of the plates 18 and 19 by sequentially passing the predetermined number of alumina fiber blankets 20a to 20e through the string member 22. Then, when a predetermined number of alumina fiber blankets 20 and 20a to 20e pass through the string member 22, the adhesive tape 26 is removed and the wire 25 is removed from the string member 22 so that the inorganic fiber block 15 of the string member 22 is on the front side. The inorganic fiber block 15 can be fixed to the inner surfaces of the plate members 18 and 19 (the inner surface of the furnace shell 14) by connecting and tightening the adjacent parts in the exposed portion.

Next, a method of arranging the inorganic fiber block 15 on the inner surface of the furnace shell 14 in the atmosphere control type induction heating furnace 10 according to the embodiment of the present invention will be described.
First, as shown in FIG. 5, the attachment member 16 in a state where the wire 25 is attached to the string member 22 is erected with respect to the retaining hole 27 formed on the inner surface side of the plate material 19. When the attachment members 16 are attached to all the retaining holes 27, as shown in FIG. 6A, the alumina fiber blanket 20 from above the inner surface of the plate member 19 on which the attachment members 16 are erected. And the alumina fiber blanket 20 is passed through the string member 22 provided with the wire 25, so that the inner surface of the plate material 19 is covered with the alumina fiber blanket 20. Thereby, arrangement | positioning of the alumina fiber blanket 20 of the 1st layer is complete | finished. 6A, 6 </ b> B, and 6 </ b> C, a part of the mounting member 16 erected on the plate member 19 is omitted.

Next, as shown in FIG. 6B, the position of the alumina fiber blanket 20a constituting a part of the second layer is adjusted so as to cover one side of the alumina fiber blanket 20 constituting the first layer. Then, the string member 22 is pierced. At this time, the longitudinal direction of the alumina fiber blanket 20a constituting a part of the second layer is set to be orthogonal to the joint direction of the alumina fiber blankets 20 of the first layer, for example. Then, as shown in FIG. 6C, an alumina fiber blanket 20b whose position is adjusted so that one side covers the alumina fiber blanket 20a and the other side covers a part of the alumina fiber blanket 20 constituting the first layer. The string member 22 standing up is penetrated. Thus, a part of the third layer is formed on one side of the plate material 19 and a part of the second layer is formed together with the alumina fiber blanket 20a.

Subsequently, as shown in FIG. 6D, one side covers the alumina fiber blanket 20b constituting a part of the second layer, and the other side covers a part of the alumina fiber blanket 20 constituting the first layer. The alumina fiber blanket 20c, whose position is adjusted in this way, is passed through the standing string member 22. Further, an alumina fiber blanket 20d whose position is adjusted so that one side covers the alumina fiber blanket 20c constituting a part of the second layer and the other side covers a part of the alumina fiber blanket 20 constituting the first layer is provided. The string member 22 standing up is penetrated. Then, the alumina fiber blanket 20d is pierced through the standing string member 22 with the alumina fiber blanket 20e adjusted in position so as to cover a region constituting a part of the second layer with the alumina fiber blanket 20d. Thereby, the inorganic fiber block 15 which consists of three layers comprised by the alumina fiber blanket 20, 20a-20e is arrange | positioned at the inner surface side of the board | plate material 19. As shown in FIG.

When the arrangement of the inorganic fiber block 15 on the inner surface side of the plate material 19 is completed, the adhesive tape 26 is removed from each string member 22 protruding from the surface of the inorganic fiber block 15, and the wire 25 and the string member 22 are separated. The wire 25 is removed. Next, the adjacent parts of the string member 22 exposed on the front side of the inorganic fiber block 15 are combined and tightened. Thereby, the inorganic fiber block 15 is pressed and fixed to the inner surface side of the plate material 19.
The inorganic fiber block 15 is similarly fixed to the inner surface side of the plate member 18. And the furnace shell 14 is formed by combining the board | plate materials 18 and 19 with which the inorganic fiber block 15 was fixed to the inner surface side, and joining with an adhesive agent.

As described above, the present invention has been described with reference to the embodiment. However, the present invention is not limited to the configuration described in the above-described embodiment, and the matters described in the scope of claims. Other embodiments and modifications conceivable within the scope are also included.
For example, the stopper of the mounting member is formed by cutting an alumina cloth into a disk shape and joining it to an alumina rope that constitutes a string member. However, a transverse groove of a retaining hole formed in the furnace shell on one side of the alumina rope A stopper can also be formed by providing a knot of a size that cannot pass through.
Further, the atmosphere control gas can be a non-oxidizing gas such as nitrogen gas, argon gas, or a mixed gas of nitrogen gas and argon gas.

It is a perspective view of the atmosphere control type induction heating furnace which concerns on one embodiment of this invention. It is a perspective view which shows the state of the inorganic fiber block arrange | positioned on one inner surface of the furnace shell of the same atmosphere control type induction heating furnace. It is a perspective view of the attachment member of the same atmosphere control type induction heating furnace. (A), (B) is a perspective view, a plan view of a retaining hole used when fixing a mounting member to the inner surface side of the furnace shell of the same atmosphere control type induction heating furnace, (C) is P of (B) -P arrow sectional drawing, (D) is QQ arrow sectional drawing of (B). It is explanatory drawing which shows the state which fixed the attachment member to one inner surface of the furnace shell of the same atmosphere control type induction heating furnace. (A)-(D) are explanatory drawings which show the process at the time of arrange | positioning an inorganic fibrous block to one inner surface of the furnace shell of the same atmosphere control type induction heating furnace.

Explanation of symbols

10: Atmosphere control type induction heating furnace, 11: Thin steel plate, 12: Iron core, 13: Induction coil, 13a: Induction heating means, 14: Furnace shell, 15: Inorganic fiber block, 16: Mounting member, 17: Cylindrical body 18, 19: plate material, 20, 20a to 20e: alumina fiber blanket, 21: collar, 22: string member, 23: hole, 24: knot, 25: wire, 26: adhesive tape, 27: retaining hole, 28: insertion part, 29: transverse groove, 30: transverse part

Claims (11)

In an atmosphere control type induction heating furnace that heat-treats a metal strip passing inside the induction heating means,
A furnace shell provided inside the induction heating means and through which an atmosphere control gas flows;
An inorganic fiber block disposed on the inner surface of the furnace shell;
A plurality of heat-resistant inorganic material-based attachment members having one end fixed to the inner surface side of the furnace shell and the other side penetrating the inorganic fiber block and exposed to the front side of the inorganic fiber block; And
The atmosphere control type induction heating furnace, wherein the inorganic fiber block is fixed to the inner surface of the furnace shell by joining and tightening portions exposed on the front side of the inorganic fiber block of the mounting member . The atmosphere control type induction heating furnace according to claim 1, wherein the inorganic fiber block is configured by using a ceramic fiber blanket. The atmosphere control type induction heating furnace according to any one of claims 1 and 2, wherein the mounting member includes a stopper fixed to the furnace shell, and is connected to the stopper and passes through the inorganic fiber block. An atmosphere control type induction heating furnace having a protruding string member. The atmosphere control type induction heating furnace according to claim 3, wherein a region of the stopper and the string member existing in the inorganic fiber block is hardened with water glass. 5. The atmosphere control type induction heating furnace according to claim 3, wherein the inner surface of the furnace shell is provided with retaining holes arranged at predetermined intervals so that the stopper can be fitted therein. An atmosphere control type induction heating furnace characterized by that. The atmosphere control type induction heating furnace according to any one of claims 3 to 5, wherein when the attachment member is fixed to the furnace shell, one end of the string member comes into contact with a side surface of the string member. An atmosphere control type induction heating furnace characterized in that a rod is attached so that the other end protrudes from the other end of the string member. The atmosphere control type induction furnace according to any one of claims 1 to 6, wherein the atmosphere control gas is any one of a reducing gas and a non-oxidizing gas. heating furnace. The atmosphere control type induction heating furnace according to claim 7, wherein the atmosphere control gas is a mixed gas of nitrogen gas, hydrogen gas, and ammonia gas. The atmosphere control type induction heating furnace according to any one of claims 1 to 8, wherein the furnace shell has airtightness. The atmosphere control type induction heating furnace according to claim 9, wherein the furnace shell is made of fiber reinforced plastic. The atmosphere control type induction heating furnace according to claim 10, wherein the heat resistance temperature of the furnace shell is 350 ° C or higher and 450 ° C or lower, the heat treatment temperature of the metal strip is 620 ° C or higher and 750 ° C or lower, and the inorganic fibrous block The atmosphere control type induction heating furnace characterized by having a thickness of 50 mm or less.

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