JP7024210B2 - In-core lining of continuous annealing furnace and continuous annealing furnace - Google Patents

Description

The present invention relates to an in-core lining of a continuous annealing furnace, and more particularly to an in-core lining provided with a roll insertion hole through which the end side of a roll is inserted. More specifically, the present invention relates to an in-core lining of a continuous annealing furnace in which the in-core lining has a lining layer of ceramic fibers. The present invention also relates to a continuous annealing furnace having this in-core lining.

Conventionally, ceramic fibers having excellent properties as a lightweight refractory material and a heat insulating material have been used for the in-furnace lining of continuous annealing treatment equipment (for example, Patent Documents 1 and 2).

Ceramic fibers are produced by fiberizing a ceramic material in a high-temperature molten state by a spinning method using centrifugal force or a blowing method in which the ceramic material is blown off with high-speed compressed air. The ceramic fiber contains non-fibrous particles, that is, shots, which remain in the form of particles that cannot be completely turned into fibers, and these shots cause dust.

In order to prevent such dust generated from the in-furnace lining material, Patent Documents 1 and 2 describe that the ceramic fiber block is coated with an alumina heat-resistant cloth made of an inorganic fiber or a crystalline alumina fiber blanket. ing. Patent Document 2 describes that the crystalline alumina fiber blanket having a shot content of 45 μm or more and a shot content of 3% or less is used.

Japanese Unexamined Patent Publication No. 2002-364985 Japanese Unexamined Patent Publication No. 2006-10107

The in-core lining of the continuous annealing furnace is provided with a roll insertion hole through which the end side of the roll (hearth roll) is inserted (paragraph 0018 and FIG. 2 of Patent Document 2). Ceramic fibers constituting the lining layer are exposed on the inner peripheral surface of the roll insertion hole (FIG. 2 of Patent Document 2). Therefore, dust such as shots may be generated from the inner peripheral surface of the roll insertion hole.

An object of the present invention is to provide an in-core lining of a continuous annealing furnace and a continuous annealing furnace in which dust generation from the inner peripheral surface of a roll insertion hole is prevented.

The in-fireware lining of the present invention includes a lining layer having a ceramic fiber blanket and an in-core surface-covered blanket made of an alumina fiber blanket having a shot content of 45 μm or more and 3% or less, which covers the inner surface of the lining layer. In the in-furnace lining of a continuous quenching furnace provided with a roll insertion hole penetrating in and out of the furnace, it is made of an alumina fiber blanket having a shot content of 45 μm or more and a shot content of 3% or less, which covers the inner peripheral surface of the roll insertion hole. It is characterized by having a blanket covered with an insertion hole.

The continuous annealing furnace of the present invention has such an in-core lining.

In one aspect of the present invention, at least a part of the roll insertion hole has a tapered shape having a small diameter toward the outside of the furnace, and the insertion hole covering blanket has a tapered portion overlapping the inner peripheral surface of the tapered shape. have.

In one aspect of the present invention, the insertion hole covered blanket has a flange portion that overlaps the inner surface of the furnace blanket around the roll insertion hole from the inside of the furnace.

In one aspect of the present invention, the insertion hole covering blanket is formed by sewing a plurality of substantially fan-shaped sheets.

In one aspect of the present invention, two or more insertion hole-coated blankets are provided in a laminated state, and in the laminated insertion hole-covered blanket, the sutured portions thereof are arranged in a non-face-to-face state.

In one aspect of the present invention, a rod erected from the iron shell of the furnace shell penetrates the ceramic fiber blanket, and a washer and a nut attached to the tip of the rod make the ceramic fiber blanket and the inner surface covering blanket of the furnace. And the insertion hole covering blanket is held in the furnace shell iron skin.

In one aspect of the present invention, the rod has a main rod erected vertically on the furnace shell iron skin and an oblique rod connected in the middle of the main rod, and the tip portion of the main rod is The furnace inner surface covering blanket and the flange portion are penetrated, and the tip portion of the inclined rod penetrates the insertion hole covering blanket on the inner peripheral surface of the roll insertion hole.

According to the present invention, by covering the inner peripheral surface of the roll insertion hole with an alumina fiber blanket having a shot content of 45 μm or more and 3% or less, dust generation from the inner peripheral surface of the roll insertion hole is prevented.

It is a perspective view explaining the in-core lining of the continuous annealing furnace which concerns on embodiment. FIG. 2 is a sectional view taken along line II-II of FIG. It is an enlarged sectional view of a part of the lining in a furnace. It is an exploded perspective view explaining the in-core lining of the continuous annealing furnace which concerns on embodiment. It is an exploded perspective view explaining the in-core lining of the continuous annealing furnace which concerns on embodiment. It is a top view which shows the sewing method of a covering blanket. It is a top view which shows the sewing method of a covering blanket.

Hereinafter, embodiments will be described with reference to the drawings.

The in-core lining 1 of the continuous quenching furnace according to this embodiment is a square furnace shell iron skin 2 and a ceramic in which a plurality of layers (4 layers in this embodiment) are laminated inside the furnace shell iron skin 2. A ceramic fiber lining layer 4 made of a fiber blanket 3 (3A to 3D), a furnace inner surface covering blanket 5 made of an alumina fiber blanket covering the inner surface of the ceramic fiber lining layer 4, and a roll through which the hearth roll 20 is inserted. It has a roll insertion hole inner peripheral surface covering blanket (hereinafter, referred to as an insertion hole covering blanket) 6 or the like, which is made of an alumina fiber blanket and covers the inner peripheral surface of the insertion hole 21. The furnace inner surface coated blanket 5 and the insertion hole coated blanket 6 are both made of an alumina fiber blanket having a shot content of 45 μm of 3% or less.

As shown in FIG. 2, in this embodiment, a tapered portion 20a having a smaller diameter toward the outside of the furnace and a small diameter portion 20b having an equal diameter outside the furnace than the tapered portion 20a are provided on the end side of the hearth roll 20. It is provided. The tapered portion 20a and the small diameter portion 20b are inserted into the roll insertion hole 21. As shown in FIG. 3, the inside of the furnace of the roll insertion hole 21 is a tapered hole portion 21a that follows the tapered portion 20a. Further, in the roll insertion hole 21, the portion through which the small diameter portion 20b of the hearth roll 20 is inserted is a cylindrical hole portion 21b having the same diameter.

The ceramic fiber blanket 3 has a square plate shape, and a through hole serving as a roll insertion hole 21 is provided in the central portion of the plate. The number of laminated ceramic fiber blankets 3 is preferably 4 to 10, particularly preferably about 5 to 8.
FIG. 2 describes an embodiment in which a plurality of layers are laminated inside the furnace. The ceramic fiber blanket 3 is laminated in a cross, radial or mosaic pattern, and the fiber tip of the ceramic fiber blanket 3 is positioned in the roll insertion hole 21. It may be an embodiment.

As is clearly shown in FIGS. It has a flap portion 5b of four leaves extending from. The main surface 5a is provided with a circular opening 5c having the same diameter as the through hole of the ceramic fiber blanket 3 (3D) inside the furnace.

In the furnace inner surface covering blanket 5, the main surface 5a is overlapped on the inner surface of the ceramic fiber blanket 3 (3D) on the innermost side of the furnace, and the flap portion 5b is bent so as to be overlapped on the side surface of the ceramic fiber blanket 3 so that the ceramic fiber lining layer 4 is overlapped. Being covered with. The side sides of the adjacent flap portions 5b are sewn together with an alumina fiber thread or the like in advance or after being overlapped with the side surface of the ceramic fiber blanket 3.

As shown in FIGS. It has a flange portion 6c that expands from the edge portion of the tapered portion 6a on the inside (large diameter side) of the furnace.

In this embodiment, one insertion hole covering blanket 6 is attached to the roll insertion hole 21.

In this embodiment, the insertion hole covering blanket 6 is manufactured by stitching a predetermined number of fan-shaped sheets 10 (8 sheets in FIG. 6) as shown in FIG. The sheet 10 includes a pair of radial sides 10a, 10a, an arc side 10b having a small radius of curvature connecting one end sides of the radial sides 10a, 10a, and the other ends of the radial sides 10a, 10a. It has an arc side 10c with a large radius of curvature.

The insertion hole covering blanket 6 shown in FIG. 5 is manufactured by aligning the end faces of the portions of adjacent sheets 10 along the radial side 10a and suturing the end faces with an alumina fiber thread (not shown).
Of the sheet 10, the portion along the arc side 10c is the flange portion 6c, the portion along the arc side 10b is the cylindrical portion 6b, and the portion between the two is the tapered portion 6a.

In order to more reliably prevent dust such as shots from flowing out from the stitched portions 6s of the sheets 10 and 10, the two insertion hole covering blankets 6 and 6 are placed so that the stitched portions 6s do not overlap with each other. It may be inserted into the roll insertion hole 21 (that is, so as to be in a non-face-to-face state). In this embodiment (not shown), the sutured portion 6s of the insertion hole covering blanket 6 arranged inside the furnace is placed near the middle of the sutured portions 6s and 6s of the blanket 6 arranged on the ceramic fiber lining layer 4 side. Position it.

In this embodiment, each ceramic fiber blanket 3, the furnace inner surface coated blanket 5, and the insertion hole coated blanket 6 are fixed to the furnace shell iron skin 2 by rods 7 and 7A erected from the furnace shell iron skin 2. ing.

The rod 7 has a main rod 7a perpendicular to the furnace shell iron skin 2 and an oblique rod 7b branched from an intermediate portion in the longitudinal direction of the main rod 7a. Male screws are engraved on the outer peripheral surfaces of the tips of the main rod 7a and the slanted rod 7b, respectively, and the nut 8 can be screwed on.

Of the ceramic fiber blankets 3, do the three ceramic fiber blankets 3 (3A to 3C) arranged on the furnace shell iron skin 2 pass through the slanted rod 7b when each is stacked on the furnace shell iron skin 2? Alternatively, a fiber split (not shown) to be inserted is provided.

In order to form the ceramic fiber lining layer 4 by laminating the ceramic fiber blankets 3A to 3D on the furnace shell iron skin 2, the ceramic fiber blankets 3A to 3D are pierced through the main rod 7a, and the inclined rod 7b is made of the ceramic fiber. It is fitted into the slits of blankets 3A to 3C. In the state of FIG. 3, the inclined rod 7b is arranged so as to penetrate the second and third ceramic fiber blankets 3 from the furnace shell iron skin 2 side. The tip of the inclined rod 7b is exposed to the tapered hole portion 21a.

Next, the ceramic fiber lining layer 4 is covered with the furnace inner surface covering blanket 5. Further, the tapered portion 6a and the cylindrical portion 6b of the insertion hole covering block 6 are overlapped with the inner peripheral surface of the roll insertion hole 21, and the flange portion 6c is overlapped with the furnace inner surface covering blanket 5. The tip of the main rod 7a is pierced through the blanket 5 and the flange portion 6c, and the tip of the oblique rod 7b is pierced through the tapered portion 6a of the insertion hole covering blanket 6. Next, the washer 9 is fitted into the tip portions of the main rod 7a and the slanted rod 7b, and the nut 8 is screwed. As a result, the portions of the ceramic fiber blankets 3 and the blankets 5 and 6 in the vicinity of the roll insertion holes 21 are fixed to the furnace shell iron skin 2.

As shown in FIG. 3, the length of the main rod 7a is assumed to be substantially equal to the thickness of the laminated ceramic fiber blankets 3 (3A to 3D) and the total thickness of the furnace inner surface covering blanket 5 and the flange portion 6c. There is. That is, the tip surface of the main rod 7a is substantially flush with the inner surface of the furnace of the flange portion 6c. Further, the length of the oblique rod 7b is such that the tip surface thereof is substantially flush with the inner peripheral surface of the tapered portion 6a.

Each washer 9 is inserted into the tip portions of the main rod 7a and the inclined rod 7b so as to be pushed into the flange portion 6c and the tapered portion 6a, and the nut 8 is screwed into the washer 9. Therefore, the tips of the main rod 7a and the inclined rod 7b hardly or hardly protrude from the inner peripheral surfaces of the flange portion 6c and the tapered portion 6a.

As shown in FIGS. 4 and 5, the rod 7A is erected in the vicinity of the four corners of the furnace shell iron skin 2. This rod 7A has the same straight rod shape as the main rod 7a. The portions near the four corners of each ceramic fiber blanket 3 and the inner surface covering blanket 5 of the furnace are pierced through the rod 7A, a washer 9 is inserted into the tip of the rod 7A, and a nut 8 is screwed. As a result, the portions near the corners of the ceramic fiber blanket 3 and the furnace inner surface covering blanket 5 are fixed to the furnace shell iron skin 2. The tip surface of the rod 7A is also substantially flush with the inner surface of the furnace inner surface covering blanket 5 around the rod 7A, and does not substantially protrude into the furnace.

In the furnace lining 1 of the continuous annealing furnace configured in this way, the inner surface of the ceramic fiber blanket 3 is covered with the inner surface covering blanket 5, and the inner peripheral surface of the roll insertion hole 21 is covered with the insertion hole. Since it is covered with the blanket 6, dust is prevented from being generated. In particular, in this embodiment, since the flange portion 6c of the insertion hole covering blanket 6 overlaps the peripheral portion of the circular opening 5c of the furnace inner surface covering blanket 5, the boundary portion between the circular opening 5c and the insertion hole covering blanket 6 The generation of dust from the air is also prevented.

In the above embodiment, as shown in FIG. 6, the sheets 10 are sewn together to form the insertion hole covering blanket 6, but as shown in FIG. 7, the size of a plurality of sheets (for example, two sheets) is set. The sheet 10A provided may be used. In this sheet 10A, a cut 10d is cut in the radial direction from the middle of the inner arc side 10b. By suturing the radial sides 10a of the sheet 10A and suturing the opposite sides of the cut 10d so as to close the cut 10d, an insertion hole covering blanket having the same shape as the insertion hole covering blanket 6 is formed.

Next, an alumina fiber blanket having a shot content of 45 μm or less and a shot content of 3% or less, which is suitable for use in the present invention, will be described.

Since it is preferable that there is no particulate foreign matter of 45 μm or more that affects the scratches on the steel sheet in the continuous annealing furnace, the alumina fiber blanket preferably has a shot content of 45 μm or more of 3% or less, particularly 2% or less. The measurement of the shot content of 45 μm or more contained in the alumina fiber blanket is based on the measurement of the shot content contained in the ceramic fiber blanket of JIS R3311 (the nominal size of sieve JIS Z8801 is 212 μm) of 45 μm of 325 mesh. Measure using a sieve.

The alumina fiber blanket used in the present invention preferably does not contain fibers having a fiber diameter of 3 μm or less and has been subjected to a needling treatment. It is preferable to use this needle blanket from the viewpoint of load capacity. Here, the fact that the fiber having a fiber diameter of 3 μm or less is not substantially contained means that the fiber having a fiber diameter of 3 μm or less is 0.1 wt% or less of the total fiber weight.

The average fiber diameter of the alumina fiber is preferably 5 to 7 μm. If the average fiber diameter of the alumina fiber is too large, the repulsive force and toughness of the blanket will be lost, and if it is too small, the amount of dust generated in the air will increase, and there is a high probability that fibers with a fiber diameter of 3 μm or less will be contained. Become.

The alumina fiber blanket used in the present invention preferably has an alumina / silica composition ratio (wt%) in the range of 70 to 74/30 to 26 mullite composition. The mulliteization rate is preferably 0.5 to 80 wt%, preferably 0.7 to 75 wt% or more, more preferably 1.0 to 50 wt%, and particularly preferably 1.2 to 30 wt%. .. The mulliteization rate is measured as follows. The measurement sample was crushed in a mortar and measured with an X-ray diffractometer (for example, manufactured by RIGAKU) at a sensitive voltage of 30 kv, a sensitive current of 40 mA, and a speed of 4 ° / min. Read h. Further, the mullite standard substance (for example, NIST Alpha Quartz) is measured under the same conditions, and the peak height h0 of 2θ ₌ 26.3 ° is read. The mullite conversion rate at this time is a value expressed by the following formula.
Mullite conversion rate (%) = h / h ₀ x 100
By setting the mulliteization rate within the above range, it is preferable in that both heat insulating properties and workability can be achieved.

The thickness of the alumina fiber blanket used in the present invention is preferably 6 to 25 mm, more preferably 7 to 13 mm. It is preferable that the alumina fiber blanket has a shrinkage rate (measurement method conforms to JIS R3311) of less than 1% under the condition that the temperature is raised at 5 ° C./min and the temperature is maintained at 1500 ° C. for 8 hours.

The ceramic fiber blanket 3 used in the present invention is a blanket made of alumina, silica, or an amorphous fiber containing alumina, silica, and zirconia as main components.

The thickness of the ceramic fiber blanket 3 used in the present invention is preferably 10 to 60 mm, more preferably 20 to 50 mm.

The above embodiment is an example of the present invention, and the present invention may be in a form other than the illustration. For example, in FIG. 6, eight sheets 10 are sewn to produce an insertion hole covering blanket, but 6 to 10 sheets 10 may be sewn to produce an insertion hole covering blanket. Similarly, about 3 to 5 sheets 10A shown in FIG. 7 may be sewn to produce a blanket covered with an insertion hole . Two or more cuts 10d may be provided on one sheet 10A.

1 Inner lining of continuous quenching furnace 2 Shell iron skin 3 (3A-3D) Ceramic fiber blanket 4 Lining layer 5 Inner surface covering blanket 6 Insertion hole covering blanket 6a Tapered part 6b Cylindrical part 6c Flange part 7,7A Rod 7a Main Rod 7b Oblique rod 8 Nut 9 Washer

Claims (8)

A furnace inner surface coating blanket consisting of a lining layer having a ceramic fiber blanket provided inside the furnace shell iron skin and an alumina fiber blanket having a shot content of 45 μm or more and a shot content of 3% or less covering the inner surface of the lining layer. In the in-furnace lining of a continuous quenching furnace, which is provided with a roll insertion hole that penetrates in and out of the furnace.
An in-furnace lining of a continuous annealing furnace provided with an insertion hole covering blanket made of an alumina fiber blanket having a shot content of 45 μm or more and a shot content of 3% or less, which covers the inner peripheral surface of the roll insertion hole.
At least a part of the roll insertion hole has a tapered shape having a small diameter toward the outside of the furnace.
The insertion hole covering blanket has a tapered portion that overlaps the inner peripheral surface of the tapered shape.
The insertion hole covering blanket is an in-core lining of a continuous annealing furnace, characterized in that 6 to 10 substantially fan-shaped sheets are sewn together. A furnace inner surface coating blanket consisting of a lining layer having a ceramic fiber blanket provided inside the furnace shell iron skin and an alumina fiber blanket having a shot content of 45 μm or more and a shot content of 3% or less covering the inner surface of the lining layer. In the in-furnace lining of a continuous quenching furnace, which is provided with a roll insertion hole that penetrates in and out of the furnace.
An in-furnace lining of a continuous annealing furnace provided with an insertion hole covering blanket made of an alumina fiber blanket having a shot content of 45 μm or more and a shot content of 3% or less, which covers the inner peripheral surface of the roll insertion hole.
At least a part of the roll insertion hole has a tapered shape having a small diameter toward the outside of the furnace.
The insertion hole covering blanket has a tapered portion that overlaps the inner peripheral surface of the tapered shape.
The insertion hole covering blanket is formed by sewing a plurality of substantially fan-shaped sheets together.
Each sheet has an inner arc side, an outer arc side, and a pair of radial sides .
A cut is cut in the radial direction from the middle of the inner arc side .
The opposite sides of the cut are sewn together so as to close the cut.
The in-furnace lining of a continuous annealing furnace, characterized in that the parts along the radial sides of adjacent sheets are sewn together. The in-furnace lining of a continuous annealing furnace according to claim 1 or 2, wherein the insertion hole coated blanket has a flange portion overlapping from the inside of the furnace with the inner surface covering blanket of the furnace around the roll insertion hole. In any one of claims 1 to 3, two or more insertion hole covering blankets are provided in a laminated state, and in the laminated insertion hole covering blanket, the sutured portions thereof are arranged in a non-face-to-face state. The in-furnace lining of the continuous annealing furnace is characterized by this. In any one of claims 1 to 4, a rod erected from the furnace shell iron skin penetrates the ceramic fiber blanket.
The in-furnace lining of a continuous quenching furnace, characterized in that the ceramic fiber blanket, the inner surface-coated blanket and the through-hole coated blanket are held by the shell iron skin by a washer and a nut mounted on the tip of the rod. .. In claim 3,
A rod erected from the furnace shell iron skin penetrates the ceramic fiber blanket.
The rod has a main rod erected perpendicularly to the furnace shell iron skin and an oblique rod connected in the middle of the main rod.
The tip end portion of the main rod penetrates the furnace inner surface covering blanket and the flange portion of the insertion hole covering blanket.
The tip of the slanted rod penetrates the insertion hole covering blanket on the inner peripheral surface of the roll insertion hole.
A ceramic fiber blanket, a furnace inner surface coated blanket, and a flange portion of the insertion hole coated blanket are held by the furnace shell iron skin by a washer and a nut attached to the tip of the main rod.
Inside the furnace of a continuous annealing furnace, the ceramic fiber blanket and the tapered portion of the insertion hole coated blanket are held by the furnace shell iron skin by a washer and a nut mounted on the tip of the inclined rod. Lining. The in-furnace lining of the continuous annealing furnace according to claim 5 or 6, wherein each sheet constituting the insertion hole covering blanket is held by the rod, the washer and the nut on the shell iron skin. .. A continuous annealing furnace provided with the in-core lining according to any one of claims 1 to 7.

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