JPH091294A - Mold roll device in twin roll type strip continuous casting equipment and manufacture of mold roll - Google Patents

Abstract

PURPOSE: To facilitate the inserting work of a sheet, to drastically shorten the inserting time of the sheet into a slit by inserting the ceramic-made sheet into the slit between mold rolls, and to further shorten the working time particularlly by using a green sheet as the sheet because the hardening time is unnecessary. CONSTITUTION: At the time of driving a magnetic flux generating device, an alternating magnetic flux is generated so as to pass between the end parts of the mold rolls 1, 2 and in molten metal between both mold rolls 1, 2. Under this state, a strip is continuously produced from the nearest part between both mold rolls 1, 2 by supplying the molten metal between both mold rolls 1, 2 and rotating in the mutually reverse directions inserting both mold rolls 1, 2. In side surface covers 6 fitted to the side end surfaces of the mold rolls 1, 2, the slits 8 are formed, and in each slit 8, the ceramic-made green sheet 9 is inserted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold roll device in a twin roll type thin plate continuous casting facility and a method for manufacturing the mold roll device.

[0002]

2. Description of the Related Art Conventionally, while supplying molten metal between a pair of opposed mold rolls, these mold rolls are rotated in a relative direction so as to sandwich the molten metal, thereby crimping a slab shell formed on the surface of the mold roll. There is a twin roll type thin plate continuous casting facility that continuously draws a slab from the closest part of the mold roll to produce a thin plate.

In the mold roll device of this twin roll type thin plate continuous casting facility, the end face of the mold roll is slidably contacted,
A short-side weir is provided to hold the molten metal supplied, but since the molten metal and the short-side weir contact each other, the end surface of the mold roll and the sliding contact portion of the short-side weir are damaged, and the end surface of the cast piece Damages the product and reduces product retention.

For this reason, Japanese Patent Publication No. 6-503035 proposes a mold roll device which uses electromagnetic force to hold the molten metal in a non-contact manner. That is, as shown in FIG. 5 and FIG. 6, this conventional mold roll device 50 includes a mold roll 51 made of a magnetic material.
Ribs 52 are extended around the ends of the magnetic poles 53, and the magnetic poles 53 are arranged at predetermined positions on the back side of these ribs 52,
The alternating magnetic flux 54 formed between these magnetic poles 53 is transferred to the rib 52.
The molten metal 55 is held by allowing the electromagnetic force generated by the alternating magnetic flux 54 to act in the anti-leakage direction of the molten metal 55 through

However, when the alternating magnetic flux 54 is generated between the magnetic poles 53, the end of the mold roll 51 made of a magnetic material is abnormally heated by electromagnetic induction heating, and the mold roll 51 is worn.

Therefore, as shown in FIG. 5, a large number of slits 56 are formed at the ends of the mold roll 51, and a mixture of ceramic powder and water or alcohol is formed in the slits 56 by using a wire material or the like. Fill each
As a result, the slits 56 are insulated from each other, the alternating magnetic flux 54 is generated between the magnetic poles 53, the end portion of the mold roll 51 is prevented from being overheated, and the wear of the mold roll 51 is prevented.

[0007]

In the conventional mold roll device 50, the slits 56 formed at the ends of the mold roll 51 have a narrow width and a large number of slits 56.
The work of filling each slit 56 with the mixture of the ceramic powder and water or alcohol is troublesome and requires a lot of labor and time.

Further, since the mixture is generally a mixture of ceramic powder and water or alcohol, a waiting time is required until the mixture is cured. Further, when the mold roll device 50 is used, when the mixture is heated and contracts, the mixture may drop out from the slit 56.

Therefore, an object of the present invention is to provide a mold roll apparatus in a twin roll type thin plate continuous casting equipment capable of solving the above problems.

[0010]

Means for solving the problems of the present invention is to provide a pair of mold rolls facing each other, and to supply a magnetic flux between the ends of both mold rolls and between both mold rolls. A magnetic flux generator for passing the molten metal through the molten metal is provided, and by rotating both mold rolls in the relative direction sandwiching the molten metal, a slab is continuously drawn from the closest part of both mold rolls to produce a thin plate. With a mold roll device in a roll type thin plate continuous casting facility, a plurality of slits along the radial direction are formed at the ends of each mold roll, and a ceramic sheet is inserted and fixed in each slit.

The ceramic sheet inserted into each slit along the radial direction of the end of each mold roll is a green sheet. Further, as the ceramics constituting the sheet inserted in each slit along the radial direction of the end portion of each mold roll, a ceramic having a particle diameter of 1 μm or more and 50 μm or less is used.

Further, the magnetic flux generated by the magnetic flux generator is
Between the ends of a pair of mold rolls facing each other, and through the molten metal supplied between both mold rolls, by rotating both mold rolls in the relative direction sandwiching the molten metal, continuous from the closest part of both mold rolls With a mold roll device in a twin roll type thin plate continuous casting equipment for drawing a slab to produce a thin plate, a plurality of radial slits are formed at the end of each mold roll, and a ceramic sheet is formed in each slit. It is manufactured by inserting and fixing.

A ceramic green sheet is inserted into each slit along the radial direction of the end of each mold roll. Furthermore, the particle size of the ceramics is 1
A sheet having a size of not less than μm and not more than 50 μm is formed into a sheet, a plurality of slits along the radial direction are formed at the end of the mold roll, and the sheet is inserted into the slit.

[0014]

In the above means for solving the problems, the magnetic flux generator is driven to pass the magnetic flux between the end portions of both mold rolls and into the molten metal supplied between both mold rolls so that a pair of mold rolls face each other. By holding the molten metal supplied and rotating both mold rolls in the relative direction sandwiching the molten metal, a thin plate is manufactured by continuously pulling out the slab from the closest part of both mold rolls, and the end of each mold roll. Since the ceramic sheet is inserted and fixed in the plurality of slits along the radial direction, the mold roll is insulated and prevented from being heated.

Further, a mold roll device is manufactured by inserting and fixing a ceramic sheet into a plurality of slits along the radial direction at the end of each mold roll.

[0016]

EXAMPLES Examples of the mold roll device in the twin roll type thin plate continuous casting equipment according to the examples of the present invention will be described below.
Describing based on FIG. 1 to FIG. 3, this is a pair of mold rolls 1 and 2 facing each other.
The molten metal 3 supplied between them is rotated in a relative direction so that the thin plate 4 is manufactured by continuously pulling out the slab from the closest part.
A magnetic flux generator 5 is provided for generating an alternating magnetic flux and holding the molten metal 3 supplied between the two.

The magnetic flux generator 5 is for passing the alternating magnetic flux between the ends of the mold rolls 1 and 2 and into the molten metal 3 between the mold rolls 1 and 2, and should be formed as described above. Thus, the molten metal 3 is held in a non-contact manner.

A disk-shaped side cover 6 is attached to the side end surfaces of each of the mold rolls 1 and 2, and a ring-shaped ridge member 7 is formed around the front surface of the side cover 6, and the ridge member 7 is formed. Slits 8 are formed at a predetermined interval and a predetermined width along the radial direction of the mold rolls 1 and 2 from the front face to the rear face of the mold rolls 1, and each of the slits 8 is covered with a ceramic green sheet 9 and a wire or the like. A mold roll device is configured by being used and inserted.

For example, the interval L between each slit 8 is 5.24 mm, which corresponds to every 0.5 °, the width B is 0.5 mm, and the depth F is.
Is formed to be 15 mm, and the thickness of the green sheet 9 is 0.
Green sheet 9 with a thickness of 4 to 0.45 mm
As the material, for example, alumina (aluminum oxide), zirconia (zirconium oxide), magnesia (magnesium oxide), or the like is used, and the particle size is 1 μm or more and 50 μm or less.

The slurry which becomes the green sheet 9 is
3 parts (parts by weight) of polyvinyl butyral (also referred to as PVB) was added to the ceramic powder as a binder, adjusted to 20000 cP with alcohol, and formed into a sheet using a doctor blade forming method.

In the above structure, when the magnetic flux generator 5 is driven, an alternating magnetic flux is generated so as to pass between the ends of the mold rolls 1 and 2 and into the molten metal 3 between the mold rolls 1 and 2. In this state, the molten metal 3 is supplied between the mold rolls 1 and 2, and the mold rolls 1 and 2 are rotated in a relative direction so as to sandwich the mold rolls 1 and 2 so that the thin plate 4 is continuously connected from the closest portion of the mold rolls 1 and 2. Is manufactured.

By the way, even if the magnetic flux generator 5 is driven to generate an alternating magnetic flux, slits 8 are formed in the side covers 6 attached to the side end faces of the mold rolls 1 and 2 made of a magnetic material. Since the green sheet 9 made of ceramics is inserted into the slit 8, the side cover 6 is insulated at a plurality of positions, and therefore, the side cover 6 is not excessively heated and is prevented from being worn. The green sheet 9 is automatically fired by the generation of alternating magnetic flux.

Here, the results of measuring the respective shrinkage rates using 15 different types of test pieces are shown in (Table 1) below. These test pieces (No. 1 to N)
o. 15) is a ceramic material having a grain size of 0.1.
Alumina, zirconia, and magnesia of 5 μm to 50 μm were used to adjust the compounding particle size (Vol%), and 3 parts of polyvinyl butyral was added to each, and the viscosity was 20.
Add alcohol to 000 cP and make it into a sheet using doctor blade molding method.
It was heated at ° C for 2 hours.

[0024]

[Table 1]

From the above (Table 1), it became clear that the sheet using the particles having a particle size in the range of 1 μm to 50 μm had very little shrinkage. In addition, No. 3 and No. 3
The sample No. 15 had a shrinkage rate of 2%, but no problem occurred in actual use.

Further, according to the above-mentioned experiment, when the ratio of ceramics having a particle size of 1 μm exceeds 10%, the shrinkage rate becomes large, and for a sheet having a particle size of 50 μm exceeding 30%, this is smoothly slit. Could not be inserted into.

Here, No. The following (Table 2) shows the results of trying the falling state from the slit when No. 4 (however, the green sheet) was used in an actual machine. In this (Table 2), No. 1 in (Table 1). For comparison with that of No. 4, the results of pre-experimenting three inserts (filler) of A, B, and C under the conditions shown in the table are shown.

That is, each of the three fillers A, B and C uses 100 parts of alumina having a particle size of 0.5 μm as ceramics and 3 parts of polyvinyl butyral as a binder, and Alcohol was added to increase the viscosity. A and B were naturally dried,
For C, it was forced to dry at 150 ° C.

The actual machine condition is a diameter of 1200 mm.
725 slits were formed at the end of the mold roll (made of SUS304) under the same conditions as those shown in the above-mentioned embodiment, the casting speed was 40 m / s, and casting of about 10 tons was performed.
This is the case in 0 minutes.

According to this experiment, with respect to the filling materials A and B, the dropping from the slits started at the same time as the rotation of the mold roll, and finally 70% and 60% dropping respectively, and with respect to the filling material C, Cracks occurred during drying and most of them fell off the slit. On the other hand, N
o. The green sheet of No. 4 finally had a dropout rate of 3%.

[0031]

[Table 2]

From the above (Table 2), alumina was used as the material of the ceramics, and the blending particle size was 90 Vol% for particles having a particle size of 5 μm and 10 Vol% for particles having a particle size of 10 μm.
Add 3 parts of polyvinyl butyral to increase the viscosity to 20000
It was clarified that the drop rate from the slit was extremely small by adding alcohol to form a sheet so as to obtain cP and inserting the sheet into the slit.

Further, since the insert in the slit is in the form of a sheet, it is easy to insert, and therefore the construction time is greatly shortened, and the use of the green sheet also eliminates the need for the drying time.

As described above, according to the embodiment of the present invention, the ceramic green sheet 9 is used as the insert to be inserted into the slit 8 of the side cover 6 attached to the side end faces of the mold rolls 1 and 2. As compared with the case where the filling is dried, the insertion work is easier.

Further, since the green sheet 9 is inserted into the slit without waiting for its curing, the construction time for manufacturing the mold roll device can be greatly shortened as compared with the conventional case.

The green sheet 9 made of ceramics
Is inserted into the slits 8 of the side cover 6 attached to the side end faces of the mold rolls 1 and 2 to insulate the side faces, even if the molten magnetic flux 3 is generated by the magnetic flux generator 5 and the molten metal 3 is held. Magnetic flux is hard to be generated in 6 and the side cover 6
Is not overheated and wear can be suppressed.

In particular, the particle size of ceramics is 1 μm to 5 μm.
When the green sheet 9 having a thickness of 0 μm is used, the green sheet 9 hardly shrinks, so that the green sheet 9 can be prevented from coming off from the slit 8 to protect the mold rolls 1 and 2 for a long time.

In the above-mentioned embodiment, the filling material to be inserted into the slit 8 is the green sheet 9. However, the filling material is not limited to this, and the embodiment of the present invention relates to continuous casting equipment. The filling material to be inserted in may be in the form of a sheet obtained by firing the green sheet 9.

[0039]

As is apparent from the above description, according to the present invention, since the inserts inserted into the slits of the mold rolls facing each other are made of ceramic sheets, a mixture of ceramic powder and water is simply used. Compared to the conventional case of inserting in the slit, the insertion work is easier, and therefore,
The time for inserting the sheet into the slit can be significantly reduced.

Especially when the sheet is a green sheet, no curing time is required, so that the construction time can be further reduced. Also, the grain size of the ceramics is 1 μm
By using the resin having a thickness in the range of ˜50 μm, the sheet hardly shrinks, and therefore the sheet can be prevented from falling out of the slit and the mold roll can be protected for a long term.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of a mold roll device in a twin roll type thin plate continuous casting facility showing an embodiment of the present invention.

FIG. 2 is a partially enlarged view of the side cover of the same.

FIG. 3 is a front view of the main part.

FIG. 4 is a partially enlarged front view of the same.

FIG. 5 is a schematic front view of a conventional mold roll device.

FIG. 6 is a schematic plan view of the same.

[Explanation of symbols]

 1 Mold Roll 2 Mold Roll 3 Molten Metal 4 Thin Plate 5 Magnetic Flux Generator 6 Side Cover 7 Ridge Member 8 Slit 9 Green Sheet

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shoichi Mohri 5-3-8, Nishikujo 5-chome, Konohana-ku, Osaka City, Osaka Prefecture Hitachi Shipbuilding Co., Ltd.

Claims (6)

[Claims] 1. A pair of mold rolls facing each other is provided, and a magnetic flux generator is provided for allowing a magnetic flux to pass between the ends of both mold rolls and into the molten metal supplied between both mold rolls. A mold roll device in a twin roll type thin plate continuous casting facility for continuously manufacturing a thin plate by drawing a slab from the closest part of both mold rolls by rotating the roll in a relative direction sandwiching the molten metal. A mold roll device in a twin roll type thin plate continuous casting facility, wherein a plurality of slits are formed along the radial direction at the end of the roll, and a ceramic sheet is inserted and fixed in each slit. 2. The twin-roll type thin plate continuous casting facility according to claim 1, wherein the ceramic sheet inserted into each slit along the radial direction of the end of each mold roll is a green sheet. Mold roll equipment. 3. The ceramics constituting a sheet inserted into each slit along the radial direction of the end portion of each mold roll has a grain size of 1 μm or more and 50 μm or less. Item 2. A mold roll device in a twin roll type thin plate continuous casting facility according to Item 1. 4. A relative direction in which the magnetic flux generated by the magnetic flux generator is passed between the ends of a pair of mold rolls facing each other and into the molten metal supplied between the two mold rolls, and the two mold rolls sandwich the molten metal. By rotating it to
A method of manufacturing a mold roll device in a twin roll type thin plate continuous casting facility for continuously manufacturing a thin plate by pulling out a slab from the closest part of both mold rolls, along the radial direction at the end of each mold roll. A method of manufacturing a mold roll device in a twin roll type thin plate continuous casting facility, comprising forming a plurality of slits, and inserting and fixing a ceramic sheet into each slit. 5. A mold roll apparatus in a twin roll type thin plate continuous casting facility according to claim 4, wherein a ceramic green sheet is inserted into each slit along the radial direction of the end of each mold roll. Method. 6. A ceramic having a particle size of 1 μm or more is 50.
5. A mold in a twin roll type thin plate continuous casting facility according to claim 4, wherein the mold is formed into a sheet having a thickness of less than or equal to .mu.m, a plurality of slits are formed along the radial direction at the end of the mold roll, and the sheet is inserted into the slit. Roll device manufacturing method.