JP7196661B2 - CONTINUOUS CASTING APPARATUS FOR THIN-WALLED SLIP AND CONTINUOUS CASTING METHOD FOR THIN-WALLED SLIP - Google Patents

Description

The present invention relates to a continuous casting apparatus for thin cast slabs and a continuous casting method for thin cast slabs.

From the standpoint of process and energy savings, the development of a technology for producing thin plates close to the final product at the casting stage, that is, near net shape continuous casting, is underway. Among these methods, the so-called continuous strip casting method is known as an effective near-net-shape continuous casting method for thin plates. The strip continuous casting method is a near-net-shape continuous casting method in which molten metal and mold rolls (or belts) are brought into direct contact with each other to solidify and continuously cast to a casting thickness of about 0.1 to 10 mm (Non-Patent Document 1). Hereafter, it will be referred to as "continuous casting of thin cast slab". A twin roll continuous casting method, a single roll continuous casting method, a twin belt continuous casting method, a single belt continuous casting method, and the like are known as continuous casting methods for thin cast slabs.

In the continuous casting of thin cast slabs using a twin-roll type (also referred to as a twin-drum type) continuous casting apparatus, as shown in FIGS. A thin cast piece 5 is cast by supplying molten metal to the pool. A single roll continuous casting method uses one roll, and several types of methods have been proposed. In the twin-belt continuous casting method, as shown in FIG. 4, a thin cast strip 5 is cast by supplying molten metal to a pool of molten metal partitioned by a pair of belts 10 rotating in opposite directions. there is In the single-belt continuous casting method, one belt is used as a mold, and development for practical use of high-Mn, high-strength carbon steel is underway (Non-Patent Document 1). In the following, among the continuous casting methods for thin-walled slabs, a twin-roll continuous casting apparatus will be described as an example.

In the continuous casting of thin cast slabs by a twin roll type continuous casting apparatus, as shown in FIG. is the thickness of the thin cast slab to be cast. Fixed dams 2 (also called side dams) are pressed against both ends of a roll 1 to form a pool 3 of molten metal. A pair of solidified shells 23 formed along the peripheral surfaces of the rolls are crimped at the nearest portion (gap minimum portion 20) between the rolls to form a slab.

Patent Literature 1 discloses a twin-roll continuous casting facility that includes a hoop material that descends in synchronism with the rolls, and guide rolls and guide members that guide the hoop material. Hoops prevent the formation of hot water and solidified shells between the side dams (fixed dams) and the water-cooled drums (rolls). A thin metal plate (thin cast piece) is formed by casting a hoop material at both ends.

Patent Literature 2 discloses a twin roll continuous casting method in which a band-shaped or linear consumable material is continuously supplied downward to both ends of the molten metal through side seal plates (fixed weirs). Since the consumable material moves together with the solidified shell, the movement resistance of the solidified shell is small, and since the amount of rubbing of the solidified shell against the side seal plate is small, the wear of the side seal is small, and the downward movement of the solidified shell is performed smoothly. and

JP-A-58-163554 JP-A-64-87043

Handbook of Iron and Steel, 5th Edition, Vol. 1, Ironmaking and Steelmaking, pp. 456-457

Thin-walled slabs cast by continuous casting of thin-walled slabs are weak in mechanical strength and fragile after being cast. Therefore, as shown in FIG. 5, the thin cast strips pulled out from the pair of rotary molds 31 form loops so as not to be subjected to tensile stress and are supported by the first pinch rolls 14 . Despite this careful handling, breakage can occur if the tension on the slab is exceeded. A minimum tension of about 10 N/mm ² is applied between the first pinch roll 14 and the inline rolling mill 15 . In particular, tension is most likely to be applied to the ends of the plate due to meandering, etc., and there are many cases where the plate breaks from the ends during transportation.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a continuous casting apparatus for thin-walled slabs and a continuous casting method for thin-walled slabs, which can prevent breakage of cast slabs in continuous casting of thin-walled slabs.

That is, the gist of the present invention is as follows.
A pair of rotating rolls or a pair of belts are hereinafter collectively referred to as a "pair of rotating molds".
[1] Having a pair of rotating molds and fixed weirs in contact with both ends of the rotating molds,
By forming a pool of molten metal surrounded by a rotating mold and a fixed weir above the minimum gap portion of the pair of rotating molds, supplying molten metal into the pool of molten metal, and rotating the rotating molds, A continuous casting apparatus for thin-walled slabs for producing thin-walled slabs via the minimum gap portion,
a metal strip supply device and a metal strip through-hole penetrating through the fixed weir, one opening of the metal strip through-hole opening toward the metal strip supply device; The other opening opens toward the top of the gap minimum portion within the molten metal pool, and the metal strip feeder feeds the metal strip directly above the gap minimum portion through the metal strip through-holes. supply and
The minimum gap portion is a portion where the distance between the pair of rotational molds is the smallest among the pair of rotational molds,
The term "directly above the minimum gap portion" is characterized in that the height direction distance between the upper end of the outlet opening and the minimum gap portion is within a range of 10 times or less of the gap of the minimum gap portion. Continuous casting equipment for thin cast slabs.

[ 2 ] A continuous casting method for thin cast slabs using the thin cast slab continuous casting apparatus according to [1 ] ,
A continuous casting method for thin cast slabs, wherein the metal strip supplied by the metal strip supply device is any one of a metal wire rod, a rectangular rod, a pipe, and a stranded wire.
[ 3 ] The metal strip supplied by the metal strip supply device is a solid strip having an outer diameter equal to or smaller than the gap at the minimum gap portion. Continuous casting method for thin-walled slabs.
[ 4 ] Continuous casting of thin cast strips according to [ 2 ] or [ 3 ], wherein the metal strip supplied by the metal strip supply device has the same composition as the molten metal supplied to the molten metal pool. Method.

In the continuous casting of thin cast slabs, the present invention provides a metal strip through-hole that penetrates a fixed weir, provides an exit opening of the metal strip through-hole directly above the minimum gap portion, and places the metal strip into the metal strip. By supplying the molten metal into the pool near the minimum gap portion through the through-hole, the metal strip is arranged at the width direction end of the cast thin cast slab, so it is possible to prevent the cast slab from breaking. Become.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the condition of twin roll continuous casting to which this invention is applied, (A) is a perspective view, (B) shows front sectional drawing. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the situation of twin roll continuous casting to which the present invention is applied, (A) is a front cross-sectional view along the AA arrow, (B) is a side cross-sectional view along the BB arrow, and (C) is a C- C arrow plane cross-sectional view, (D) is a DD plane cross-sectional view, and (E) is an EE arrow plane cross-sectional view. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the state of twin roll continuous casting to which the present invention is applied, where (A) is a front cross-sectional view and (B) to (D) are cross-sectional views taken along the line AA, showing the cross-sectional shape of a metal strip; However, (B) is a wire rod with a circular cross section, (C) is a pipe rod, and (D) is a rectangular rod. 1 is a perspective view showing a state of twin-belt continuous casting to which the present invention is applied; FIG. 1 is a conceptual diagram showing twin-roll continuous casting with an in-line rolling mill; FIG. 1 is a front cross-sectional view showing a state of twin roll continuous casting to which the present invention is applied; FIG. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing the situation of twin roll continuous casting to which the present invention is applied, (A) is a front cross-sectional view, (B) is a BB arrow plane cross-sectional view, and (C) is a CC arrow plane cross-section. Figure shows. FIG. 2 shows a front cross-sectional view showing the situation of twin roll continuous casting to which the present invention is applied.

A first embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG.
The continuous casting apparatus for thin cast slabs to which the present invention is directed is a twin-roll continuous casting apparatus using a pair of rotating rolls (see FIG. 1) or a twin-belt continuous casting apparatus using a pair of belts (see FIG. 1). 4). A pair of rolls 1 or belts 10 are rotated to form a solidified shell 23 on the rolls 1 or belts 10 while continuously casting a thin cast piece 5. They are collectively referred to as "a pair of rotating molds 31". A pair of rotational molds 31 have their surfaces close to each other from top to bottom, forming the gap minimum portion 20 at the closest portion. An example of a twin-roll continuous casting apparatus will be described below with reference to FIGS.

The continuous casting apparatus for thin cast slabs further has fixed weirs 2 in contact with both ends of the rotary molds 31 (rolls 1). A molten metal pool 3 surrounded by 2 is formed. When the molten metal is supplied from the ladle 12 through the tundish 13 into the molten metal pool 3, the molten metal solidifies at the portion in contact with the rotary mold 31 to form a solidified shell 23. By rotating the rotary molds 31 in mutually opposite directions, the solidified shells 23 formed on the surfaces of the rotary molds 31 move together with the rotary molds 31, and the solidified shells 23 on the surfaces of both the rotary molds 31 are crimped at the minimum gap portion 20. As a result, a thin cast strip 5 is formed, and the thin cast strip 5 is discharged downward from the minimum gap portion 20 . The formed thin cast strip 5 is rolled in an in-line rolling mill 15 via a first pinch roll 14 and wound up by a winder 17 via a second pinch roll 16 .

As described above, the thin cast slab 5 cast by continuous casting of thin cast slabs has extremely low tensile strength after casting and is fragile. Therefore, as shown in FIG. 5, the thin cast slab 5 pulled out from the pair of rotary molds 31 has a slack portion between the minimum gap portion 20 and the first pinch roll 14, and unintended tensile stress is applied to the thin cast strip 5. It is supported so that it does not hang over the slab. Despite this careful handling, breakage can occur if the tension on the slab is exceeded. A minimum tension of about 10 N/mm ² is applied between the first pinch roll 14 and the inline rolling mill 15 . Therefore, tension is most likely to be applied to the ends of the plate due to meandering, etc., and there are many cases where the plate breaks from the ends during transportation.

It is expected that fractures can be reduced if both ends of the thin cast slab 5 have a certain tensile strength. However, as described in Patent Document 1, if a hoop material is supplied from the upper part of the molten metal pool and both ends of the thin cast slab are cast with the hoop material, the following problems arise. That is, the hoop material needs to be wider than the pool of molten steel in order to function as a fixed weir, and this width is significantly larger than the thickness of the thin cast slab. , which causes a decrease in manufacturing yield. Furthermore, in order to transform the hoop material into a U shape, it is necessary to deform the hoop while feeding it in a substantially straight line. There is a high possibility that the contact hoop will wrinkle and hot water will be poured. On the other hand, when the present invention is applied to prevent the molten metal from entering the portion that is cast with the hoop material, the cast piece portion caused by the molten metal and the cast piece portion caused by the hoop material do not form a good connection, Inability to provide sufficient support when the slab is placed in tension after casting.

Further, the invention described in Patent Document 2 continuously supplies the consumable material downward to both ends of the molten metal through side seal plates (fixed weirs). The consumable material is interposed between the side seal and the solidified shell and moves with the solidified shell, thereby reducing the movement resistance of the solidified shell and reducing the wear problem of the side seal (ibid., p. 2). See upper right column). In order to exhibit such an effect, it is necessary to supply the consumable material from the upper part of the molten metal pool. However, if the consumable material is supplied from the upper part of the molten metal pool, the strength of the consumable material decreases due to the thermal effect of the molten metal, and from the viewpoint of preventing breakage due to the tension of the cast slab after casting, the slab cannot be sufficiently supported. There is a problem that there is no

Therefore, in the present invention, it was conceived to attach metal strips 7 as reinforcing materials to both ends of the thin cast piece 5 . Here, the metal strip 7 is made of metal and has a long shape. The cross-sectional shape of the metal strip 7 may be circular (including elliptical), rectangular (square, rectangular), tubular, or stranded wire. However, the metal strip 7 is not inserted into the molten metal pool from above, but rather, as shown in FIG. is aligned with the remaining position, and supplied through the fixed weir 2 . Therefore, the continuous casting apparatus for thin cast slabs of the present invention has a metal strip supply device 6 and further has a metal strip through-hole 19 penetrating through the fixed weir 2. The metal strip through-hole 19 is One opening opens toward the metal strip supply device 6 , and the other opening (outlet opening 21 ) opens in the molten metal pool 3 just above the minimum gap portion 20 . The metal strip 7 can be supplied from the metal strip supply device 6 through the metal strip through-hole 19 directly above the minimum gap portion 20 in the molten metal pool 3 .

As shown in FIG. 2 , the metal strip 7 introduced into the metal strip through-hole 19 is supplied from the outlet opening 21 into the molten metal pool 3 . The metal strip 7 supplied into the molten metal pool 3 directly above the minimum gap portion 20 is formed on the molten metal in the molten metal pool 3 and on the surface of the rotating mold immediately after entering the molten metal pool 3 from the outlet opening 21. contact with the solidified shell 23 (FIG. 2(D)). As the molten metal interposed between the metal strip 7 and the solidified shell 23 solidifies, the metal strip 7 and the solidified shell 23 are bonded together. Both the metal strip 7 and the solidified shell 23 are introduced into the minimum gap portion 20 as the rotary mold 31 (roll 1) rotates. The solidified shells 23 formed on the respective surfaces of the pair of rotating molds 31 are brought into contact with each other at the minimum gap portion 20 and crimped. In the thin cast strip 5 guided downward from the minimum gap portion 20, the metal strip portion (the metal strip 7' welded to the plate) constitutes the width direction end of the thin cast strip 5 (Fig. 2 (E)).

The metal strip 7 is made of the same kind of metal as the thin cast piece 5 to be cast. If the molten metal supplied to the molten metal pool 3 is molten steel and the thin cast slab 5 is a steel cast slab, steel is also used as the metal strip 7 . On the side where the metal strip 7 contacts the molten metal in the molten pool 3, the metal strip 7 is welded to the solidified shell 23 as the molten metal solidifies. Since the contact side) is not heated to the extent that the metal strip 7 is melted, most of the metal strip 7 remains and the required tensile strength can be obtained.

The metal strip 7 introduced into the molten metal pool 3 from the metal strip through-hole 19 is pulled out from the minimum gap portion 20 by the rotation of the rotary mold 31. It is not necessary to apply a force to push the metal strip member through hole 19 into the metal strip member 7 . Therefore, as shown in FIG. 1, the metal strip supply device 6 may be provided with the metal strip 7 wound up and stored. 19, it will be drawn into the pool of molten metal as the rotary mold 31 rotates.

Since the widthwise ends of the cast thin cast slab 5 are composed of metal strips (metal strips 7' welded to the plate), compared to ordinary thin casts that do not have metal strips at their ends, , the strength of the width end portion is increased, and there is no fear of plate breakage due to tension, so it is possible to apply more tension to the plate material than before. Since tension can be applied to the cast thin cast slab 5, meandering detection and tension control can be facilitated, and conveyance and plate thickness can be stabilized.

In the present invention, the exit opening 21 of the metal strip through-hole 19 is provided directly above the minimum gap portion 20 . As a result, the metal strip 7 supplied from the outlet opening 21 into the pool 3 of molten metal immediately comes into contact with the solidified shell 23 and the molten metal in the pool 3 of molten metal. Since the metal strip 7 supplied into the molten metal pool 3 reaches the gap minimum portion 20 in a short time, the time during which the metal strip 7 is exposed to the high temperature of the molten metal before reaching the gap minimum portion 20 is It is short and can minimize material change of the metal strip due to high temperature exposure. Therefore, in the present invention, the height direction distance between the outlet opening upper end 22 and the minimum gap portion 20 is preferably 10 times or less the gap of the minimum gap portion 20 . On the other hand, if the outlet opening upper end 22 is too low with respect to the gap minimum portion 20, the distance between both the solidified shells 23 formed in the pair of rotary molds 31 is too narrow. The ends of the slab cannot be properly connected. Therefore, the height direction distance between the outlet opening upper end 22 and the minimum gap portion 20 is preferably 1.0 times or more the gap of the minimum gap portion 20 .

As described above, the cross-sectional shape of the metal strip 7 may be circular (including elliptical), rectangular (square, rectangular), cylindrical, or stranded wire. If the cross section is circular (including elliptical), the metal strip 7 can be called a wire. If the cross section is rectangular (square, rectangular), the metal strip 7 can be called a rectangular member. If the cross section is cylindrical, the metal strip 7 can be called a tube. If the cross-section is other than cylindrical or stranded, it can be called a "solid strip".

FIG. 3 shows planar cross-sectional shapes along the AA cross section in FIG. FIG. 3(B) shows a case where the metal strip 7 is a solid wire with a circular cross section, FIG. 3(C) shows a case where the metal strip 7 is a tube with a cylindrical cross section, and FIG. This is the case where the strip material 7 is a rectangular material with a rectangular cross section (the short side of the rectangle is arranged in the slab thickness direction).

When the metal strip 7 is a solid strip (Fig. 3(B)), the outer diameter of the metal strip 7 in the slab thickness direction is equal to or less than the gap of the minimum gap portion 20. is preferable. This allows the metal strip 7 to easily pass through the minimum gap portion 20 . The thickness of the thin cast strip 5 pulled out from the minimum gap portion 20 is equal to the gap of the minimum gap portion 20 . Therefore, when the outer diameter of the metal strip 7 in the slab thickness direction is smaller than the gap of the minimum gap portion 20, when the drawn thin slab 5 is rolled by the in-line rolling mill 15, the plate thickness after rolling is By making the outer diameter equal to or larger than the outer diameter of the metal strip 7, the metal strip 7 portion is not rolled down in the in-line rolling mill, so it is not necessary to provide an excessive rolling-down force of the in-line rolling mill, which is preferable. . On the other hand, if a sufficient rolling force can be applied by an in-line rolling mill, the thickness of the metal strip 7 may be made equal to the thickness of the slab at the time of casting, and the strip may be drawn by in-line rolling.

When the metal strip 7 is a tube (FIG. 3(C)) or a stranded wire, the cross-sectional shape can be easily deformed when the metal strip 7 portion of the thin cast piece 5 is rolled down by the in-line rolling mill 15. Therefore, it is easy to make the plate thickness after rolling smaller than the outer diameter of the metal strip 7 even when rolling by the in-line rolling mill 15 . For the same reason, when the metal strip 7 is a pipe material or a stranded wire, even if the outer diameter of the metal strip 7 in the thickness direction of the cast slab is larger than the gap of the minimum gap portion 20, the metal strip 7 does not move when passing through the minimum gap portion. The strip material is easily deformed and can be passed through.

The metal strip 7 supplied by the metal strip supply device 6 preferably has the same composition as the molten metal supplied to the molten metal reservoir 3 . As a result, when the cast thin cast piece 5 is used as a plate material, it can be used without trimming the ends of the metal strip portion. On the other hand, if the end portion is trimmed in a post-process, the composition of the metal strip 7 can be made different from the composition of the molten metal (the composition of the thin casting).

The inner diameter of the metal strip through-hole 19 is preferably in the range of 1.002 to 1.2 times the outer diameter of the metal strip 7 passing through it. If it is 1.002 times or more, it corresponds to a clearance fit of the shaft, and the metal strip 7 can pass through smoothly. On the other hand, if it exceeds 1.2 times, the molten metal may enter the gap between the hole and the metal strip 7 and cause supply obstruction. When the outer diameter of the metal strip 7 is equal to the gap of the minimum gap portion 20, the inner diameter of the metal strip through hole 19 is in the range of 1.002 to 1.2 times the gap of the minimum gap portion 20. It is preferable to be in

FIG. 4 shows the case where the present invention is applied when the continuous casting apparatus for thin cast slabs is a twin-belt type continuous casting apparatus. The twin-belt continuous casting apparatus shown in FIG. 4 has a pair of belts 10, each belt 10 being held by rolls (9a, 9b, 9c). Fixed weirs 2 are provided at both ends of the pair of belts 10 , and the pair of belts 10 and the fixed weirs 2 form a pool 3 of molten metal. The belt 10 is guided from the outside of the molten metal pool 3 by a belt guide and water cooling device 11 at the molten metal pool 3 portion. A pair of belts 10 form a pair of rotating molds 31 by rotating the belts 10 downward in the molten metal pool 3 . The solidified shell formed on the surface of the belt 10 descends together with the belt 10, and both the solidified shells are pressed against each other at the gap minimum portion, and discharged downward as a thin cast piece 5.例文帳に追加The fixed weir 2 has a metal strip through-hole 19, and the metal strip 7 delivered from the metal strip feeder 6 is guided to the pinch roll 8 and guided into the metal strip through-hole. The behavior of the metal strip 7 guided into the molten metal pool 3 from the outlet opening of the metal strip through-hole is as described above for the twin-roll continuous casting apparatus.

A second embodiment of the present invention will be described below. The second embodiment has a pair of rotating molds 31 and fixed weirs 2 in contact with both ends of the rotating molds 31, and the rotating molds and the fixed weirs are placed above the minimum gap portion 20 of the pair of rotating molds. 2 is formed, molten metal is supplied into the molten metal pool 3, and the rotating mold is rotated to produce a thin cast piece 5 via the minimum gap portion 20. A continuous strip casting apparatus further comprising a metal strip supply device 6, a metal strip through-hole 19 passing through the fixed weir 2, and attachment means for attaching the metal strip 7 to the end of the thin cast strip 5. 40 , one opening of the metal strip through-hole 19 opens toward the metal strip feeder 6 , and the other opening (outlet opening 21 ) is downstream of the minimum gap portion 20 . The metal strip supply device 6 supplies the metal strip 7 to the thin cast strip 5 downstream of the minimum gap portion 20 through the metal strip through-hole 19, and the adhesion means 40 The thin cast strip continuous casting apparatus is characterized in that a metal strip 7 supplied by a material supply device 6 is adhered to the thin cast strip 5 .
A continuous casting apparatus for thin cast slabs to which the second embodiment is directed is a twin roll type continuous casting apparatus using a pair of rotating rolls 1 as a pair of rotary molds 31 (see FIG. 1(A)), Alternatively, it is a twin-belt type continuous casting apparatus using a pair of belts 10 (see FIG. 4).

The second embodiment will now be described with reference to FIGS. 6 to 8, taking the case of a twin-roll continuous casting apparatus as an example.
The twin-roll continuous casting apparatus of the second embodiment is characterized in that the metal strip 7 is supplied to the downstream side of the minimum gap portion 20, and the attaching means 40 for attaching the metal strip to the end of the thin cast slab. However, it differs from the twin-roll continuous casting apparatus of the above-described embodiment in that the fixed weir 2 is provided with, for example, a pressing roll 41 (pressing device 42).

In the second embodiment, metal strips 7 are attached as reinforcements to both ends of the thin cast piece 5 on the downstream side of the minimum gap portion. At this time, the metal strip 7 does not pass through the molten metal pool 3 . Since the metal strip 7 does not pass through the molten metal pool 3, the reduction in the strength of the metal strip 7 due to the heat of the molten metal is suppressed. Therefore, even if tension is applied to both ends of the thin cast piece 5 after casting, the second embodiment can more reliably prevent breakage of the thin cast piece 5 than the first embodiment.

The twin-roll continuous casting apparatus of the second embodiment has a metal strip through-hole 19 penetrating through the fixed weir 2, and one opening of the metal strip through-hole 19 is the metal strip feeder. 6 and the other opening (outlet opening 21 ) opens downstream of the gap minimum 20 , preferably just below the gap minimum 20 . Directly below the minimum gap portion 20 means the range until 5 seconds have passed when the casting speed is 1 m/s, specifically, the range approximately 1000 mm downstream from the minimum gap portion 20 .

In a preferred embodiment, as shown in FIG. 7, the outlet opening 21 of the metal strip through-hole 19 opens directly below the minimum gap portion 20, so that the metal strip 7 is supplied directly below the minimum gap portion 20. be. Since the sensible heat of the thin cast piece 5 can be sufficiently utilized immediately below the minimum gap portion 20 , the metal strip 7 can be crimped by heating using the sensible heat of the thin cast piece 5 .

The twin-roll continuous casting apparatus of the second embodiment has a metal strip feeder 6 as shown in FIG. It can be supplied downstream of the minimum portion 20 . In the preferred embodiment shown in FIG. 7, the metal strip 7 introduced into the metal strip through-hole 19 is fed from the outlet opening 21 directly below the gap minimum portion 20 . The metal strip 7 supplied directly below the minimum gap portion 20 comes into contact with the thin cast piece 5 .

In the twin roll continuous casting apparatus of the second embodiment, the fixed weir 2 is provided with pressure rolls 41 as attachment means 40 for attaching the metal strip 7 to the thin cast slab 5 . The pressing roll 41 is provided downstream of the outlet opening 21 . Therefore, when the metal strip 7 is supplied directly below the minimum gap portion 20 , the metal strip 7 is pressed against the end portion of the thin cast strip by the pressing rolls 41 . Since the temperature of the thin cast strip 5 is high immediately below the minimum gap portion 20 , the metal strip 7 is pressed against the edge of the thin cast strip 5 by the presser roll 41 , so that the metal strip 7 is heated to the end of the thin cast strip 5 . It is crimped to the part.

In the above-described second embodiment, a case has been described in which the metal strip is crimped to the end of the thin cast strip by utilizing the temperature of the thin cast strip immediately below the minimum gap portion. However, it is not limited to this. For example, the adhesion means 40 includes a heating device 43 for heating both ends of the thin cast strip, and a metal strip material attached to the end portion of the thin cast strip 5 heated by the heating device 43 and arranged downstream of the heating device 43 . A crimping device 42 for crimping 7 may be provided.
Specifically, as shown in FIG. 8, a heating device 43 for heating and heating both ends of the thin cast piece 5 is placed directly above the pressing roll 41 as the crimping device 42 so that the end portion of the thin cast strip 5 can be heated. It is also possible to provide a similar device, heat up the end portion of the thin cast piece 5 until it is slightly melted, and press and weld the metal strip 7 . As a device that can raise the temperature, for example, a torch 44 such as an oxygen torch or a gas torch is assumed (see FIG. 8). Thus, when a device (torch 44) capable of raising the temperature of the end portion of the thin cast strip is provided directly above the pressing roll 41, even if the metal strip 7 is not supplied directly below the minimum gap portion 20, Any position on the downstream side of the minimum gap portion 20 is sufficient. Specifically, even when the metal strip is supplied to a position several tens of meters downstream from the minimum gap portion 20, the metal strip can be attached to the end portion of the thin cast slab.

Also in the second embodiment, as in the first embodiment, the metal strip supplied by the metal strip supply device 6 can be a metal wire, rectangular material, tube, or stranded wire. . Further, when the metal strip supplied by the metal strip supply device 6 is a solid strip, it is preferable that the outer diameter is equal to or smaller than the gap of the minimum gap portion 20 . Furthermore, it is preferable that the metal strip 7 supplied by the metal strip supply device 6 has the same composition as the molten metal supplied to the molten metal pool 3 .

REFERENCE SIGNS LIST 1 roll 2 fixed dam 3 molten metal pool 5 thin cast piece 6 metal strip supply device 7 metal strip 7' metal strip welded to plate 8 pinch roll 9a roll 9b roll 9c roll 10 belt 11 belt guide and water cooling device 12 ladle 13 tundish 14 first pinch roll 15 inline rolling mill 16 second pinch roll 17 winder 19 metal strip through-hole 20 minimum gap 21 exit opening 22 exit opening upper end 23 solidified shell 31 rotary mold 40 attachment means 41 Press roll 42 Crimping device 43 Heating device 44 Torch

Claims (4)

Having a pair of rotating molds and fixed weirs in contact with both ends of the rotating molds,
By forming a pool of molten metal surrounded by a rotating mold and a fixed weir above the minimum gap portion of the pair of rotating molds, supplying molten metal into the pool of molten metal, and rotating the rotating molds, A continuous casting apparatus for thin-walled slabs for producing thin-walled slabs via the minimum gap portion,
a metal strip supply device and a metal strip through-hole penetrating through the fixed weir, one opening of the metal strip through-hole opening toward the metal strip supply device; The other opening opens toward the top of the gap minimum portion within the molten metal pool, and the metal strip feeder feeds the metal strip directly above the gap minimum portion through the metal strip through-holes. supply and
The minimum gap portion is a portion where the distance between the pair of rotational molds is the smallest among the pair of rotational molds,
The term "directly above the minimum gap portion" is characterized in that the height direction distance between the upper end of the outlet opening and the minimum gap portion is within a range of 10 times or less of the gap of the minimum gap portion. Continuous casting equipment for thin cast slabs. A continuous casting method for thin cast slabs using the apparatus for continuously casting thin cast slabs according to claim 1 , comprising:
A continuous casting method for thin cast slabs, wherein the metal strip supplied by the metal strip supply device is any one of a metal wire rod, a rectangular rod, a pipe, and a stranded wire. 3. The thin casting according to claim 2 , wherein the metal strip supplied by the metal strip supply device is a solid strip having an outer diameter equal to or smaller than the gap of the minimum gap portion. A method of continuous casting of pieces. 4. The continuous casting method for thin cast slabs according to claim 2 , wherein the metal strip supplied by the metal strip supply device has the same composition as the molten metal supplied to the molten metal pool.

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