JPH07112605B2 - Metal strip continuous casting machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal ribbon continuous casting machine for continuously producing metal ribbon directly from a molten metal.

[0002]

2. Description of the Related Art If a metal ribbon can be directly manufactured from molten metal,
It is preferable because the rolling process can be greatly simplified. Figure 7
Is an example of a twin-drum type metal ribbon continuous casting machine described in JP-A-61-27675. The molten metal 6 is poured into a molten metal pool formed by two rotating drums 18a and 18b that rotate in the arrow direction. The molten metal in contact with the rotating drum
The solidified shell is formed by being cooled between the point m and the point n, and the solidified shells formed on 18a and 18b are united at the point n and taken out as the metal ribbon 10. In order to increase the productivity (ton / hour) by this method, the rotary drum must be rotated quickly.
Since the distance between the points is short, the thickness of the solidified shell is insufficient when rotated rapidly, and a metal ribbon having a predetermined thickness cannot be manufactured. Moreover, if the diameter of the rotating drum is increased, the equipment becomes extremely large. Further, in this method, the plate thickness can be changed by changing the distance between the rotary drums 18a and 18b. For this purpose, the side dam is pressed against the drum body end, and in this case, the plate width is different. In order to obtain cast slabs, it is necessary to prepare drums with various body lengths, the equipment cost will be enormous, and the drums must be recombined when the plate width is changed, which is a preferable production mode for operation. Does not mean

FIG. 8 shows an example of a twin-belt type metal ribbon continuous casting machine described in JP-A-59-47047. The molten metal 6 includes pulleys 19a, 19b,
It is poured into the pool of water formed by the endless belt 1 stretched and run on 19c and the endless belt 1'which is stretched and run similarly. Since the back surfaces of the endless belts 1 and 1'are cooled by the cooling devices 12 and 12 ', the molten metal in contact with the endless belts forms a solidified shell and is taken out as a metal ribbon 10 after solidification is substantially completed.
In order to produce a thin metal plate by this method, the distance t between the endless belts 1 and 1'is narrowed. However, if t is made too small by this method, the injection flow of the molten metal causes the endless belt to flow. This damages the endless belt and impairs the surface properties of the metal ribbon 10, which is not preferable. Further, in this method, the side weir is clamped by the belt surface regardless of whether it is a fixed type or a movable type, so that the side weir must be replaced in order to change the plate thickness.

As described above, the twin drum type metal ribbon continuous casting machine can produce a metal ribbon having a thin plate thickness, but it is not easy to obtain high productivity and it is not easy to change the plate width. . On the other hand, the twin belt type metal ribbon continuous casting machine is
For example, by providing a large distance between 19a and 19b in FIG. 8, high productivity can be obtained, but it is not easy to manufacture a thin metal plate and it is not easy to change the plate thickness.

[0005]

DISCLOSURE OF THE INVENTION The present invention is capable of producing a thin metal strip with high productivity, and is capable of changing the thickness and width of a slab without changing the components of the casting machine. A strip continuous casting machine is disclosed.

[0006]

FIG. 1 is a schematic front view showing the entire metal ribbon continuous casting machine. This metal strip continuous casting machine is provided with an endless belt 1 which is inclined between the upper roll 2 and the lower roll 3 and travels in the direction of arrow 5, for example, and an upper roll 2'and a lower end which are arranged facing each other. A long side wall of the upper wide mold is formed by the endless belt 1'which is inclined with respect to the roll 3'and runs in the direction of the arrow 5 '. In the present invention, the endless belts 1 and 1'are tensioned by tension rolls 9 and 9 ', for example. Reference numerals 4 and 4 ′ are side weirs, which are wide and wide along the running paths of the endless belts 1 and 1 ′ and are sandwiched by the endless belts to form short side walls of the wide upper mold. The molten metal 6 is poured into this upper wide mold, but since the back surface of the endless belt is cooled by the cooling pads 12 and 12 ', solidified shells 8 and 8'are formed in the mold, and the solidified shell is formed at the lower end of the mold. The metal strips 8 and 8'are united with each other. When the solidified shells 8 and 8'are united, the lower rolls 3 and 3'press the solidified shells via the endless belts 1 and 1 '. By this pressurization, the thickness and cross-sectional shape of the metal ribbon 10 are adjusted.

FIG. 2 is a plan view of the continuous metal strip casting machine of FIG. 1, in which the side dams 4 and 4'are inserted into the belts 1 and 1'in order to obtain a slab having a relatively small plate width. Has become. On the other hand, FIG. 3 shows a state in which a slab having a relatively large plate width is being cast, and the side dams 4 and 4'are located near the end faces of the belts 1 and 1 '. As described above, in this casting machine, the plate width can be easily changed by moving the side dams 4 and 4'in the plate width direction.

Further, in this casting machine, the plate surface shape of the upper wide mold formed by the endless belts 1 and 1'and the corresponding side surface shapes of the side dams 4 and 4'are arcuate shapes. It is also possible to change the plate thickness without replacing. This will be described in detail below.

FIG. 4 shows a case where a casting machine of the present invention is used to cast a sheet having a thickness larger than that of the state shown in FIG. 1, but the endless belt 1 (1 ') and the upper guide roll 2 (2'). , The lower guide roll 3 (3 ') and the cooling device 12 (12') are integrally rotating around the center of curvature of the belt surface, and as a result, no gap is formed between the lower guide roll 3 (3 ') and the side weir. The thickness of the slab can be changed. Since this casting machine has such a function, it is possible to cast slabs with different plate thickness without replacing the side dam, and it is possible to continuously change the plate thickness during casting. It is possible.

Generally, when the side surface of the side weir has a curved shape other than a circular arc, it is impossible to completely fill the gap with the side weir generated when the plate thickness is changed only by rotating the rigid body or moving the rigid body. , It is not established as a continuous casting machine with variable plate thickness. Further, as the side surface shape of the side weir whose thickness can be changed without exchanging the side weir, there is a linear shape (first-order expression) in addition to an arc shape (second-order expression). In the case of a straight line shape, it is not necessary to rotate the casting machine rigidly, and it is easier to change the plate thickness, but it becomes impossible to press the belt against the cooling device due to the belt tension, and the static pressure of the melt is particularly low. Since it becomes difficult to use pad cooling with high cooling ability in the vicinity of the meniscus, the risk of belt meltdown increases, and it is difficult to obtain a slab with high plate thickness accuracy because the belt is also easily buckled due to temperature deviation. Become. On the other hand, in the case of an arc shape, it is possible to press the belt against the cooling device by the belt tension,
Pad cooling can be adopted over the entire surface, and stable casting is possible without the risk of belt melting damage. Further, since the belt itself has a curvature, buckling due to temperature deviation is less likely to occur, and a slab with high plate thickness accuracy can be obtained.

In order to construct a casting machine in which the plate width and the plate thickness can be changed, the following two methods can be considered. (1) The side dams 4, 4'are movable in the plate width direction, and the endless belts 1, 1 ', the guide rolls 2, 2', 3, 3 ', and the belt cooling devices 12, 12' are integrated into a belt surface. A metal ribbon continuous casting machine configured to be rotatable around a central axis of curvature. (2) The side dams 4, 4'are movable in the casting direction and the plate width direction, and the endless belts 1, 1 ', the guide rolls 2,
A metal ribbon casting machine in which 2 ', 3, 3'and belt cooling devices 12, 12' are integrally configured so as to be movable in the thickness direction of the slab and rotatable about the central axis of the belt surface curvature.

The method (1) is shown in FIG. 4, in which the side weir only moves in the plate width direction when the plate width is changed, and when the plate thickness is changed, a casting machine other than the side weir is used. The main body rotates rigidly around the central axis of the belt surface curvature to form a new wide mold. In this case, although the kissing point moves up and down as the plate thickness changes, there is an advantage that the mechanism of the movable part of the casting apparatus becomes simple.

The method (2) is shown in FIG. 5. When the plate thickness is changed, the casting machine body hardly moves in the casting direction, and the side dam moves in the casting direction to change the plate thickness. It will be. In this case, the kissing point does not move, but the other casting machine bodies have to perform rigid body movement in the plate thickness direction and rigid body rotation around the central axis of the lower guide roll 3 (3 '). There is a drawback that the mechanism of is complicated.

FIG. 6 shows another structure of the continuous metal strip casting machine of the present invention. The continuous casting machine shown in FIG. 6 has a cooling device 12 so that the cooling region of the slab 10 by the endless belts 1 and 1'can be expanded below the lower guide rolls 3 and 3 '.
b, 12b 'and guide rolls 11, 11' are provided. Although it is possible to slightly press the slab with the guide rolls 11 and 11 ', the endless belts 1 and 1'
It is the lower guide rolls 3, 3'that press-compress the solidified shells 8, 8'generated above. Therefore, during steady work except when the casting is started, the side below the lower guide rolls 3, 3 ' Weirs are basically not required.

As described above, by expanding the cooling region of the slab 10 by the endless belts 1 and 1 ', it is possible to expand the selection range of the cooling rate for forming the material of the slab and at the time of starting the casting. It is possible to prevent such an accident that the slab breaks out even during unstable operation. Further, in this embodiment, when it is not necessary to rapidly cool the slab 10 after casting, the guide roll 1
The endless belts 1, 1 ′ are slabs 1 below the lower guide rolls 3 and 3 ′ by increasing the distance between the slabs 1 and 11 ′.
It suffices not to touch 0.

[0016]

EXAMPLE 1 The structure as shown in FIG. 1 has a belt thickness of 1.5 mm, a belt width of 2000 mm, upper guide rolls 2 and 2 ', lower guide rolls 3 and 3', and cooling devices 12 and 12 '. Using a casting machine in which the shape of the belt 1, 1'constituted by is a circular arc with a radius of curvature of 3000 mm, molten steel having a composition of 0.1% C steel and a temperature of 1590 ° C. is poured into the pool to obtain a wall thickness of 4 .6 m
A metal ribbon having a sheet width of m and a plate width of 1500 mm was produced at a casting speed of 107 mpm. At this time, the height of the molten metal surface from the kissing point to the meniscus is 1750 mm, and the contact length between the belt and the pool is approximately 1940 mm. Under the same conditions,
By reducing the distance between the side dams 4 and 4 ', a slab having a plate thickness of 4.6 mm and a plate width of 900 mm could be cast. Next, in order to cast a slab having a large plate thickness, the upper guide roll 2 (2 '), the lower guide roll 3 (3'), and the cooling device 12 (12 ') are integrated into a belt while the side dam is fixed. It is possible to produce molten steel with a plate thickness of 25 mm at a casting speed of 5.2 mpm by pouring molten steel around the center axis of surface curvature by a rigid rotation in the direction of expanding the gap at the kissing point by 1.84 °. It was

Embodiment 2 With the structure as shown in FIG. 1, the belt thickness is 1.5 mm, the belt width is 2000 mm, the upper guide rolls 2 and 2 ', the lower guide rolls 3 and 3', and the cooling devices 12 and 12 '. Using a casting machine in which the shape of the belts 1 and 1'constituting is an arc shape with a radius of curvature of 3000 mm, molten steel having a 0.1% C steel composition and a temperature of 1590 ° C. is poured into a basin to obtain a wall thickness of 4 ．
A metal ribbon of 6 mm and a plate width of 1500 mm was produced at a casting speed of 107 mpm. At this time, the height of the molten metal surface from the kissing point to the meniscus is 1750 mm, and the contact length between the belt and the pool is approximately 1940 mm. Under the same conditions, it was possible to cast a slab having a plate thickness of 4.6 mm and a plate width of 900 mm by reducing the distance between the side dams 4 and 4 '. Next, in order to cast a slab having a large plate thickness, the side dam is lowered by 95.6 mm in the casting direction, and the upper guide roll 2 (2 '), the lower guide roll 3 (3'), and the cooling device 12 are used.
(12 ') is moved as a unit in the plate thickness direction, and further, a rigid body is rotated about the lower guide roll 3 (3') to fill the gap with the side weir and inject molten steel at 5.2 mpm. It was possible to manufacture a slab with a plate thickness of 25 mm at a casting speed of.

[0018]

By using the metal strip continuous casting machine of the present invention, it is possible to stably produce metal strips of various widths and thicknesses with good quality and high productivity. Become.

[Brief description of drawings]

FIG. 1 is a front view showing the basic structure of a metal strip continuous casting machine of the present invention.

FIG. 2 is a plan view showing a state where a slab having a relatively small plate width is cast by the metal strip continuous casting machine of the present invention.

FIG. 3 is a plan view showing a state where a slab having a relatively large plate width is being cast by the metal strip continuous casting machine of the present invention.

FIG. 4 is a front view of the metal strip continuous casting machine of the present invention in which a cast piece having a relatively large plate thickness is cast from the state of FIG. 1 without moving the side dam in the casting direction.

FIG. 5 is a front view showing a state where the side weir is moved in the casting direction from the state of FIG. 1 to cast a slab having a relatively large plate thickness in the continuous metal strip casting machine of the present invention.

FIG. 6 is a view showing another structure of the metal ribbon continuous casting machine of the present invention.

FIG. 7 is a view showing a known twin-drum type metal ribbon continuous casting machine.

FIG. 8 is a view showing a known twin-belt type metal ribbon continuous casting machine. Is.

[Explanation of symbols]

1,1 'Endless belt 2,2' Upper guide roll 3,3 'Lower guide roll 4,4' Side weir 5 Belt running direction 6 Molten metal 7 Melt pool 8 (8 ') Solidified shell 9 (9') Tension roll 10 Metal ribbon 11, 11 'Guide roll 12, 12' Cooling device 13 Old position of endless belt 14 Old position of upper roll 15 Old position of lower roll 16 Old position of tension roll 17 Old position of cooling device 18 (18a, 18b) ) Rotating drum, 19 (19a, 19b, 19c, 19a ', 19b',
19c ') Pulley

Claims (1)

[Claims] 1. An endless belt (1), (1 ') which is stretched and runs to form a long side surface of an upper wide mold, and is sandwiched between the endless belts (1) and (1'). It is characterized by having wide side dams (4), (4 ') forming the short sides of the mold, and the plate surface shape of the wide mold and the side surface shape of the corresponding side dam are arc-shaped. A continuous casting machine for metal ribbon.