JPH0511006Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an apparatus for manufacturing a solidified thin plate having a target thickness with little thickness deviation in a continuous thin plate casting machine.

[Prior Art] Conventionally, in order to manufacture thin metal plates, such as thin steel plates, a steel ingot is bloomed to obtain a slab with a thickness of 200 to 250 mm, and this slab is hot-rolled in a hot strip mill. , or by continuous casting of molten steel to obtain a slab, which is then hot rolled.

However, when using these conventional techniques,
It is desired to develop a technique for directly obtaining thin plates by continuous casting of molten steel from large-scale hot strip mills and places that require energy to heat slabs.

Conventionally, when continuously casting molten steel, a method has generally been used in which the molten steel is injected into a mold, solidified around the cross section, and then pulled out downward. However, with this method, it is difficult to obtain slabs with a thickness of several tens of millimeters or less due to the relationship between the diameter of the nozzle through which molten steel is injected into the mold and the cross-sectional dimensions of the mold.

Due to the friction between the slab and the inner wall of the mold, it is difficult to increase the slab withdrawal speed above 2 m/min, and if it exceeds 2 m/min, there is a danger that the solidified shell will break and a flow of molten steel will blow out (breakout). There is.

I had a problem.

In order to solve these problems in the conventional continuous casting process and provide an efficient manufacturing method and apparatus for continuous casting of thin sheets, the applicant previously published Japanese Patent Application No. 56-188862 to manufacture thin metal sheets by single-sided casting. A manufacturing method and device were proposed.

That is, this method and apparatus is a method of pouring molten steel onto a flat plate forming an inclined endless track to cast a thin steel plate, and in which the casting direction and the method of pouring molten steel flow are reversed.
In other words, the molten steel is poured onto the flat plate while the flat plate forming the endless track moves upward on the slope, and the lower end of the molten steel (molten metal) flow on the inclined moving flat plate is self-retained by the surface tension of the molten steel. a belt mechanism driven by a drive wheel that forms an endless track and has an inclined plane; a means for supplying molten metal downward onto the inclined belt plane; and a method for extracting slabs above the inclined plane. This is a continuous casting device for molten metal, which consists of a device that drives a belt upwardly on a slope via a drive wheel.

With this technique, steel plates with a thickness of 2 to 20 mm, for example, can be manufactured by continuous casting. According to this technology, molten steel (molten metal) solidifies on a track plane that is inclined and moves upward, and the extraction speed of the solidified shell (slab) and the moving speed of the track plane (belt) are synchronized. If so, breakout due to friction between the belt surface and the slab will not occur, so the casting speed can be dramatically increased.

In addition, since it is one-sided solidification, the bottom surface of the slab is in contact with the belt surface during casting, but the top surface is in contact with the molten steel or the atmosphere, and since there is no space constraint such as a mold, the molten steel is transferred from the tundish to the tundish. There are no problems with the nozzle arrangement for supplying the water.

The present applicant has further improved this technique and provided a fixed weir extending in the width direction of the metal belt at the lower end of the molten metal injection flow so as to be in elastic contact with the metal belt. In Japanese Patent Application No. 59-120588, we proposed a process to solve the problem of wrinkling of slabs caused by the uneven planar shape of the tip of the molten metal injection flow on the metal belt by forming a pool of molten metal on the metal belt. did.

[Problems to be solved by the invention] Furthermore, with this method, in the molten metal pool,
This is caused by the progress of solidification in the area in contact with the side weir.
The formation of so-called "ears" in slabs can be effectively suppressed by lining the side weir with a fireproof heat insulating material as proposed in Japanese Patent Application No. 178584/1984. In addition, solidification of molten metal occurs at the fixed weir extending in the width direction of the metal belt at the rear end of the sump, resulting in uneven slab thickness and the occurrence of cracks called cold shatter. 1986
This can be greatly improved by equipping the fixed weir itself with heating means, as proposed in No. 178585.

However, even with these conventional techniques, the non-uniform solidification progress of the molten metal has not been completely achieved, and the problem of non-uniform slab thickness still remains. The object of the present invention is to provide a molten metal injection flow control device that uniformly solidifies the molten metal and produces a solidified thin plate with no thickness deviation and a target thickness.

[Means and effects for solving the problems] The present invention consists of a metal belt 1 that runs while ascending diagonally as shown in FIG. and a side weir 4 running on the metal belt 1 in the width direction.
Molten metal 8 is injected into a space formed by a rear weir 5 extending and fixed between the two, and the molten metal is cooled and solidified by a cooling device 3 via a belt 1, and is taken out as a solidified thin plate 9. In the machine, a plurality of stoppers 14, 14 shown in FIG.
-1,..., 14-n, and lower tanks 6, 6-, which are divided in the belt width direction corresponding to the stoppers 14, 14-1,..., 14-n, respectively. 1,...,6-n and the 6-1,...,
A tundish 18 consisting of an injection nozzle provided at 6-n, and a liquid level meter 17 for detecting the level of the molten metal 8 on the metal belt 1 shown in FIG.
Based on the information detected by the liquid level meter 17, the molten metal 8 on the metal belt 1 is further adjusted so that the thickness of the solidified thin plate 9 in the width direction is the same and reaches the target thickness. Molten metal injection flow control in a thin plate continuous casting machine, comprising a stopper drive device 15 that independently controls and opens and closes the stoppers 14, 14-1..., 14-n so that the liquid level does not fluctuate. It is a device.

In the present invention, the liquid level meter 17 detects the height of the hot water level and operates the stopper driving device 15. In order to keep the thickness of the solidified thin plate constant, it is important to control the molten metal level so that it does not fluctuate.

The tundish 18 of the present invention has lower tanks 6-1, . . . , 6-n that are divided in the width direction. The stoppers 14, 14-1, .
The amount of molten metal injected from the injection nozzles provided at 1,..., 6-n can be controlled more precisely than before, reducing deviations in the thickness of the solidified thin plate and achieving the target thickness. . In Fig. 1, 16 is the plate thickness gauge, which is located immediately after leaving the metal belt 1.
Although this is an example in which the thickness of the solidified thin plate 9 is measured at a plurality of points in the width direction, if this plate thickness gauge 16 is incorporated into the apparatus of the present invention, more favorable results can be obtained in terms of molten metal injection control.

Although the stopper 14 in FIGS. 1 and 2 is an example using a stopper rod, the stopper 14 may be a known sliding nozzle type stopper with the same effect. Therefore, the stopper of the present invention also includes a sliding nozzle type stopper.

[Effects of the invention] According to the invention, a solidified thin plate with a small thickness deviation and a target thickness can be manufactured using a continuous thin plate casting machine.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example in which the device of the present invention is combined with a thin plate continuous casting machine, and FIG. 2 is a diagram showing an example of the tundish of the present invention. 1...Metal belt, 2...Pulley, 3...Cooling device, 4...Side weir, 5...Rear weir, 6,6-
1,...,6-n...lower tank, 7...injection flow, 8...
... Molten metal, 9 ... Solidified thin plate, 10 ... Roll roll,
11... Winding device, 12... Thin plate coil, 13
... Upper tank, 14, 14-1, ..., 14-n ...
Stopper, 15...stopper drive device, 1
6...Plate thickness gauge, 17...Liquid level gauge, 18...
Yesterday.

Claims (1)

[Scope of utility model registration request] A metal belt 1 that runs while ascending diagonally; a side weir 4 that is disposed on both sides of the metal belt 1 and runs at a speed synchronized with the metal belt 1; The molten metal 8 is placed in the space formed by the rear weir 5 extending and fixed between the
In a molten metal injection flow control device for a thin plate continuous casting machine, in which the molten metal is injected and cooled and solidified by a cooling device 3 via a belt 1 and taken out as a solidified thin plate 9, a plurality of stoppers 14-1, ..., 1 are used.
4-n and the stopper 14
Lower tanks 6-1, ..., which are provided separately in the belt width direction corresponding to -1, ..., 14-n, respectively.
6-n and injection nozzles provided on the 6-1, . . . , 6-n; Based on the information detected by the level meter 17, the liquid level of the molten metal 8 on the metal belt 1 is adjusted so that the thickness of the solidified thin plate 9 in the width direction is the same and reaches the target thickness. A molten metal injection flow control device for a thin plate continuous casting machine, comprising a stopper driving device 15 that independently controls the stoppers 14-1, . . . , 14-n to open and close the stoppers 14-1, .