JPH09277003A - Method for preventing stockiness of cutting slag and burr to cut cast slab in continuous casting and executing device thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely prevent the stickiness of slag and burr developed at the time of gas-cutting a cast slab to the cast slab from occurring in continuous casting. SOLUTION: A cast slab cutting device body 8 has a cast slab clamping device 3 and a cutting gas torch 2 synchronously descended with the cast slab 1 in a cast slab drawing process of the continuous casting. In this case, a cylinder 4 is set below the cutting gas torch setting position of the case slab cutting device body 8 and two supporting arms 6 hinged so as to be vertically turnably adjusted and extended to the rear side of the cast slab 1 at symmetrical position with the cast slab cutting device body 8 passing through the outside of both side surfaces of the cast slab 1 are provided at the tip part of the cylinder arm 5 of a cylinder 4. A water cooling slag shut-off plate 7 is fitted to the tip parts of two supporting arms 6 by dridging so that the upper surface of the water cooling slag shut-off plate 7 matches the upper surface of the cut surface of the cut cast slab 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is an apparatus for preventing burrs from adhering to a slab on the opposite side of a cutting gas torch when horizontally cutting a slab produced by continuous casting. It is about.

[0002]

2. Description of the Related Art Generally, when a cast slab is gas-cut when casting a slab by a continuous casting apparatus, a cutting gas torch is formed on the surface of the slab opposite to the cutting gas torch below the cutting surface. Solidify and burr is generated and adheres,
It is necessary to remove this burrs because it causes quality deterioration in the rolling process which is a post process.

In order to remove this burrs, conventionally, there is a method in which after the adhered slag has solidified, an external force such as hammering is applied in the process downstream from the slab cutting site to remove it. Is disclosed in. or,
For example, Japanese Patent Laid-Open No. 57-199554 discloses a method of preventing adhesion by cutting a cast piece and the iron plate together after the iron plate is pressed or pressure-bonded to the gas cutting surface. Furthermore, a method of blowing air to the molten slag and causing it to scatter is disclosed in, for example, Japanese Patent Application Laid-Open No. 3-281046. Furthermore, Japanese Patent Laid-Open No. 6-170510 discloses a method of synchronizing a cutting gas torch with a special refractory brick and blowing out the molten slag with a jet gas of the torch.

[0004] The conventional techniques for removing such burr can be roughly classified into the following three types. (A) A method of removing the adhered glue after it is solidified. (B) A method in which an iron plate is applied to the gas cut surface of the slab and cut together so that no debris adheres. (C) In order to prevent adherence of slag simultaneously with gas cutting, it is a method of blowing air to scatter the slag, or a method of using a special refractory to blow off with a jet gas of a cutting gas torch.

The method (a) cannot completely remove all kinds of steels, and sometimes hinders the process. Further, once attached, the heat loss of the cast piece at that portion is blocked, so the heat history of the cast piece differs from that of the other portions, and as a result, quality deterioration during the subsequent heating or rolling cannot be prevented.

The method (b) is a method in which no burrs are attached at the time of cutting, but since the anti-adhesion iron plate or the anti-adhesion pressure contact plate is cut together with the cast piece, continuous casting is performed. It is necessary to constantly supply a new anti-sticking iron plate or anti-sticking pressure contact plate to the piece. But,
This was physically impossible, or even if possible, it was extremely expensive and extremely difficult to put into practical use.

The method (c) is a method in which burrs are treated at the time of cutting a cast piece, but the degree of scattering in molten slag of all steel types is not the same, and therefore, the scattering may not be completed. In addition, there is a case where the slab is scattered and adheres to a place other than the cut surface of the slab, and eventually becomes adhesion burrs. Alternatively, since the slag that is scattered and adheres to the peripheral equipment including the scattering prevention cover and the like is accumulated, it is often necessary to stop and remove the casting.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the conventional technology for removing burrs, in which burrs generated during gas cutting of a slab adhere to the slab. The present invention intends to provide a method and an apparatus for implementing the same that reliably prevent the above.

[0009]

In order to achieve the above object, the means of the present invention is, in the invention of claim 1, a method of cutting a slab in a drawing step of continuous casting by a cutting gas torch at a vertical portion thereof. Cutting from the position symmetrical with the cutting gas torch with the slab sandwiched, cut the water-cooled cutting slag shield plate in close contact with the cutting gas torch cutting timing on the rear surface of the slab immediately below the cutting surface where burrs are generated. Is a method for preventing adhesion of cutting burrs to cutting slabs in continuous casting, which is characterized by preventing adhesion of cutting burrs to cutting slabs.

According to the second aspect of the present invention, in the slab cutting apparatus main body 8 provided with the slab clamping device 3 and the cutting gas torch 2 which descend in synchronism with the slab 1 in the slab drawing process of continuous casting, the slab cutting apparatus body 8 is cut. The cylinder 4 is installed below the cutting gas torch installation position of the apparatus main body 8, and is vertically supported on the tip end of the cylinder arm 5 of the cylinder 4 so as to be vertically pivotable, and is cast through the outside of both side surfaces of the cast slab 1. Two support arms 6 extending to the rear side of the slab 1 symmetrical to the one-side cutting device body 8 are provided, and the upper surfaces of the water-cooled slag shielding plate 7 and the cut surface 13 of the slab 12 are provided at the tips of the two support arms 6. Is a device for preventing adhesion of cutting burrs to cutting slabs in continuous casting, characterized in that a water-cooled slag shielding plate 7 is attached so as to be able to coincide with the upper surface of the slab.

The operation of the present invention will be described. In the slab drawing process of continuous casting, the support arm 6 for supporting the water-cooled slag shield plate 7 is synchronized with the slab 1 and the cutting gas torch 2 when cutting the slab and the supporting arm 6 of the cylinder 4 is supported. Hold and lower the cylinder arm 5. At the place where the molten slag is flowing out from the cut surface 13 of the cut slab 12 cut at this time, the cylinder 4 is operated to contract the cylinder arm 5 to cast the water-cooled slag shield plate 7 from the other side of the slab 1. Put it on the rear side of piece 1 in close contact. A part of the slag that has flowed out passes through the water-cooling shield plate 7 and is discharged as a drop slag 10, while the remaining slag is not scattered on the water-cooling shield plate 7 and is outside the cut surface 13 of the cutting slab 12. It is floated and once solidified on the water-cooling shield plate 7 to form a solidified glue 11. After the cutting gas torch 2 and the water-cooled slag shield plate 7 have finished synchronizing with the slab 1 after the cutting of the cast slab, the support arm 6 of the water-cooled slag shield plate 7 is caused to actuate the cylinder 4 at the tip of the solidification burrs 11. The solidified burrs 11 are peeled off from the joints of the cutting slabs 12 by being hooked by the water-cooled shield plate 7 and slid on the water-cooled shield plate 7 to be dropped and discharged. Since the fallen burrs fall in the same place, they can be collected by, for example, a scale sluice or the like, and the collection process is easy.

According to this method, the molten slag is prevented from adhering to the slab by the water-cooled slag shielding plate during gas cutting of the slab. Therefore, no burrs hang down or scatter and adhere to the surface of the cut surface of the cut slab. Noroburari solidified on the water-cooled Noro shielding plate is only slightly connected to the edge of the slab cut surface. That is, since the entire solidified burrs have already floated from the surface of the slab and are only attached to the slab only at the tip, as shown in FIG. Can be easily peeled off from the root and dropped.

In this case, the shielding plate does not necessarily need to be water-cooled, but water-cooling is very effective in consideration of compatibility with all steel types and maintenance of equipment. That is, at the final stage of this adhesion prevention, the solidification on the shielding plate is physically removed, but at this time, if the joint between the solidification and the cut slab is not sufficiently cooled and becomes brittle, it may not be complete depending on the steel type. It may not come off. However, since this joint is very weak, it immediately drops 100% on the slab conveying line thereafter. However, since the place where it falls is not constant, it takes extra time and labor to clean up after falling. Further, considering that the surface temperature of the slab at the time of cutting is as high as 800 ° C. or higher, it is preferable to perform water cooling from the viewpoint of facility maintenance.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a side view of a device for preventing adhesion of cast slab cutting burrs showing an embodiment of the present invention, and FIG. 2 is a plan sectional view thereof. Further, FIG. 3 shows the state of adhesion of the cut slab and the burr at the time when the cutting according to the present invention is completed. In these drawings, 1 is a slab, 2 is a cutting gas torch, 3 is a slab clamp device, 4 is a water-cooled slag shield plate 7
Cylinder for activating the cylinder, 5 is a cylinder arm, 6 is a support arm, 7 is a water-cooled slag shield plate, 8 is a slab cutting device main body, 9 is a slag shield plate retracted position, and 10 is a water-cooled shield plate and drops. Noro, 11 is a solidified Noro burr solidified on the water-cooled shield, 12 is a cast piece, 13 is a cut surface, 14 is a casting drawing direction, and 15 is a torch turning direction.

As shown in the figure, in the slab drawing process of the vertical continuous casting apparatus, the slab cutting apparatus main body which holds the slab 1 being drawn by the slab clamp device 3 and descends in synchronization with the slab 1. 8 are provided. The slab cutting device body 8 is further provided with a cutting gas torch 2 for cutting the slab 1 that is descending.

In the slab cutting device body 8 described above, the cylinder 4 is further provided in the slab cutting device body 8. The mounting position of the cylinder 4 on the slab cutting device body 8 is slightly below the installation position of the cutting gas torch 2. Cylinder 4
At the tip of the cylinder arm 5, two support arms 6, 6 bifurcating are pivotally supported so as to be vertically adjustable.
The two supporting arms 6, 6 branched into two branches pass through the outer sides of the slab 1 and are symmetrical with the slab cutting device body 8.
Extending to the rear side of. These two support arms 6,
A water-cooled slag shield plate 7 is bridged at the tip of 6. When the cylinder 4 is actuated and the support arms 6 and 6 are contracted by the cylinder arm 5 to draw the water-cooled slag shield plate 7 toward the slab 1 and abut it, the upper surface of the water-cooled slag shield plate 7 and the cut slab 1
The support arm is pivotally supported so that the upper surface of the second cut surface 13 is aligned. With the above configuration, the water-cooled slag shield plate 7 is lowered by the cast piece cutting device body 8 in synchronization with the cast piece 1 to be cut.

The method of the present invention will be described with reference to the drawings.
It is necessary to cut the slab 1 while descending in synchronization with the downward movement of the slab 1 during the drawing process of continuous casting. Therefore,
As a cutting start preparation step for cutting, the slab clamp device 3 of the slab cutting device main body 8 is operated in order to synchronize with the downward movement of the slab 1, and the slab 1 is gripped and moved downward. Then, the cutting gas torch 2 descends in perfect synchronization with the movement of the slab 1 as the slab cutting device body 8 moves downward. Then, in the conventional device, the cutting gas torch is ignited,
Although the cutting is started, in the method of the present invention, the operation of the slab clamp device 3 causes the slab to descend in synchronism with the slab 1, and the cylinder 4 operates to contract the cylinder arm 5 and, as shown in FIG. Then, the water-cooled slag shield plate 7 is moved from its retracted position 9 to a position where it comes into contact with the rear surface of the slab 1.

Then, as in the conventional cutting method, the cutting gas torch 2 is ignited. Cutting is started, and the cutting gas torch 2 is swung in the torch swivel direction as shown in FIG. On the rear surface side of the cast slab, the molten slag flows out from the cut surface 13 along with the cutting. However, as shown in FIG. 1, this molten slag passes through the water-cooled slag shield plate and flows down to become a dropping slag 10, or is rapidly cooled on the water-cooled slag shield plate 7 and solidifies to become a solidification paste.

When the cutting is completed, the solidified burrs 11
As shown in FIG. 3, is connected to the cutting slab 12 only at its tip, and is in a state where it can be peeled off by applying a slight external force. Then, the clamp of the slab clamp device 3 is opened to release the synchronization between the slab 1 and the water-cooled slag shield plate 7. Simultaneously with this opening, the cylinder 4 operates, and
As shown in FIG. Then, the burrs 11 are peeled off from the root by an external force caused by both the lowering of the cast slab 1 and the backward movement by the cylinder 4, and slide on the water-cooled slag shielding plate to fall.

[0020]

INDUSTRIAL APPLICABILITY According to the present invention, burrs are formed so that they can be easily peeled off without scattering at the portion where burrs are generated on the cast slab, and by peeling the burrs, 100% of the burrs themselves are attached. % With the method for preventing adhesion of cast slag and the apparatus for implementing the same, the following excellent effects can be achieved. (1) It is possible to prevent quality deterioration in heating or rolling in the subsequent process at almost no running cost, and there is a great advantage in both quality and cost. (2) The surface scratches contained when mechanically peeling off the already attached burrs do not occur at all.

That is, in general, when a continuous cast slab material of steel is rolled through a heating furnace, the slab surface layer is once cooled to below the Ar ₃ point and transformed into γ → α + Fe ₃ C to obtain a slab surface. A slab cooling technique has been carried out by strengthening the layer to prevent quality deterioration due to the surface during rolling or the like. At that time, if cutting burrs due to the cutting gas torch are attached to part of the slab, it will not be cooled as specified by this cooling, or the heat loss during this cooling after cutting will be the part without cutting burrs. Since it is smaller than that of No. 1, there is a difference in the slab structure, resulting in unevenness. Therefore, in the rolling in the subsequent process, quality deterioration occurred in the rolled steel material in the vicinity of the part where the burrs were adhered to the slab, or the boundary between the part where the burrs were adhered and the part where it was not adhered. However, according to the present invention, these quality deteriorations can be prevented with almost no running cost.

[Brief description of drawings]

FIG. 1 is a side view of a cast piece cutting locomotive adhesion preventing device showing an embodiment of the present invention.

FIG. 2 is a plan view of a cast piece cutting locomotive adhesion preventing device showing an embodiment of the present invention.

FIG. 3 is a schematic diagram for explaining a state of adhesion of a slab and a burr immediately after cutting is completed.

[Explanation of symbols]

 1 Cast Piece 2 Cutting Gas Torch 3 Cast Piece Clamping Device 4 Cylinder 5 Cylinder Arm 6 Support Arm 7 Water-cooled Noro Shielding Plate 8 Cast Piece Cutting Device Main 9 Noro Shielding Plate Retracting Position 10 Dropping Noro 11 Solidified Norobur 12 Cutting Cast Piece 13 Cutting Surface 14 Slab withdrawal direction 15 Torch rotation direction

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[Procedure amendment]

[Submission date] April 17, 1996

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Figure 2

[Correction method] Change

[Correction contents]

[Fig. 2]

Claims (2)

[Claims] 1. A method of cutting a slab in a drawing step of continuous casting with a cutting gas torch at a vertical portion thereof,
Cutting from a position symmetrical with the cutting gas torch with the slab sandwiched.By cutting the water-cooled cutting slag shield plate on the rear surface of the slab just below the cutting surface where burrs are generated in close contact with the cutting timing of the cutting gas torch. A method for preventing adhesion of cutting burrs to a cutting slab in continuous casting, which prevents adhesion of cutting burrs to a cutting slab. 2. A slab cutting device main body 8 comprising a slab clamping device 3 and a cutting gas torch 2 that descend in synchronism with a slab 1 in a slab drawing process of continuous casting, in which the slab cutting device main body 8 is cut. The cylinder 4 is installed below the gas torch installation position, and the tip of the cylinder arm 5 of the cylinder 4 is pivotally supported up and down so that the cylinder 4 can be pivoted up and down. Slab 1 symmetrical to
Are provided with two support arms 6 extending to the rear side, and the upper ends of the water-cooled slag shield plate 7 and the cut surface 13 of the cut slab 12 are bridged at the tips of the two support arms 6 so that they can be aligned with each other. A device for preventing adhesion of cutting burrs to cutting slabs in continuous casting, characterized in that a slag shielding plate 7 is attached.