JP3454179B2 - Continuous casting mold - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mold for continuous casting of molten metal such as molten steel. Immediately after starting the drawing of the solidified shell, the solidified shell causes bulging under the mold, and its overhanging portion is caught by a roll chock of a support roll. Thus, the present invention relates to a continuous casting mold that prevents the solidified shell from coming off the dummy bar.

[0002]

2. Description of the Related Art Generally, in continuous casting of molten metal such as molten steel, a dummy bar is inserted into the mold from above or below the mold to start casting, and then molten metal such as molten steel is supplied into the mold from above the mold. . A dummy bar head is mounted on the uppermost end of the dummy bar, and a cooling material for accelerating the cooling of the molten metal is arranged on the dummy bar head.

After the molten metal such as molten steel supplied into the mold is cooled to form a solidified shell having sufficient strength to withstand drawing, while the molten metal such as molten steel is supplied from above the mold, the dummy bar Pull out the coagulation shell by induction.

[0004]

In the conventional continuous casting mold as shown in FIG. 5, a molten metal such as molten steel is supplied into the mold at the start of casting, and then it can withstand drawing in a short time. In order to form a strong solidified shell, a sufficient amount of cold material (not shown) must be properly placed over the dummy bar head. Therefore, it took a long time to prepare for casting.

If the arrangement of the cold material is simplified in order to shorten the time required for the preparation for casting, a solidified shell having sufficient strength is not formed, so that when the dummy bar is pulled out by induction, the solidified shell is formed below the mold. Cause bulging. The overhanging portion caused by bulging is caught in the roll chock of the support roll, which causes unstable operation and equipment failure. When the overhanging part due to bulging is caught in the roll chock, not only problems related to such equipment, but also the position of the molten metal level in the mold fluctuate and the quality of the solidified shell deteriorates. The quality of the slab after being cooled to a low temperature also deteriorates.

[0006] The present invention provides a continuous casting mold capable of stabilizing the operation and improving the quality of the solidified shell by preventing the overhang portion caused by the bulging of the solidified shell from being caught by the roll chock of the support roll. With the goal.

[0007]

Means for Solving the Problems The present invention relates to a method of melting molten steel or the like which constitutes a casting space whose upper and lower sides are opened by a pair of opposed mold long sides and a pair of opposed mold short sides between the long sides. In a metal continuous casting mold, a mold that holds the protruding portion of the solidified shell at a position below the long side of the mold and at a position that does not prevent the solidified shell from being pulled out, thereby preventing catching.
It is a continuous casting mold in which a guide separated from the above is provided.

The present invention also provides a pair of opposed mold long sides.
And a pair of opposing mold short sides between their long sides.
Therefore, the molten steel, etc. that composes the casting space that is open at the top and bottom
In the mold for continuous casting of molten metal,
The solidified shell to a position that does not prevent the solidified shell from being pulled out.
A guide is installed to prevent catching by pressing the protruding part
As well as, the position of the distal end surface facing the guide solidified shell, mold for continuous casting that is provided between the distal end surface facing the casting side of the mold long sides, of the support rolls to the solidified shell of the roll chocks Is. Further, in the continuous casting mold, the guide is disposed so that the tip position of the guide can be adjusted between the casting side surface of the long side of the mold and the tip surface of the roll chock. Here, the casting side surface of the long side of the mold is a surface where the long side of the mold contacts the molten metal in the mold.

In the present invention, the guide is arranged between the lower side of the long side of the mold and the upper side of the roll chock of the uppermost support roll, or a plurality of guides are arranged in the width direction of the long side of the mold for continuous casting. It is a mold.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below with reference to the drawings. FIG. 5 schematically shows the situation immediately after the start of the drawing of the solidified shell in the conventional continuous casting mold.
The long side of the mold is formed by integrally forming the copper plate 1 and the back frame 2 which are in contact with the molten metal in the mold. A support roller 7 of a solidified shell is arranged below the long side of the mold, and the support roller 7 is supported by a roll chock 6.

A dummy bar head 8 is mounted on the uppermost end of the dummy bar (not shown), and a cooling material (not shown) for promoting cooling is arranged on the dummy bar head 8. Molten metal such as molten steel supplied into the mold from above the mold at the start of casting is cooled in the mold. In this way, the molten metal in the mold is solidified at its periphery to form a solidified shell 9 whose interior is not solidified. When the solidified portion around the solidified shell 9 develops and has sufficient strength, the solidified shell 9 is guided by the dummy bar head 8 mounted on the uppermost end of the dummy bar (not shown) and pulled out below the mold. .

When the preparation time for starting the casting is short and the amount of the cold material is small, the solidified portion around the solidified shell 9 just above the dummy bar head 8 is not sufficiently developed, and the inside of the solidified shell 9 is not sufficiently developed. The static pressure of the molten metal causes blistering on the outside of the solidified shell 9. This is called bulging. If the overhanging portion 10 caused by bulging is large, the overhanging portion 10 is the corner portion 11 of the roll chock 6.
As a result, the dummy bar head 8 and the solidification shell 9 are disengaged from each other and normal drawing cannot be performed, and the level of the molten metal in the mold fluctuates and the quality of the solidification shell 9 deteriorates. .

On the other hand, in the present invention, as shown in FIG. 1, the guide 3 is arranged between the long side of the mold and the roll chock 6.
The position of the tip end surface of the guide 3 facing the solidification shell is set between the casting side surface of the copper plate 1 of the mold and the tip end surface of the roll chock 6 on the solidification shell 9 side. When the tip surface of the guide 3 is set to this position, the guide 3 holds down the overhanging portion 10 caused by the bulging of the solidified shell 9,
It is possible to prevent the protruding portion 10 from being caught by the corner portion 11 of the roll chock 6. Further, as shown in FIG. 2, the guide 3 can be arranged between the roll chock 6 and the roll chock 6 immediately below it. Further, the guide 3 can be arranged at both positions illustrated in FIGS. 1 and 2.

When the mold copper plate 1 is used for a long period of time, it is worn by the solidified shell 9 and the surface on the casting side recedes toward the back frame 2. Since the guide 3 is provided with a device for adjusting the position, as the surface of the mold copper plate 1 on the casting side is retracted, the position of the tip end surface of the guide 3 is also retracted so that the guide 3 can always be adjusted to an appropriate position. The configuration of the adjusting device for the position of the guide 3 is not limited to a specific form, but it is desirable to use a cylinder, bolts, or the like to enable fine adjustment.

FIG. 1 shows an example of a continuous casting mold according to the present invention.
And shown in FIG. In FIG. 1, the guide 3 is arranged between the lower side surface of the long side of the mold and the upper side surface of the roll chock 6 of the uppermost support roll 7. In FIG. 2, the guide 3 is arranged between the roll chocks 6. In either case,
The position of the tip surface of the guide 3 is set between the casting surface of the copper plate 1 which is the long surface of the mold and the tip surface of the roll chock 6 on the solidification shell 9 side. When the guide 3 is set to this position, the guide 3 presses the projecting portion 10 generated by the bulging of the solidified shell 9, and the projecting portion 10 can be prevented from being caught by the corner 11 of the roll chock 6. In the case where the preparation time for starting casting is short and a sufficient amount of cold material (not shown) cannot be arranged, stable operation can be performed even if the solidified portion around the solidified shell 9 is not sufficiently developed.

When the mold copper plate 1 is used for a long period of time, it is worn by the solidified shell 9 and the surface on the casting side recedes toward the back frame 2. Since the guide 3 is provided with a device for adjusting the position, as the surface of the mold copper plate 1 on the casting side is retracted, the position of the tip end surface of the guide 3 is also retracted so that the guide 3 can always be adjusted to an appropriate position. 1 and 2 show an example of a configuration in which the position of the tip end surface of the guide 3 is adjusted by the bolt 4. In particular, in the embodiment of FIG. 2, if the tip end surface of the guide 3 is shaped as shown in FIG. 3, more stable operation is possible.
The adjustment of the position of the tip surface of the guide 3 is appropriately determined by measuring the amount of wear of the mold copper plate 1, measuring the number of charges, and the like.

Further, the guide 3 does not need to be arranged without a gap over the entire width of the long side of the mold, and the object can be achieved by appropriately disposing the guide 3 in the width direction as shown in FIG.

[0018]

The mold shown in FIG. 1 is repeatedly used for 1000 charges or more, but the problem that the solidified shell 9 is caught by the roll chock 6 does not occur. As described above, according to the present invention, it is possible to stabilize the operation and at the same time suppress the fluctuation of the molten metal level in the mold to improve the quality of the cast slab.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a continuous casting mold of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the continuous casting mold of the present invention.

FIG. 3 is a sectional view showing another embodiment of the continuous casting mold of the present invention.

FIG. 4 is a side view showing an embodiment of the continuous casting mold of the present invention.

FIG. 5 is a sectional view showing a conventional continuous casting mold.

[Explanation of symbols]

1 Copper plate on the long side of the mold 2 back frame 3 guides 4 volt 5 Thrust block 6 roll chock 7 Support Roll 8 dummy bar head 9 solidification shell 10 Overhang part 11 Roll chock corner

─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-49-65329 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B22D 11/04 311

Claims (5)

(57) [Claims] 1. A continuous casting mold of molten metal, which comprises a pair of opposed mold long sides and a pair of opposed mold short sides between the pair of long sides, which forms a casting space opened up and down. A continuous casting mold characterized in that a guide separate from the mold for preventing the solidification shell from projecting is disposed below the long side of the mold and at a position where it does not hinder the extraction of the solidification shell. 2. A pair of mold long sides facing each other, and the pair of lengths.
Up and down by a pair of short mold sides that are between the sides and are opposed
Continuous casting of molten metal forming a casting space with open
In the mold, below the long side of the mold and pulling the solidification shell
Prevents the solidified shell from overhanging at a position that does not prevent extraction
The guide is disposed, and the position of the tip end surface of the guide facing the solidification shell is between the casting side surface of the long side of the mold and the tip end surface of the roll chock of the support roll facing the solidification shell. It is characterized by being arranged as
That continuous casting mold. 3. The position of the tip end surface of the guide facing the solidification shell is arranged so as to be adjustable.
The continuous casting mold according to 1 or 2. 4. The continuous casting mold according to claim 3, wherein the guide is arranged between the lower side of the long side of the mold and the upper side of the roll chock of the uppermost support roll. 5. The continuous casting mold according to claim 4, wherein a plurality of guides are arranged in the width direction of the long side of the mold.