JPH0615421A - Casting method of continuous casting machine and circulating casting device - Google Patents

Abstract

PURPOSE:To shorten filling time of molten metal by concentrically arranging a ladle, tundish and plasma torch and starting pouring and heating of the molten metal into the tundish from the front of the casting position while synchronously rotating. CONSTITUTION:The ladle 4, tundish 7 and plasma torch 16 are concentrically arranged around the rotating axis 2. The ladle 4 containing the molten steel is held at the position A starting prefilling, and the molten steel is poured into the downward tundish 7. Simultaneously with this operation, the heating of the molten steel is executed by the plasma torch 16. These are shifted to the casting position B at the same speed and the casting from the tundish 7 into a mold is executed. When the ladle 4 becomes empty during casting, this ladle is shifted to the retreating position C and replaced with a new ladle 4 filled with molten steel. As the start of the casting can immediately be executed after the new ladle reaches the casting position B, trouble of the clogging of a sliding nozzle caused by the prefilling, etc., is not developed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for casting molten steel into a mold in a continuous casting machine and a casting apparatus useful for carrying out the method, and more particularly to a tundish unidirectionally along a circular rail. The present invention relates to a pouring method and a circulating pouring device for a continuous casting machine of a type in which pouring is started in a tundish before turning to a pouring position and pouring is performed while turning.

[0002]

2. Description of the Related Art Generally, in casting a molten steel into a mold in a continuous casting machine, the molten steel from a ladle is once received by a tundish, and the molten steel flow is controlled from the tundish to pour the molten steel into the mold. There is. Traditionally, in order to facilitate the movement of the tundish to the pouring position and the retreat of the tundish after pouring, the tundish is circularly moved in one direction across the circular rail across the pouring position. A tundish rotary type continuous casting machine is known (for example, Japanese Patent Publication No. 52-3304).
9 gazette, Japanese Patent Publication No. 53-40566, etc.). In these, the tundish is cantilevered on a tundish car and the tundish car is swiveled on a circular rail to enclose the center of rotation of the ladle turret or the ladle turret is swung. The structure is such that the tundish car is swung along the rail with the axis as a guide. In addition, it is already practical application 2-83
The tundish circulation device proposed in the 967 specification installs a circular rail having a center on a pouring yard on the side opposite to the turning center of the ladle turret with respect to the pouring position, and casting is performed in the vicinity of the circular rail. A slag device and a preheating device that operate with respect to the end-of-loading tundish are arranged, and the tundish car is placed along the circular rail at the pouring position, the slag position,
It is also designed to circulate between preheating positions.

Among the above-mentioned conventional devices, Japanese Examined Patent Publication No. 52-33
No. 049, and Japanese Patent Application No. 2-83967
All of the proposals in the specification have a structure in which molten steel is injected from a ladle when the tundish reaches the pouring position. However, in Japanese Patent Publication No. 53-40560, the pouring preparation time is further shortened. Therefore, it is also suggested to complete the pouring of the tundish in a fixed position when the tundish is in the pouring preparation position and move the tundish to the pouring position in this state.

[0004]

The structure in which the tundish car is circularly moved around the circular rail has been known in the prior art in which the tundish car moves linearly back and forth alternately between the standby positions on both sides of the pouring position. Compared to the tundish reciprocating device, it is a one-way movement, so the operation is smooth and the drive part is simplified.Although it has the advantage that it can be run without interference between tundish, The circular movement of the dish car does not significantly reduce the preparation time between pouring operations. In particular, the above-mentioned Japanese Patent Publication Sho 5
In the publications of JP-A 2-33049 and JP-B-53-40566, since the work such as the removal of the tundish after the pouring is done in another dedicated maintenance place, the work or the transfer work therefor. A lot of time and labor is required for the repair work for removing the solidification of the residue. In this respect, the above-mentioned actual application 2-839
The apparatus proposed in No. 67 is designed so that the tundish is pulled out to the slag device on the casting floor adjacent to the circular rail to perform the slag work, and preheating is performed on the circular rail. Although this brings a great advantage in shortening the time and improving the efficiency of production, in this device, the pouring time to the tundish must be performed at the pouring position, and the pouring time to the tundish cannot be shortened.

Further, a conventional continuous casting machine of a type in which a distributor (tundish) is poured at a preparatory position has a structure in which a tundish car is stopped at a fixed position to pour molten metal in advance. Pouring of molten steel into the tundish is completed before the start of movement, and it takes a long time from the completion of the casting to the start of pouring into the mold, causing problems such as clogging of the ladle and tundish sliding nozzle at the start of pouring. It had the drawback of being easy.

According to the present invention, the tundish is circulated and moved in one direction, and while the tundish is being poured, the tundish is poured into the mold at the same time as it reaches the pouring position while pouring the molten metal into the tundish. Shortening the preparation time and shortening the time from the completion of pouring to the tundish until the start of casting,
It is an object of the present invention to provide a casting method and a casting device for a continuous casting machine, which improves productivity and prevents troubles such as clogging of scratches at the start of casting.

[0007]

SUMMARY OF THE INVENTION A casting method for a continuous casting machine according to the present invention comprises a ladle, a tundish and a plasma torch which are coaxially rotated in synchronization with each other from a position before the pouring position to the tundish. It is possible to perform pouring into the mold immediately after reaching the pouring position by continuing pouring and heating.

The continuous casting machine of the continuous casting machine according to the present invention is provided with a ladle turret which holds a ladle at both ends and is rotatable around the center, and a ladle turret which is concentric with the ladle turret and which is cast along a circular rail around the ladle turret. A tundish car that rotates so as to pass through the casting position; and a plasma torch that reciprocally rotates around the ladle turret from a prefilling position about 90 ° before the casting position to the casting position. The torch is inserted into the tundish on the tundish car to heat the molten steel in the tundish, and the ladle on the ladle turret is being poured from the prefilling position to the tundish. , The tundish and the plasma torch rotate synchronously to the pouring position. It is configured.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic plan view of a circulating pouring apparatus according to an embodiment of the present invention, and FIG. 2 is a vertical cross-sectional view of a ladle turret in the embodiment of FIG. The ladle turret 1 has a pair of arms 3 extending from both sides in the diametrical direction of a central swivel shaft 2, and holds the ladles 4 and 4a at the tips thereof and is driven to rotate around the swivel shaft. On the casting floor 5 below the ladle turret 1, two spaced circular rails 6 concentric with the swivel shaft 2 are installed, and a tundish car 8 equipped with a tundish 7 is mounted on the rail 6. The ladle turret 1 rotates in the same direction at the same speed as the rotation speed (angular speed). Here, the tundish car 8 is aligned so as to face the ladle 4 held by the ladle turret 1, and the molten steel in the ladle 4 is poured into the tundish 7 through the sliding nozzle 9 (Fig. 2) at the bottom of the ladle. To be done. In FIG. 1, the tundish 7 and the tundish car 8 are shown only below one ladle 4 of the ladle turret 1.
It is also aligned and arranged on the rail below the other ladle 4a. A rotary joint 10 is provided on the upper end of the swivel shaft 2 of the ladle turret 1, and is necessary for operating the tundish 7 through an inside of the swivel shaft 2 from an external supply source (not shown) and further through the rotary joint 10 and the hollow arm 11. Utilities such as gas and liquid are supplied to the tundish 7.

The tundish 7 on the tundish car 8 traveling along the circular rail 6 faces the pouring position B at a predetermined position on the rail 6, and at this position the immersion nozzle 12 at the bottom of the tundish (see FIG. 2). ) Via the lower mold 13
Molten steel is cast inside. As shown in FIG. 1, a pre-filling start position A is set at a position about 90 ° before the turning center angle of the ladle turret 1 from the casting position B, and a plasma is applied to the outside of the circular rail 6 from the pre-filling start position A to the casting position B. Running rail 1 of torch truck 14
5 is provided concentrically with the circular rail 6. The plasma torch carriage 14 carries the plasma torch 16 and reciprocates on the traveling rail 15 from the prefilling start position A to the pouring position B, but when traveling forward, that is, when moving toward the pouring position B, It moves at the same speed (angular velocity) as the dish car 8 together with the tundish car 8. Reference numeral 17 is a ladle operation deck.

A ladle 4 containing molten steel is carried by a crane or the like, held at the tip of one arm of the ladle turret 1, and held at the prefilling start position A. At the prefilling start position A, injection of molten steel is started from the ladle 4 to the tundish 7 on the tundish car 8 below the ladle 4, and at the same time, the molten steel in the tundish is heated by the plasma torch 16 and the ladle turret 1 and tundish car 8 And plasma torch trolley 1
4 are activated at the same time and move to the pouring position B at the same speed. During this movement, the pouring from the ladle 4 and the heating of the molten steel by the plasma torch 16 are continued, and the tundish 7
At a pouring position B, when a predetermined amount of molten steel is poured, the casting into the mold is started. After the start of casting, the plasma torch carriage 14 returns to the original prefilling start position A. When the ladle 4 becomes empty during casting, the ladle turret 1 is rotated to move the empty ladle 4 to the prefilling start positions A and 18
It moves to the retreat position C on the opposite side of 0 ° and is replaced with a new ladle which is previously filled with molten steel. The exchange of the ladle 4 is repeated several times to continue casting. And when it is necessary to hold and inspect the tundish 7 due to continuous casting,
The tundish car 8 is retracted together with the ladle turret 1 in the same direction as described above, that is, in the direction of the arrow in FIG. At this time, if the casting is to be continued continuously, a new tundish 7 is prepared at the prefilling start position A, and the used tundish 7 and ladle 4 are used.
Simultaneously with the evacuation of, the new ladle previously placed on the ladle turret 1 on the opposite side of the pouring position B is rotated to the prefilling start position A, and from here the new ladle 4 is poured into the new tundish 7 as described above. Start ladle 4 and ladle 4 and tundish 7 while pouring water
And, the plasma torch 16 is synchronously rotated to the casting position B, and when casting is started into the casting mold 12 immediately after reaching the casting position, while the molten steel cast in the casting mold 12 still remains. It is possible to continue casting, and continuous casting is possible. Further, when the casting is temporarily interrupted during the replacement of the tundish 7, the used tundish 7 and the ladle 4 are retracted to the retracted position, and the molten steel cast in the mold 12 is temporarily cast out of the continuous casting machine. I will pull it out. And when performing the next casting,
According to a well-known method, preparation for pouring such as insertion of a dummy bar and mold sealing is performed for the next pouring on the mold side. Also,
At the prefilling start position A during preparation for casting on the mold side, a new tundish 7 to be used for the next casting and a ladle 4 preliminarily filled with molten steel are prepared. Then, when the next casting is started, injection of molten steel from the prefilling start position A to the tundish and heating are started in the same manner as described above, and the casting is moved to the casting position B. Then, when the casting position B is reached, the casting operation is started immediately.

FIG. 3 is a schematic plan view similar to FIG. 1 of a continuous casting machine showing another embodiment of the present invention. Figure 3
In FIG. 1, the same parts as those in FIG. 1 are designated by the same reference numerals, and the duplicated description of the parts will be omitted. A tundish transfer carriage rail 17 is installed adjacent to the retreat position C of the tundish car 8 after the pouring operation is finished, and the tundish transfer carriage 18 is retracted on the transfer carriage rail 17. It is designed to travel back and forth from the position C to the lateral slag position D. The used tundish 7 transferred from the tundish car 8 to the transfer carriage 18 at the retreat position C is overturned by the tilting device 19 at the slag position D, and after the internal residue is discharged, the tundish is again discharged. It is returned from the dish transfer cart 18 onto the tundish car 8, where necessary maintenance / inspection is performed at the intermediate position E and moved to the prefilling start position A, and prefilling is performed from the ladle containing the new molten steel to the tundish 7. Be started.

[0013]

As described above, according to the present invention, the molten steel is cast from the ladle to the tundish while the ladle and the tundish are synchronously moved from before the pouring position. So, after reaching the pouring position,
Casting can be started immediately, and failure such as clogging of the sliding nozzle due to prefilling does not occur. Since the tundish is poured during preparation on the mold side,
The filling time on the tundish side is shortened and productivity is improved. Further, since the molten steel is heated by the plasma torch at the same time as the prefilling, the temperature of the molten steel in the tundish can be raised at the initial stage of pouring, and the quality and yield of the slab are improved. Further, since the tundish can be replaced in an extremely short time, there is an effect that continuous casting can be performed without interrupting the casting once.

[Brief description of drawings]

FIG. 1 is a schematic plan view of a circulation pouring device according to an embodiment of the present invention.

FIG. 2 is a vertical sectional view of the ladle turret cut along the turning center in the embodiment of FIG.

FIG. 3 is a schematic plan view of a circulation pouring device according to another embodiment of the present invention.

[Explanation of symbols]

 1 Ladle turret 4,4a Ladle 6 Circular rail 7 Tundish 8 Tundish car 10 Rotary joint 14 Plasma torch trolley 15 Traveling rail 16 Plasma torch 18 Tundish transfer trolley 19 Tundish tilting device A Prefilling position B Casting position C Retreat position D Discharge position

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Mitsuhiro 1-2-2 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (72) Koichi Ozawa 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe Within the corporation

Claims (2)

[Claims] 1. A ladle, a tundish and a plasma torch are arranged concentrically, and while being rotated synchronously, pouring and heating of the tundish are started from before the pouring position, and the pouring position is started. A casting method for a continuous casting machine, characterized in that casting is performed in a casting mold. 2. A ladle turret which holds a ladle at both ends and is rotatable around a center, and a tundish car which is concentric with the ladle and rotates around the ladle so as to pass through a casting position along a circular rail. And a plasma torch that reciprocally rotates around the ladle turret from the prefilling position before the casting position to the casting position, and the plasma torch is inserted in the tundish on the tundish car. The molten steel in the tundish is heated, and the pouring from the prefilling position to the tundish is performed while the ladle on the ladle turret, the tundish and the plasma torch are synchronized. Circular pouring position of continuous casting machine characterized by turning to position.