JPH0645820B2 - Equipment for removing molten steel suction pipe in vacuum degassing equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to an apparatus for removing slag from metal and slag attached to a suction pipe for molten metal in a vacuum degassing facility such as a DH furnace or an RH furnace.

[Conventional technology]

The DH furnace, the RH furnace, and the like are equipped with a refractory cylindrical suction tube in which molten steel is immersed. When this suction pipe is used by repeatedly dipping it in molten steel several times, molten steel ingot and slag adhere to the outer peripheral surface each time, and the ingot and slag form a cylindrical layer of several layers. Stick to it.

Various proposals have heretofore been made in order to remove such molten steel ingots and slag. For example, in Japanese Utility Model Publication No. 52-56322 and Japanese Patent Publication No. 63-26172, a device for removing slag adhered to a suction pipe is started. These devices include a hollow cylindrical cutter that covers the outer circumference of the suction tube or a cutter that can move and swivel along the outer circumference,
The slag is cut by these cutters.

In addition, as described in, for example, Japanese Examined Patent Publication (Kokoku) No. 45-23207, there is one that incorporates a combustion injection nozzle for preheating slag and a cutting tool to remove the slag.

[Problems to be solved by the device]

In the former device, a sufficient effect is obtained for removing slag by slag cutting with a cutter. However, there is no cutting ability for the molten steel ingot which is adhered in a layer together with the slag, and there is a functional limitation that the molten steel ingot cannot be removed. In addition, the cutter is likely to bite between the metal and the refractory material, and the work of pulling out this material has also been a heavy burden.

On the other hand, the latter device is also intended to remove only slag, and no measures have been taken against the metal. In addition, although slag preheating certainly achieves reduction of cutting load and efficiency improvement based on this, it takes time to preheat slag, and a cutting allowance per cut is applied to the entire circumference of the cutting tool. Need to be small. Therefore, the working time becomes long, and there is a problem in practicality in terms of operating rate and productivity.

Furthermore, the conventional slag removal work is performed in such a manner that the removed slag is once collected in a slag receiver and then discarded by a crane or the like each time. For this reason, there is a lot of waiting time loss for cranes and the like, which is not always perfect in terms of work efficiency.

As described above, the conventional techniques are not limited to the removal of slag and the removal of adhered metal. For this reason, in order to cut and remove the adhered metal, there is no choice but to rely on manpower such as fusing work using oxygen or chisel. Therefore, in particular, there are problems in terms of safety and the like, the burden on the operator is increased, and it is also an obstacle to improvement of productivity.

Therefore, it is an object of the present invention to efficiently and safely cut and remove slag, including metal, to reduce the work load and improve productivity.

[Means for Solving the Problems]

The molten steel suction pipe slag removing device of the present invention comprises a turntable that can swivel directly under the suction pipe and can move up and down in the axial direction, and a cutting device and a cutting device equipped on the turntable. The apparatus comprises a cutter for making a longitudinal slit in a layer of molten steel ingot and slag around a suction tube when the turntable is raised, and the cutting apparatus further comprises:
A cutting blade for cutting the layer with a vertical cutting stroke when the turntable is raised is provided.

[Action]

When the turntable is raised, the cutter of the cutting device cuts slits from the bottom to the top of the layer of molten steel and slag adhering around the suction tube. With respect to the slits, if the turntable is rotated to change the position of the cutter, a plurality of slits can be cut in the circumferential direction of the suction tube, and the layer is divided into a plurality of lines by these slits.

If you set the cutting blade of the cutting device after engraving the slit,
As the turntable rises, the cutting blade scrapes the layers from bottom to top. And since the layer is divided into multiple strips by the cutter of the cutting device, there is no cutting load on the cutting blade from the outer layer beyond the slit, the cutting resistance is reduced and the layer is quickly peeled off. It can be removed.

〔Example〕

FIG. 1 is a front view showing a working condition for a suction pipe of a DH furnace using the slag removing apparatus of the present invention, and FIG. 2 is a plan view.

In the figure, a slag removing device is installed on a working floor 52 immediately below a suction pipe 51 protruding from the bottom surface of a DH furnace 50. This slag removing device is configured with a trolley 1 that can travel on a work floor 52 as a base, and an annular turntable 2 that can move up and down toward a suction pipe 51 and can rotate around the center, such as a cutting device and a cutting device. It is equipped as a mounting part.

The turntable 2 is rotatably mounted on a deck 3b fixed to the rods 3a of a plurality of lifting cylinders 3 fixed to the carriage 1, and moves up and down as the rods 3a move forward and backward. Also,
A connecting mechanism 4a is provided between the deck 3b and a mechanical means such as a pinion rack for rotating the turntable 2 around its center or a fluid mechanism using hydraulic pressure, and the drive device 4 is attached thereto. Connected.

On the upper surface of the turntable 2, there is provided a cutting device 5 for cutting the slag and the molten steel ingot attached to the outer peripheral surface of the suction pipe 51 from the lower end and dividing the slag into a plurality of strips. A cutting device 6 for shaving and removing the slag and the molten steel ingot from the lower end is arranged. As shown in FIG. 2, the cutting device 5 and the cutting device 6 are arranged adjacent to each other by three, respectively.

FIG. 3 is a view of the cutting device 5 as viewed in the direction of arrows I-I in FIG.

The cutting device 5 pivotally mounts an adapter 7a on a base frame 5a fixed to the turntable 2 by a pin 7b so as to be rotatable in a vertical plane, and a cutter 7 is detachably attached to the adapter 7a. Further, in order to lay the cutter 7 to the position shown by the alternate long and short dash line in the figure, the attitude setting cylinder 8 is pivotally attached to the base frame 5a, and its rod 8a is connected to the adapter 7a. The cutter 7 has a flat head having a thin planar shape because the slag and the molten steel ingot attached to the peripheral surface of the suction pipe 51 are slit from the lower end.

The cutter 7 may be vibrated or an intermittent impact force may be applied. In this case, adapter 7a
Instead, the cutter is supported by a cylinder or the like, and the cutter 7 is moved back and forth in the axial direction by the reciprocating movement of the cylinder rod, or the cutter 7 is intermittently pushed out by a strong force. Thus, by imparting vibration or impact force to the cutter 7, it is possible to increase the frame breaking force against the slag and the molten steel ingot. As a mechanism for giving vibration or intermittent impact to the cutter 7, for example, a commercially available breaker for civil engineering, a hammer, a pick, or the like can be substituted.

FIG. 4 is a view of the cutting device 6 as viewed in the direction of arrow II-II in FIG.

The cutting device 6 has a slider 9a slidably mounted on the upper surface of a base plate 6a fixed to the turntable 2, and a cutting blade 10 attached to the tip of this slider 9a. The slider 9a is connected to the rod 9c of the position setting cylinder 9b for retracting the cutting blade 10 and setting the cutting depth.
The cutting blade 10 can be moved in the radial direction of the turntable 2 by advancing and retracting 9c.

Returning to FIG. 1 and FIG. 2 again, the chute 11 is arranged so as to penetrate the annular turntable 2. The chute 11 extends from directly below the suction pipe 51 to the trolley 1 part and has a lower end as a hopper 11a, which receives slag and crushed pieces of molten steel ingot during cutting and cutting work as they are, and hopper 11
Recover from a.

The removal of slag and molten steel ingot around the suction pipe 51 by the slag removing device having the above configuration is performed as follows.

First, the trolley 1 is moved to turn the turntable 2 into the suction pipe 51.
Set to a position that is almost coaxial. Next, the cutter 7 of the cutting device 5 is set to the posture indicated by the alternate long and short dash line in FIG. 3, and the slider 9a of the cutting device 6 is set to the retracted position to retract the cutter 7 and the cutting blade 10. After this, the lifting cylinder 3
Drive the rod 3a to advance, and turntable 2
Is moved up to near the suction pipe 51.

The attitude of the cutter 7 of the cutting device 5 is adjusted according to the thickness of the layer of slag and molten steel ingot attached to the suction pipe 51. This is done by adjusting the bite amount of the cutter 7 by the stroke of the rod 8a of the attitude setting cylinder 8.
For example, when the thickness of the layer is large, the cutting load increases when the bite amount is too deep, and therefore the cutting may be performed in several steps.

After the attitude of the cutter 7 is set, the lift cylinder 3 is driven again to raise the turntable 2, and the rise causes the cutter 7 to bite into the layer of slag and molten steel. By this work, vertical slits S are incised at three points on the layer during one lifting operation of the turntable 2. Then, when the depth of cut is insufficient in one upward movement due to the thick layer, the turntable 2 is once lowered to bring the cutter 7 to the side of the layer, and the turntable 2 is raised again to deepen the depth of cut. To do.

After that, the turntable 2 is rotated by the driving device 4, the cutting device for the cutter 7 is changed, and the cutting is cut in the layer in the same manner as described above. And, if necessary, in order to increase the number of places to make a cut, turntable 2
Rotate to engrave a slit in a new position.

As described above, not only the raising / lowering operation of the cutter 7,
You may make it hold | maintain to a cylinder and give a vibration or an intermittent impact force. In this case, not only the cutting force when the cutter 7 rises, but also the vibration and impact force of the cutter 7 can perform the cutting work while crushing the slag and the molten steel ingot, thus improving the efficiency.

After the slits S are formed in the layer of the slag and the molten steel ingot in the vertical direction to divide into a plurality of strips, the cutter 7 is returned to the retracted position shown by the diagonal lines in FIG. Then, the position of the cutting blade 10 of the cutting device 6 is set by the position setting cylinder 9b. Even with this setting, the cutting blade 10 will come to a position according to the layer thickness,
If the layer is thick, cut it several times. After the position of the cutting blade 10 is set, when the turntable 2 is raised by the elevating cylinder 3, the cutting blade 10 also rises integrally and cuts from the lower end of the layer. When the layer is thick, the turntable 2 is once lowered and then the slider 9a is moved to the right side in FIG. 4 to increase the cutting allowance, and the turntable 2 is again raised to perform new cutting.

In the cutting work by the cutting device 6, the slag and the molten steel base metal layer are divided in advance by the cutting device 5 into a plurality of cuts in the circumferential direction, so that the cutting load can be reduced. That is, when the cutting blade 10 cuts while corresponding to the slit S, for example, the cutting resistance received from the layer outside the slit S does not act on the cutting blade 10.
For these reasons, the load on the cutting blade 10 is smaller than in the case of cutting without the slit S, and it is not necessary to increase the output of the lifting cylinder 3, and the rigidity of the entire device is adequate and can be endured. Therefore, the device can be simplified. Needless to say, if the cutting device 5 is operated so that several slits S are engraved in the width of the cutting blade 10, the cutting load is further reduced.

Further, since the slit S is preliminarily cut and cut by the cutting blade 10, even if the cutting blade 10 is bitten between the layer and the tube wall of the suction pipe 51 due to a large amount of bite, the layer is divided into a plurality of lines. Therefore, the resistance when pulling out the cutting blade 10 is reduced. Therefore, the load of external force on the cutting blade 10 can be suppressed,
Damage and breakage are also prevented. Then, in the case where the layer is thin, if the slit S is not required to be cut by the cutting device 5, the slag and the molten steel ingot can be peeled off and removed using only the cutting device 6, and the work depending on the adhesion situation is also possible. Becomes

Further, the slag and the crushed pieces of molten steel ingot generated during the cutting and cutting operations fall due to their own weight, fall into the chute 11, and are recovered and removed from the hopper 11a. Therefore, it is not necessary to equip the crane as in the conventional case, and the time for waiting the crane is not required, and the working efficiency is improved.

If the layer of slag and molten steel ingot is thick, the cutting device 5
Therefore, the slit S may be cut to a certain depth, the layer thickness may be reduced by the cutting device 6, and the side cutting device 5 may newly perform slitting for cutting.

〔The invention's effect〕

In the present invention, a slit is formed in a layer of slag and molten steel ingot by a cutting device to divide the layer into a plurality of strips in the circumferential direction of the suction pipe, and then the layer is scraped off by a cutting device. Therefore, the cutting load on the cutting blade is small because the layer is divided, and the layer can be reliably peeled and removed by quick cutting. Therefore, the removal work including the molten steel ingot can be mechanically performed as in the conventional case, and the safety is markedly improved and the efficiency is promoted as compared with the manual work. And the durability of the cutting edge is improved by reducing the cutting load, and the rigidity of the entire position may be moderate,
It can be suitably used as a simplified facility.

[Brief description of drawings]

1 is a front view showing a working condition of the slag removing device of the present invention, FIG. 2 is a plan view, FIG. 3 is a view of a cutting device as viewed in the direction of arrows I-I in FIG. The drawing is a view of the cutting device viewed in the direction of arrow II-II in FIG. 1: Carriage 2: Turntable 3: Lifting cylinder, 3a: Rod 3b: Deck 4: Drive device, 4a: Connecting mechanism 5: Cutting device, 5a: Base frame 6: Cutting device, 6a: Base plate 7: Cutter, 7a : Adapter 7b: Pin 8: Posture setting cylinder, 8a: Rod 9a: Slider, 9b: Position setting cylinder 9c: Rod 10: Cutting blade 11: Chute, 11a: Hopper 50: DH furnace, 51: Suction tube 52: Work Floor S: Slit

Front page continued (72) Inventor Shigeo Tsuruoka 1 Kimitsu, Kimitsu-shi, Chiba Shin-Nippon Steel Co., Ltd.Kizu Steel Works (72) Inventor Shigeru Enomoto Kimizu, Kimitsu-shi, Chiba Nippon Steel Co., Ltd. Kimitsu Co., Ltd. Inside the ironworks

Claims (1)

[Claims] 1. A turntable that can swivel directly below a suction pipe and can be moved up and down in an axial direction, and a cutting device and a cutting device mounted on the turntable, wherein the cutting device raises the turntable. Occasionally, a cutter for engraving a vertical slit in a layer of molten steel ingot and slag around the suction pipe is provided, and the cutting device further cuts the layer with a vertical cutting stroke when the turntable rises. An apparatus for removing molten steel suction pipe in a vacuum degassing facility, which is equipped with a cutting blade.