JPH06104272B2 - Electric control device for stopper for casting nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a continuous or semi-continuous casting in which a molten metal is supplied to a mold having an open upper end used when continuously casting a slab of metal or alloy. The present invention relates to an electric control device for a stopper for a dipping nozzle, and more particularly to an electric control device for a stopper for a dipping nozzle, which is suitable for a continuous or semi-continuous casting method for supplying molten metal to a mold having a large number of strands.

[Prior art] The continuous casting method is to inject the molten metal in the tundish, or the molten metal discharged from the melting furnace into the gutter into a water-cooled copper mold, and cool it by the mold to solidify the molten metal sequentially, and continuously cast the molten metal from the mold. This is a method of pulling out a slab.

In order to stably cast a slab with few casting defects in a continuous or semi-continuous casting method, heat is removed uniformly in the mold,
It is also possible to sufficiently supply the mold flux that covers the upper part of the molten metal to maintain the lubricity of the mold and the slab, and to keep the amount of molten metal supplied to the mold constant to prevent the entrainment of the mold flux in the slab. is important.

Generally, as a mold for continuous or semi-continuous casting of metal or alloy slab, a short penetrating mold composed of a pair of opposed mold short pieces and a pair of mold long pieces is used.

When the molten metal is supplied from the tundish or the gutter into the mold, an immersion nozzle is attached to the lower part of the tundish or the gutter, and the molten metal is ejected from the lower part of the nozzle and injected into the mold.

Conventionally, there are several types of jet nozzle shapes of this immersion nozzle, and a nozzle suitable for the type of molten metal to be cast and the shape of the mold is used. For example, when casting a slab cast of a copper-based alloy by a continuous or semi-continuous casting method, the casting surface of the cast,
In particular, the use of the inverted T-shaped two-hole nozzle 1 shown in FIG. 1 has become common due to the state of pinholes generated inside the slab.

This nozzle 1 generally has a cylindrical jet port 2 along the center line of the vertical cross section in the casting direction. The jet port 2 is a tundish so that the molten metal jets in parallel to the long side of the mold 3. Or it is attached to the gutter 4.

A nozzle stopper 5 is provided for the nozzle 1 as shown in FIG. 5, and the conventional nozzle stopper 5 is operated up and down by an air cylinder or a hydraulic cylinder 6 attached to a tundish or a gutter 4. It has become so.

Further, as this type of apparatus, there are JP-A-46-4358 and JP-A-
Those described in JP-A-46-5501, JP-A-49-92631, JP-A-50-142432 and the like are known.

[Problems to be Solved by the Invention]

However, in any of the above conventional nozzle stopper control devices, the nozzle stopper is directly moved up and down by the air cylinder or the hydraulic cylinder to open and close the nozzle to control the molten metal supply amount. When the center of the nozzle and the nozzle stopper deviate due to the weight and high heat of the molten metal, the uniform supply of the molten metal to each mold cannot be controlled.

Further, the nozzle stopper needs to be quickly fully opened or fully closed at the start of casting and at the end of casting, but the conventional control device has a drawback that some time lag occurs.

Furthermore, in the conventional controller, when the number of strands (the number of ingots that are cast at the same time) becomes large, it is important to keep the molten metal surface of each mold constant in order to make the quality of each slab uniform, Therefore, it is necessary to finely adjust each nozzle stopper opening independently, but there is a problem that the operation is difficult.

Further, there is a problem that fluctuations in the molten metal surface in each mold lead to intensification of molten metal convection, resulting in deterioration of the quality of the slab due to the inclusion of flux.

The present invention has been made in view of the above circumstances, and has a simple structure and can easily operate a large number of nozzle stoppers simultaneously or independently to maintain a constant molten metal level in each mold. An object of the present invention is to provide a controller for a continuous or semi-continuous casting stopper that can control the nozzle stopper opening.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention is used for a continuous or semi-continuous casting nozzle, and each of a plurality of nozzle stoppers composed of a plug portion at the tip, a male screw portion in the middle, and a rotary operation portion at the top are provided. A nozzle stopper in which a male screw portion is screwed to each of a plurality of female screw portions provided on the horizontal rod of a vertically rotatable support body composed of a horizontal rod and supporting rods provided at both ends thereof. The electric control device for controlling the rotation of each nozzle stopper is equipped with a drive motor at the upper part, and the drive shaft connected to the lower output shaft of each drive motor is inside a cylindrical guide case. A transmission shaft that extends and has a transmission shaft that transmits a rotational force is slidably fitted in the vertical direction, and the lower end of the transmission shaft has a universal join provided with a compression coil spring on the outer circumference. It is characterized in that it can be fitted into the fitting part above each nozzle stopper through the parts, and the above-mentioned drive motors can keep the molten metal level in each mold constant by the molten metal level sensor and signal. It is characterized by being controlled independently so as to keep each.

[Action]

Next, the operation of the present invention will be described. When a continuous or semi-continuous casting is started, a tundish or a trough in which the tip of the stopper body of the nozzle stopper communicates with the nozzle of the support that supports a large number of nozzle stoppers. It is rotated right above a large number of openings provided in the bottom portion, one transmission shaft is pulled down from the guide case, and the lower end is fitted into the fitting portion above the nozzle stopper by fitting.

When the drive motor is subsequently driven to rotate, the drive shaft is rotated by the torque of the drive motor via the torque limiter, and the transmission shaft that is slidably fitted in the drive shaft in the vertical direction is also rotated. As a result, the nozzle stopper, the lower part of which is depressed and fitted, is rotated via the universal joint portion having the compression coil spring on the outer periphery.

Therefore, at the start of casting or at the end of casting, each nozzle stopper screwed to the support body by each drive motor is smoothly rotated through the universal joint portion having the compression coil spring on the outer periphery, and the tundish or the trough bottom portion is rotated. Many nozzle openings are closed or opened all at once.

Furthermore, when the molten metal is being injected during casting, the drive motor is controlled by the signal of the molten metal level sensor provided in each mold so as to keep the molten metal in each mold constant, and each nozzle stopper is independent. To operate.

〔Example〕

Next, an embodiment of an electric control device for a stopper for a continuous casting nozzle according to the present invention will be described with reference to the drawings.

1 to 3 show an embodiment of the present invention, FIG. 2 shows a state in which an electric control device and a nozzle stopper are connected, and FIG. The shaft is shown stored in the guide case.

In the figure, a two-hole immersion nozzle 1 has a cylindrical ejection port 2 along the center line of a vertical cross section in the casting direction. The immersion nozzle 1 is attached to the bottom of a gutter 4, and the immersion nozzle 1 A hole 4a bored in the bottom of the gutter 4 communicates with the flow passage 1a leading to the jet port 2. Alternatively, the upper portion of the hole 4a, that is, the bottom portion of the gutter 4 is formed as a funnel-shaped valve seat 4b.

On the other hand, the nozzle stopper 7 that opens or closes the valve seat 4b has a plug portion 8 made of a carbon material at its tip, an intermediate portion having a male screw portion 9, and a plurality of rods at its upper portion.
The handle portion 10 is provided with a protruding portion 10a, and a square fitting hole 10b is formed in the upper portion. The male screw portion 9 is a support body that holds the nozzle stopper 7.
It is screwed to a female screw portion 12 provided on a horizontal rod 11a of the shaft 11. Further, the support 11 is rotated about the point P by the hydraulic cylinder 13.

Reference numeral 3a indicates the molten metal in the mold 3. On the other hand, a large number of stopper electric control devices A are attached to a gate-shaped fixing member (not shown).
Are provided on the upper extension of the nozzle 1, respectively. This stopper electric control device A is provided with a drive motor 14 on the upper part, and the output shaft of the drive motor 14 has a torque limiter 15
Is connected to the drive shaft 16 via. The drive shaft 16 has a circular cross section from the connecting portion with the torque limiter 15 to the rotating bearing 17, and
It is rotatably supported by the housing 18.

The cross-sectional shape of the drive shaft 16 from the rotation bearing 17 to the tip is triangular or quadrangular.

The lower part of the housing 18 is a guide case 19, both of which have a double structure in which a heat insulating material is filled to have heat resistance, and a rotation stopper 20 is provided at the lower end thereof via an arm. Has been.

Further, a transmission shaft 22 made of a stainless steel hollow tube is connected to the drive shaft 16 via an upper and lower bearing 21 that transmits a rotational force and can slide up and down,
This transmission shaft 22 is also a double-structured pipe having a heat insulating material inside for providing heat resistance. A circular handle 23 is provided on the lower portion of the transmission shaft 22, and a lower end of the circular handle 23 is provided on the upper handle portion 10 of the nozzle stopper 7 via a universal joint portion 25 around which a compression coil spring 24 is wound. A fitting portion 26 that is fitted into the rectangular fitting hole 10b is provided so as to fit into the fitting hole 26b.

Next, the operation of this embodiment will be described.

When starting continuous casting, a funnel-shaped valve seat provided at the bottom of the gutter 4 that connects the support 11 that supports a large number of nozzle stoppers 7 to the nozzle 1 through the tip of the plug 8 of the nozzle stopper 7. When it is rotated right above 4b, the electric control device A for the stopper, the nozzle stopper 7, and the nozzle 1 are positioned on the vertical line.

After that, remove the circular handle 23 from the rotation stopper 20,
The transmission shaft 22 is pulled down from the guide case 19, and the fitting portion 26 at the lower end thereof is dropped into and fitted into the fitting hole 10b of the nozzle handle portion 10.

When the drive motor 14 is rotationally driven in this state, the drive motor 14
The drive shaft 16 is rotated via the torque limiter 15 by the rotational force of 14, and the rotational force is transmitted to the transmission shaft 22 by the vertical bearing 21, and the universal joint portion 25 around which the compression coil spring 24 is wound. Since the fitting portion 26 at the lower end is rotated, the nozzle stopper 7 is smoothly rotated, the female stopper 12 of the horizontal portion 11a of the support 11 causes the nozzle stopper 7 to rotate downward, and the nozzle plug body 8 causes the valve seat 8 to move. Block 4b.

When the molten metal is discharged to the tundish or the gutter 4 in the above-mentioned closed state, and when a certain amount is reached, the drive motors 14 are reversely rotated to simultaneously rotate and move the nozzle stoppers 7 upward to bring the mold into a fully opened state. The molten metal is supplied to the nozzle 3 through the nozzle 1, and the cast pieces successively solidified in the mold 3 are continuously drawn downward. At this time, since the compression coil spring 24 has the restoring property of the universal joint portion 25, even if the trough 4 is deformed by the weight and heat of the molten metal and the centers of the transmission shaft 22 and the nozzle stopper 7 are deviated from each other, the drive shaft 16 and the transmission shaft 16 are transmitted. The drive motor can be operated without applying excessive force to the shaft 22.
The rotation of 14 smoothly connects and the nozzle stopper 7 can be smoothly rotated.

After that, each drive motor is controlled so that the molten metal level is kept constant by an unillustrated molten metal level sensor provided in each mold 3.
Since the nozzles 14 are controlled, the nozzle stoppers 7 can be operated independently of each other, and the opening degree of each nozzle stopper 7 can be maintained at an appropriate amount. At the end of casting, each nozzle stopper 7
Can be operated all at once to be in a fully closed state.

Furthermore, according to the present embodiment, when it is difficult to continue normal operation such as breakout or nozzle clogging during operation, or failure of the electric motor, or due to work reasons, the electric control device A can be quickly operated. When retracting, the circular handle 23 under the transmission shaft 22 can be lifted to immediately disconnect the electric control device from the fitting hole 10b of the nozzle stopper 7 and store it in the upper guide case 19.

Moreover, according to the present embodiment, even when the electric control device is disconnected as described above, the rod 10a of the handle portion 10 is operated by the fishing rod 27 to control the opening degree of the nozzle stopper 7 or to close it. it can.

〔The invention's effect〕

According to the present invention described above, the transmission shaft is configured to be slidably fitted on the drive shaft to transmit the rotational force of the drive motor, and the lower end thereof is dropped into the fitting portion above the nozzle stopper. Since it is fitted, the compression coil spring has resilience in the universal joint, and even if the trough is deformed by the weight and heat of the molten metal and the transmission shaft and nozzle stopper are decentered, the drive shaft And no excessive force is applied to the transmission shaft,
The rotation of the drive motor continues smoothly and the nozzle stopper can be rotated smoothly.When performing continuous casting, the nozzle stopper is operated by the drive motor and all nozzles are fully closed or opened at the same time. It can be in a state.

Further, when the molten metal is being injected during the casting, each nozzle stopper is independently controlled by the signal of each molten metal level sensor, and the molten metal in each mold can be kept constant.

Also, in the case of operational troubles such as breakout and nozzle blockage, and failure of the electric motor, the transmission shaft can be quickly separated from the nozzle stopper, and safe operation can be performed.

[Brief description of drawings]

The drawings show an embodiment of the present invention, FIG. 1 is a side sectional view showing a usage state of the present embodiment, and FIG. 2 is a longitudinal sectional view showing a state where the present embodiment is continuous with a nozzle stopper, FIG. 3 is a vertical cross-sectional view showing the same state of separation, FIG. 4 is a vertical cross-sectional view of the joint portion, and FIG. 5 is a side cross-sectional view of a conventional example. 1 ... Nozzle, 3 ... Mold, 4 ... Gutter, 7 ... Nozzle stopper, 8 ... Plug, 10 ... Handle, 10b ... Fitting hole, 11 ... Support, 14 ... Drive motor, 16 …… Drive shaft, 19 …… Guide case, 20 …… Rotation stopper, 22 …… Transmission shaft, 23 …… Round handle, 24 …… Compression coil spring, 25 …… Universal joint part, 26 …… Fitting part.

Claims (2)

[Claims] 1. A nozzle for continuous or semi-continuous casting,
Each male screw part of a plurality of nozzle stoppers composed of a plug part at the tip, a male screw part in the middle, and a rotating operation part in the upper part is formed in a vertical direction composed of a horizontal rod and supporting rods provided at both ends thereof. An electric control device for a nozzle stopper screwed to each of a plurality of female screw portions provided on the horizontal rod of a rotatable support, and the electric control device for controlling rotation of each nozzle stopper is driven to the upper part. A drive shaft, which is equipped with a motor and is connected to the lower output shaft of each drive motor, extends in a cylindrical guide case, and a transmission shaft that transmits rotational force can slide vertically in the drive shaft. The lower end of the transmission shaft is inserted into the fitting portion above each nozzle stopper through a universal joint portion having a compression coil spring on the outer circumference so that the transmission shaft can be fitted. Electric control device for the stopper casting nozzle, characterized in that form. 2. The drive motors are independently controlled by a signal from a molten metal level sensor so as to keep the molten metal in each mold constant. Electric control device for stoppers for casting nozzles.