JP2527886B2 - Slab forming equipment for horizontal continuous casting equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slab for a horizontal continuous casting facility for intermittently drawing molten metal supplied from a tundish to obtain a slab for continuously casting a metal such as steel. The present invention relates to a molding device.

[0002]

BACKGROUND OF THE INVENTION In horizontal continuous casting, molten metal stored in a tundish is supplied to a mold, where it is cooled to form a solidified slab at least in the outer peripheral portion. It is carried out by intermittently withdrawing the slab formed by a drawing device provided on the downstream side of the mold. In this horizontal continuous casting equipment, the tundish and the mold are hermetically connected to each other, so that the static pressure against the molten steel is large and the contact between the mold and the solidified shell is good, so that the cooling is performed uniformly, and the slab (particularly of the circular cross section is thing)
It is widely adopted because it can be easily molded. By the way, in this horizontal continuous casting, since the tundish and the mold are hermetically connected as described above, unlike the vertical continuous casting in which the constant speed continuous drawing drive of the slab is performed, "drawing-stop-pushback" is performed. The intermittent drawing drive of the slab with "stop" as one cycle is adopted, and the disadvantage of so-called cold shut crack, which is caused by this intermittent drawing drive, easily occurs on the surface of the slab for horizontal continuous casting. It also has one side.

The mold used in this horizontal continuous casting is cooled by cooling the outer peripheral wall (often water-cooled),
At least the outer peripheral portion of the molten metal supplied to the hollow part of the cylindrical mold is solidified to form a slab, and the solidified layer thickness of the slab that exits this mold gradually increases, and the hardness of the slab is increased accordingly. Also increases. Therefore, the reduction for forming the slab into a predetermined shape is often performed at the stage where the slab is relatively soft because the thickness of the solidified layer is thin. Further, in continuous casting of high alloy steel and high carbon steel, troubles such as breakage may occur in the rolling process after continuous casting due to concentration of low melting point substances such as carbon and sulfur in the center of the slab at the solidification end. For this reason, it is performed that the low melting point substance that is pressed down near the solidification completion point (crater end) and concentrated in the center is discharged to the upstream side to prevent segregation.

For example, Japanese Unexamined Patent Publication (Kokai) No. 62-81255 discloses a "casting strand forging apparatus" as shown in FIG. 7, which is an anvil-shaped rolling down apparatus 30 for casting. It is provided on the upstream side of the drawing device, and this forging device is fixed on the ground. For this reason, the driving reaction force at the time of reduction molding becomes a load on the slab withdrawing apparatus, and it is necessary to increase the drive capacity of the slab withdrawing apparatus. In this case, in a vertical continuous casting facility in which a slab is cast at a constant speed, even if the drive capacity of the drawing device is increased to support the drive reaction force at the time of molding the slab, it does not cause a problem. But,
In horizontal continuous casting in which the slab is intermittently drawn, solidification is started at the break ring end, so that the quality of the slab is adversely affected to some extent as the drive capacity of the drawing device increases.
In horizontal continuous casting, which is generally intermittently drawn,
This is because a servo motor with high accuracy is used, but few have large capacity and high accuracy. Further, since the speed of the cast piece in the rolling down device and the speed of the cast piece in the subsequent drawing device are different, it is difficult to control this, and the positional accuracy is likely to deteriorate. Therefore, the occurrence of slab surface defects (cold shut cracks) is easily increased. Further, since the forging device is a fixed type on the ground, the device becomes large in size, it is difficult to maintain the accuracy of the drawing stroke and the pushing-back stroke by the drawing device, and the quality of the cast piece is more likely to deteriorate (cold shut cracks deteriorate).

The present invention has been made in view of the above problems of the prior art, and its object is to position a slab by the intermittent drawing device without increasing the drive capacity of the intermittent drawing device. An object of the present invention is to provide a slab forming apparatus for a horizontal continuous casting facility that is easy to control and has high positional accuracy.

[0006]

In order to achieve the above object, the present invention provides a tundish and a mold which are hermetically connected to each other through a break ring, at least the mold is fixed to the ground, and a slab is intermittently drawn by a drawing device. A slab molding device installed on the upstream side or downstream side of the drawing device of the horizontal continuous casting equipment to be drawn, in a frame on a trolley capable of traveling in the casting direction on the floor surface during non-casting The slab molding rolls are rotatably attached to the upper and lower parts and both sides by a driving device, and the slab molding rolls on the upper and both sides in the frame can be rolled down by a rolling down cylinder. A position detection device to detect the position is provided, and the upper slab forming roll is pressed down by the pressing cylinder to turn the upper and lower slab forming rolls into slabs. The first invention is a slab forming apparatus for a horizontal continuous casting facility, characterized in that the slab is formed by pressing down the slab forming rolls on the upper and lower sides and both sides of the tundish and the mold. Is sealedly connected via a break ring, at least the mold is fixed to the ground, and the cast product is installed on the upstream side or the downstream side of the drawing device of the horizontal continuous casting equipment in which the cast product is intermittently drawn by the drawing device. The supporting rolls are attached to the upper and lower parts of the frame on the carriage that can travel on the floor surface in the casting direction when not casting, and the upper supporting rolls can be rotated by the drive device and by the pressure reduction cylinder. Can be rolled down,
Further, a pressing press is attached to each of the upper and lower parts and both sides of the frame, and a position detecting device for detecting the position in the casting direction is provided on the trolley, and the upper supporting roll is pressed down by a pressing cylinder. Horizontal continuous, characterized in that the lower support roll, the upper / lower lowering press and the both sides of the lowering press are mounted on the slab to form the slab while the upper / lower and both sides of the lowering press are pressed down. A slab forming apparatus for casting equipment is a second invention.

In the present invention, the casting direction means both the pulling direction and the pushing back direction of the slab by the intermittent drawing device.

[0008]

According to the first aspect of the invention, the upper, lower and both sides of the slab forming roll are mounted on the slab by pressing the upper slab forming roll with the reduction cylinder. Since the slab can be molded while pressing down the slab forming roll, the driving reaction force at the time of molding does not become a load of the drawing device, and it is not necessary to increase the driving capacity of the drawing device. Moreover, the slab forming rolls on the upper, lower and both sides are rotated by the drive device to move the slab forming rolls in the casting direction according to the casting speed of the drawing device, while the position is adjusted by the position detecting device. By doing so, the slab can always be molded at a constant position between the roller tables.

According to the second aspect of the invention, the upper and lower support rolls, the upper and lower reduction presses, and the both side reduction presses are mounted on the slab by lowering the upper support rolls by the reduction cylinder. -A slab can be formed while pressing down the lower and both side pressing presses. Moreover, if the position detection device adjusts the position while rotating the upper support roll by the drive device to move the upper support roll in the casting direction in accordance with the casting speed of the drawing device, a constant position between the roller tables is always maintained. The slab can be molded with. Furthermore, according to the second aspect of the present invention, since the slab forming pressing press is provided separately from the slab supporting roll, the molding amount per time is controlled within the allowable operating range of the slab pressing device. By performing molding a large number of times, it is possible to reduce internal cracking of the slab at the time of drafting and to increase the amount of molding.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

(Example 1) FIG. 1 is a side view of a horizontal continuous casting facility equipped with a cast molding apparatus of the present invention. In the figure, 1 is a tundish,
A mold 3 is hermetically connected to the tundish 1 via a break ring 2. Reference numeral 4 denotes a drawing device, which is a slab 5 having a substantially rectangular cross section, which is delivered from the mold 3.
Along the support roll 6 and pull out intermittently in the horizontal direction. A cast molding device 7 is installed subsequent to the drawing device 4. Reference numeral 8 denotes a cutter, which cuts the cast piece 5 formed by the cast piece forming device 7 into a predetermined length, and the cut piece 5 is supplied to a cooling bed (not shown) via a roller table 9. It Of the arrows in the figure, the arrow pointing to the right indicates the drawing direction of the slab by the drawing device, and the arrow pointing to the left indicates the pushing direction of the slab by the drawing device. The meaning of the arrow is the same in FIGS. 3 and 4 described below.

As shown in FIG. 2, the slab forming apparatus 7 has four slab forming rolls 10A, 10B, 10C and 10D vertically and horizontally so as to surround the slab 5, as shown in FIG.
3 is attached to the frame 11a, and these four cast piece forming rolls are installed one by one in front and behind the frame 11a as shown in FIG. 3 (in the horizontal direction on the paper surface of FIG. 3). Slab forming rolls are not shown). Figure 2
, 12A, 12B, 12C, 12D are motors with a speed reducer, which are feeders for the slab forming rolls, 13A, 1
3B and 13C are reduction cylinders, and the lower cast molding roll 10D is not provided with a reduction cylinder. Regarding the relationship between each reduction cylinder and the slab forming roll, for example, the roll 10A will be described as a representative. As shown in FIGS. 2 and 3, the engagement pin 16 is inserted into the member 15 at the tip of the rod 14 of the reduction cylinder 13A. And the engaging pin 16
Is connected via an arm 17 to an arm 18 which is swingably supported by a frame 11a of the truck around a support shaft 18a. The drive shaft 1 for the arm 18 and the cast molding roll 10A is connected to the arm 18.
9 is connected. The relationship between the other reduction cylinders and the slab forming roll is also the same, so the description thereof will be omitted.

In FIG. 2, reference numeral 20 denotes a dolly 11 when not cast.
Geared motor that drives the machine to the proper position in the casting direction, 2
Reference numeral 1 is a wheel for traveling the bogie, and 22 is a rail laid on the floor surface.

As shown in FIG. 3, a position detecting device 23 is attached to the lower portion of the carriage 11 as a means for correcting the position of the slab forming device in the casting direction to the proper position during casting.

Next, a method of forming a cast piece using the cast piece forming apparatus having the above-mentioned structure will be described with reference to FIGS. At the start of casting, the slab forming device 7 has a slab 5
A dummy bar is set in place of the slab, and normally this dummy bar has a smaller cross section than the slab, each reduction device is opened, and the wheels 21 of the carriage 11 are mounted on the rails 22 and set at predetermined positions on the ground (see FIG. 1). Support rolls 6a and 6b
It is in a stationary state at a position approximately in the middle of. Then, after the casting is started, the molten metal supplied from the tundish 1 to the mold 3 via the break ring 2 is cooled from the outer periphery to form a solidified layer having a constant thickness. The slab 5 reaches the drawing device 4 while further increasing the thickness of the solidified layer. Then, the slab 5 reaches the slab molding device 7 on the downstream side while undergoing the intermittent withdrawal of "pull-stop-push-back-stop" by the drawing device 4. At this time, the reduction cylinder 13A is operated to move the truck 11 away from the ground, and then the reduction cylinder 13A is activated.
B and 13C are operated to start the reduction molding. Since the slab forming rolls 10A and 10D are connected via the frame 11a, when the downward pressing force by the reduction cylinder 13A is applied to the upper slab forming roll 10A, the lower slab forming roll 10D As a result, an upward pressing force corresponding to the above is generated, so that the slab 5 is pressed down in the vertical direction. At the same time, the pressing cylinders 13B and 13C perform lateral pressing on the slab 5. Thus, the slab 5 is formed by pressing, and each slab forming roll is provided with driving devices 12A to 12D for traveling movement. The moving speed of the slab forming roll by each driving device is Since it is controlled so as to correspond to the average speed output from the drawing device 4, the slab forming device 7 executes the forming operation as if it were stationary. Then, when the molding position of the slab molding device 7 exceeds a certain range between the support rolls 6a and 6b, the moving speed of the slab molding roll is adjusted by a signal from the position detection device 23 to change the position. Since it is corrected, it is possible to always perform the cast molding operation at a fixed position.

In the present embodiment, the slab forming rolls for reduction forming are provided on the four surfaces covering the entire surface of the slab, but the forming rolls are provided only on the upper and lower two surfaces depending on the shape to be formed. You can Furthermore, the shape of the slab is not only a square cross section,
It may have a circular cross section.

Further, driving devices 12A, 12 for traveling and moving.
B, 12C, and 12D are not necessary for four surfaces, and one unit is also possible.

(Embodiment 2) Next, another embodiment will be described with reference to FIGS. This embodiment shows a case where the reduction molding device and the feeding device are separated. As shown in FIG. 4, a pair of upper and lower support rolls 25 and 26 are installed in front of and behind the frame 11b of the bogie, and a roll-down cylinder 24 is disposed on the support roll 25 above the cast slab 5. However, the lower support roll 26 is not provided with a reduction cylinder. Further, as shown in FIG. 5, a driving device (motor with reduction gear) 27 for traveling is arranged on the upper support roll 25, but a driving device for traveling is arranged on the lower support roll 26. Not set up. Furthermore, there is no support roll in the lateral direction of the slab 5. Each of these support rolls has a function of supporting and moving the slab, and is used to keep the pressing press at a constant position against the driving reaction force of the pressing press described later. As shown in FIG. 6 for molding a slab, the pressing presses 28A,
B, 28C, 28D are arranged, and each reduction press is provided with reduction cylinders 29A, 29B, 29C, 29D. In addition, the same components as those in FIGS.

In the case of this embodiment, in addition to the effect of the above embodiment, an effect that a larger molding can be performed can be expected. This is because the amount of reduction per roll at a certain roll diameter is limited to a certain value or less due to the physical properties of the slab, and in the case of the examples shown in FIGS. 1 to 3, they were installed before and after the frame of the truck. The slab can be formed only by the amount of reduction within a range possible by the two-stage reduction by the slab forming roll. In order to increase this reduction amount, there is a method of increasing the roll diameter or increasing the number of reduction stages (increasing the slab forming apparatus), but increasing the roll diameter more than necessary due to equipment restrictions and cost, It is not possible to install multiple cast molding devices. On the other hand, in the present embodiment, the rolling is performed in small steps within the allowable operating range of the slab forming apparatus corresponding to the casting speed of the drawing apparatus (the reduction amount per one time of the reduction press is reduced to reduce the number of times. By doing so, large reduction is possible, and since the amount of reduction per time is small, it is possible to prevent internal cracking that tends to occur inside the slab.

The installation position of the cast molding apparatus is as follows.
As shown in Fig. 1, it is better to install it on the downstream side of the drawing device.
It is more preferable that the change of the casting speed due to the change of the slab cross-sectional area before and after the molding device does not affect the control of the casting speed by the drawing device so much, but if the reduction amount is small, the adverse effect is small, so the slab molding device Can also be installed upstream of the drawing device.

[0021]

Since the present invention is configured as described above, it has the following effects. According to the first aspect of the invention, since the cast product can be molded with the cast product forming apparatus mounted on the cast product, the driving reaction force at the time of cast product formation does not act as a load on the drawing device, and the drawing device is driven. There is no need to increase the capacity. Further, this allows a sufficient margin for the capacity of the drawing device, so that the control accuracy of the drawing device is not hindered, and the position accuracy can be maintained satisfactorily.
Furthermore, since the slab can be molded while mounted on the slab,
Even if the size of the slab cross-section is changed, it is not necessary to change the mounting positions of the slab forming roll and the front and rear equipment.

Further, since the slab forming roll can be moved in the casting direction, if the position adjusting device adjusts the position while moving the slab forming roll in accordance with the casting speed of the drawing device, the roller table is always moved. It is possible to form a slab at a fixed position in between.

Furthermore, since the slab forming roll can be moved in the casting direction while being mounted on the slab, the resistance of the slab forming roll during the traveling movement does not affect the drawing operation of the drawing device.

According to the second aspect of the present invention, since the slab forming device and the slab feeding device are separately provided, in addition to the above effects, the forming amount per one time by the pressing press is controlled to form a large number of times. By doing so, internal cracking of the slab at the time of reduction molding can be reduced, and large reduction can be achieved.

Further, according to the present invention, since the slab forming apparatus is provided separately from the slab drawing apparatus, the intermittent drawing operation of "drawing-stop-pushback-stop" can be accurately executed. At the same time, slab molding is possible independently of the drawing pattern of the drawing device, and if the slab forming roll is moved according to the casting speed of the drawing device, a series of operations of "drawing-forming" will be performed smoothly. be able to.

[Brief description of drawings]

FIG. 1 is a side view of a horizontal continuous casting facility equipped with the slab forming apparatus of the present invention.

FIG. 2 is a front view of the cast molding apparatus of the present invention, taken along line A- of FIG.
FIG.

FIG. 3 is a side sectional view of the cast molding apparatus of the present invention.

FIG. 4 is a side sectional view of another embodiment of the cast molding apparatus of the present invention.

5 is a view taken along the line BB of FIG.

FIG. 6 is a sectional view taken along line CC of FIG. 4;

FIG. 7 is a perspective view of a conventional cast molding apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tundish 2 ... Break ring 3 ... Mold 4 ... Extraction device 5 ... Slab molding device 7 ... Slab molding device 10A, 10B, 10C, 10D ... Slab molding roll 11 ... Trucks 11a, 11b ... Frame 23 ... Position detection device 28A, 28B, 28C, 28D ... Reduction press

Claims (2)

(57) [Claims] 1. A and tundish and the mold is sealed connected via a break ring, upstream of the at least mold the cited disconnect device of the horizontal continuous casting equipment piece cast fixed to the ground is intermittently withdrawing the extracting device or Installed on the downstream side
It is a slab forming device that is placed , casting on the floor surface when not casting
Above the inside of the frame on the bogie that can travel in any direction
Drive device for slab forming rolls at the bottom and both sides
Rotatably attached by the above, and the upper part inside the frame
And the slab forming rolls on both sides are pressed by the pressing cylinder.
It is possible to lower and to detect the position in the casting direction on the trolley.
Is equipped with a position detection device to lower the upper slab forming roll.
Slabs on the upper and lower sides and both sides by pressing down with a binder
By mounting the molding roll on the slab,
The slab can be formed by pressing down the slab forming rolls on both sides.
And a slab forming device for horizontal continuous casting equipment. Wherein the tundish and the mold is sealed connected via a break ring, upstream of the at least mold the cited disconnect device of the horizontal continuous casting equipment piece cast fixed to the ground is intermittently withdrawing the extracting device or Installed on the downstream side
It is a slab forming device that is placed , casting on the floor surface when not casting
Above the inside of the frame on the bogie that can travel in any direction
Attaching a support roll to the lower part and driving the upper support roll
It can be rotated by the device and can be reduced by the reduction cylinder.
In addition, on the top and bottom and both sides of the above frame
Attaching a reduction press to each of the above trucks
A position detection device to detect the position
Upper and lower support by rolling down the roll with a rolling down cylinder
Roll down the upper and lower pressing presses and press down both sides.
As it is mounted on a slab, the upper and lower parts and both sides are rolled down.
A cast molding apparatus for a horizontal continuous casting facility, characterized by molding a cast piece while pressing down a press .