JPH0576657U - Slab support cooling device in continuous casting machine - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a slab supporting and cooling device capable of following solidification / shrinkage and meandering of slab [Structure] A plurality of guide rolls 1 each having a cooling support device that presses and supports each surface are arranged along the moving direction of the slab.
And a frame 2 for rotatably supporting the guide roll 1.
A jacket 4 that forms a passage for cooling water between two adjacent guide rolls and the surface of the slab, and a support bracket 7 that rotatably supports the frame near the upper end.
The hydraulic cylinder 9 urges the lower part of the frame toward the slab. A rotation center moving mechanism 15 for moving the rotation center of the frame 2 toward or away from the slab is provided, which is an eccentric pin 16 and a second rotatably driving the eccentric pin 16. It consists of a hydraulic cylinder 19.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an apparatus for supporting and cooling a slab emerging from a mold in a continuous casting machine.

[0002]

[Prior Art]

 The continuously cast metal is passed through a mold 51 which is itself cooled as shown in FIG. 8 and gradually cooled from the outer periphery. Therefore, the molten metal Ca has a cylindrical solidified shell Cb formed on the outer periphery thereof and is drawn out of the mold 51 in the form of a cast slab C in which the molten metal Ca is confined. Then, the cast slab C coming out of the mold 51 is further cooled by the support cooling device 52. At this time, the shell Cb develops with cooling, but the shell Cb immediately after coming out of the mold 51 is thin, and if there is a weak portion, it breaks due to the internal static iron pressure, and a breakout occurs in which molten metal Ca leaks out. Occurs. In addition, if the shell Cb is not uniformly cooled, cooling cracks may occur, which also causes breakout. Therefore, conventionally, when cooling the slab C coming out of the mold 51 so as not to cause breakout, the outside of the slab C is supported by the guide roll 53 (conventional example I), or the slab C is cast through high pressure water. Pressure is applied to the piece C (conventional example II). As the conventional example I, there is one disclosed in Japanese Patent Laid-Open No. 3-248753. As shown in FIG. 8, this device pulls the slab C downward while holding it with a pair of guide rolls 53 (arrow P), covers the guide rolls 53 with a jacket 54, and makes them parallel to the guide rolls. The cooling water W is made to flow. On the other hand, as the conventional example II, there are those disclosed in JP-A-62-227562 and JP-A-2-138052. In this device, for example, as shown in FIG. 9, tanks 61 are arranged on both sides of a cast piece C coming out of a mold 51 with a slight gap 60 between the cast piece C and an inner wall 62. High-pressure cooling water is jetted from the slit 63 to support and cool the slab C.

[0003]

[Problems to be solved by the device]

 However, in the conventional example I, when the slab C solidifies and contracts, or when the slab C meanders, the slab may separate from the roll 53. In such a case, there is a problem that the cooling water W leaks from the gap between the roll 53 and the cast slab C, a predetermined cooling capacity cannot be obtained, and the supporting force is lost to cause bulging. In the conventional example II, when the size of the gap 60 between the inner wall 62 facing the cast slab C and the cast slab C varies due to solidification / shrinkage or meandering of the cast slab C, the hydrostatic pressure of the cooling water also varies. However, problems such as pressure not being generated occur. Further, since it is difficult to control the hydrostatic pressure, there is a problem that if the drawing speed of the slab C is increased, the slab support cannot be appropriately performed.

In view of such circumstances, the present invention adopts a supporting method by a guide roll with which the slab support is reliable, and is capable of following the above-mentioned solidification / shrinkage and meandering of the slab, a slab supporting cooling device. The purpose is to provide.

[0005]

[Means for Solving the Problems]

 The slab support cooling device of the present invention comprises a plurality of guide rolls arranged along the moving direction of the slab, a frame rotatably supporting the guide rolls, two adjacent guide rolls, and a casting roll. It consists of a jacket that forms a passage for cooling water between the surfaces of the pieces, a support bracket that rotatably supports the frame near the upper end, and an urging means for the lower part of the frame toward the slab. Is characterized by. Further, the support cooling device of the present invention is provided with a rotation center moving mechanism for moving the rotation center of the frame toward or away from the slab, for example, an eccentric pin and means for rotationally driving the eccentric pin. Is preferred.

[0006]

[Action]

 In the present invention, the upper end of the frame supporting the guide roll is rotatably supported by the support bracket, and the lower part of the frame is constantly urged toward the slab by the urging means. Therefore, even if the slab coming out of the mold is solidified and contracted by cooling, or even if it meanders, the guide roll can constantly press the slab and reliably support it. This makes it possible to prevent breakout and bulging (a defect in which the central part of the slab bulges outward due to internal pressure). Further, since the guide roll is constantly in contact with the slab, the leakage of cooling water can be minimized. Therefore, it is possible to accurately secure the amount of cooling water for obtaining the predetermined cooling capacity and improve the cooling capacity. In the present invention, when the rotation center moving mechanism of the frame is provided, not only the lower guide roll but also the upper guide roll, especially the guide roll just below the mold, can follow the movement and change of the slab. .. Therefore, it is possible to surely support the whole of the slab, and it is possible to more surely prevent water leakage. In particular, if cooling water leaks out to the mold side, there is a risk of steam explosion, but in a device with a rotation center movement mechanism, the sealing performance between the uppermost roll and the slab is improved, so such a risk. Can be reliably prevented.

[0007]

【Example】

 Next, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a schematic front view showing an embodiment of the slab support cooling device of the present invention, and FIG. 2 is a sectional view taken along line II-II of FIG. In FIG. 1, reference numeral 51 is a mold, and a support cooling device D is arranged immediately below the mold. The support cooling device D includes a plurality of guide rolls 1 arranged on the side surface of a slab C emerging from the mold 51, and both ends of the guide rolls 1 are rotatably supported by a frame 2. .. Further, on the back surface side of each guide roll 1, a jacket for sealing between the adjacent guide rolls 1 and forming a passage 3 for cooling water having a trapezoidal cross section between the guide rolls 1 and the slab C is provided. 4 are provided. The guide roll 1 and the jacket 4 described above may be the same as those of the conventional support cooling device.

A projecting piece 5 is provided on the rear side of the upper portion of the frame 2, and the projecting piece 5 is rotatably supported by a support bracket 7 via a pin 6 (see FIG. 2). See section view). Further, a projecting piece 8 is also provided below the frame 2, and a rod 10 of a hydraulic cylinder 9 serving as a biasing means is connected by a pin 11. In FIG. 1, 12 is a bracket that rotatably supports the hydraulic cylinder 9, and 13 is a pin. In the apparatus shown in FIG. 1, the support bracket 7 and the hydraulic cylinder 9 are provided only on the frame 2 on one side, but the path center of the slab C is directed straight downward so that no bending force is applied to the slab. Therefore, it is desirable that the support bracket 7 and the hydraulic cylinder 9 are provided symmetrically in a left-right pair.

When performing continuous casting using the support cooling device D configured as described above, the biasing force of the hydraulic cylinder 9 is set so as to correspond to the preset pressing force of the cast slab C. In order to constantly apply the same urging force to the hydraulic cylinder 9, for example, the pressure behind the piston 14 is maintained at a constant pressure by a relief valve or the reaction force applied to the roll is measured, and the hydraulic cylinder is based on the measured value. A method of adjusting the hydraulic pressure applied to the cylinder with a servo valve or the like may be adopted. In this way, when the cast slab C contracts due to cooling and the thickness w decreases, the frame 2 is pushed by the hydraulic cylinder 9, and the pin 6 is rotated in the direction of arrow A about the rotation center. You can Therefore, the guide roll 1 follows the decrease of the thickness w of the cast slab C, and always comes into contact with the surface of the cast slab C. On the contrary, when the thickness of the cast slab C is temporarily increased, the frame 2 rotates in the direction of the arrow B, and in this case as well, it can smoothly follow. Further, even when the slab C starts to meander, the hydraulic cylinder 9 follows the meandering and further operates to brake the meandering. Therefore, the contact between the guide roller 1 and the cast slab C is reliably maintained. In this way, since the cast slab C is always applied with an appropriate pressing force, breakout and bulging are effectively prevented. Further, by making sure that the guide roll 1 and the slab C are in contact with each other, the leakage of the cooling water can be minimized. Therefore, the amount of cooling water for obtaining a predetermined cooling action can be set accurately and the cooling capacity can be improved.

Next, a more preferable embodiment will be described with reference to FIGS. In the apparatus shown in FIG. 1, the first guide roll 1a immediately below the mold 51 is on the same line as the center of the pin 6, that is, the rotation center O2 of the frame 2. Therefore, even if the frame 2 moves in the directions of arrows A and B, the position of the first guide roll 1a hardly changes as shown in FIG. 3 (see an imaginary line P in FIG. 3). Therefore, the pressing force of the first guide roll 1a cannot be adjusted, the pressing force to the cast slab C becomes insufficient, and there is a problem that the cooling water blows up in the direction of the mold in a severe case. .. In order to deal with such a problem, in the apparatus shown in FIGS. 4 to 5, a rotation center moving mechanism 15 for moving the rotation center O2 of the frame 2 toward the cast slab C or away from the cast slab. Is incorporated.

The rotation center moving mechanism 15 is composed of an eccentric pin 16 used in place of the pin 6 and a second hydraulic cylinder 19 for rotating the eccentric pin 16. That is, the piston rod 20 of the second hydraulic cylinder 19 is connected by the pin 21 to the lever 18 fixed to the shaft end 17 of the eccentric pin 16. Both ends 22 and 23 of the eccentric pin 16 are supported by the support bracket 7, and the central eccentric part 24 is rotatably connected to the projecting piece 5 of the frame 2. As with the hydraulic cylinder 9, the second hydraulic cylinder 19 is also controlled to have a constant supply pressure so as to always provide a constant biasing force, or to be controlled based on the detected value. ..

In this rotation center moving mechanism 15, the protrusion 5 rotates in the normal state around the eccentric portion 24, and the same operation as that of the embodiment shown in FIG. 1 is performed. However, when the first guide roll 1a is about to separate from the cast slab C, the rod 20 of the second hydraulic cylinder 19 extends as shown in FIG. 6 to rotate the eccentric pin 16 about the rotation center M1 of its own axis. (Arrows E1 and E2) and the center M2 of the eccentric portion 24 is moved closer to or away from the slab C side. The amount of movement e is e · sin θ, where θ is the rotation angle of the pin. Therefore, the first guide roll 1a always comes into close contact with the slab C while maintaining a predetermined pressing force. As a result, the entire cast slab C can be reliably supported, and water leakage can be prevented more reliably. Furthermore, since the guide roll row moves following the solidification shrinkage and meandering of the slab, the roll alignment (the line drawn by the surface of the guide roll) is set to, for example, a plate (or an arc shape) before casting. This will reduce the time required to set the roll cavity and roll alignment.

Next, another embodiment of the rotation center moving mechanism will be described. In the rotation center moving mechanism 30 of FIG. 7, a horizontal guide groove 31 is provided in the support bracket 7, a slider 32 is slidably inserted therein, and the slider 32 is rotatably connected to the protrusion 5. Pin 33 is provided. The rod 20 of the second hydraulic cylinder 19 is connected to the slider 32 described above. The rotation center moving mechanism 30 supports the load in the slab withdrawal direction (casting direction) with the guide groove 31, and the contact between the first guide roller 1a and the slab C can be maintained by the expansion and contraction of the hydraulic cylinder 19. it can. Therefore, similarly to the rotation center moving mechanism 15, the slab supporting force and the sealability can be improved.

[0014]

[Effect of the device]

 According to the present invention, since the entire guide roll can always be reliably brought into contact with the slab with a predetermined pressing force, leakage of cooling water can be prevented to a minimum and a predetermined cooling capacity can be obtained. The amount of cooling water can be reliably maintained. In addition, the guide rolls securely support the slab, preventing bulging and breakout of the slab. Further, there is an advantage that the time for setting the roll cavity and the roll alignment is reduced. According to the second aspect of the present invention, since the slab support cooling device can be moved in the slab direction in addition to the rotation of the frame, adjustment which cannot be performed by the rotation of the frame, particularly the position of the first guide roll (pressing force) ) Can also be adjusted, so that the clearance between the first guide roll and the slab and the pressing force can be reliably adjusted.

[Brief description of drawings]

FIG. 1 is a schematic front view showing a slab support cooling device according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is an operation explanatory view of the embodiment shown in FIG.

FIG. 4 is a front view showing an embodiment of a rotation center moving mechanism according to the present invention.

5 is a sectional view taken along line VV of FIG.

FIG. 6 is an explanatory diagram showing an operation of the rotation center moving mechanism of FIGS.

FIG. 7 is a front view showing another embodiment of the rotation center moving mechanism according to the present invention.

8 is a perspective view showing an example of a support cooling device of Conventional Example I. FIG.

FIG. 9 is a front view showing an example of a support cooling device of Conventional Example II.

[Explanation of symbols]

1 guide roll 2 frame
4 Jacket 6 pin 7 Support bracket
9 Hydraulic cylinder 15 Rotation center moving mechanism 16 Eccentric pin
19 Second hydraulic cylinder 30 Rotation center moving mechanism

Claims (3)

[Scope of utility model registration request] 1. A slab support cooling device for cooling while pressing and supporting each surface of a slab having a rectangular cross section coming out of a mold of a continuous casting machine, the slab supporting cooling device being arranged along a moving direction of the slab. A plurality of guide rolls, a frame that rotatably supports the guide rolls, a jacket that forms a passage for cooling water between two adjacent guide rolls and the surface of the slab, and the frame near the upper end. A slab support cooling device in a continuous casting machine, comprising: a support bracket rotatably supported by a slab and a urging means for urging a lower portion of the frame toward the slab. 2. The slab support cooling device according to claim 1, further comprising a rotation center moving mechanism for moving the rotation center of the frame so as to move toward or away from the slab. . 3. The slab support cooling device according to claim 2, wherein the rotation center moving mechanism comprises an eccentric pin and means for rotationally driving the eccentric pin.