JP3991138B2 - Coarse reduction device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rough reduction device that significantly reduces a slab plate thickness.
[0002]
[Prior art]
High-pressure presses have been developed that reduce the slab thickness to about half in one pass. FIG. 9 is a view showing a slab shape when the slab 1 is subjected to high pressure under such a high pressure press or mill. (A) shows the state before the slab 1 is crushed by the mold or the roll 21, and (B) shows the shape of the slab 1 when the thickness is crushed almost by half. Since the volume itself is almost the same amount even if it is reduced, the remaining half volume moves in the length direction and the width direction of the slab 1 when the thickness is about half. The volume moved in the width direction constitutes bulge portions 22 at both ends as shown in the figure.
[0003]
[Problems to be solved by the invention]
FIG. 10 shows an edge crack 23 that occurs in the bulge portion 22. Since the bulge portion 22 is easily tensioned on the surface and cooled, the edge crack 23 is likely to occur. FIG. 11 shows a state in which the high-pressure slab 1 is rolled by a rolling mill provided downstream. (A) shows a state immediately before rolling with the roll 24, and (B) shows seam scratches 26 generated on the surface of the rolled material. The top portion 25 of the bulge portion 22 is easily cooled, and edge cracks are likely to occur as shown in FIG. 10. However, even if the cracks are not reached, the top portions 25 are in a state of being easily broken. A streak occurs. This is called seam scratch. Such edge cracks and seam scratches are undesirable because they may remain in the product. In addition, as shown in FIG. 1, when a high pressure is applied with a mold 4 having an inclined surface 4 b in the length direction of the slab 1, sliding between the slab 1 and the mold is easy and sufficient reduction may not be possible.
[0004]
The present invention has been made in view of the above-described problems, and an object thereof is to adjust the width of a slab and prevent the occurrence of edge cracks and seam scratches. Another object is to prevent slippage between the press mold and the slab.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, according to the first aspect of the present invention, an edger for pressing the slab in the width direction is provided on the entry side of the reduction press.
[0006]
When the slab is reduced in the slab width direction by an edger, the gap end that causes cracks is crushed inside the slab width end portion, and cracks and scratches are less likely to occur even if the slab is reduced in the thickness direction by a reduction press. Thereby, in addition to the adjustment of the slab width, the occurrence of cracks and scratches can be prevented. Further, the rotation of the width reduction roll of the edger has the effect of pushing the slab into the reduction press. Similarly, the rotation of the width reduction roll also has the effect of preventing slippage between the mold having an inclined surface in the slab length direction and the slab.
[0007]
According to a second aspect of the present invention, the edger includes a cylindrical roll that presses while rotating the slab width end.
[0008]
Since the slab width end face is crushed by the cylindrical roll to crush gaps and the like that are present inside and cause cracking, cracks and scratches are less likely to occur even if the slab width is reduced from the thickness direction by a rolling press. In this case, the swell is generated at the width end portion, but since it is compressed by the width reduction, no crack is generated by the reduction in the thickness direction.
[0009]
According to a third aspect of the present invention, the central portion of the cylindrical roll is provided with a projection having a mountain shape on the roll circumference.
[0010]
By providing a recess by a roll protrusion at the center of the slab width end surface, when the bulge generated at both ends is subsequently reduced in the thickness direction by a reduction press, the volume is reduced, and the thickness reduction can be performed smoothly.
[0011]
According to a fourth aspect of the present invention, the edger includes a pincushion roll that presses while rotating the slab width end, and the pincushion roll opens outwardly connected to the central cylindrical portion and both ends of the central cylindrical portion. And a tapered portion and an outer cylindrical portion connected to the outside of the tapered portion.
[0012]
By reducing the width of the pincushion roll, the end surface of the slab width can be formed into a shape having a vertical surface and inclined surfaces above and below the vertical surface. Thereby, when it is squeezed from the thickness direction by a squeezing press after that, it has a shape in which a large swell is unlikely to occur. As a result, it is possible to prevent the occurrence of edge cracks at the time of thickness reduction and seam scratches during subsequent rolling.
[0013]
In the invention of claim 5, the central cylindrical portion of the pincushion roll is provided with a projection having a mountain shape on the circumference of the central cylindrical portion.
[0014]
By providing a recess by a roll protrusion at the center of the slab width end surface, when the bulge generated at both ends is subsequently reduced in the thickness direction by a reduction press, the volume is reduced, and the thickness reduction can be performed smoothly.
[0015]
In the invention of claim 6, in the combination of the reduction press and the edger, the roll speed of the edger is a slab conveyance speed at the time of non-reduction, and a speed obtained by subtracting the reverse speed due to reduction from the slab conveyance speed at the time of reduction. And
[0016]
The reduction press is a running press that conveys the slab even during reduction. Although the slab extends in the slab length direction when the slab is reduced, the extension speed in the direction opposite to the slab conveyance direction (edger direction) of the extension is called the reverse speed. The roll speed of the edger is adjusted to the slab conveyance speed when not being reduced, and when reduced, the width reduction and thickness reduction can be performed simultaneously by subtracting the reverse speed due to the reduction from the slab conveyance speed at the time of reduction. it can.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a configuration of a rough reduction device according to a first embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along line AA of FIG. The rough reduction device is composed of a high pressure press 2 which reduces the plate thickness by 50 mm or more under a high pressure in the thickness direction arranged along the flow direction of the slab 1, and an edger 3 arranged on the entry side. The high pressure lower press 2 includes a mold 4 having a parallel surface 4a parallel to the upper and lower surfaces of the slab 1 and an inclined surface 4b inclined to the entry side, a rolling mechanism 5 for periodically rolling down the mold 4 in the vertical direction, It consists of a reciprocating mechanism 6 that reciprocates the mold 4 and the reduction mechanism 5 in the flow direction of the slab 1. Although a crank mechanism is schematically shown as the reduction mechanism 5, other mechanisms such as a hydraulic cylinder may be used. Although a hydraulic cylinder is schematically shown as the reciprocating mechanism, other mechanisms such as a crank mechanism may be used. The edger 3 includes a pair of cylindrical rolls 7 that rotate while pressing the slab 1 in the width direction. The cylindrical roll 7 is rotated as indicated by an arrow by a rotary drive device (not shown) to press the slab 1 in the width direction and send it out in the slab flow direction. The pinch roll 8 conveys the slab 1 in the slab flow direction.
[0018]
Next, the operation will be described. When not pressed, the mold 4 is separated from the slab 1, the slab 1 is conveyed by a pinch roll 8 at a predetermined speed in the slab flow direction, and the edger 3 rotates the cylindrical roll 7 in accordance with the conveying speed to remove the slab 1. Send it out. During the reduction, the reciprocating mechanism 6 feeds the mold 4 at the conveyance speed of the slab 1 and conveys the slab 1 even during the reduction. The volume that has become thinner due to the reduction flows in the slab flow direction, in the opposite direction and in the width direction, and the speed that flows in the opposite direction to the inner slab flow direction is called reverse speed. The cylindrical roll 7 sends out the slab 1 at a speed obtained by subtracting the reverse speed from the slab conveying speed.
[0019]
Since both width ends of the slab 1 are rolled down in the width direction by the cylindrical roll 7, the slab width can be set to a predetermined dimension. Further, as shown in FIG. 2, both width ends of the slab 1 produce a bulging portion 9, which is different from the bulging portion 22 described in FIG. 9, and is a gap that causes cracks existing inside the material due to the reduction. Etc. are crushed (referred to as a forging effect), so cracks and flaws do not occur. If there is an inclined surface 4 b on the entrance side of the mold 4, slippage is likely to occur between the slab 1 and the mold 4 at the time of rolling, but slippage is prevented by the slab feeding action of the edger 3. Further, the slab 1 can be fed into the press 2 under high pressure by this slab feeding action.
[0020]
Next, a second embodiment will be described. FIG. 3 shows a configuration of the second embodiment, and FIG. 4 shows a BB cross section of FIG. This embodiment is the same as the first embodiment except that a cylindrical roll 10 with protrusions is provided in which a protrusion 11 having a mountain-like cross section is provided circumferentially at the center of the cylindrical roll 7 in FIG. is there. When concave portions 12 are formed on both width end faces of the slab 1 by the projections 11, when the raised portion 9 is squeezed by the high pressure lower press 2, the material flows into the concave portions 12, and good pressing can be performed.
[0021]
Next, a third embodiment will be described. FIG. 5 shows the configuration of the third embodiment, and FIG. 6 shows a CC cross section of FIG. This embodiment is the same as the first embodiment except that the cylindrical roll 7 of FIG. The pincushion roll 13 is composed of a central cylindrical portion 13a, a tapered portion 13b that is open to the outside connected to both ends of the central cylindrical portion 13a, and an outer cylindrical portion 13c that is connected to the outside of the tapered portion 13b. ing. Both width end surfaces of the slab 1 become a vertical surface 14a by the central cylindrical portion 13a, become an inclined surface 14b by the tapered portion 13b, and the raised portion 14c is smaller than those in the first and second embodiments. Generation of cracks can be prevented by the inclined surface 14b.
[0022]
Next, a fourth embodiment will be described. FIG. 7 shows a configuration of the sixth embodiment, and FIG. 8 shows a DD cross section of FIG. This embodiment is different from the third embodiment in that the center-cylindrical portion 13a of the pincushion roll 13 in FIG. 5 is provided with a pincushion roll 15 with a protrusion having a mountain-like protrusion 16 on the circumference. Are the same. Since the recesses 17 are generated on the both end faces of the slab 1 by the projections 16, the material flows into the recesses 17 when the swelled portion 14 c is reduced by the high-pressure press 2, so that good pressing can be performed.
[0023]
Although the case where the high pressure press 2 was arrange | positioned after the edger 3 was demonstrated in the above 1st-4th embodiment, even if it uses a high pressure mill instead of the high pressure press 2, the same effect is acquired. The high-pressure mill is a one-stage mill that reduces by 50 mm or more.
[0024]
【The invention's effect】
As is apparent from the above description, the present invention provides the following effects by providing the edger on the entry side of the high pressure press or high pressure mill.
(1) Edge cracking can be reliably prevented as compared with the case of a high-pressure press or a high-pressure mill alone.
(2) The width of the slab can be adjusted.
(3) The effect of pushing the slab into the press or mill occurs.
(4) Sliding between the press die or mill roll and the slab can be prevented.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of a first exemplary embodiment of the present invention.
FIG. 2 is a cross-sectional view taken along the line AA of FIG.
FIG. 3 is a diagram showing a configuration of a second exemplary embodiment of the present invention.
4 is a cross-sectional view taken along the line BB in FIG.
FIG. 5 is a diagram showing a configuration of a third exemplary embodiment of the present invention.
6 is a cross-sectional view taken along the line CC of FIG.
FIG. 7 is a diagram showing a configuration of a fourth exemplary embodiment of the present invention.
8 is a cross-sectional view taken along the line DD of FIG.
FIG. 9 is a diagram showing that bulging occurs at the width end due to high pressure of the slab.
FIG. 10 is a diagram showing a crack generated in a bulge portion.
FIG. 11 is a diagram for explaining the occurrence of seam flaws.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Slab 2 Press under high pressure 3 Edger 4 Die 4a Parallel surface 4b Inclined surface 5 Reduction mechanism 6 Reciprocation mechanism 7 Cylindrical roll 8 Pinch roll 9 Swelling part 10 Cylindrical rolls 11 and 16 with protrusions 12 and 17 Recess 13 Pincushion roll 13a Central cylindrical portion 13b Tapered portion 13c Outer cylindrical portion 14a Vertical surface 14b Inclined surface 14c Swelling portion 15 Protruded pincushion roll 21 Mold or roll 22 Swelling portion 23 Edge crack 24 Roll 25 Top portion 26 Seam scratch

Claims (6)

A rough reduction device characterized in that an edger for pressing the slab in the width direction is provided on the entry side of the reduction press. 2. The coarse reduction device according to claim 1, wherein the edger includes a cylindrical roll that presses while rotating a slab width end. The rough reduction device according to claim 2, wherein a protrusion having a mountain shape in cross section is provided on the circumference of the roll at a central portion of the cylindrical roll. The edger includes a pincushion roll that presses while rotating the slab width end, and the pincushion roll has a central cylindrical part, an outer tapered part connected to both ends of the central cylindrical part, and the tapered part. 2. The coarse reduction device according to claim 1, wherein the rough reduction device is composed of an outer cylindrical portion connected to the outer surface of the outer cylindrical portion. 5. The coarse reduction device according to claim 4, wherein a projection having a mountain-shaped cross section is provided on the circumference of the central cylindrical portion of the central cylindrical portion of the pincushion roll. In the combination of the reduction press and the edger, the roll speed of the edger is a slab conveyance speed when not being reduced, and is a speed obtained by subtracting the reverse speed due to reduction from the slab conveyance speed at the time of reduction. The rough reduction device according to claim 1.

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