JPH0337762Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The technical content described in this specification regarding the anvil of a press machine that continuously rolls down hot slabs (hereinafter referred to as slabs) is to To improve an anvil that can advantageously suppress twisting, bending, buckling, etc. that occur in the anvil.

Generally, slabs whose width is reduced using a continuous hot rolling mill are often manufactured by continuous casting, but the width of this cast slab is limited and it is necessary to adjust the slab width in order to obtain the desired product width. Conventionally, an edge rolling mill was used to adjust the slab width, but a new continuous width rolling technique using a press has been developed (Japanese Patent Laid-Open No. 101201/1983).

(Prior Art) Conventionally, as a roll shape of an edger rolling mill for width rolling of slabs, there is a caliber-shaped roll disclosed in Japanese Patent Application Laid-Open No. 138963/1983. This shape is used to prevent the slab from rising and to reduce the increase in thickness near the side edges of the slab (so-called dogbone deformation) that occurs during width rolling. The purpose of reducing dogbone deformation is to suppress the width expansion in the subsequent horizontal rolling and increase the width reduction efficiency of the edging rolling. Various ideas have been devised regarding the shape of the roll, since this is one of the causes of scratches on the lower surface at a high relative speed.

On the other hand, in the case of continuous width reduction by pressing a slab, the width reduction efficiency is very excellent, so there is little need to adopt a caliber shape for the anvil whose main purpose is to improve the efficiency. Conversely, when pressing is performed with a caliber-shaped anvil, scratches occur on the top and bottom surfaces of the thickened slab, and iron oxide (scale) on the slab surface accumulates inside the caliber, and this scale is pressed against the slab, causing scratches. becomes. Therefore, although it is not possible to adopt a caliber shape as in the above-mentioned edge rolling for the anvil of a continuous press, it is necessary to take measures to prevent twisting, bending, buckling, etc. of the slab that occurs during pressing.

(Problems to be Solved by the Invention) The problem is to prevent twisting, bending, and buckling (hereinafter collectively referred to as twisting) of the slab that occurs during pressing using a method that is particularly compatible with the press equipment.

(Means for solving the problem) This invention forms a pair across the hot slab in the width direction, and includes parallel parts along the conveyance direction of the hot slab;
An anvil for a continuous width reduction press having an inlet side in the conveying direction, or an inclined part with a mutual interval increasing toward the inlet side and an outlet side, the anvil having at least the inclined part on the input side along the conveying direction. The depression includes a slope area extending from the contact point of the slope part and the parallel part toward the slope part and extending for 1/2 the length of the slope part, and a slope area parallel to the slope part surface from the contact point to the slope part area. The maximum radius of curvature R of the contour curve of the bottom of the recess in the cross section perpendicular to the conveying direction is determined by the maximum radius of curvature R of the hot slab to be width-reduced. 0.7W for the width W of the smallest one
This is an anvil for a hot slab continuous width reduction press machine characterized by <RW.

Now, to explain about the anvil 2 of the press machine shown in Fig. 1, this anvil 2 has an inclined part 3 whose mutual spacing increases toward the entry side in the slab conveyance direction (indicated by an arrow in the figure), and a sloped part 3 which also extends along the conveyance direction. The parallel parts 4 are respectively provided.

Further, a depression 5 is formed in a portion of the anvil 2 that will be in contact with the slab 1 along the conveyance direction of the slab.
This depression 5 has the maximum radius of curvature R of the bottom contour curve in a cross section perpendicular to the conveyance direction.

Note that the bottom contour curve of the depression 5 may be a circle, a part of an ellipse, etc., but in the following explanation, it is assumed that the bottom contour curve of the depression 5 is constituted by a circular arc with a constant curvature. An example is shown in Figure 2.

In Fig. 2, the bottom contour curve of the depression 5 has a radius R
It is an arc of a circle, and is less than or equal to the width W of the smallest hot slab among the hot slabs to be width-reduced by a press device equipped with an anvil 2. If the radius R exceeds W, the effect of preventing twisting cannot be exhibited when reducing the width of the minimum slab. On the other hand, the minimum value of the radius R is approximately 70% of the width W of the minimum width slab. That is, by setting 0.7W<RW, when the slab is about to twist, a self-correcting ability is activated in which the corners in the twisting direction can be rolled down more, and the twisting of the slab can be naturally suppressed.

Further, FIG. 3 shows the state of the slab during continuous width reduction. As can be seen from the initial contact area e and final contact area E shown in the figure, the reduction of the slab 1 is mainly due to the sloped part 3 on the entry side, so the depression 4 is mainly formed in this sloped part 3. That is, as shown in FIG. 4, the recess 5 is formed by a length (≒L) from the rear half of the entrance side slope part 3 where the slab is particularly prone to twisting, that is, the contact point Z between the slope part 3 and the parallel part 4. /2) in the slope area A and similarly in the parallel area B from the contact point Z until the bottom of the depression 5 extending parallel to the surface of the slope part 3 in the slope area A reaches the surface of the parallel part 4. .

Note that the depression 5 is as shown by the broken line in FIG.
Since the width of the slab is finally reduced in the parallel portion 4, it is not preferable to form a recess that is too long, and therefore the parallel portion region B is preferably shortened.

Further, FIG. 5 shows an anvil 2A having a sloped part 6 on the exit side for preforming the rear end of the slab, but this anvil 2A also has a recess 5 in the sloped part 3 on the entry side, similar to the above-mentioned anvil 2. In addition, if it is necessary to prevent kinking during preforming of the rear end of the slab (normally, kinking during preforming of the rear end of the slab is small), a depression 5 is also formed in the inclined portion 6 on the exit side.

(Function) First, the causes of twisting of the slab during width reduction are uneven shape of the side end surface of the slab material, poor levelness when conveying the slab between the anvils,
Due to uneven temperature in the width direction of the slab, and the shape of the dog bone that occurs on the side of the slab differs on the left and right sides of the side due to uneven temperature, the horizontality of the slab when it comes into contact with the conveyance table on the exit side is This includes things like not being able to maintain it.

Assume that due to these reasons, the positional relationship between the rolled surface of the anvil and the end surface of the slab becomes as shown in FIG. The anvil shown in the figure does not have a conventional recess.

First, let's talk about the case where the contact between the slab 1 and the anvil 7 shown in Fig. 6a is in the early stages.The meat of the pressed part of the slab 1 needs to escape to the outside, but the method of escape is shown in the figure. As such, more escapes to the bottom and less escapes to the top.

Even when the reduction progresses further to reach the state shown in FIG. 6b, the tendency is the same, and the amount of meat escaping to the lower side is greater. At this time, the slab 1 receives a force in the direction opposite to the direction in which the meat escapes (indicated by the arrow in the figure), so that the twisting increases.

In order to prevent twisting due to the relationship between the slab and the anvil described above, it is necessary to increase the amount of reduction applied to the upper side of the slab in FIG. 6. Especially if it starts to twist, the ideal shape of the anvil is such that it can increase the amount of reduction applied to the corner on the twisted side depending on the amount of twist.

Therefore, it is effective to form a recess in the shape shown in FIG. 2, for example, in the anvil. As described above, by making the depression satisfy 0.7W<RW, when the slab tries to twist, the corners in the twisting direction can be reduced by a large amount, giving the slab self-correcting ability.

(Effects of the invention) This invention naturally prevents kinks that occur in the slab during continuous width reduction by pressing the slab, and allows pressing to be carried out smoothly and with high precision.

[Brief explanation of the drawing]

Figure 1 is a perspective view of the anvil, Figure 2 is an explanatory diagram of the depression, Figure 3 is a diagram showing press reduction, Figure 4 is a plan view of the anvil, Figure 5 is a plan view of the anvil, Figure 6 a. ,b
is a diagram showing conventional press reduction. 1... Slab, 2... Anvil, 3, 6... Inclined part, 4... Parallel part, 5... Recess.

Claims (1)

[Claims for Utility Model Registration] A pair is formed with a hot slab sandwiched in the width direction, and a parallel part along the conveying direction of the hot slab and a mutually opposite part toward the entrance side or the input side and the exit side in the conveyance direction. An anvil for a continuous width reduction press having sloped portions with increasing intervals, at least the sloped portion on the input side is provided with a recess along the conveyance direction, and the recess is formed between the sloped portion and the parallel portion. 1/2 of the slope length from the contact point to the slope part
and a parallel part area extending from the contact point to the parallel part surface until the bottom of the depression extending parallel to the slope surface reaches the parallel part surface; The maximum radius of curvature R of the bottom contour curve of the depression is 0.7W relative to the width W of the smallest hot slab to be subjected to width reduction.
<An anvil for a hot slab continuous width reduction press machine characterized by being RW.