JPH0726027Y2 - Thickness reduction press die - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a die for a thickness reduction press.

[Prior Art] A conventional thickness reduction press is a flat mold 10 having a horizontal portion 12 on the entire pressure lower surface as shown in FIGS. 7 and 8, or
As shown in FIG. 9, a continuous casting material is provided between the upper and lower metal molds 10 and 11 by arranging the taper metal molds 11 in which the taper parts 13 having a required angle are formed on the entrance side of the horizontal part 12 as shown in FIG. Plated 14 and continuous cast material 1
4, or by moving the molds 10 and 11 intermittently in the longitudinal direction 15 and moving the molds 10 and 11 closer to and away from each other,
The thickness of the continuous cast material 14 is reduced.

Since such a thickness reduction press can apply a large press load to the continuous casting material 14, it has an advantage that a large reduction amount can be secured as compared with a rolling mill using a roll.

[Problems to be Solved by the Invention] However, the conventional flat mold 10 or taper mold 11 described above is used.
The following problems have been encountered in the thickness reduction press using the above.

That is, in the rolling machine using the roll, while the reduction amount is small, it is possible to apply a continuous rolling load to the continuous casting material 14 in the longitudinal direction 15, so that the continuous casting material 14 is uniform in the longitudinal direction 15. The thickness can be reduced.

However, in the thickness reduction press, generally, as shown by the alternate long and short dash line in FIG. 9, the horizontal portion 12 of the molds 10 and 11 applies the press load 16 applied to the continuous cast material 14 by one press to the continuous cast material. When viewed in the longitudinal direction 15 of 14, the load distribution is large directly below the center of the mold and small on both sides, so the center of the mold has a sufficient effect of reducing the volatility, but the effect is smaller on both sides. There was a problem of becoming.

Moreover, since the dies 10, 11 or the continuous casting material 14 are intermittently fed, there is a problem that the above distribution occurs periodically (note that the dies 10, 11 are shown in FIG. 9). Shows the case of feeding the same amount as the dimension in the longitudinal direction 15,
The feed amount may be made smaller so that the reduction ranges partially overlap. In this case, the periodicity of the above distribution becomes more complicated, but it is still periodic).

Thus, in the thickness reduction press, the continuous cast material 14 is
Since it was not possible to uniformly reduce the thickness of the continuous casting material 14, it is necessary to uniformly and sufficiently crush the minute voids called porosity generated in the central portion inside the continuous casting material 14 in the longitudinal direction 15 in the casting process. I couldn't.

In view of the above situation, the present invention aims to provide a die for a thickness reduction press capable of uniformly reducing the thickness of a continuous casting material in the longitudinal direction and effectively crushing porosity. It is what

[Means for Solving the Problems] The present invention has a taper portion on the pressure face which approaches the thickness center 2 as it goes to the exit side of the continuous casting material 1 in the longitudinal direction 15 and whose angle to the longitudinal direction 15 is approximately 20 degrees or less. A thickness reducing press characterized in that three and five and horizontal portions four and six adjacent to the taper portions three and five are hung from the inlet side to the outlet side of the continuous casting material 1 to form two stages. It depends on the mold.

[Operation] Therefore, in the present invention, when the thickness of the continuous casting material 1 is vertically lowered by arranging the dies of the thickness reduction press vertically, the continuous casting material 1 is reduced.
Is continuously reduced in thickness by the taper portion 3 of the first step on the entry side, is crushed to a uniform thickness by the horizontal portion 4 of the first step in the next step, and is further crushed by the second step in the next step. The thickness is continuously reduced by the taper portion 5 of the and the thickness is finally crushed by the horizontal portion 6 of the second stage so that the porosity generated inside the continuous cast material 1 is effectively and uniformly crimped. It

The same portion of the continuous cast material 1 is pressed once or a plurality of times by the respective parts 3, 4, 5 and 6 of the mold according to the feed amount of the continuous cast material 1.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings.

1 and 2 are explanatory views of an embodiment of the present invention.

Connected to the pressure surface in order from the inlet side to the outlet side of the continuous casting material 1 to the taper portion 3 whose inclination angle θ ₁ toward the thickness center 2 of the continuous casting material ₁ is 20 degrees or less, and the taper portion 3. The horizontal portion 4 and the horizontal portion 4 connected to the horizontal portion 4 toward the thickness center 2 of the continuous cast material 1.
A taper portion 5 having an inclination angle θ ₂ of 20 degrees or less, and a horizontal portion connected to the taper portion 5 and having a step height h between the horizontal portion 4 and half or less of a thickness reduction amount of the entire continuous cast material 1 And 6 to form the two-stage mold 7.

Since the angles of the tapered portions 3 and 5 are restricted by the step between the horizontal portions 4 and 6 and the dimension of the two-step mold 7 in the longitudinal direction 15,
Practically, it is preferably 10 degrees or more.

The two-stage die 7 is attached to a thickness reduction press (not shown) so as to be able to move closer to and away from the vertical direction, and the upper and lower two-stage dies 7 can reduce the thickness of the continuous casting material 1.

Next, the operation will be described.

When the continuous cast material 1 or the two-stage mold 7 is intermittently fed to the downstream side, the upper and lower two-stage molds 7 are moved closer to and away from each other to reduce the thickness of the continuous cast material 1, the continuous cast material 1 The same portion of the two-stage mold 7 passes through the taper portion 3, the horizontal portion 4, the taper portion 5 and the horizontal portion 6 formed on the pressure lower surface of the two-stage die 7, and each portion 3 The thickness is reduced once or a plurality of times with 4, 5, 6, and the horizontal portions 4, 6 at two places are subjected to uniform crushing twice.

As described above, by performing uniform crushing in two steps, minute voids called porosity generated inside the continuous casting material 1 in the continuous casting process can be uniformly and effectively pressed in the longitudinal direction 15. .

In addition, before performing uniform crushing on the horizontal parts 4 and 6,
By continuously reducing the thickness of the continuous cast material 1, it is possible to reduce the amount of thickness reduction in the horizontal portions 4 and 6, so that the harmful effects such as cracking of the continuous cast material 1 are prevented. In addition, the effect of uniform crushing in the horizontal portions 4 and 6 can be promoted.

The dimensional relationship between the parts 3, 4, 5 and 6 will be described. Since the continuous casting material 1 is extended in the longitudinal direction 15 by the thickness reduction, the parts 3, 4, 5 and 6 are reduced only once. So that
Longitudinal direction 15 of the contact portion of the taper portion 3 with the continuous cast material 1
Is required to be equal to the feed amount of the continuous cast material 1, and the dimension of the downstream side portions 4, 5 and 6 in the longitudinal direction 15 is to be gradually increased according to the extension of the continuous cast material 1. .

However, in the continuous cast material 1, the same parts are the parts 3, 4, 5 and 6 of the mold 7.
Since it is not necessary to reduce the pressure once,
The dimensional relationship of the respective parts 3, 4, 5, 6 in the longitudinal direction 15 does not have to be as described above.

Next, a model experiment conducted to investigate the effect of the present invention will be described.

FIG. 3 is an explanatory diagram of the slab 8 used in the model experiment.

The slab 8 is made of SS steel or S45C steel and has a width of 200 m.
It has a length of m, a length of 600 mm, and a thickness of 50 mm, and is heated to almost the same temperature as the actual continuous cast material 1.

Then, in order to experimentally reproduce the porosity, a plurality of 3 [phi] drill holes 9 extending in the width direction are bored in the longitudinal direction 15 at intervals of 10 mm at the center position of the thickness.

In addition, the porosity is actually a microscopic size of about 500 μ or less, but since it is difficult to reproduce such a micro perforation hole 9, in the experiment, the minimum size that can be drilled is 3φ. Set.

In the above model experiment, the conventional flat mold 10 and the taper mold 11 were prepared, and it was decided to carry out a comparative experiment with the two-stage mold 7.

Further, in the case of any of the molds 7, 10 and 11, the rolling amount is kept constant and the slab 8 is pressed in the thickness direction while the molds 7, 10 and 11 are fed, and the feed amount of the mold is kept constant. If you do
The vertical size of each drill hole 9 after deformation, that is, the hole height b after deformation (see FIG. 4) was measured.

In FIG. 5, the horizontal axis represents the distance in the longitudinal direction of the slab 8 and the vertical axis represents the hole height b after deformation, and based on the results of the model experiment using the heated slab 8, the long side of the slab 8 FIG. 6 is a diagram that summarizes in an easy-to-understand manner how the drill holes 9 formed at each position were deformed.

In the figure, the two-stage mold 7 is shown by a line (a), the taper mold 11 is shown by a line (b), and the flat mold 10 is shown by a line (c).

Here, the longitudinal distance of the slab 8 is a distance in the long side direction with one end of the long side of the slab as a reference point, and corresponds to the distance in the longitudinal direction 15 of the continuous cast material 1 in an actual machine.

From this diagram, when the two-stage mold 7 is used, the drill hole 9 is not completely crushed, but the post-deformation hole height b is the smallest compared to the other cases. Since the drill hole 9 is much larger than the actual porosity, if the post-deformation hole height b is such a low value, it can be evaluated that the porosity can be sufficiently crushed at the actual machine level without any problem. .

Also, as shown in FIG.
Has a load distribution in the press load 16 applied to the continuous cast material 14, and the continuous cast material 1 or the mold 10 is intermittently sent in the longitudinal direction 15. Therefore, depending on the thickness reduction amount (or the thickness reduction). ,
There is a problem that periodic fluctuations in the longitudinal direction 15 occur in the amount of extension of each part in the longitudinal direction 15 (therefore, periodic fluctuations do not occur in the width direction.
Since it varies depending on the size of the longitudinal direction 15 of 7, 10, 11 and the feed amount, etc., it cannot be stated unconditionally, but the occurrence of periodicity remains the same).

The periodical variation of the amount of reduction in the longitudinal direction 15, which is a problem peculiar to the thickness reduction press, was examined based on the results of FIG.

Then, in any of the two-step mold 7, the taper mold 11, and the flat mold 10, the post-deformation hole height b of the drill hole 9 is different depending on the location, and the post-deformation hole height b is , The slab 8 in the longitudinal direction 15 was periodically changed.

However, the difference between the highest point and the lowest point of the post-deformation hole height b in a certain cycle, that is, the variation width, is used as an index of the post-deformation hole height longitudinal variation amount Δb (see FIG. 5). Mold 7,
Comparing each case of taper mold 11 and flat mold 10,
It was confirmed that the post-deformation hole height longitudinal variation amount Δb was the smallest in the two-step mold 7, and the two-step mold 7 deformed the drill hole 9 most uniformly.

In this way, the two-step mold 7 was able to deform the drill hole 9 most uniformly because the two-step mold 7 has two horizontal portions 4 and 6,
It is considered that as a result of performing the uniform crushing of the continuous cast material 1 in two steps, the above-mentioned cycle became fine and complicated.

Since the drill hole 9 is much larger than the actual porosity, if the post-deformation hole height longitudinal variation Δb is such a small value, at the actual machine level,
It can be evaluated that the porosity can be crushed sufficiently uniformly without any problem.

Furthermore, as described above, the cyclic fluctuation of the thickness reduction amount peculiar to the press changes depending on the size of the mold and the feed amount of the mold or the continuous casting material, and it will be briefly described what the cycle is. However, as the feed amount is made smaller, the cycle becomes more complicated and finer, so that a more uniform state is approached.

Therefore, when the feed amount of the continuous casting material 1 is changed, how the porosity crushing effect in the width direction of the continuous casting material 1 changes is investigated by another experiment similar to the above, and the result is shown in FIG. It is summarized in a) to (c).

6A to 6C, the horizontal axis represents the distance from the width end of the slab 8 and the vertical axis represents the post-deformation hole height longitudinal variation Δb.

And FIG. 6 (a) shows that when the die feed amount is 20 mm,
FIG. 6 (b) shows the case where the die feed amount is 30 mm, and FIG. 6 (c) shows the case where the die feed amount is 40 mm.

The material of the slab 8 is S45C steel in FIG. 6 (a) and SS steel in FIGS. 6 (b) and (c).

Furthermore, the two-stage mold 7 is shown by a line (a), the taper mold 11 is shown by a line (b), and the flat mold 10 is shown by a line (c).

From these three diagrams, the two-stage mold 7 is
As compared with the taper mold 11 and the flat mold 10, the post-deformation hole height variation Δb in the longitudinal direction is the smallest at any position in the width direction, and the drill hole 9 is the most uniform in the width direction of the slab 8.
You can see that is transformed.

Since the drill hole 9 is much larger than the actual porosity, if a value as small as this is obtained, the porosity can be uniformly crushed in the width direction without any problem at the actual machine level. It can be evaluated as something.

In FIG. 6, in any of the molds 7, 10 and 11, the post-deformation hole height longitudinal variation Δb at the width end is larger than that in the central portion. It occurs because the width end of the slab 8 cannot be sufficiently restrained,
Generally, since the continuous cast material 1 is solidified from the peripheral portion toward the central portion in the continuous casting process, porosity is concentrated only in the central portion of the continuous cast material 1, so that there is no problem at the actual machine level. .

Further, as shown in FIG. 6 (c), it can be seen that the deformation effect of the drill hole 9 is sufficiently large in the two-step mold 7 even when the mold feed amount is increased.

Therefore, if the same deformation effect is obtained, the two-step mold 7 is a taper mold.
Compared with the case of 11 and the flat mold 10, it is possible to increase the amount feeding of the continuous casting material 1 and improve the production efficiency.

Summarizing all the model experiments above, the two-stage mold 7 is
Compared with the conventional flat mold 10 and taper mold 11, both the longitudinal direction 15 and the width direction of the slab 8 have a large deformation ability for the drill hole 9, and the drill hole 9 is uniformly deformed in the longitudinal direction 15. Therefore, it was possible to evaluate that the porosity generated in the continuous cast material 1 could be uniformly and sufficiently crushed in the longitudinal direction 15 even at the level of the actual machine.

The present invention is not limited to the above embodiment,
It goes without saying that various changes can be made without departing from the scope of the present invention.

[Effect of the Invention] As described above, according to the die for the thickness reduction press of the present invention, the porosity generated in the continuous cast material 1 is made uniform in the longitudinal direction and the width direction by the two-stage horizontal portions 4 and 6. In addition, it can be crushed effectively, and the tapered surface 3, 5 with an angle of approximately 20 degrees or less makes the shape of the pressure surface relatively smooth, and there is no abrupt shape change part on the pressure surface. As the thickness reduction proceeds due to the thickness reduction, the thickness of the continuous cast material 1 after pressing is less likely to change, and the volume of the continuous cast material 1 that is pressed down once is constant. If it does not occur, the width fluctuation does not occur, it is possible to obtain a rolled state close to that when continuously rolling using a rolling roll, and it becomes easy to correct the continuous cast material 1 in the subsequent step, Also, since the pressure surface is relatively smooth, the continuous cast material 1 It is not sharply rolled down and cracks are not generated, and since the rolling surface is relatively smooth, there is no sharp angle in the rolling down portion of the continuous cast material 1. It is possible to prevent folds and the like when it is pressed, and it is possible to perform high pressure even with a hard continuous cast material 1 such as high alloy steel. Furthermore, the angles of the taper parts 3 and 5 are almost the same. Since it is made less than 20 degrees, it is possible to prevent the pressed continuous cast material 1 from being restrained from being extended in the longitudinal direction by the tapered portions 3 and 5, and the press load required is reduced accordingly. Can be downsized and the equipment cost can be reduced.

[Brief description of drawings]

FIG. 1 is an explanatory view of an embodiment of the present invention, FIG. 2 is an explanatory view of a state in which the mold of FIG. 1 is arranged, FIG. 3 is an explanatory view of a heated slab for model experiment, and FIG. The figure shows how the drill holes are deformed non-uniformly in the longitudinal direction, Fig. 5 is a diagram showing the relationship between the longitudinal distance of hot steel and the hole height after deformation, and Fig. 6 is a slab. 6 (a) is a diagram showing the relationship between the distance from the width end of the hole and the amount of variation in the hole height in the longitudinal direction after deformation, FIG.
Shows the case where the die feed amount is 20 mm, FIG. 6 (b) shows the case where the die feed amount is 30 mm, and FIG. 6 (c) shows the case where the die feed amount is 40 mm. The diagram shown in FIG. 7, FIG. 7 is an explanatory diagram of a conventional example, FIG. 8 is an explanatory diagram of another conventional example, and FIG. 9 shows a state in which the reduction amount of the continuous cast material is periodically changed in the longitudinal direction. FIG. In the figure, 1 is a continuous cast material, 2 is the thickness center, 3 is a tapered portion, 4 is a horizontal portion, 5 is a tapered portion, 6 is a horizontal portion, and 7 is a two-stage mold.

Claims (1)

[Scope of utility model registration request] 1. A longitudinal direction (15) of the continuous cast material (1) on the pressure surface.
As it goes to the exit side, it approaches the thickness center (2) in the longitudinal direction (1
The taper part (3,5) whose angle to 5) is about 20 degrees or less,
A horizontal portion (4, 6) adjacent to the taper portion (3, 5) is formed in two steps by hanging from the inlet side to the outlet side of the continuous cast material (1), which is formed in two stages. Press mold.