JP2924687B2 - Roller straightening method and apparatus for H-section steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for straightening an H-section roller by lowering the bending of the H-section web by rolling down the web, and more particularly to a method for hot-rolling or welding. It relates to the straightening of H-section steel.

[0002]

2. Description of the Related Art H-shaped steels manufactured by hot rolling or welding are generally straightened in a cold state and then shipped because of bending or warping as a whole or locally. It is. In many cases, the cold straightening method is performed by press straightening or roller straightening. However, the former is not suitable for mass production because the former is appropriately deformed by a pressing tool while checking the shape before straightening. On the other hand, the latter (roller straightening method) is a method of straightening by repeatedly bending an H-section steel with a large number of rollers.
in use.

FIGS. 10 and 11 show a part of a contact state between a straightening roller and an H-shaped steel in a conventional roller straightening method, and show it. As can be seen in these figures, the load method of the conventional roller straightening machine has the configuration shown in FIG.
In FIG. 11, the web 3 of the H-shaped steel 1 is loaded by the outer peripheral surface of the roller 4 and the end face of the flange 3 of the H-shaped steel 1 is loaded by the outer peripheral surface of the roller 5 as shown in FIG. There are two types of monkey flange reduction system. However, whichever rolling down method is employed, the following problems cannot be avoided.

[0004] That is, the drawback of the web rolling method is that, in the case of an H-section steel whose flange width is wider than the web thickness, the load by the roller 4 is converted to the radius of the web 3 and the flange 2 is sufficiently bent. Roller 2 not only does not deform
In other words, only the local contact portion of the web 3 is plastically deformed, and in severe cases, a crack may even be generated at the root (hereinafter referred to as a fillet portion) between the flange 2 and the web 3. In Japanese Patent Publication No. 57-61488, in order to suppress such local deformation, the shape of a roll for holding the web 3 is devised. However, considering the situation where a product with a thinner web thickness is required, Such a method cannot solve the essential problem.

A disadvantage of the flange pressing down method is that when the flange width is large and a large bending load is required, the end face of the flange 2 in contact with the roller 5 is crushed, and the width of the flange 2 is greatly increased. Is to decrease. As described in Japanese Patent Publication No. Sho 56-40646 and Japanese Patent Laid-Open Publication No. Sho 53-141158, such problems are reduced by increasing the distance between the rollers, and by increasing the diameter of the roller 5 and the flange 5. Although this measure can be reduced to some extent by increasing the contact area with the roller 3, such a means not only inevitably leads to an increase in the size of the equipment and an increase in the construction cost, but also increases the interval between the rollers 5, thereby increasing the H-shape. Since the length of the uncorrectable portion at both ends of the steel also increases, these means naturally have limitations.

[0006]

As described above, it is obvious that the H-section steel having a large cross section cannot be effectively corrected by any of the web reduction method and the flange reduction method. The current state is to adopt a web rolling method. In order to solve the disadvantages of the above two methods, FIG.
(For example, Japanese Patent Publication No. Sho 57-11728), a method has been proposed in which the flange 2 and the web 3 are simultaneously lowered by the rollers 4 and 5, but this method is also distributed to the flange 2 and the web 3. It is difficult to set the load
If the height of the web 3 is also increased and the toes of the flange 2 may be crushed, the mechanism is complicated, and if the web thickness is further reduced, the above-mentioned problems are inevitably exposed.

Japanese Patent Publication No. Sho 56-45684 proposes a rather clever method for lowering the surface pressure applied to the flange when the flange is lowered. Because the speed is different, deformation is induced in the direction of the flange falling, the load on the part that starts to contact the flange and the part that comes off from the contact with the flange increases, and as a straightening machine, a special H-shaped steel machine And so on.

In Japanese Patent Application Laid-Open No. 4-59124,
We are trying to solve the local deformation of the web by increasing the bending rigidity of the web by restraining the flange by providing a vertical roll and restraining the flange in the web reduction straightening. When a large reduction force is applied to the web to correct it, the flange is actually constrained by the web reduction roll as shown in FIG. 5 (see the circles in the figure). The bending stiffness of the web is almost unchanged from the usual method. Therefore, simply restraining the movement of the flange by the vertical roll does not significantly change the deformation of the H-section steel compared to the conventional method, and cannot suppress the change in the height of the web. It is impossible to solve.

Another major problem with the conventional method is that it cannot effectively correct the collapse of the flange and the umbrella. JP-A-4-59124, JP-A-56-30027, JP-A-56-119624, and the like disclose that a vertical roll is provided, which is effective for the flange to fall and the umbrella to break. Is not an effective correction method because it is not based on the principle of correction.

The present invention has been made in order to solve the above-mentioned problems, and corrects the vertical bending of an H-section steel, suppresses a change in web height, reduces cracks in a fillet portion, and It is an object of the present invention to provide a method and an apparatus for straightening an H-section steel roller, which has a large effect of correcting a flange falling down and an umbrella bent, while reducing residual stress in a fillet portion.

[0011]

[Means for Solving the Problems]

(1) A method of straightening a roller of an H-section steel according to one embodiment of the present invention includes forming a web of an H-section steel by a plurality of horizontal rolls arranged alternately above and below the H-section steel along the traveling direction of the H-section steel. Pressing, and pinching the flange of the H-shaped steel by a horizontal roll and a vertical roll provided in a pair with the horizontal roll, giving a plastic deformation of the H-shaped steel to the flange of the H-shaped steel, thereby causing the flange in the height direction of the web to fall. The bending is applied repeatedly, and a compressive stress is applied to the fillet portion by the pressing force of the vertical roll. (2) In the roller straightening method for H-section steel according to another aspect of the present invention, the amount of plastic deformation of the flange applied to the flange is reduced and converged toward the downstream side. (3) A roller straightening device for an H-section steel according to another aspect of the present invention includes: a plurality of horizontal rollers for pressing a web of the H-section steel, alternately above and below the H-section steel along the traveling direction of the H-section steel. H
In the roller straightening device for section steel, a taper surface for giving a plastic deformation to the flange of the H-section steel is provided on an outer side surface, and a pair of taper presses respectively presses the web of the H-section steel and the inner side of the flange. With a pair of vertical rolls, each of which has a shape corresponding to the tapered surface thereof and presses the outer surface of the flange of the H-section steel. At least one set is provided, and the flange of the H-section steel is subjected to plastic deformation of falling to give a bending in the web height direction, and
A compressive stress is applied to the fillet portion of the H-section steel. (4) In the roller straightening device for an H-section steel according to another aspect of the present invention, in the device of the above (3), the angle of the tapered surface of the horizontal roll with a taper is set to be small toward the downstream side, and , The amount of plastic deformation caused by falling is reduced and converged toward the downstream side. (5) The roller straightening device for an H-section steel according to another aspect of the present invention is the device of the above (3) or (4), wherein the horizontal roll provided at the final stage has a gap with respect to the web surface of the H-section steel. Is arranged to have. That is, the present invention provides a horizontal roll having a tapered outer surface (or a similar shape), and a taper (or a similar shape) corresponding to the taper (or a similar shape) of the horizontal roll. ), A plastic deformation is repeatedly applied to the falling and umbrella of the flange from the outer surface of the flange of the H-steel, and the H-shaped steel is repeatedly bent and straightened. The above object is achieved by applying a compressive stress to the fillet portion.

[0012]

Next, the operation of the present invention will be described. FIG. 1 is a configuration diagram showing a basic configuration of the present invention. FIG. 3A is a side view, FIG. 3B is an operation explanatory view from the front, and FIG. 3C is a plan view. In this straightening device, horizontal rollers 10 for pressing the web along the traveling direction of the H-section steel are alternately arranged up and down, and a pair of vertical rolls 20 are provided corresponding to each horizontal roller 10. Have been. The outer side surface of the horizontal roller 10 is provided with a taper as shown, and the taper includes a taper inclined toward the center side and a taper inclined outward.
These are alternately arranged along the traveling direction of the H-section steel.
The side of the vertical roll 20 also has a shape corresponding to the side of the horizontal roller 10 corresponding thereto. The horizontal roller 10 disposed at the upper portion has a tapered surface extending outward as shown in FIG. 3B, but is inclined inward due to the negative taper angle of the horizontal roller 10 disposed at the lower portion. Is formed. The vertical roll 20 has a concave shape or a convex shape, the side of which corresponds to the shape of the outer side of the corresponding horizontal roll 10.

This straightening device applies a rolling force to the inner surface of the flange 2 of the H-shaped steel 1 by a tapered surface provided on the outer side surface of the horizontal roll 10 when correcting the bending of the H-shaped steel. From the outer surface of the flange 2, a horizontal roll 10
The H-shaped steel 1 is repeatedly bent by pinching the flange 2 with a vertical roll 20 having a tapered side portion having a shape corresponding to the tapered surface of the flange 2, and the fillet portion is formed by the vertical roll 20 from the outer surface of the flange 2. By applying a compressive stress to the web, there is no change in the height of the web, and correction is performed so as not to cause fillet cracks.

FIG. 1 shows an example in which a horizontal roller 10 having a taper and a vertical roll 20 are arranged on all the stands. At least one horizontal roller 10 having a taper and a taper corresponding thereto are provided. If the vertical roll 20 is provided, the effect can be exhibited.

FIG. 2 is an explanatory view showing the basic principle of correcting the shape by repeated bending. This repetitive bending can correct the shape of any initial shape. For example, the initial shape is κ01, κ02
(These shapes bend or fall in the opposite direction to each other) and κ03 (the same direction as κ01 but with a different degree of shape) can be repeatedly given κ1, κ2, κ3, and κ4. If the shape converges to zero point. Looking at the example of the initial shape κ01, it can be seen that the final shape converges to zero point, that is, a state without distortion, through the history as shown by the solid line in FIG. The same applies to the initial shapes κ02 and κ03.

In view of the above-described basic principle of correction, the following three points of awareness were obtained. In the initial stage of repeated bending for straightening up and down, a large bending moment must be given, and therefore, in the conventional web rolling method, the rolling force applied to the web increases and the web height changes. Or the fillet portion is cracked.
FIG. 9 is a view showing a stress state in a cross section of an H-shaped steel in a conventional web rolling method. The web is subjected to compressive and tensile stresses by bending by the roll, and the same stress is applied to the fillet portion. The flange portion is bent by pressing the web, and the toe has compressive and tensile stresses in the longitudinal direction, respectively. Changes in the height of the web and cracks in the fillet portion are mainly caused by the tensile stress, and it is necessary to reduce it in some way. There has not been proposed any method and apparatus for correcting various degrees of flange fall / umbrella break according to the above-described basic principle of correction. The fillet portion finishes the shape of the H-section steel by hot rolling, cools down last in the cooling process, and a large tensile residual stress remains.

The inventor of the present invention has found that the following method is effective for the above three points. In view of the above, since it is recognized that the change in the web height and the crack in the fillet portion are caused by tensile stress, it is necessary to positively apply a compressive stress to the fillet portion in order to reduce the change. It has been found that a compressive stress can be effectively applied to the fillet portion by combining a horizontal roll with a tapered outer side surface and a vertical roll having a corresponding taper angle.

FIG. 3 is a diagram showing the stress state at this time. It can be seen that the harmful tensile stress of the fillet portion is reduced to an elastic range by the compressive stress on the fillet portion. The taper angles θ1 and θ2 at this time are as shown in FIG. 4. However, from the above, in order to positively apply compressive stress to the fillet portion, the sum of these angles must be 90 degrees or less. Is desirable. At this time,
θ2> θ1.

In contrast, it is necessary to repeatedly bend the flange as shown in the arrangement of FIG. FIG. 3 is a view showing the stress state at this time. It can be seen that plastic deformation is applied to the flange 2 by repeatedly bending the flange 2. The combination of the vertical roll 20 and the horizontal roll 10 for repeatedly bending the flange 2 sequentially converges the taper angles to 90 degrees and 0 degrees, respectively. Further, when the web 2 is pushed into the horizontal roll at the final stage, the web 2 is bent and affects the perpendicularity to the flange 3. Therefore, it is desirable that the horizontal roll 10 and the vertical roll 20 be formed without lowering the web 2. The perpendicularity of the flange 3 is realized only by pinching. The convergence of this angle is adapted to the wind where the fillet portion is positively reduced at the place where the vertical bending is large, and the fillet portion is small at the place where the vertical bending is small in the subsequent stage. Things. In contrast, the above-described reduction of the fillet portion is effective for reducing the residual stress.

By the way, the installation intervals and the number of the vertical rolls 20 for applying the bending stress to the fillet portion while repeatedly bending the flange 2 in combination with the horizontal rolls 10 correspond to each stage of the conventional web pressing roller. It is desirable to install them individually, and the effect is exhibited in both driving and non-driving. Further, a combination of the horizontal roll 10 of the present invention and the vertical roll 20 combined with the horizontal roll 10 may be provided only in the front part where the load is large, and the rear part may adopt a configuration of normal roller correction of the flange 2 or the web 3. . Of course, the present invention can be applied to both cantilever type and doubly supported straightening machines. By properly laying a guide, a vertical roller set spacing adjusting device, a vertical position adjusting device, and a driving device for properly inserting the straightening device according to the present invention, the continuous section of H-section steel having various cross-sectional dimensions can be obtained. Effective correction is possible.

Here, the shape of the side surface of the horizontal roll and the shape of the vertical roll are tapered. However, any shape may be used as long as it can repeatedly bend the flange and apply compressive stress to the fillet portion. . For example,
The shape may be a parabola or a trigonometric function, and it is not always necessary to use a mathematically described function.

[0022]

【Example】

Embodiment 1 FIG. FIG. 6 is a view showing a configuration of an H-section steel roll straightening apparatus according to one embodiment of the present invention, in which the configurations shown in FIGS. 6A and 6B are alternately arranged. In this embodiment, a hydraulic cylinder 30 is provided as a mechanism for pressing the vertical roll 20 against the flange 2. Table 1 is a table showing the dimensions of the material to be corrected and the specifications of the straightening machine. Further, Table 2 is a table showing reduction settings for applying a compressive force to the fillet portion using an intermesh and a vertical roll as compared with the conventional web straightening method. Table 3 is a table showing combinations of the taper angles of the horizontal roll and the vertical roll. With this combination, it is possible to repeatedly bend the flange and to apply a compressive stress to the fillet portion efficiently. Table 4 compares the correction effect of the method of the present invention with the conventional method.

[0023]

[Table 1]

[0024]

[Table 2]

[0025]

[Table 3]

[0026]

[Table 4]

Therefore, according to the straightening according to the present embodiment, it can be seen that there is no change in the web height as compared with the conventional web reduction straightening.

FIG. 7 is a characteristic diagram showing a change in web height due to vertical roll reduction. From this characteristic, it is also understood that the web height itself can be controlled by the vertical roll rolling load. In FIG. 7, the data points for flange constraint are all vertical rolls and vertical rolls without taper. From this characteristic, simply constraining the flange by the vertical roll has no effect. I understand. In addition, all the data of FIG. 7 have shown the average value.

FIG. 8 is a characteristic diagram of the hardness distribution of the fillet portion. From this characteristic, it can be seen that the hardness of the fillet portion is increased by the reduction of the vertical roll, and the residual stress in this portion is reduced.

Embodiment 2 FIG. In this embodiment, a vertical roll is provided only on the upper roll. Table 5 shows the dimensions of the material to be straightened and the specifications of the straightening machine. Table 6 is a table showing an intermesh as compared with a conventional web straightening method. Table 7 is a table showing combinations of the taper angles of the horizontal roll and the vertical roll. Here, it was shown that the effect was exhibited even when the number of applied rolls was small, with repeated bending in the same direction. Table 8 shows the effect of the present invention as compared with the conventional method.

[0031]

[Table 5]

[0032]

[Table 6]

[0033]

[Table 7]

[0034]

[Table 8]

According to the correction according to the present embodiment, it can be seen that there is no change in the web height as compared with the conventional web reduction correction.

Embodiment 3 FIG. In the present embodiment, the vertical roll was installed only on the # 2 roll provided with the maximum straightening bend. Table 9 is a table showing the dimensions of the material to be corrected and the specifications of the straightening machine. Table 10 is a table showing an intermesh compared with a conventional web straightening method. Table 11 is a table showing combinations of horizontal rolls and vertical rolls. Here, the main purpose is to apply a compressive stress to the fillet portion. Table 12 is a table showing the effect of the method of the present invention as compared with the conventional method.

[0037]

[Table 9]

[0038]

[Table 10]

[0039]

[Table 11]

[0040]

[Table 12]

According to the straightening according to the present embodiment, it can be seen that there is no change in the web height as compared with the conventional web reduction straightening.

[0042]

As described above, according to the present invention, the web of the H-section steel is pressed by the horizontal roll, and the flange of the H-section steel is pinched by the horizontal roll and the vertical roll, so that the flange falls down. Since the H-shaped steel is straightened by applying plastic deformation to repeatedly bend in the web height direction and applying compressive stress to the fillet by the pressing force of the vertical roll, The bend is straightened,
Changes in web height are suppressed, cracks in the fillet portion are reduced, and residual stress in the fillet portion is reduced, so that a great correction effect can be obtained even for flange collapse and umbrella breakage.
Therefore, since there is no proper straightening method in the past, the H-shaped steel that has been straightened by pressing with a decrease in productivity can be efficiently shaped and an excellent effect of improving product quality can be exhibited.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a basic configuration of the present invention;
(A) is its side view, (b) is its front operation explanatory view,
(C) is a plan view.

FIG. 2 is an explanatory view showing the principle of shape correction by repeated bending in the present invention.

FIG. 3 is an explanatory view showing a stress state which changes according to a load of a compressive force by a vertical roll in the present invention.

FIG. 4 is an explanatory diagram showing definitions of a taper angle of a horizontal roll and a taper angle of a vertical roll in the method of the present invention.

FIG. 5 is an explanatory view showing a state of restraining a flange in a conventional method.

FIG. 6 is a view showing a configuration of an H-shaped steel straightening apparatus according to one embodiment of the present invention.

FIG. 7 is a characteristic diagram showing a change in web height due to vertical roll reduction according to the present invention.

FIG. 8 is a characteristic diagram showing a change in hardness distribution of a fillet portion under vertical roll pressure according to the present invention.

FIG. 9 is a diagram showing a stress state in a conventional correction method.

FIG. 10 is an explanatory view of a conventionally proposed H-section steel straightening method (1).

FIG. 11 is an explanatory view of a conventionally proposed H-shaped steel straightening method (2).

FIG. 12 is an explanatory view of a conventionally proposed H-shaped steel straightening method (3).

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Makoto Watanabe 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (72) Inventor Toru Morimi 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Inside (72) Inventor Atsushi Watanabe 1-2-1, Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (56) References JP-A-3-285721 (JP, A) JP-A-62-268624 (JP) , A) JP-A-57-137028 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B21D 3/05

Claims (5)

(57) [Claims] 1. Up-and-down movement of an H-beam along the traveling direction of the H-beam.
The horizontal rolls are arranged alternately in the
The horizontal roll and the horizontal roll.
The flanges of the H-section steel are pinched by the vertical rolls provided in the pair, and the flanges of the H-section steel are subjected to plastic deformation of falling to repeatedly bend in the web height direction, and the pressing of the vertical rolls is performed. A method for correcting an H-section steel roller, wherein a compressive stress is applied to a fillet portion by pressure. 2. The amount of plastic deformation of the flange falling down.
And converge by decreasing the size as it goes downstream.
The method for straightening a roller of an H-section steel according to claim 1, wherein: 3. A horizontal roller for pressing a web of H- section steel.
Plural alternately arranged above and below the H-section along the direction of travel of the H-section
In the placed H-beam roller straightening device, the outer side surface portion has a tapered surface for giving plastic deformation to the H-beam flange, and presses the H-shaped steel web and the inner surface of the flange, respectively. A pair of tapered horizontal rolls, provided respectively corresponding to the tapered horizontal roll,
The side part has a shape corresponding to the tapered surface, has at least one set of a pair of vertical rolls for pressing the outer surface of the flange of the H-section steel, and the flange of the H-section steel. A roller straightening apparatus for an H-section steel, wherein the apparatus is subjected to plastic deformation such that it is bent in the height direction of the web and compressive stress is applied to a fillet portion of the H-section steel. 4. The tapered horizontal roll has a taper.
The angle of the par surface is set smaller toward the downstream side,
The amount of plastic deformation caused by the fall of the flange
4. The method according to claim 3, wherein the convergence is made smaller.
H-section roller straightening device. 5. A roller straightening device for an H-section steel according to claim 3, wherein the horizontal roll provided at the last stage is disposed so as to have a gap with respect to the web surface of the H-section steel. .