JP2516892B2 - Rolling method 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 rolling method for freely adjusting the height of a H-section steel web during rolling.

[0002]

2. Description of the Related Art At present, H-section steel manufactured by hot rolling has a very large size and size depending on the application, but in recent years, there has been a reduction in the weight of structures using these and economical design. From the point of view, their size size types tend to increase further. If the known conventional technology can cope with such a tendency, there are the following problems.

Generally, the rolling mill arrangement for producing H-section steel
The columns are as shown in Figure 5 of the accompanying drawings and break
Down rolling mill BD, first edging rolling mill RE 1, first
Coarse universal rolling mill RU 1, second rough universal rolling
Machine RU 2, second edging rolling mill RE 2, finish uni
Rolled by monkey rolling mill FU. This traditional universal
The dimensions of H-section steel obtained by the rolling method are shown in Fig. 6.
Web height H, web inner width LH, flange thickness
t If 2, then H = LH + 2t2, and
The width LH is a finish universal if the amount of heat shrinkage during cooling is ignored.
Same as the horizontal roll width of the rolling mill (LHF in Fig. 5)
Therefore, the web height H is the water of the finishing universal rolling mill.
Determined by flat roll width and flange thickness.

Therefore, for example, an H-section steel having a constant web height regardless of the amount of change in the flange thickness, or conversely, an H-section steel having a constant flange thickness and capable of making the web height an arbitrary dimension is manufactured. In such a case, it is necessary to prepare the horizontal roll width of the universal rolling mill according to the size of the H-section steel to be rolled. Therefore, the number of dimensions to be rolled increases regardless of the flange thickness t2 and the web inner width LH.
Each time the number of rolls held increases, and each time the dimensional size to be rolled changes, it is necessary to replace the rolls with a roll that matches the size, which results in a significant decrease in operating rate. Further, during the rolling, the rolling roll is worn due to contact with the material to be rolled, and the horizontal roll width such as LHF in FIG. 5 is reduced, so that the web height H or the flange thickness t2 of the rolled product varies. Therefore, the horizontal roll cannot be repeatedly used for a certain rolling size and used for a long period of time. Due to these factors, it has been almost impossible to economically manufacture to satisfy the demands of customers for various kinds and sizes of products.

[0005]

In the conventional method, since the roll cylinder length is fixed or constant for each roll as described above, it is necessary to prepare the rolling rolls according to the rolling size. Immense,
There is a problem that the operation rate is significantly reduced because the rolls are rearranged, the product dimensions vary due to roll wear during rolling, and the same rolling roll of the same size cannot be used repeatedly for a long time. .

The present invention has been made in order to solve the above-mentioned problems, without increasing the number of rolls held,
An object of the present invention is to provide a rolling method of H-section steel which can freely adjust the web height with good workability without lowering the operation rate and rolling efficiency, while ensuring high quality and high yield. .

[0007]

According to the present invention, the above objects are achieved by a breakdown rolling mill, a rough universal rolling mill,
On the rear surface of the edging rolling machine of the normal H-shaped steel hot rolling equipment consisting of the edging rolling machine and the finishing universal rolling machine, two rolling annular sleeves are coaxially fitted on the roll shaft so as to be rotatable integrally with the roll shaft. At the same time, a rolling mill having a pair of upper and lower rolling rolls formed by movably forming at least one of the annular sleeves in the axial direction of the roll is installed in close proximity, and further, on the rear surface of the rolling mill, a rough universal rolling mill is installed. In the rolling method of H-section steel with a rolling facility equipped with a rolling mill equipped with a pair of upper and lower rolling rolls having a roll width less than the horizontal roll width, the shape of which is roughly barrel-shaped, and the roll width of which is fixed, a break occurs. Coarse universal rolling of a material to be rolled that has been rolled into a substantially H shape by a down rolling mill into a shape capable of forming excess thickness at the root of the flange and web and both ends of the web And repeating the universal thickness reduction of the flange and the web and controlling the flange width using the rolls of the edging mill and forming a surplus near the root of the flange and the web and both end portions of the web. The material to be universally rolled is set on the rear surface of the edging rolling mill, and the rolling width is set to be larger than the width of the horizontal roll of the rough universal rolling mill by a rolling mill incorporating a roll with variable roll width. By rolling, the inner width of the mechanical web is expanded due to the difference in roll width, and at the same time, the excess thickness is rolled to the same thickness as the central part of the web in the final pass of the rough universal rolling to reduce most of the area reduction. One stage of rolling for converting into an increase in the inner width of the web, and then a rolling machine equipped with rolls whose width is variable. With a rolling machine equipped with a pair of upper and lower rolling rolls that are roughly barrel-shaped installed on the surface and whose roll width is fixed, the web of the material to be rolled is rolled, and the same surplus as at the completion of the rough universal rolling is obtained. Rolling is further performed by forming a roll on both ends of the web and rolling the material to be rolled by setting a roll width larger than the inner width of the web in the previous stage by a rolling mill incorporating a roll whose roll width is variable again. At the stage of increasing the inner width of the web by rolling the width difference and excess thickness part, and further, in the coarse universal rolling machine, open the roll gap between the vertical roll and the horizontal roll side wall so as not to roll down the flange part, and only the upper and lower horizontal rolls. In the step of forming the excess thickness of the web of the material to be rolled in the same manner as the rolling with the fixed-width roll of the above-mentioned barrel type, further rolling using the roll whose roll width is variable, and the web inner width is Similarly expanding stage It is achieved by repeating and.

[0008]

As described above, according to the present invention, first, the step of forming excess thickness at the root portion of the flange and the web and both end portions of the web is performed by the rough universal rolling mill and the rolling mill equipped with a pair of upper and lower rolling rolls of a roughly barrel type. To do. Subsequent to this step, with a rolling mill equipped with a pair of upper and lower rolling rolls with adjustable roll width, the rolling roll width is set to be larger than the web inner width in the above step, and mechanical rolling Along with the increase of the inner width of the web, a step of converting most of the surface reduction amount into the increase of the inner width of the web is performed by pressing down the surplus thickness formed in the above step to the same thickness as the central portion of the web in the above step.

A predetermined web height can be obtained by appropriately repeating these two steps.

[0010]

Embodiments of the present invention will be described below with reference to FIGS. 1 to 4 of the accompanying drawings.

FIG. 1 is a diagram showing an outline process of the present invention.
For ease of understanding, edging rolling is omitted. FIG. 2 shows an arrangement of rolling mills for carrying out the present invention. In the drawing, the second rough rolling mill group R2 includes a second rough universal rolling mill RU2, a second edging rolling mill RE2, and a rear surface of the second edging rolling mill. Two rolling annular sleeves are coaxially and rotatably fitted on the roll shaft, and at least one of the annular sleeves is formed so as to be movable in the roll axial direction. The rolling mill RY1 is further equipped with a pair of upper and lower rolling rolls having a roll width equal to or less than the horizontal roll width of the rough universal rolling mill, its shape is roughly barrel-shaped, and its roll width is fixed on the rear surface thereof. There are a total of four rolling mills, namely, the rolling mill RY2.

In FIG. 1, the state (a) is a second roughening of the material to be rolled which is rolled into a substantially H shape by the breakdown rolling mill BD or the first rough universal rolling mill RU1 and the first edging rolling mill RE1 shown in FIG. Universal rolling mill RU
2 and the second edging rolling mill RE2 are shown in a state where they are rolled for several passes. This rolled material 1a has a roll width LH
Since a horizontal roll 11h having a fixed width of 11 and a vertical roll 11v are used for rolling, the web inner width LH12 is substantially equal to the roll width LH11. The roll end of the horizontal roll 11h has a shape that forms a flange on the material to be rolled 1a, a root of the web, and a surplus at both ends of the web.
Therefore, it is rolled into the shape of the rolled material 1a shown in the state (a) in FIG. The surplus amounts a and b shown in FIG. 3 are determined in consideration of the amount of expansion of the inner width of the web and the stability of rolling in the subsequent step (for example, the state (b) in FIG. 1). At this stage of the main rolling, the second rough universal rolling mill RU2 and the second edging rolling mill RE2 (not shown in FIG. 1) are used to perform normal universal rolling. Two installed rolling mills RY1 and R
Y2 is unnecessary. In this case, RY1 sets the roll width (for example, LH21 in the state (b) in FIG. 1) to be narrower than LH11, and sets the roll gap formed by the upper and lower rolls to a wide so-called empty path (rolling without rolling). Only pass the material). Since RY2 is a fixed width roll, its roll width is the second rough universal rolling machine RU.
The width LH11 of the second horizontal roll is set to LH11 or less, and the roll gap is set wide to perform an empty pass.

Rolled material 1a in the state (a) shown in FIG.
The state in which the inner width of the web is rolled by the rolling mill RY1 installed near the rear surface of the second edging rolling mill is shown in the state (b) in FIG. First, the width (roll width) of the rolling annular sleeve 12 of the RY1 rolling mill is changed from LH21 to LH21> LH.
The rolling material 1a is set so that the rough universal rolling is completed, and the material to be rolled 1a is rolled. Rolled material 1a on RY1 rolling mill
The web is mechanically stretched by the roll width difference (LH21-LH11) in the process of biting. By rolling the excess web portion with the rolling annular sleeve 12 (rolling roll), most of the amount of surface reduction of the excess thickness is converted to increase the inner width of the web. In this case, the vertical roll is used like universal rolling, and the flange is not rolled.
This is because the elongation in the lengthwise direction (rolling direction) of the web surplus portion due to rolling is regulated by the flange, and most of the surface reduction amount is converted to increase the web inner width. Further, as shown in the state (a) in FIG. 1, the excess thickness is formed at both ends of the web by rolling the excess thickness at both ends of the web rather than rolling the excess thickness at the center of the web. This is because it is easy to prevent the buckling of the web due to the difference in elongation in the lengthwise direction caused by the difference in the rolling reduction of each section. Further, stretching of the web in the width direction due to the difference in roll width is also very effective in preventing web buckling because the force acts in the web width direction. Therefore, the inner web width of the material to be rolled 1b causes the web to buckle to LH22. Be expanded without. Further, in the rolling of the extra thickness portion, the roll gap is set so as to be equal to the thickness t11 of the central portion of the web at the completion of the rough universal rolling in the state (a) in FIG. Needless to say, after the above steps, if the inner width of the web is sufficiently expanded, the material 1b to be rolled may be subjected to finish rolling shown in the state (g) in FIG. This finish rolling mill FU is a universal rolling mill having horizontal rolls 14h and vertical rolls 14v having the same structure as the rolling rolls 12 of the RY1 rolling mill and having a variable roll width. The roll width LHF of the horizontal rolls 14h is the product web. It is determined in consideration of the amount of heat shrinkage with respect to the inner width LH. The finish rolling in this case is mainly to raise the angle of the flange, and there is almost no reduction of the web. Therefore, the web thickness t1 of the rolled material 1g is substantially equal to t11.
When it is necessary to further increase the inner width of the web, the rolled material 1b in the state (b) shown in FIG. 1 is rolled by the rolling machine RY2 having a pair of horizontal barrels arranged roughly on the rear surface of the RY1 rolling. Rolling is performed as in the state (c) in Fig. 1 and then rolling in the order of states (d), (e) and (f) in Fig. 1. In this case, it goes without saying that the thickness of the web is t11>t12> t13.

First, the rolled material 1b in the state (b) in FIG. 1 is rolled so that the thickness of the central portion of the web is t12 as in the state (c) in FIG. By the main rolling, a margin similar to the state (a) in FIG. 1 is formed at both ends of the web.
The material 1c to be rolled after the main rolling is rolled again by the RY1 rolling mill (state (d) in FIG. 1). In this case, the roll width LH41 of the RY1 rolling mill is set under the condition of LH41> LH32, and the thickness of the excess thickness portion is rolled to t12. The material 1d to be rolled, which has been rolled, is rolled using the rough universal rolling machine RU2 so that the thickness of the central portion of the web becomes t13. In this case, the web thickness t13 in this case is made substantially equal to the web thickness t1 of the finish-rolled material 1g. Further, in the rolling in the state (e) in FIG. 1, since the inner width of the web is expanded up to the state (d) in the previous step, the rough universal rolling machine RU2
It is larger than the width LH11 of the horizontal roll 11h. Therefore, as shown in the state (e) in FIG. 1, the vertical roll 11v needs to have a gap so that the flange cannot be pressed between the vertical roll 11v and the side wall of the horizontal roll 11h. By this rolling, as shown in the state (e) in FIG. 1, extra thickness is formed again at both ends of the web. The material to be rolled 1e is rolled by the RY1 rolling machine in the same manner as described above so that the roll width LH61 is set to LH61> LH52 and the excess thickness portion is rolled to t13 (state (f) in FIG. 1).

Needless to say, the above steps are repeated when it is necessary to further increase the inner width of the web. The material 1f to be rolled after the process (rolling) up to the state (f) in FIG. 1 above is subjected to finish rolling shown in the state (g) in FIG. 1 to complete the hot rolling of the H-section steel.

Incidentally, FIG. 4 shows an example of a method of operating the rolling mill in each of the above steps. In the figure, a circle indicates that the rolling is performed.

[0017]

As described above, according to the present invention, the excess thickness is formed near the flange of the H-section steel and the root of the web and at both ends of the web, and when the excess thickness is rolled, the inner width of the front web is increased. By setting a larger roll width, mechanical stretching due to roll width difference and surface reduction due to excess thickness reduction can be combined with the roll width to convert most of it to increase the web height. (Web height) The expansion effect is great, there is almost no risk of web buckling due to the difference in the rolling reduction, and excess thickness is formed at both ends of the web on both front and rear surfaces of the rolling mill in the process of expanding the inner width of the web. By setting up a rolling mill that can reciprocate, the inner width of the web can be expanded, so the web height can be adjusted freely with a small number of passes, and thus the rolling efficiency is high.
Since the effect of expanding the inner width of the web is large, it is possible to share the rolling rolls for various sizes with different web heights, and therefore it is not necessary to increase the number of rolls held for increasing the size. There is no fear of product defects and the dimensional control accuracy is high over the entire length of the material to be rolled. As a result, high quality and high yield can be produced.

[Brief description of drawings]

FIG. 1 is a diagram showing steps of a rolling method of the present invention.

FIG. 2 is a cross-sectional view of a rolling mill arrangement and rolls and H-section steel for carrying out the present invention.

FIG. 3 is a diagram showing a flange formed at the time of completion of rough universal rolling, a root vicinity of the web, and a surplus shape of both ends of the web.

FIG. 4 is a diagram showing an example of a method of operating a rolling mill in each step of the present invention.

FIG. 5 is a cross-sectional view showing a conventional H-section steel rolling process, a rolling roll configuration of each rolling mill, and a shape of a material to be rolled.

FIG. 6 is a sectional view showing a dimensional relationship of the H-section steel.

[Explanation of symbols]

1, 1a, 1b, 1c, 1d, 1e, 1f, 1g Rolled material 11h Horizontal roll of rough universal rolling mill 11v Vertical roll of rough universal rolling mill 12 RY1 Annular sleeve for rolling of rolling mill 13 RY2 Outline barrel of rolling mill Type horizontal roll 14h Rolling annular sleeve for horizontal roll of finish universal rolling mill 14v Vertical roll of finish universal rolling mill BD Breakdown rolling mill R1 First rough rolling mill group R2 Second rough rolling mill group F Finish rolling mill RE1 No. One edging rolling mill RU1 First rough universal rolling mill RU2 Second rough universal rolling mill RE2 Second edging rolling mill RY1 Two rolling annular sleeves are coaxially and rotatably fitted on a roll shaft and at least One of the rolling sleeves is formed by movably forming one of the annular sleeves in the roll axial direction. Installed rolling mill RY2 Rolling mill FU Finishing universal equipped with a pair of upper and lower rolling rolls whose roll width is less than horizontal roll width of coarse universal rolling mill and whose shape is roughly barrel-shaped and whose roll width is fixed Rolling machine LH11, LH21, LH31, LH41, LH61, LHF Roll width LH12, LH22, LH32, LH42, LH52, LH62,
Web width of H-section steel

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyotaka Maruuchi 1-2-2 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (72) Takashi Arizumi 1-2-1 Marunouchi, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (72) Inventor Furukawa Zun Marunouchi 1-2-2, Chiyoda-ku, Tokyo Japan Steel Pipe Co., Ltd. (56) Reference JP-A-2-89502 (JP, A) JP-A-63-72402 ( JP, A)

Claims (2)

(57) [Claims] 1. Rolling two roll shafts on the rear surface of an edging rolling machine of a normal H-section steel hot rolling equipment comprising a breakdown rolling machine, a rough universal rolling machine, an edging rolling machine and a finishing universal rolling machine. A rolling mill having a pair of upper and lower rolling rolls formed by fitting at least one annular sleeve coaxially with the roll shaft so as to be rotatable integrally with the roll shaft, and at least one of the annular sleeves being formed so as to be movable in the axial direction of the roll. Installed on the rear surface of the rolling mill with a pair of upper and lower rolling rolls whose roll width is equal to or less than the horizontal roll width of the rough universal rolling mill and whose shape is roughly barrel-shaped and whose roll width is fixed. In a method for rolling H-shaped steel by a rolling facility equipped with a rolling mill, a material to be rolled rolled into a substantially H shape by a breakdown rolling mill is used to form a flange and a root portion of a web and a wedge. Web is used to perform normal universal rolling using rolls of a rough universal mill and an edging mill that have a shape capable of forming excess thickness, and repeatedly reduce the thickness of flange and web and control the flange width, and And a step of forming a surplus near the root of the web and both end portions of the web, and using a rolling mill incorporating a roll with a variable roll width, which is installed on the rear surface of the edging rolling mill, the material to be rolled having undergone rough universal rolling. By setting the roll width to be larger than the width of the horizontal roll of the rough universal rolling mill and expanding the inner width of the mechanical web due to the difference in roll width, the above-mentioned surplus portion is used as the central portion of the web in the final pass of the rough universal rolling. One pass of rolling that converts most of the surface reduction amount to increase the inner width of the web by rolling to the same thickness And subsequently, in a rolling machine equipped with a pair of upper and lower rolling rolls, each of which is a roughly barrel type installed on the rear surface of a rolling machine equipped with a roll having a variable roll width, and has a fixed roll width. Rolling the web, and forming a surplus at the both ends of the web similar to the completion of the rough universal rolling, and the pre-stage of the material to be rolled again in a rolling mill incorporating a roll with a variable roll width. Roll width is set to be larger than the web inner width at the stage of rolling to further increase the web inner width by rolling the roll width difference and excess thickness part, and further, in the rough universal rolling machine, do not reduce the flange part. To open the roll gap between the vertical roll and the horizontal roll side wall, the step of performing the excess thickness formation similar to the rolling of the web of the material to be rolled with only the upper and lower horizontal rolls with the fixed width roll of the above-mentioned barrel type, and further subsequently. The roll width is Rolled by using a modification roll, rolling method of H-beams, characterized by repeating the steps of expanding the web in width as well. 2. A horizontal roll in which two rolling annular sleeves are coaxially and rotatably fitted together with the roll shaft so that at least one of the annular sleeves is movable in the roll axial direction. The rolling of H-section steel according to claim 1, wherein the finishing universal rolling mill adjusts and sets the outer width between both annular sleeves of the horizontal roll so as to match the inner width of the web of the material to be rolled. Method.