JPH02169114A - Rough universal rolling mill for rolling h-shaped steel - Google Patents

Abstract

PURPOSE:To surely set rolls by forming the area in which vertical rolls correspond to flanges of a material to be rolled in a projecting arc shape of a radius having a starting point in the center of the roll and the side area in which horizontal rolls correspond to both end parts of a vertical roll in a recessed arc shape. CONSTITUTION:While each of a pair of vertical rolls 5, 5 and a pair of horizontal rolls 6, 6 are screwed down under a state free of material to be rolled, and zero point set of rolls is carried out easily without backlash. The vertical and the horizontal rolls are of circular arc contact, consequently, when the vertical rolls 5 incline, or, by whichever surface the material is rolled, the dimension of the flange not only can be kept at a fixed state but the difference between the flange thicknesses can be changed in steps. Further, since the contact part of each roll are by two point contact limited to both end parts, the gap between the rolls can set surely. Consequently, it is possible to manufacture a product excellent in dimension, shape and accuracy.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a universal rolling mill for rolling H-section steel, and is a rough universal rolling mill that can produce H-section steel with excellent dimensions and shape by improving the roll shape. The purpose is to provide the hole shape of the roll.

<Prior art> A typical universal rolling equipment train for H-beams consists of a breakdown rolling mill 1. 1st edger rolling mill2. First rough universal rolling mill 20, second rough universal rolling mill f121. Second edger rolling mill 2' and finishing universal rolling ill! Consisting of 4,
The first rough universal rolling mill 20 and the second universal rolling mill 21 each consist of a vertical roll 5.5' and a horizontal roll 6.6'.

The first edger rolling mill and the first rough universal rolling mill 20
The second edger rolling mill and the second t11 universal rolling mill 21 are each combined, but in addition to the case where the two sets are configured in this way, for example, there is a rolling equipment row in which one All or three or more sets are arranged. It is also well known that the relationship between the rough material and the finished dimensions of the product is not constant, depending on whether the entire equipment is tandem rolling or continuous rolling.

FIG. 4 shows the bus status of the rolled material 10 from the second roughing universal rolling mill 21 to the finishing universal rolling mill 4 in the above-mentioned rolling equipment row, and as shown in FIG. horizontal roll 6' of universal rolling mill 2I;
The web part of the material to be rolled 10 is rolled down at 6', and at the same time, the flange part is rolled down at vertical rolls 5', 5' and horizontal rolls 6', 6'. Edger roll 7 of Edger rolling mill 2'
．． At step 7, the flange end is rolled down. Subsequently, in finishing universal rolling W14, the web portion is lightly rolled down with the horizontal rolls 9, and at the same time, the flange portion is pressed with the vertical rolls 8, and the rolling is completed.

By the way, in the conventional rough universal rolling mill 21, there are a vertical roll 5' and a horizontal roll 6 for rolling down the flange part.
The gap t with ' is constant, and the wall thickness of the flange part is t. A rolled material 1 having a flange portion with such a wall thickness t
Figure 4 (b)
As shown in FIG. 2, the flange end of the rolled material 10 is deformed outward to form a bulging portion 10'.

In other words, since the inner side a of the flange end is in pressure contact with the edge roll 7, the machining action is formed into a nearly right-angled shape, whereas the outer side of the flange end is deformed. Since it is not restrained, it protrudes as a bulging part 10' by the amount corresponding to the reduction.

If this bulging part 10' remains and is rolled in the next finishing universal rolling a4, only one of the flange ends will be elongated by the elongation amount ΔF shown in FIG. As shown in C), the bulging part 10
An abnormally worn part C is formed on the horizontal roll 9 of the finishing universal rolling mill 4 corresponding to the back side of ', while the other parts C are averagely worn.

This elongation amount ΔF is determined by the final bath reduction amount in the edge rolling mill 2' and the cross-sectional area ratio between the web of the rolled material 10 and the flange, and is a heavy factor that determines the flange width dimension of the final product. , Bus schedule setting and dimension management have traditionally been performed with high precision. However, as mentioned above, there is a problem in that titration cannot be obtained with respect to the shape of the tip after finish rolling, especially the perpendicularity.

It is known that one way to make the bulging portion 10' as small as possible is to perform the final bath in the edger rolling mill 2' under light rolling, but it is well known that in actual rolling, variations occur in various rolling conditions. Although it was possible to reduce the size to a certain extent, it was not a complete countermeasure.

As a solution to the above problems, the Special Publication Publication No. 57-597
Publication No. 62 discloses an H-shaped steel rolling apparatus consisting of one or more sets of intermediate roughing universal rolling mills and finishing universal rolling mills, each of which is composed of a breakdown rolling mill, a Niziger rolling mill, and an Edger rolling mill.
Manufacture of IJ section steel with excellent flange perpendicularity, characterized by carrying out shaping rolling using an edger roll in which the inner corresponding part of the flange tip is formed in a granulated shape in the final stage edger rolling mill of the rolling mill. A method is proposed.

As proposed above, when rolling is carried out using an edger roll in which the inner corresponding part of the tip of the flange is formed in a granulated form, the bulging part that is generated at the flange end of the rolled material due to the engraving effect is made to correspond to the inner side of the flange end. Although it can be divided outwardly, the amount of bulging that occurs at the tip of the flange varies within the same cross section and in the rolling direction.

For this reason, in the flange-raised finish rolling by light web reduction in the next-stage finishing universal rolling mill, only the flange end is rolled, and if there is variation in the amount of bulging, it is likely that serrations will occur at the flange tip. This method not only causes twisting of the material to be rolled and deviation of the center, but also causes local wear of the rolls of the finishing universal rolling mill, particularly at the portion where the horizontal roll contacts the bulging portion at the tip of the flange.

<Problems to be Solved by the Invention> The present invention solves the problems of the prior art caused by bulging at the flange end by improving the roll shape of the rough universal rolling mill, while keeping the roll of the edger rolling mill in the conventional shape. It is an object of the present invention to provide a rough universal rolling mill for rolling H-section steel that can solve the problem.

Means for Solving the Problem> In order to achieve the above object, in a rough universal rolling mill for rolling H-section steel that combines a pair of upper and lower horizontal rolls and a pair of left and right vertical rolls, the pair of left and right vertical rolls is The area corresponding to the flanges of the rolled material is formed into a convex circular arc shape with a single radius starting from the center of the vertical roll over the entire width, while the pair of upper and lower horizontal rolls extends in the width direction of the vertical roll. Regions corresponding to both ends are each formed into a concave arc shape having the same radius as the convex arc shape of the vertical roll, and regions corresponding to the central portion in the radial direction are each formed into a straight line shape formed by a tangent to the concave arc shape. It is characterized by:

Further, in the present invention, preferably, the upper horizontal roll of the pair of upper and lower horizontal rolls has a region corresponding to the center part of the web of the material to be rolled in an arcuate shape having a depth equal to or less than the thickness tolerance of the web, and both ends of the web. The lower horizontal roll has a flat shape over the entire width of the region corresponding to the web of the material to be rolled.

<Example> Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows the horizontal roll 6.6 and the vertical rolls 5, 5 squeezed together without any material to be rolled. 1st
As shown in the figure, a pair of vertical rolls 5゜5 in the rough universal rolling mill of the present invention has a single radius RV starting from the center 0 of the vertical roll 5 over the entire width of the area corresponding to the flange of the material to be rolled. It has a convex arc shape.

On the other hand, a pair of upper and lower horizontal rolls 6.6 and a pair of vertical rolls 5, 5
The regions corresponding to both ends a in the width direction are each shaped like a concave arc having the same radius RV as the vertical roll 5, and the region 11 of eic corresponds to the central portion of the vertical roll 5 (this region is effective for rolling the flange). (used in the above) is a linear shape having an angle θ formed by a tangent to the concave arc shape of the horizontal roll 6.

Furthermore, the upper horizontal roll 6 of the pair of upper and lower horizontal rolls 6.6 forms an area corresponding to the center of the web of the material to be rolled into an arc shape with a depth ΔLtl - radius R11 within the web thickness tolerance, and both ends of the web. The region corresponding to the lower horizontal roll 6 has a flat shape, and the region where the lower horizontal roll 6 corresponds to the web of the material to be rolled has a flat shape over the entire width.

In the present invention, since the vertical rolls 5 and the horizontal rolls 6 have the above-described shape, when each roll is compressed by preloading without any material to be rolled, the upper and lower pairs of horizontal rolls 6.6
are in contact at both ends in the width direction, and are not in contact at the center with a maximum distance of △, forming a gap d. Conventionally, the horizontal rolls 6.6 had poor accuracy in setting the roll gap because their entire widths were in contact with each other, but in the present invention, a pair of left and right vertical rolls 5, 5 each having a convex arc shape at the end of the roll is used.
Both ends a in the width direction of the vertical rolls 5.
Since the range of the radius C of the horizontal roll 6.6 corresponding to the central part of , 5 is linear as described above, there is no contact and a gap e is formed. Conventionally, the rolls were in contact with each other over their entire widths, making it difficult to set the roll gap at 1n degrees, but in the present invention, the roll gap is in contact at both ends, which improves the setting accuracy.

The operation of the present invention will be explained below.

In the present invention, a pair of vertical rolls 5, 5 and a horizontal roll 6
．． As shown in FIG. 1, with no material to be rolled, the rolls can be easily zeroed by squeezing each roll and absorbing play.

In addition, since the vertical roll 5 and the horizontal roll 6 are in arcuate contact, the flange dimensions can not only be maintained constant no matter which surface the vertical roll 5 is rolled on, that is, the tilted state, but also the thickness difference of the flange can be changed in stages. Can be done. Furthermore, since the contact portions of each roll are limited to two points of contact at both ends, the roll gap can be set accurately.

In this way vertical rolls 5,5 and horizontal rolls 6.
6 is set, and then rough rolling is performed. As shown in FIG. 2, the material to be rolled 10 is formed with a thickness difference e' corresponding to the gap e shown in FIG. 1 at the center of the flange 10a. Even if a bulging portion 10' is formed at the tip of the flange 10a shown by the dotted line in FIG. 2 when the rolled material 10 having such a thickness difference e' is rolled with an edger roll, the bulging part 10' is formed at the tip of the flange 10a shown by the dotted line in FIG. A thickness difference part e' corresponding to the part 10' is rolled down at the same time.

This not only prevents meandering and waving of the flange end due to the bulging part 10', but also allows stable rolling to be performed without the extension ΔF of the flange end as shown in FIG. 4(d). can. As a result, not only a product with a good shape is obtained, but also local wear of the finishing mill is prevented.

In addition, during rough rolling, Δt
Since an arc-shaped bulge is formed, the cooling water flows into the web 10.
It flows to both sides of b, keeping the central part warm, and the flanged web tob, which has a relatively high temperature, cools the vicinity of the root well, reducing deformation and residual stress caused by temperature differences in each part. Improves accuracy.

<Effects of the Invention> As explained above, the present invention provides the following effects.

(1) The rolls of the universal rolling mill can be rolled accurately.

(2) It is possible to prevent meandering and waving of the rolled material due to the bulging portion that occurs at the tip of the flange.

(3) Residual stress and deformation due to temperature differences in various parts of the rolled material can be reduced.

(4) Local wear of the roll is prevented.

(5) Products with excellent dimensional and shape accuracy can be manufactured.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing an embodiment of the present invention, Fig. 2 is a schematic diagram showing the condition of a rolled material after rough universal mill rolling by the method of the present invention, and Fig. 3 is an example of a general H-beam rolling equipment. FIG. 4 is a schematic diagram showing a bus situation between a conventional roughing universal mill and a finishing universal mill. 9...Horizontal roll of finishing universal rolling mill, lO・
...Rolled material. 1... Breakdown rolling mill, 2... Edger rolling mill,

Claims (1)

[Scope of Claims] 1. In a rough universal rolling mill for rolling H-section steel that combines a pair of upper and lower horizontal rolls and a pair of left and right vertical rolls, an area where the pair of left and right vertical rolls correspond to the flanges of the material to be rolled. have a convex arc shape with a single radius starting at the center of the vertical roll over the entire width, while the pair of upper and lower horizontal rolls have side areas corresponding to both ends of the vertical roll in the width direction, respectively. It is characterized in that it has a concave arc shape having the same radius as the convex arc shape of the vertical roll, and the side area corresponding to the widthwise center portion of the vertical roll has a linear shape formed by a tangent to the concave arc shape. A rough universal rolling mill for rolling H-beam steel. 2. Among the pair of upper and lower horizontal rolls, the upper horizontal roll has a region corresponding to the center part of the web of the material to be rolled into an arcuate shape having a depth less than or equal to the thickness tolerance of the web, and also has regions corresponding to both ends of the web. 2. The rough universal rolling mill for rolling H-section steel according to claim 1, wherein the lower horizontal roll has a flat shape over its entire width in a region corresponding to the web of the material to be rolled.